Shortcut for for statement

Don't attempt to install stackprof gem on JRuby

.github/probots.yml

@@ -0,0 +1,2 @@
+enabled:
+  - cla

.gitignore

@@ -1,3 +1,9 @@
+*~
 *.gem
 *.swp
 pkg
+*.rbc
+.rvmrc
+.ruby-version
+Gemfile.lock
+.bundle

.rubocop.yml

@@ -0,0 +1,132 @@
+inherit_from:
+  - .rubocop_todo.yml
+  - ./.rubocop_todo.yml
+
+AllCops:
+  Exclude:
+    - 'performance/shopify/*'
+    - 'pkg/**'
+
+Metrics/BlockNesting:
+  Max: 3
+
+Metrics/ModuleLength:
+  Enabled: false
+
+Metrics/ClassLength:
+  Enabled: false
+
+Lint/AssignmentInCondition:
+  Enabled: false
+
+Lint/AmbiguousOperator:
+  Enabled: false
+
+Lint/AmbiguousRegexpLiteral:
+  Enabled: false
+
+Lint/ParenthesesAsGroupedExpression:
+  Enabled: false
+
+Lint/UnusedBlockArgument:
+  Enabled: false
+
+Layout/EndAlignment:
+  EnforcedStyleAlignWith: variable
+
+Lint/UnusedMethodArgument:
+  Enabled: false
+
+Style/SingleLineBlockParams:
+  Enabled: false
+
+Style/DoubleNegation:
+  Enabled: false
+
+Style/StringLiteralsInInterpolation:
+  Enabled: false
+
+Style/AndOr:
+  Enabled: false
+
+Style/SignalException:
+  Enabled: false
+
+Style/StringLiterals:
+  Enabled: false
+
+Style/BracesAroundHashParameters:
+  Enabled: false
+
+Style/NumericLiterals:
+  Enabled: false
+
+Layout/SpaceInsideArrayLiteralBrackets:
+  Enabled: false
+
+Layout/SpaceBeforeBlockBraces:
+  Enabled: false
+
+Style/Documentation:
+  Enabled: false
+
+Style/ClassAndModuleChildren:
+  Enabled: false
+
+Style/TrailingCommaInArrayLiteral:
+  Enabled: false
+
+Style/TrailingCommaInHashLiteral:
+  Enabled: false
+
+Layout/IndentHash:
+  EnforcedStyle: consistent
+
+Style/FormatString:
+  Enabled: false
+
+Layout/AlignParameters:
+  EnforcedStyle: with_fixed_indentation
+
+Layout/MultilineOperationIndentation:
+  EnforcedStyle: indented
+
+Style/IfUnlessModifier:
+  Enabled: false
+
+Style/RaiseArgs:
+  Enabled: false
+
+Style/PreferredHashMethods:
+  Enabled: false
+
+Style/RegexpLiteral:
+  Enabled: false
+
+Style/SymbolLiteral:
+  Enabled: false
+
+Performance/Count:
+  Enabled: false
+
+Naming/ConstantName:
+  Enabled: false
+
+Layout/CaseIndentation:
+  Enabled: false
+
+Style/ClassVars:
+  Enabled: false
+
+Style/PerlBackrefs:
+  Enabled: false
+
+Style/TrivialAccessors:
+  AllowPredicates: true
+
+Style/WordArray:
+  Enabled: false
+
+Naming/MethodName:
+  Exclude:
+    - 'example/server/liquid_servlet.rb'

.rubocop_todo.yml

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+# This configuration was generated by
+# `rubocop --auto-gen-config`
+# on 2019-03-19 11:04:37 -0400 using RuboCop version 0.53.0.
+# The point is for the user to remove these configuration records
+# one by one as the offenses are removed from the code base.
+# Note that changes in the inspected code, or installation of new
+# versions of RuboCop, may require this file to be generated again.
+
+# Offense count: 1
+# Cop supports --auto-correct.
+# Configuration parameters: Include, TreatCommentsAsGroupSeparators.
+# Include: **/*.gemspec
+Gemspec/OrderedDependencies:
+  Exclude:
+    - 'liquid.gemspec'
+
+# Offense count: 5
+# Cop supports --auto-correct.
+# Configuration parameters: EnforcedStyle.
+# SupportedStyles: auto_detection, squiggly, active_support, powerpack, unindent
+Layout/IndentHeredoc:
+  Exclude:
+    - 'test/integration/tags/for_tag_test.rb'
+    - 'test/integration/trim_mode_test.rb'
+
+# Offense count: 6
+# Cop supports --auto-correct.
+# Configuration parameters: EnforcedStyle.
+# SupportedStyles: symmetrical, new_line, same_line
+Layout/MultilineMethodCallBraceLayout:
+  Exclude:
+    - 'test/integration/error_handling_test.rb'
+    - 'test/unit/strainer_unit_test.rb'
+
+# Offense count: 2
+# Cop supports --auto-correct.
+# Configuration parameters: EnforcedStyle.
+# SupportedStyles: runtime_error, standard_error
+Lint/InheritException:
+  Exclude:
+    - 'lib/liquid/interrupts.rb'
+
+# Offense count: 1
+# Configuration parameters: CheckForMethodsWithNoSideEffects.
+Lint/Void:
+  Exclude:
+    - 'lib/liquid/parse_context.rb'
+
+# Offense count: 54
+Metrics/AbcSize:
+  Max: 56
+
+# Offense count: 12
+Metrics/CyclomaticComplexity:
+  Max: 12
+
+# Offense count: 112
+# Configuration parameters: CountComments.
+Metrics/MethodLength:
+  Max: 37
+
+# Offense count: 8
+Metrics/PerceivedComplexity:
+  Max: 11
+
+# Offense count: 52
+# Configuration parameters: Blacklist.
+# Blacklist: END, (?-mix:EO[A-Z]{1})
+Naming/HeredocDelimiterNaming:
+  Exclude:
+    - 'test/integration/assign_test.rb'
+    - 'test/integration/capture_test.rb'
+    - 'test/integration/trim_mode_test.rb'
+
+# Offense count: 23
+# Configuration parameters: MinNameLength, AllowNamesEndingInNumbers, AllowedNames, ForbiddenNames.
+# AllowedNames: io, id
+Naming/UncommunicativeMethodParamName:
+  Exclude:
+    - 'example/server/example_servlet.rb'
+    - 'lib/liquid/condition.rb'
+    - 'lib/liquid/context.rb'
+    - 'lib/liquid/standardfilters.rb'
+    - 'lib/liquid/tags/if.rb'
+    - 'lib/liquid/utils.rb'
+    - 'lib/liquid/variable.rb'
+    - 'test/integration/filter_test.rb'
+    - 'test/integration/standard_filter_test.rb'
+    - 'test/integration/tags/for_tag_test.rb'
+    - 'test/integration/template_test.rb'
+    - 'test/unit/condition_unit_test.rb'
+
+# Offense count: 10
+# Cop supports --auto-correct.
+# Configuration parameters: EnforcedStyle.
+# SupportedStyles: prefer_alias, prefer_alias_method
+Style/Alias:
+  Exclude:
+    - 'lib/liquid/drop.rb'
+    - 'lib/liquid/i18n.rb'
+    - 'lib/liquid/profiler/hooks.rb'
+    - 'lib/liquid/standardfilters.rb'
+    - 'lib/liquid/tag.rb'
+    - 'lib/liquid/tags/include.rb'
+    - 'lib/liquid/variable.rb'
+
+# Offense count: 22
+Style/CommentedKeyword:
+  Enabled: false
+
+# Offense count: 1
+# Cop supports --auto-correct.
+# Configuration parameters: EnforcedStyle, SingleLineConditionsOnly, IncludeTernaryExpressions.
+# SupportedStyles: assign_to_condition, assign_inside_condition
+Style/ConditionalAssignment:
+  Exclude:
+    - 'lib/liquid/errors.rb'
+
+# Offense count: 1
+Style/DateTime:
+  Exclude:
+    - 'test/unit/context_unit_test.rb'
+
+# Offense count: 2
+# Cop supports --auto-correct.
+Style/EmptyCaseCondition:
+  Exclude:
+    - 'lib/liquid/block_body.rb'
+    - 'lib/liquid/lexer.rb'
+
+# Offense count: 5
+# Cop supports --auto-correct.
+# Configuration parameters: EnforcedStyle.
+# SupportedStyles: compact, expanded
+Style/EmptyMethod:
+  Exclude:
+    - 'lib/liquid/tag.rb'
+    - 'lib/liquid/tags/comment.rb'
+    - 'lib/liquid/tags/include.rb'
+    - 'test/integration/tags/include_tag_test.rb'
+    - 'test/unit/context_unit_test.rb'
+
+# Offense count: 3
+# Cop supports --auto-correct.
+Style/Encoding:
+  Exclude:
+    - 'lib/liquid/version.rb'
+    - 'liquid.gemspec'
+    - 'test/integration/standard_filter_test.rb'
+
+# Offense count: 2
+# Cop supports --auto-correct.
+Style/ExpandPathArguments:
+  Exclude:
+    - 'Rakefile'
+    - 'liquid.gemspec'
+
+# Offense count: 7
+# Configuration parameters: EnforcedStyle.
+# SupportedStyles: annotated, template, unannotated
+Style/FormatStringToken:
+  Exclude:
+    - 'test/integration/filter_test.rb'
+    - 'test/integration/hash_ordering_test.rb'
+
+# Offense count: 14
+# Configuration parameters: MinBodyLength.
+Style/GuardClause:
+  Exclude:
+    - 'lib/liquid/condition.rb'
+    - 'lib/liquid/lexer.rb'
+    - 'lib/liquid/strainer.rb'
+    - 'lib/liquid/tags/assign.rb'
+    - 'lib/liquid/tags/capture.rb'
+    - 'lib/liquid/tags/case.rb'
+    - 'lib/liquid/tags/for.rb'
+    - 'lib/liquid/tags/include.rb'
+    - 'lib/liquid/tags/raw.rb'
+    - 'lib/liquid/tags/table_row.rb'
+    - 'lib/liquid/variable.rb'
+    - 'test/unit/tokenizer_unit_test.rb'
+
+# Offense count: 1
+# Cop supports --auto-correct.
+# Configuration parameters: EnforcedStyle, MinBodyLength.
+# SupportedStyles: skip_modifier_ifs, always
+Style/Next:
+  Exclude:
+    - 'lib/liquid/tags/for.rb'
+
+# Offense count: 4
+# Cop supports --auto-correct.
+# Configuration parameters: AutoCorrect, EnforcedStyle.
+# SupportedStyles: predicate, comparison
+Style/NumericPredicate:
+  Exclude:
+    - 'spec/**/*'
+    - 'lib/liquid/context.rb'
+    - 'lib/liquid/forloop_drop.rb'
+    - 'lib/liquid/standardfilters.rb'
+    - 'lib/liquid/tablerowloop_drop.rb'
+
+# Offense count: 14
+# Cop supports --auto-correct.
+# Configuration parameters: PreferredDelimiters.
+Style/PercentLiteralDelimiters:
+  Exclude:
+    - 'lib/liquid/tags/if.rb'
+    - 'liquid.gemspec'
+    - 'test/integration/assign_test.rb'
+    - 'test/integration/standard_filter_test.rb'
+
+# Offense count: 1
+# Cop supports --auto-correct.
+Style/RedundantSelf:
+  Exclude:
+    - 'lib/liquid/strainer.rb'
+
+# Offense count: 9
+# Cop supports --auto-correct.
+# Configuration parameters: AllowAsExpressionSeparator.
+Style/Semicolon:
+  Exclude:
+    - 'test/integration/error_handling_test.rb'
+    - 'test/integration/template_test.rb'
+    - 'test/unit/context_unit_test.rb'
+
+# Offense count: 7
+# Cop supports --auto-correct.
+# Configuration parameters: MinSize.
+# SupportedStyles: percent, brackets
+Style/SymbolArray:
+  EnforcedStyle: brackets
+
+# Offense count: 2
+# Cop supports --auto-correct.
+# Configuration parameters: EnforcedStyle, AllowSafeAssignment.
+# SupportedStyles: require_parentheses, require_no_parentheses, require_parentheses_when_complex
+Style/TernaryParentheses:
+  Exclude:
+    - 'lib/liquid/context.rb'
+    - 'lib/liquid/utils.rb'
+
+# Offense count: 2
+# Cop supports --auto-correct.
+Style/UnneededPercentQ:
+  Exclude:
+    - 'test/integration/error_handling_test.rb'
+
+# Offense count: 1
+# Cop supports --auto-correct.
+Style/WhileUntilModifier:
+  Exclude:
+    - 'lib/liquid/tags/case.rb'
+
+# Offense count: 640
+# Configuration parameters: AllowHeredoc, AllowURI, URISchemes, IgnoreCopDirectives, IgnoredPatterns.
+# URISchemes: http, https
+Metrics/LineLength:
+  Max: 294

.travis.yml

@@ -0,0 +1,31 @@
+language: ruby
+
+rvm:
+  - 2.1
+  - 2.2
+  - 2.3
+  - 2.4
+  - 2.5
+  - ruby-head
+  - jruby-head
+#  - rbx-2
+
+sudo: false
+
+addons:
+  apt:
+    packages:
+    - libgmp3-dev
+
+matrix:
+  allow_failures:
+    - rvm: ruby-head
+    - rvm: jruby-head
+
+install:
+  - bundle install
+
+script: bundle exec rake
+
+notifications:
+  disable: true

CHANGELOG

@@ -1,46 +0,0 @@
-* Make context and assign work the same
-
-* Ruby 1.9.1 bugfixes
-
-* Fix LiquidView for Rails 2.2. Fix local assigns for all versions of Rails
-
-* Fixed gem install rake task
-* Improve Error encapsulation in liquid by maintaining a own set of exceptions instead of relying on ruby build ins
-
-* Added If with or / and expressions
-
-* Implemented .to_liquid for all objects which can be passed to liquid like Strings Arrays Hashes Numerics and Booleans. To export new objects to liquid just implement .to_liquid on them and return objects which themselves have .to_liquid methods.
-
-* Added more tags to standard library
-
-* Added include tag ( like partials in rails )
-
-* [...] Gazillion of detail improvements
-
-* Added strainers as filter hosts for better security [Tobias Luetke]
-
-* Fixed that rails integration would call filter with the wrong "self" [Michael Geary]
-
-* Fixed bad error reporting when a filter called a method which doesn't exist. Liquid told you that it couldn't find the filter which was obviously misleading [Tobias Luetke]
-
-* Removed count helper from standard lib. use size [Tobias Luetke]
-
-* Fixed bug with string filter parameters failing to tolerate commas in strings. [Paul Hammond]
-
-* Improved filter parameters. Filter parameters are now context sensitive; Types are resolved according to the rules of the context. Multiple parameters are now separated by the Liquid::ArgumentSeparator: , by default [Paul Hammond]
-
-  {{ 'Typo' | link_to: 'http://typo.leetsoft.com', 'Typo - a modern weblog engine' }}
-
-
-* Added Liquid::Drop. A base class which you can use for exporting proxy objects to liquid which can acquire more data when used in liquid. [Tobias Luetke]
-
-  class ProductDrop < Liquid::Drop
-    def top_sales
-       Shop.current.products.find(:all, :order => 'sales', :limit => 10 )
-    end
-  end
-  t = Liquid::Template.parse( ' {% for product in product.top_sales %} {{ product.name }} {% endfor %} '  )
-  t.render('product' => ProductDrop.new )
-
-
-* Added filter parameters support. Example: {{ date | format_date: "%Y" }} [Paul Hammond]

CONTRIBUTING.md

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+# How to contribute
+
+## Things we will merge
+
+* Bugfixes
+* Performance improvements
+* Features that are likely to be useful to the majority of Liquid users
+
+## Things we won't merge
+
+* Code that introduces considerable performance degrations
+* Code that touches performance-critical parts of Liquid and comes without benchmarks
+* Features that are not important for most people (we want to keep the core Liquid code small and tidy)
+* Features that can easily be implemented on top of Liquid (for example as a custom filter or custom filesystem)
+* Code that does not include tests
+* Code that breaks existing tests
+
+## Workflow
+
+* Fork the Liquid repository
+* Create a new branch in your fork
+* If it makes sense, add tests for your code and/or run a performance benchmark
+* Make sure all tests pass (`bundle exec rake`)
+* Create a pull request
+

Gemfile

@@ -0,0 +1,23 @@
+source 'https://rubygems.org'
+git_source(:github) do |repo_name|
+  "https://github.com/#{repo_name}.git"
+end
+
+gemspec
+
+group :benchmark, :test do
+  gem 'benchmark-ips'
+  gem 'memory_profiler'
+
+  install_if -> { RUBY_PLATFORM !~ /mingw|mswin|java/ } do
+    gem 'stackprof'
+  end
+end
+
+group :test do
+  gem 'rubocop', '~> 0.53.0'
+
+  platform :mri do
+    gem 'liquid-c', github: 'Shopify/liquid-c', ref: '9168659de45d6d576fce30c735f857e597fa26f6'
+  end
+end

History.md

@@ -0,0 +1,288 @@
+# Liquid Change Log
+
+## 4.0.3 / 2019-03-12
+
+### Fixed
+* Fix break and continue tags inside included templates in loops (#1072) [Justin Li]
+
+## 4.0.2 / 2019-03-08
+
+### Changed
+* Add `where` filter (#1026) [Samuel Doiron]
+* Add `ParseTreeVisitor` to iterate the Liquid AST (#1025) [Stephen Paul Weber]
+* Improve `strip_html` performance (#1032) [printercu]
+
+### Fixed
+* Add error checking for invalid combinations of inputs to sort, sort_natural, where, uniq, map, compact filters (#1059) [Garland Zhang]
+* Validate the character encoding in url_decode (#1070) [Clayton Smith]
+
+## 4.0.1 / 2018-10-09
+
+### Changed
+* Add benchmark group in Gemfile (#855) [Jerry Liu]
+* Allow benchmarks to benchmark render by itself (#851) [Jerry Liu]
+* Avoid calling `line_number` on String node when rescuing a render error. (#860) [Dylan Thacker-Smith]
+* Avoid duck typing to detect whether to call render on a node. [Dylan Thacker-Smith]
+* Clarify spelling of `reversed` on `for` block tag (#843) [Mark Crossfield]
+* Replace recursion with loop to avoid potential stack overflow from malicious input (#891, #892) [Dylan Thacker-Smith]
+* Limit block tag nesting to 100 (#894) [Dylan Thacker-Smith]
+* Replace `assert_equal nil` with `assert_nil` (#895) [Dylan Thacker-Smith]
+* Remove Spy Gem (#896) [Dylan Thacker-Smith]
+* Add `collection_name` and `variable_name` reader to `For` block (#909)
+* Symbols render as strings (#920) [Justin Li]
+* Remove default value from Hash objects (#932) [Maxime Bedard]
+* Remove one level of nesting (#944) [Dylan Thacker-Smith]
+* Update Rubocop version (#952) [Justin Li]
+* Add `at_least` and `at_most` filters (#954, #958) [Nithin Bekal]
+* Add a regression test for a liquid-c trim mode bug (#972) [Dylan Thacker-Smith]
+* Use https rather than git protocol to fetch liquid-c [Dylan Thacker-Smith]
+* Add tests against Ruby 2.4 (#963) and 2.5 (#981)
+* Replace RegExp literals with constants (#988) [Ashwin Maroli]
+* Replace unnecessary `#each_with_index` with `#each` (#992) [Ashwin Maroli]
+* Improve the unexpected end delimiter message for block tags. (#1003) [Dylan Thacker-Smith]
+* Refactor and optimize rendering (#1005) [Christopher Aue]
+* Add installation instruction (#1006) [Ben Gift]
+* Remove Circle CI (#1010)
+* Rename deprecated `BigDecimal.new` to `BigDecimal` (#1024) [Koichi ITO]
+* Rename deprecated Rubocop name (#1027) [Justin Li]
+
+### Fixed
+* Handle `join` filter on non String joiners (#857) [Richard Monette]
+* Fix duplicate inclusion condition logic error of `Liquid::Strainer.add_filter` method (#861)
+* Fix `escape`, `url_encode`, `url_decode` not handling non-string values (#898) [Thierry Joyal]
+* Fix raise when variable is defined but nil when using `strict_variables` [Pascal Betz]
+* Fix `sort` and `sort_natural` to handle arrays with nils (#930) [Eric Chan]
+
+## 4.0.0 / 2016-12-14 / branch "4-0-stable"
+
+### Changed
+* Render an opaque internal error by default for non-Liquid::Error (#835) [Dylan Thacker-Smith]
+* Ruby 2.0 support dropped (#832) [Dylan Thacker-Smith]
+* Add to_number Drop method to allow custom drops to work with number filters (#731)
+* Add strict_variables and strict_filters options to detect undefined references (#691)
+* Improve loop performance (#681) [Florian Weingarten]
+* Rename Drop method `before_method` to `liquid_method_missing` (#661) [Thierry Joyal]
+* Add url_decode filter to invert url_encode (#645) [Larry Archer]
+* Add global_filter to apply a filter to all output (#610) [Loren Hale]
+* Add compact filter (#600) [Carson Reinke]
+* Rename deprecated "has_key?" and "has_interrupt?" methods (#593) [Florian Weingarten]
+* Include template name with line numbers in render errors (574) [Dylan Thacker-Smith]
+* Add sort_natural filter (#554) [Martin Hanzel]
+* Add forloop.parentloop as a reference to the parent loop (#520) [Justin Li]
+* Block parsing moved to BlockBody class (#458) [Dylan Thacker-Smith]
+* Add concat filter to concatenate arrays (#429) [Diogo Beato]
+* Ruby 1.9 support dropped (#491) [Justin Li]
+* Liquid::Template.file_system's read_template_file method is no longer passed the context. (#441) [James Reid-Smith]
+* Remove `liquid_methods` (See https://github.com/Shopify/liquid/pull/568 for replacement)
+* Liquid::Template.register_filter raises when the module overrides registered public methods as private or protected (#705) [Gaurav Chande]
+
+### Fixed
+
+* Fix variable names being detected as an operator when starting with contains (#788) [Michael Angell]
+* Fix include tag used with strict_variables (#828) [QuickPay]
+* Fix map filter when value is a Proc (#672) [Guillaume Malette]
+* Fix truncate filter when value is not a string (#672) [Guillaume Malette]
+* Fix behaviour of escape filter when input is nil (#665) [Tanel Jakobsoo]
+* Fix sort filter behaviour with empty array input (#652) [Marcel Cary]
+* Fix test failure under certain timezones (#631) [Dylan Thacker-Smith]
+* Fix bug in uniq filter (#595) [Florian Weingarten]
+* Fix bug when "blank" and "empty" are used as variable names (#592) [Florian Weingarten]
+* Fix condition parse order in strict mode (#569) [Justin Li]
+* Fix naming of the "context variable" when dynamically including a template (#559) [Justin Li]
+* Gracefully accept empty strings in the date filter (#555) [Loren Hale]
+* Fix capturing into variables with a hyphen in the name (#505) [Florian Weingarten]
+* Fix case sensitivity regression in date standard filter (#499) [Kelley Reynolds]
+* Disallow filters with no variable in strict mode (#475) [Justin Li]
+* Disallow variable names in the strict parser that are not valid in the lax parser (#463) [Justin Li]
+* Fix BlockBody#warnings taking exponential time to compute (#486) [Justin Li]
+
+## 3.0.5 / 2015-07-23 / branch "3-0-stable"
+
+* Fix test failure under certain timezones [Dylan Thacker-Smith]
+
+## 3.0.4 / 2015-07-17
+
+* Fix chained access to multi-dimensional hashes [Florian Weingarten]
+
+## 3.0.3 / 2015-05-28
+
+* Fix condition parse order in strict mode (#569) [Justin Li]
+
+## 3.0.2 / 2015-04-24
+
+* Expose VariableLookup private members (#551) [Justin Li]
+* Documentation fixes
+
+## 3.0.1 / 2015-01-23
+
+* Remove duplicate `index0` key in TableRow tag (#502) [Alfred Xing]
+
+## 3.0.0 / 2014-11-12
+
+* Removed Block#end_tag. Instead, override parse with `super` followed by your code. See #446 [Dylan Thacker-Smith]
+* Fixed condition with wrong data types (#423) [Bogdan Gusiev]
+* Add url_encode to standard filters (#421) [Derrick Reimer]
+* Add uniq to standard filters [Florian Weingarten]
+* Add exception_handler feature (#397) and #254 [Bogdan Gusiev, Florian Weingarten]
+* Optimize variable parsing to avoid repeated regex evaluation during template rendering #383 [Jason Hiltz-Laforge]
+* Optimize checking for block interrupts to reduce object allocation #380 [Jason Hiltz-Laforge]
+* Properly set context rethrow_errors on render! #349 [Thierry Joyal]
+* Fix broken rendering of variables which are equal to false (#345) [Florian Weingarten]
+* Remove ActionView template handler [Dylan Thacker-Smith]
+* Freeze lots of string literals for new Ruby 2.1 optimization (#297) [Florian Weingarten]
+* Allow newlines in tags and variables (#324) [Dylan Thacker-Smith]
+* Tag#parse is called after initialize, which now takes options instead of tokens as the 3rd argument. See #321 [Dylan Thacker-Smith]
+* Raise `Liquid::ArgumentError` instead of `::ArgumentError` when filter has wrong number of arguments #309 [Bogdan Gusiev]
+* Add a to_s default for liquid drops (#306) [Adam Doeler]
+* Add strip, lstrip, and rstrip to standard filters [Florian Weingarten]
+* Make if, for & case tags return complete and consistent nodelists (#250) [Nick Jones]
+* Prevent arbitrary method invocation on condition objects (#274) [Dylan Thacker-Smith]
+* Don't call to_sym when creating conditions for security reasons (#273) [Bouke van der Bijl]
+* Fix resource counting bug with respond_to?(:length) (#263) [Florian Weingarten]
+* Allow specifying custom patterns for template filenames (#284) [Andrei Gladkyi]
+* Allow drops to optimize loading a slice of elements (#282) [Tom Burns]
+* Support for passing variables to snippets in subdirs (#271) [Joost Hietbrink]
+* Add a class cache to avoid runtime extend calls (#249) [James Tucker]
+* Remove some legacy Ruby 1.8 compatibility code (#276) [Florian Weingarten]
+* Add default filter to standard filters (#267) [Derrick Reimer]
+* Add optional strict parsing and warn parsing (#235) [Tristan Hume]
+* Add I18n syntax error translation (#241) [Simon Hørup Eskildsen, Sirupsen]
+* Make sort filter work on enumerable drops (#239) [Florian Weingarten]
+* Fix clashing method names in enumerable drops (#238) [Florian Weingarten]
+* Make map filter work on enumerable drops (#233) [Florian Weingarten]
+* Improved whitespace stripping for blank blocks, related to #216 [Florian Weingarten]
+
+## 2.6.3 / 2015-07-23 / branch "2-6-stable"
+
+* Fix test failure under certain timezones [Dylan Thacker-Smith]
+
+## 2.6.2 / 2015-01-23
+
+* Remove duplicate hash key [Parker Moore]
+
+## 2.6.1 / 2014-01-10
+
+Security fix, cherry-picked from master (4e14a65):
+* Don't call to_sym when creating conditions for security reasons (#273) [Bouke van der Bijl]
+* Prevent arbitrary method invocation on condition objects (#274) [Dylan Thacker-Smith]
+
+## 2.6.0 / 2013-11-25
+
+IMPORTANT: Liquid 2.6 is going to be the last version of Liquid which maintains explicit Ruby 1.8 compatability.
+The following releases will only be tested against Ruby 1.9 and Ruby 2.0 and are likely to break on Ruby 1.8.
+
+* Bugfix for #106: fix example servlet [gnowoel]
+* Bugfix for #97: strip_html filter supports multi-line tags [Jo Liss]
+* Bugfix for #114: strip_html filter supports style tags [James Allardice]
+* Bugfix for #117: 'now' support for date filter in Ruby 1.9 [Notre Dame Webgroup]
+* Bugfix for #166: truncate filter on UTF-8 strings with Ruby 1.8 [Florian Weingarten]
+* Bugfix for #204: 'raw' parsing bug [Florian Weingarten]
+* Bugfix for #150: 'for' parsing bug [Peter Schröder]
+* Bugfix for #126: Strip CRLF in strip_newline [Peter Schröder]
+* Bugfix for #174, "can't convert Fixnum into String" for "replace" [jsw0528]
+* Allow a Liquid::Drop to be passed into Template#render [Daniel Huckstep]
+* Resource limits [Florian Weingarten]
+* Add reverse filter [Jay Strybis]
+* Add utf-8 support
+* Use array instead of Hash to keep the registered filters [Tasos Stathopoulos]
+* Cache tokenized partial templates [Tom Burns]
+* Avoid warnings in Ruby 1.9.3 [Marcus Stollsteimer]
+* Better documentation for 'include' tag (closes #163) [Peter Schröder]
+* Use of BigDecimal on filters to have better precision (closes #155) [Arthur Nogueira Neves]
+
+## 2.5.5 / 2014-01-10 / branch "2-5-stable"
+
+Security fix, cherry-picked from master (4e14a65):
+* Don't call to_sym when creating conditions for security reasons (#273) [Bouke van der Bijl]
+* Prevent arbitrary method invocation on condition objects (#274) [Dylan Thacker-Smith]
+
+## 2.5.4 / 2013-11-11
+
+* Fix "can't convert Fixnum into String" for "replace" (#173), [jsw0528]
+
+## 2.5.3 / 2013-10-09
+
+* #232, #234, #237: Fix map filter bugs [Florian Weingarten]
+
+## 2.5.2 / 2013-09-03 / deleted
+
+Yanked from rubygems, as it contained too many changes that broke compatibility. Those changes will be on following major releases.
+
+## 2.5.1 / 2013-07-24
+
+* #230: Fix security issue with map filter, Use invoke_drop in map filter [Florian Weingarten]
+
+## 2.5.0 / 2013-03-06
+
+* Prevent Object methods from being called on drops
+* Avoid symbol injection from liquid
+* Added break and continue statements
+* Fix filter parser for args without space separators
+* Add support for filter keyword arguments
+
+
+## 2.4.0 / 2012-08-03
+
+* Performance improvements
+* Allow filters in `assign`
+* Add `modulo` filter
+* Ruby 1.8, 1.9, and Rubinius compatibility fixes
+* Add support for `quoted['references']` in `tablerow`
+* Add support for Enumerable to `tablerow`
+* `strip_html` filter removes html comments
+
+
+## 2.3.0 / 2011-10-16
+
+* Several speed/memory improvements
+* Numerous bug fixes
+* Added support for MRI 1.9, Rubinius, and JRuby
+* Added support for integer drop parameters
+* Added epoch support to `date` filter
+* New `raw` tag that suppresses parsing
+* Added `else` option to `for` tag
+* New `increment` tag
+* New `split` filter
+
+
+## 2.2.1 / 2010-08-23
+
+* Added support for literal tags
+
+
+## 2.2.0 / 2010-08-22
+
+* Compatible with Ruby 1.8.7, 1.9.1 and 1.9.2-p0
+* Merged some changed made by the community
+
+
+## 1.9.0 / 2008-03-04
+
+* Fixed gem install rake task
+* Improve Error encapsulation in liquid by maintaining a own set of exceptions instead of relying on ruby build ins
+
+
+## Before 1.9.0
+
+* Added If with or / and expressions
+* Implemented .to_liquid for all objects which can be passed to liquid like Strings Arrays Hashes Numerics and Booleans. To export new objects to liquid just implement .to_liquid on them and return objects which themselves have .to_liquid methods.
+* Added more tags to standard library
+* Added include tag ( like partials in rails )
+* [...] Gazillion of detail improvements
+* Added strainers as filter hosts for better security [Tobias Luetke]
+* Fixed that rails integration would call filter with the wrong "self" [Michael Geary]
+* Fixed bad error reporting when a filter called a method which doesn't exist. Liquid told you that it couldn't find the filter which was obviously misleading [Tobias Luetke]
+* Removed count helper from standard lib. use size [Tobias Luetke]
+* Fixed bug with string filter parameters failing to tolerate commas in strings. [Paul Hammond]
+* Improved filter parameters. Filter parameters are now context sensitive; Types are resolved according to the rules of the context. Multiple parameters are now separated by the Liquid::ArgumentSeparator: , by default [Paul Hammond]
+    {{ 'Typo' | link_to: 'http://typo.leetsoft.com', 'Typo - a modern weblog engine' }}
+* Added Liquid::Drop. A base class which you can use for exporting proxy objects to liquid which can acquire more data when used in liquid. [Tobias Luetke]
+
+  class ProductDrop < Liquid::Drop
+    def top_sales
+       Shop.current.products.find(:all, :order => 'sales', :limit => 10 )
+    end
+  end
+  t = Liquid::Template.parse( ' {% for product in product.top_sales %} {{ product.name }} {% endfor %} '  )
+  t.render('product' => ProductDrop.new )
+* Added filter parameters support. Example: {{ date | format_date: "%Y" }} [Paul Hammond]

History.txt

@@ -1,53 +0,0 @@
-2.2.1 / 2010-08-23
-
-* Added support for literal tags
-
-2.2.0 / 2010-08-22
-
-* Compatible with Ruby 1.8.7, 1.9.1 and 1.9.2-p0
-* Merged some changed made by the community
-
-1.9.0 / 2008-03-04
-
-* Fixed gem install rake task
-* Improve Error encapsulation in liquid by maintaining a own set of exceptions instead of relying on ruby build ins
-
-Before 1.9.0
-
-* Added If with or / and expressions
-
-* Implemented .to_liquid for all objects which can be passed to liquid like Strings Arrays Hashes Numerics and Booleans. To export new objects to liquid just implement .to_liquid on them and return objects which themselves have .to_liquid methods. 
-
-* Added more tags to standard library
-
-* Added include tag ( like partials in rails )
-
-* [...] Gazillion of detail improvements
-
-* Added strainers as filter hosts for better security [Tobias Luetke]
-
-* Fixed that rails integration would call filter with the wrong "self" [Michael Geary]
-
-* Fixed bad error reporting when a filter called a method which doesn't exist. Liquid told you that it couldn't find the filter which was obviously misleading [Tobias Luetke]
-
-* Removed count helper from standard lib. use size [Tobias Luetke]
-
-* Fixed bug with string filter parameters failing to tolerate commas in strings. [Paul Hammond]
-
-* Improved filter parameters. Filter parameters are now context sensitive; Types are resolved according to the rules of the context. Multiple parameters are now separated by the Liquid::ArgumentSeparator: , by default [Paul Hammond]
-	
-	{{ 'Typo' | link_to: 'http://typo.leetsoft.com', 'Typo - a modern weblog engine' }}
-	
-
-* Added Liquid::Drop. A base class which you can use for exporting proxy objects to liquid which can acquire more data when used in liquid. [Tobias Luetke] 
-
-  class ProductDrop < Liquid::Drop
-    def top_sales
-       Shop.current.products.find(:all, :order => 'sales', :limit => 10 )
-    end
-  end   
-  t = Liquid::Template.parse( ' {% for product in product.top_sales %} {{ product.name }} {% endfor %} '  )
-  t.render('product' => ProductDrop.new )
-
-
-* Added filter parameters support. Example: {{ date | format_date: "%Y" }} [Paul Hammond]

Manifest.txt

@@ -1,34 +0,0 @@
-CHANGELOG
-History.txt
-MIT-LICENSE
-Manifest.txt
-README.md
-Rakefile
-init.rb
-lib/extras/liquid_view.rb
-lib/liquid.rb
-lib/liquid/block.rb
-lib/liquid/condition.rb
-lib/liquid/context.rb
-lib/liquid/document.rb
-lib/liquid/drop.rb
-lib/liquid/errors.rb
-lib/liquid/extensions.rb
-lib/liquid/file_system.rb
-lib/liquid/htmltags.rb
-lib/liquid/module_ex.rb
-lib/liquid/standardfilters.rb
-lib/liquid/strainer.rb
-lib/liquid/tag.rb
-lib/liquid/tags/assign.rb
-lib/liquid/tags/capture.rb
-lib/liquid/tags/case.rb
-lib/liquid/tags/comment.rb
-lib/liquid/tags/cycle.rb
-lib/liquid/tags/for.rb
-lib/liquid/tags/if.rb
-lib/liquid/tags/ifchanged.rb
-lib/liquid/tags/include.rb
-lib/liquid/tags/unless.rb
-lib/liquid/template.rb
-lib/liquid/variable.rb

README.md

@@ -1,24 +1,33 @@
+[![Build Status](https://api.travis-ci.org/Shopify/liquid.svg?branch=master)](http://travis-ci.org/Shopify/liquid)
+[![Inline docs](http://inch-ci.org/github/Shopify/liquid.svg?branch=master)](http://inch-ci.org/github/Shopify/liquid)
+
 # Liquid template engine
 
+* [Contributing guidelines](CONTRIBUTING.md)
+* [Version history](History.md)
+* [Liquid documentation from Shopify](http://docs.shopify.com/themes/liquid-basics)
+* [Liquid Wiki at GitHub](https://github.com/Shopify/liquid/wiki)
+* [Website](http://liquidmarkup.org/)
+
 ## Introduction
 
-Liquid is a template engine which I wrote for very specific requirements
+Liquid is a template engine which was written with very specific requirements:
 
 * It has to have beautiful and simple markup. Template engines which don't produce good looking markup are no fun to use.
 * It needs to be non evaling and secure. Liquid templates are made so that users can edit them. You don't want to run code on your server which your users wrote.
-* It has to be stateless. Compile and render steps have to be seperate so that the expensive parsing and compiling can be done once and later on you can just render it passing in a hash with local variables and objects.
+* It has to be stateless. Compile and render steps have to be separate so that the expensive parsing and compiling can be done once and later on you can just render it passing in a hash with local variables and objects.
 
-## Why should I use Liquid
+## Why you should use Liquid
 
 * You want to allow your users to edit the appearance of your application but don't want them to run **insecure code on your server**.
-* You want to render templates directly from the database
+* You want to render templates directly from the database.
-* You like smarty (PHP) style template engines
+* You like smarty (PHP) style template engines.
-* You need a template engine which does HTML just as well as emails
+* You need a template engine which does HTML just as well as emails.
-* You don't like the markup of your current templating engine
+* You don't like the markup of your current templating engine.
 
 ## What does it look like?
 
-<code>
+```html
 <ul id="products">
   {% for product in products %}
     <li>
@@ -29,14 +38,71 @@ Liquid is a template engine which I wrote for very specific requirements
     </li>
   {% endfor %}
 </ul>
-</code>
+```
 
 ## How to use Liquid
 
+Install Liquid by adding `gem 'liquid'` to your gemfile.
+
 Liquid supports a very simple API based around the Liquid::Template class.
 For standard use you can just pass it the content of a file and call render with a parameters hash.
 
-<pre>
+```ruby
 @template = Liquid::Template.parse("hi {{name}}") # Parses and compiles the template
 @template.render('name' => 'tobi')                # => "hi tobi"
-</pre>
+```
+
+### Error Modes
+
+Setting the error mode of Liquid lets you specify how strictly you want your templates to be interpreted.
+Normally the parser is very lax and will accept almost anything without error. Unfortunately this can make
+it very hard to debug and can lead to unexpected behaviour. 
+
+Liquid also comes with a stricter parser that can be used when editing templates to give better error messages
+when templates are invalid. You can enable this new parser like this:
+
+```ruby
+Liquid::Template.error_mode = :strict # Raises a SyntaxError when invalid syntax is used
+Liquid::Template.error_mode = :warn # Adds errors to template.errors but continues as normal
+Liquid::Template.error_mode = :lax # The default mode, accepts almost anything.
+```
+
+If you want to set the error mode only on specific templates you can pass `:error_mode` as an option to `parse`:
+```ruby
+Liquid::Template.parse(source, :error_mode => :strict)
+```
+This is useful for doing things like enabling strict mode only in the theme editor.
+
+It is recommended that you enable `:strict` or `:warn` mode on new apps to stop invalid templates from being created.
+It is also recommended that you use it in the template editors of existing apps to give editors better error messages.
+
+### Undefined variables and filters
+
+By default, the renderer doesn't raise or in any other way notify you if some variables or filters are missing, i.e. not passed to the `render` method.
+You can improve this situation by passing `strict_variables: true` and/or `strict_filters: true` options to the `render` method.
+When one of these options is set to true, all errors about undefined variables and undefined filters will be stored in `errors` array of a `Liquid::Template` instance.
+Here are some examples:
+
+```ruby
+template = Liquid::Template.parse("{{x}} {{y}} {{z.a}} {{z.b}}")
+template.render({ 'x' => 1, 'z' => { 'a' => 2 } }, { strict_variables: true })
+#=> '1  2 ' # when a variable is undefined, it's rendered as nil
+template.errors
+#=> [#<Liquid::UndefinedVariable: Liquid error: undefined variable y>, #<Liquid::UndefinedVariable: Liquid error: undefined variable b>]
+```
+
+```ruby
+template = Liquid::Template.parse("{{x | filter1 | upcase}}")
+template.render({ 'x' => 'foo' }, { strict_filters: true })
+#=> '' # when at least one filter in the filter chain is undefined, a whole expression is rendered as nil
+template.errors
+#=> [#<Liquid::UndefinedFilter: Liquid error: undefined filter filter1>]
+```
+
+If you want to raise on a first exception instead of pushing all of them in `errors`, you can use `render!` method:
+
+```ruby
+template = Liquid::Template.parse("{{x}} {{y}}")
+template.render!({ 'x' => 1}, { strict_variables: true })
+#=> Liquid::UndefinedVariable: Liquid error: undefined variable y
+```

Rakefile

@@ -1,43 +1,102 @@
-#!/usr/bin/env ruby
-$:.unshift File.join(File.dirname(__FILE__), 'test') unless $:.include? File.join(File.dirname(__FILE__), 'test')
-
-require 'rubygems'
 require 'rake'
 require 'rake/testtask'
-require 'rake/gempackagetask'
+$LOAD_PATH.unshift File.expand_path("../lib", __FILE__)
+require "liquid/version"
 
-task :default => 'test'
+task default: [:test, :rubocop]
 
-Rake::TestTask.new(:test) do |t|
+desc 'run test suite with default parser'
+Rake::TestTask.new(:base_test) do |t|
   t.libs << '.' << 'lib' << 'test'
-  t.pattern = 'test/lib/**/*_test.rb'
+  t.test_files = FileList['test/{integration,unit}/**/*_test.rb']
   t.verbose = false
 end
 
-gemspec = eval(File.read('liquid.gemspec'))
+desc 'run test suite with warn error mode'
-Rake::GemPackageTask.new(gemspec) do |pkg|
+task :warn_test do
-  pkg.gem_spec = gemspec
+  ENV['LIQUID_PARSER_MODE'] = 'warn'
+  Rake::Task['base_test'].invoke
 end
 
-desc "build the gem and release it to rubygems.org"
+task :rubocop do
-task :release => :gem do
+  require 'rubocop/rake_task'
-  sh "gem push pkg/liquid-#{gemspec.version}.gem"
+  RuboCop::RakeTask.new
+end
+
+desc 'runs test suite with both strict and lax parsers'
+task :test do
+  ENV['LIQUID_PARSER_MODE'] = 'lax'
+  Rake::Task['base_test'].invoke
+
+  ENV['LIQUID_PARSER_MODE'] = 'strict'
+  Rake::Task['base_test'].reenable
+  Rake::Task['base_test'].invoke
+
+  if RUBY_ENGINE == 'ruby'
+    ENV['LIQUID-C'] = '1'
+
+    ENV['LIQUID_PARSER_MODE'] = 'lax'
+    Rake::Task['base_test'].reenable
+    Rake::Task['base_test'].invoke
+
+    ENV['LIQUID_PARSER_MODE'] = 'strict'
+    Rake::Task['base_test'].reenable
+    Rake::Task['base_test'].invoke
+  end
+end
+
+task gem: :build
+task :build do
+  system "gem build liquid.gemspec"
+end
+
+task install: :build do
+  system "gem install liquid-#{Liquid::VERSION}.gem"
+end
+
+task release: :build do
+  system "git tag -a v#{Liquid::VERSION} -m 'Tagging #{Liquid::VERSION}'"
+  system "git push --tags"
+  system "gem push liquid-#{Liquid::VERSION}.gem"
+  system "rm liquid-#{Liquid::VERSION}.gem"
+end
+
+namespace :benchmark do
+  desc "Run the liquid benchmark with lax parsing"
+  task :run do
+    ruby "./performance/benchmark.rb lax"
+  end
+
+  desc "Run the liquid benchmark with strict parsing"
+  task :strict do
+    ruby "./performance/benchmark.rb strict"
+  end
 end
 
 namespace :profile do
-
+  desc "Run the liquid profile/performance coverage"
-  task :default => [:run]
-
-  desc "Run the liquid profile/perforamce coverage"
   task :run do
-
+    ruby "./performance/profile.rb"
-    ruby "performance/shopify.rb"
-
   end
 
-  desc "Run KCacheGrind"
+  desc "Run the liquid profile/performance coverage with strict parsing"
-  task :grind => :run  do
+  task :strict do
-    system "kcachegrind /tmp/liquid.rubyprof_calltreeprinter.txt"
+    ruby "./performance/profile.rb strict"
+  end
 end
 
+namespace :memory_profile do
+  desc "Run memory profiler"
+  task :run do
+    ruby "./performance/memory_profile.rb"
+  end
+end
+
+desc "Run example"
+task :example do
+  ruby "-w -d -Ilib example/server/server.rb"
+end
+
+task :console do
+  exec 'irb -I lib -r liquid'
 end

example/server/example_servlet.rb

@@ -17,13 +17,12 @@ module ProductsFilter
 end
 
 class Servlet < LiquidServlet
-  
   def index
     { 'date' => Time.now }
   end
 
   def products
-    { 'products' => products_list, 'section' => 'Snowboards', 'cool_products' => true}    
+    { 'products' => products_list, 'more_products' => more_products_list, 'description' => description, 'section' => 'Snowboards', 'cool_products' => true }
   end
 
   private
@@ -34,4 +33,12 @@ class Servlet < LiquidServlet
      { 'name' => 'Arbor Diamond', 'price' => 59900, 'description' => 'the *arbor diamond* is a made up product because im obsessed with arbor and have no creativity' }]
   end
 
+  def more_products_list
+    [{ 'name' => 'Arbor Catalyst', 'price' => 39900, 'description' => 'the *arbor catalyst* is an advanced drop-through for freestyle and flatground performance and versatility' },
+     { 'name' => 'Arbor Fish', 'price' => 40000, 'description' => 'the *arbor fish* is a compact pin that features an extended wheelbase and time-honored teardrop shape' }]
+  end
+
+  def description
+    "List of Products ~ This is a list of products with price and description."
+  end
 end

example/server/liquid_servlet.rb

@@ -1,5 +1,4 @@
 class LiquidServlet < WEBrick::HTTPServlet::AbstractServlet
-
   def do_GET(req, res)
     handle(:get, req, res)
   end
@@ -11,18 +10,19 @@ class LiquidServlet < WEBrick::HTTPServlet::AbstractServlet
   private
 
   def handle(type, req, res)
-    @request, @response = req, res
+    @request = req
+    @response = res
 
-    @request.path_info =~ /(\w+)$/
+    @request.path_info =~ /(\w+)\z/
     @action = $1 || 'index'
     @assigns = send(@action) if respond_to?(@action)
 
     @response['Content-Type'] = "text/html"
     @response.status = 200
-    @response.body = Liquid::Template.parse(read_template).render(@assigns, :filters => [ProductsFilter])      
+    @response.body = Liquid::Template.parse(read_template).render(@assigns, filters: [ProductsFilter])
   end
 
   def read_template(filename = @action)
-    File.read( File.dirname(__FILE__) + "/templates/#{filename}.liquid" )
+    File.read("#{__dir__}/templates/#{filename}.liquid")
   end
 end

example/server/server.rb

@@ -1,12 +1,12 @@
 require 'webrick'
 require 'rexml/document'
 
-require File.dirname(__FILE__) + '/../../lib/liquid'
+require_relative '../../lib/liquid'
-require File.dirname(__FILE__) + '/liquid_servlet'
+require_relative 'liquid_servlet'
-require File.dirname(__FILE__) + '/example_servlet'
+require_relative 'example_servlet'
 
 # Setup webrick
-server = WEBrick::HTTPServer.new( :Port => ARGV[1] || 3000 )
+server = WEBrick::HTTPServer.new(Port: ARGV[1] || 3000)
 server.mount('/', Servlet)
 trap("INT"){ server.shutdown }
 server.start

example/server/templates/index.liquid

@@ -3,4 +3,4 @@
 <p>It is {{date}}</p>
 
 
-<p>Check out the <a href="http://localhost:3000/products">Products</a> screen </p>
+<p>Check out the <a href="/products">Products</a> screen </p>

example/server/templates/products.liquid

@@ -16,8 +16,12 @@
   </head>
 
   <body>
+    {% assign all_products = products | concat: more_products  %}
+    <h1>{{ description | split: '~' | first }}</h1>
 
-	  <h1>There are currently {{products | count}} products in the {{section}} catalog</h1>
+    <h2>{{ description | split: '~' | last }}</h2>
+
+    <h2>There are currently {{all_products | count}} products in the {{section}} catalog</h2>
 
     {% if cool_products %}
       Cool products :)
@@ -27,7 +31,7 @@
 
     <ul id="products">
 
-      {% for product in products %}
+      {% for product in all_products %}
         <li>
           <h2>{{product.name}}</h2>
           Only {{product.price | price }}

init.rb

@@ -1,8 +0,0 @@
-require 'liquid'
-require 'extras/liquid_view'
-
-if defined? ActionView::Template and ActionView::Template.respond_to? :register_template_handler
-  ActionView::Template
-else
-  ActionView::Base
-end.register_template_handler(:liquid, LiquidView)

lib/extras/liquid_view.rb

@@ -1,51 +0,0 @@
-# LiquidView is a action view extension class. You can register it with rails
-# and use liquid as an template system for .liquid files
-#
-# Example
-# 
-#   ActionView::Base::register_template_handler :liquid, LiquidView
-class LiquidView
-  PROTECTED_ASSIGNS = %w( template_root response _session template_class action_name request_origin session template
-                          _response url _request _cookies variables_added _flash params _headers request cookies
-                          ignore_missing_templates flash _params logger before_filter_chain_aborted headers )
-  PROTECTED_INSTANCE_VARIABLES = %w( @_request @controller @_first_render @_memoized__pick_template @view_paths 
-                                     @helpers @assigns_added @template @_render_stack @template_format @assigns )
-  
-  def self.call(template)
-    "LiquidView.new(self).render(template, local_assigns)"
-  end
-
-  def initialize(view)
-    @view = view
-  end
-  
-  def render(template, local_assigns = nil)
-    @view.controller.headers["Content-Type"] ||= 'text/html; charset=utf-8'
-    
-    # Rails 2.2 Template has source, but not locals
-    if template.respond_to?(:source) && !template.respond_to?(:locals)
-      assigns = (@view.instance_variables - PROTECTED_INSTANCE_VARIABLES).inject({}) do |hash, ivar|
-                  hash[ivar[1..-1]] = @view.instance_variable_get(ivar)
-                  hash
-                end
-    else
-      assigns = @view.assigns.reject{ |k,v| PROTECTED_ASSIGNS.include?(k) }
-    end
-    
-    source = template.respond_to?(:source) ? template.source : template
-    local_assigns = (template.respond_to?(:locals) ? template.locals : local_assigns) || {}
-    
-    if content_for_layout = @view.instance_variable_get("@content_for_layout")
-      assigns['content_for_layout'] = content_for_layout
-    end
-    assigns.merge!(local_assigns.stringify_keys)
-    
-    liquid = Liquid::Template.parse(source)
-    liquid.render(assigns, :filters => [@view.controller.master_helper_module], :registers => {:action_view => @view, :controller => @view.controller})
-  end
-
-  def compilable?
-    false
-  end
-
-end

lib/liquid.rb

@@ -19,13 +19,12 @@
 # OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 # WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
-$LOAD_PATH.unshift(File.dirname(__FILE__))
-
 module Liquid
   FilterSeparator             = /\|/
-  ArgumentSeparator           = ','
+  ArgumentSeparator           = ','.freeze
-  FilterArgumentSeparator     = ':'
+  FilterArgumentSeparator     = ':'.freeze
-  VariableAttributeSeparator  = '.'
+  VariableAttributeSeparator  = '.'.freeze
+  WhitespaceControl           = '-'.freeze
   TagStart                    = /\{\%/
   TagEnd                      = /\%\}/
   VariableSignature           = /\(?[\w\-\.\[\]]\)?/
@@ -34,36 +33,48 @@ module Liquid
   VariableEnd                 = /\}\}/
   VariableIncompleteEnd       = /\}\}?/
   QuotedString                = /"[^"]*"|'[^']*'/
-  QuotedFragment              = /#{QuotedString}|(?:[^\s,\|'"]|#{QuotedString})+/
+  QuotedFragment              = /#{QuotedString}|(?:[^\s,\|'"]|#{QuotedString})+/o
-  StrictQuotedFragment        = /"[^"]+"|'[^']+'|[^\s,\|,\:,\,]+/
+  TagAttributes               = /(\w+)\s*\:\s*(#{QuotedFragment})/o
-  FirstFilterArgument         = /#{FilterArgumentSeparator}(?:#{StrictQuotedFragment})/
+  AnyStartingTag              = /#{TagStart}|#{VariableStart}/o
-  OtherFilterArgument         = /#{ArgumentSeparator}(?:#{StrictQuotedFragment})/
+  PartialTemplateParser       = /#{TagStart}.*?#{TagEnd}|#{VariableStart}.*?#{VariableIncompleteEnd}/om
-  SpacelessFilter             = /^(?:'[^']+'|"[^"]+"|[^'"])*#{FilterSeparator}(?:#{StrictQuotedFragment})(?:#{FirstFilterArgument}(?:#{OtherFilterArgument})*)?/
+  TemplateParser              = /(#{PartialTemplateParser}|#{AnyStartingTag})/om
-  Expression                  = /(?:#{QuotedFragment}(?:#{SpacelessFilter})*)/
+  VariableParser              = /\[[^\]]+\]|#{VariableSegment}+\??/o
-  TagAttributes               = /(\w+)\s*\:\s*(#{QuotedFragment})/
+
-  AnyStartingTag              = /\{\{|\{\%/
+  singleton_class.send(:attr_accessor, :cache_classes)
-  PartialTemplateParser       = /#{TagStart}.*?#{TagEnd}|#{VariableStart}.*?#{VariableIncompleteEnd}/
+  self.cache_classes = true
-  TemplateParser              = /(#{PartialTemplateParser}|#{AnyStartingTag})/
-  VariableParser              = /\[[^\]]+\]|#{VariableSegment}+\??/
-  LiteralShorthand            = /^(?:\{\{\{\s?)(.*?)(?:\s*\}\}\})$/
 end
 
+require "liquid/version"
+require 'liquid/parse_tree_visitor'
+require 'liquid/lexer'
+require 'liquid/parser'
+require 'liquid/i18n'
 require 'liquid/drop'
+require 'liquid/tablerowloop_drop'
+require 'liquid/forloop_drop'
 require 'liquid/extensions'
 require 'liquid/errors'
+require 'liquid/interrupts'
 require 'liquid/strainer'
+require 'liquid/expression'
 require 'liquid/context'
+require 'liquid/parser_switching'
 require 'liquid/tag'
 require 'liquid/block'
+require 'liquid/block_body'
 require 'liquid/document'
 require 'liquid/variable'
+require 'liquid/variable_lookup'
+require 'liquid/range_lookup'
 require 'liquid/file_system'
+require 'liquid/resource_limits'
 require 'liquid/template'
-require 'liquid/htmltags'
 require 'liquid/standardfilters'
 require 'liquid/condition'
-require 'liquid/module_ex'
+require 'liquid/utils'
+require 'liquid/tokenizer'
+require 'liquid/parse_context'
 
 # Load all the tags of the standard library
 #
-Dir[File.dirname(__FILE__) + '/liquid/tags/*.rb'].each { |f| require f }
+Dir["#{__dir__}/liquid/tags/*.rb"].each { |f| require f }

lib/liquid/block.rb

@@ -1,101 +1,77 @@
 module Liquid
-
   class Block < Tag
-    IsTag             = /^#{TagStart}/
+    MAX_DEPTH = 100
-    IsVariable        = /^#{VariableStart}/
+
-    FullToken         = /^#{TagStart}\s*(\w+)\s*(.*)?#{TagEnd}$/
+    def initialize(tag_name, markup, options)
-    ContentOfVariable = /^#{VariableStart}(.*)#{VariableEnd}$/
+      super
+      @blank = true
+    end
 
     def parse(tokens)
-      @nodelist ||= []
+      @body = BlockBody.new
-      @nodelist.clear
+      while parse_body(@body, tokens)
-
+      end
-      while token = tokens.shift
-
-        case token
-        when IsTag
-          if token =~ FullToken
-
-            # if we found the proper block delimitor just end parsing here and let the outer block
-            # proceed
-            if block_delimiter == $1
-              end_tag
-              return
     end
 
-            # fetch the tag from registered blocks
+    def render(context)
-            if tag = Template.tags[$1]
+      @body.render(context)
-              @nodelist << tag.new($1, $2, tokens)
+    end
+
+    def blank?
+      @blank
+    end
+
+    def nodelist
+      @body.nodelist
+    end
+
+    def unknown_tag(tag, _params, _tokens)
+      if tag == 'else'.freeze
+        raise SyntaxError.new(parse_context.locale.t("errors.syntax.unexpected_else".freeze,
+          block_name: block_name))
+      elsif tag.start_with?('end'.freeze)
+        raise SyntaxError.new(parse_context.locale.t("errors.syntax.invalid_delimiter".freeze,
+          tag: tag,
+          block_name: block_name,
+          block_delimiter: block_delimiter))
       else
-              # this tag is not registered with the system
+        raise SyntaxError.new(parse_context.locale.t("errors.syntax.unknown_tag".freeze, tag: tag))
-              # pass it to the current block for special handling or error reporting
-              unknown_tag($1, $2, tokens)
       end
-          else
-            raise SyntaxError, "Tag '#{token}' was not properly terminated with regexp: #{TagEnd.inspect} "
-          end
-        when IsVariable
-          @nodelist << create_variable(token)
-        when ''
-          # pass
-        else
-          @nodelist << token
-        end
-      end
-
-      # Make sure that its ok to end parsing in the current block.
-      # Effectively this method will throw and exception unless the current block is
-      # of type Document
-      assert_missing_delimitation!
-    end
-
-    def end_tag
-    end
-
-    def unknown_tag(tag, params, tokens)
-      case tag
-      when 'else'
-        raise SyntaxError, "#{block_name} tag does not expect else tag"
-      when 'end'
-        raise SyntaxError, "'end' is not a valid delimiter for #{block_name} tags. use #{block_delimiter}"
-      else
-        raise SyntaxError, "Unknown tag '#{tag}'"
-      end
-    end
-
-    def block_delimiter
-      "end#{block_name}"
     end
 
     def block_name
       @tag_name
     end
 
-    def create_variable(token)
+    def block_delimiter
-      token.scan(ContentOfVariable) do |content|
+      @block_delimiter ||= "end#{block_name}"
-        return Variable.new(content.first)
-      end
-      raise SyntaxError.new("Variable '#{token}' was not properly terminated with regexp: #{VariableEnd.inspect} ")
-    end
-
-    def render(context)
-      render_all(@nodelist, context)
     end
 
     protected
 
-    def assert_missing_delimitation!
+    def parse_body(body, tokens)
-      raise SyntaxError.new("#{block_name} tag was never closed")
+      if parse_context.depth >= MAX_DEPTH
+        raise StackLevelError, "Nesting too deep".freeze
+      end
+      parse_context.depth += 1
+      begin
+        body.parse(tokens, parse_context) do |end_tag_name, end_tag_params|
+          @blank &&= body.blank?
+
+          return false if end_tag_name == block_delimiter
+          unless end_tag_name
+            raise SyntaxError.new(parse_context.locale.t("errors.syntax.tag_never_closed".freeze, block_name: block_name))
           end
 
-    def render_all(list, context)
+          # this tag is not registered with the system
-      list.collect do |token|
+          # pass it to the current block for special handling or error reporting
-        begin
+          unknown_tag(end_tag_name, end_tag_params, tokens)
-          token.respond_to?(:render) ? token.render(context) : token
+        end
-        rescue Exception => e
+      ensure
-          context.handle_error(e)
+        parse_context.depth -= 1
-        end
+      end
-      end
+
+      true
     end
   end
 end

lib/liquid/block_body.rb

@@ -0,0 +1,143 @@
+module Liquid
+  class BlockBody
+    FullToken = /\A#{TagStart}#{WhitespaceControl}?\s*(\w+)\s*(.*?)#{WhitespaceControl}?#{TagEnd}\z/om
+    ContentOfVariable = /\A#{VariableStart}#{WhitespaceControl}?(.*?)#{WhitespaceControl}?#{VariableEnd}\z/om
+    WhitespaceOrNothing = /\A\s*\z/
+    TAGSTART = "{%".freeze
+    VARSTART = "{{".freeze
+
+    attr_reader :nodelist
+
+    def initialize
+      @nodelist = []
+      @blank = true
+    end
+
+    def parse(tokenizer, parse_context)
+      parse_context.line_number = tokenizer.line_number
+      while token = tokenizer.shift
+        next if token.empty?
+        case
+        when token.start_with?(TAGSTART)
+          whitespace_handler(token, parse_context)
+          unless token =~ FullToken
+            raise_missing_tag_terminator(token, parse_context)
+          end
+          tag_name = $1
+          markup = $2
+          # fetch the tag from registered blocks
+          unless tag = registered_tags[tag_name]
+            # end parsing if we reach an unknown tag and let the caller decide
+            # determine how to proceed
+            return yield tag_name, markup
+          end
+          new_tag = tag.parse(tag_name, markup, tokenizer, parse_context)
+          @blank &&= new_tag.blank?
+          @nodelist << new_tag
+        when token.start_with?(VARSTART)
+          whitespace_handler(token, parse_context)
+          @nodelist << create_variable(token, parse_context)
+          @blank = false
+        else
+          if parse_context.trim_whitespace
+            token.lstrip!
+          end
+          parse_context.trim_whitespace = false
+          @nodelist << token
+          @blank &&= !!(token =~ WhitespaceOrNothing)
+        end
+        parse_context.line_number = tokenizer.line_number
+      end
+
+      yield nil, nil
+    end
+
+    def whitespace_handler(token, parse_context)
+      if token[2] == WhitespaceControl
+        previous_token = @nodelist.last
+        if previous_token.is_a? String
+          previous_token.rstrip!
+        end
+      end
+      parse_context.trim_whitespace = (token[-3] == WhitespaceControl)
+    end
+
+    def blank?
+      @blank
+    end
+
+    def render(context)
+      output = []
+      context.resource_limits.render_score += @nodelist.length
+
+      idx = 0
+      while node = @nodelist[idx]
+        case node
+        when String
+          check_resources(context, node)
+          output << node
+        when Variable
+          render_node_to_output(node, output, context)
+        when Block
+          render_node_to_output(node, output, context, node.blank?)
+          break if context.interrupt? # might have happened in a for-block
+        when Continue, Break
+          # If we get an Interrupt that means the block must stop processing. An
+          # Interrupt is any command that stops block execution such as {% break %}
+          # or {% continue %}
+          context.push_interrupt(node.interrupt)
+          break
+        else # Other non-Block tags
+          render_node_to_output(node, output, context)
+          break if context.interrupt? # might have happened through an include
+        end
+        idx += 1
+      end
+
+      output.join
+    end
+
+    private
+
+    def render_node_to_output(node, output, context, skip_output = false)
+      node_output = node.render(context)
+      node_output = node_output.is_a?(Array) ? node_output.join : node_output.to_s
+      check_resources(context, node_output)
+      output << node_output unless skip_output
+    rescue MemoryError => e
+      raise e
+    rescue UndefinedVariable, UndefinedDropMethod, UndefinedFilter => e
+      context.handle_error(e, node.line_number)
+      output << nil
+    rescue ::StandardError => e
+      line_number = node.is_a?(String) ? nil : node.line_number
+      output << context.handle_error(e, line_number)
+    end
+
+    def check_resources(context, node_output)
+      context.resource_limits.render_length += node_output.bytesize
+      return unless context.resource_limits.reached?
+      raise MemoryError.new("Memory limits exceeded".freeze)
+    end
+
+    def create_variable(token, parse_context)
+      token.scan(ContentOfVariable) do |content|
+        markup = content.first
+        return Variable.new(markup, parse_context)
+      end
+      raise_missing_variable_terminator(token, parse_context)
+    end
+
+    def raise_missing_tag_terminator(token, parse_context)
+      raise SyntaxError.new(parse_context.locale.t("errors.syntax.tag_termination".freeze, token: token, tag_end: TagEnd.inspect))
+    end
+
+    def raise_missing_variable_terminator(token, parse_context)
+      raise SyntaxError.new(parse_context.locale.t("errors.syntax.variable_termination".freeze, token: token, tag_end: VariableEnd.inspect))
+    end
+
+    def registered_tags
+      Template.tags
+    end
+  end
+end

lib/liquid/condition.rb

@@ -3,53 +3,70 @@ module Liquid
   #
   # Example:
   #
-  #   c = Condition.new('1', '==', '1')
+  #   c = Condition.new(1, '==', 1)
   #   c.evaluate #=> true
   #
   class Condition #:nodoc:
     @@operators = {
-      '==' => lambda { |cond, left, right|  cond.send(:equal_variables, left, right) },
+      '=='.freeze => ->(cond, left, right) {  cond.send(:equal_variables, left, right) },
-      '!=' => lambda { |cond, left, right| !cond.send(:equal_variables, left, right) },
+      '!='.freeze => ->(cond, left, right) { !cond.send(:equal_variables, left, right) },
-      '<>' => lambda { |cond, left, right| !cond.send(:equal_variables, left, right) },
+      '<>'.freeze => ->(cond, left, right) { !cond.send(:equal_variables, left, right) },
-      '<'  => :<,
+      '<'.freeze  => :<,
-      '>'  => :>,
+      '>'.freeze  => :>,
-      '>=' => :>=,
+      '>='.freeze => :>=,
-      '<=' => :<=,
+      '<='.freeze => :<=,
-      'contains' => lambda { |cond, left, right| left && right ? left.include?(right) : false }
+      'contains'.freeze => lambda do |cond, left, right|
+        if left && right && left.respond_to?(:include?)
+          right = right.to_s if left.is_a?(String)
+          left.include?(right)
+        else
+          false
+        end
+      end
     }
 
     def self.operators
       @@operators
     end
 
-    attr_reader :attachment
+    attr_reader :attachment, :child_condition
     attr_accessor :left, :operator, :right
 
     def initialize(left = nil, operator = nil, right = nil)
-      @left, @operator, @right = left, operator, right
+      @left = left
+      @operator = operator
+      @right = right
       @child_relation  = nil
       @child_condition = nil
     end
 
     def evaluate(context = Context.new)
-      result = interpret_condition(left, right, operator, context)
+      condition = self
+      result = nil
+      loop do
+        result = interpret_condition(condition.left, condition.right, condition.operator, context)
 
-      case @child_relation
+        case condition.child_relation
         when :or
-        result || @child_condition.evaluate(context)
+          break if result
         when :and
-        result && @child_condition.evaluate(context)
+          break unless result
         else
-        result
+          break
         end
+        condition = condition.child_condition
+      end
+      result
     end
 
     def or(condition)
-      @child_relation, @child_condition = :or, condition
+      @child_relation = :or
+      @child_condition = condition
     end
 
     def and(condition)
-      @child_relation, @child_condition = :and, condition
+      @child_relation = :and
+      @child_condition = condition
     end
 
     def attach(attachment)
@@ -61,23 +78,27 @@ module Liquid
     end
 
     def inspect
-      "#<Condition #{[@left, @operator, @right].compact.join(' ')}>"
+      "#<Condition #{[@left, @operator, @right].compact.join(' '.freeze)}>"
     end
 
+    protected
+
+    attr_reader :child_relation
+
     private
 
     def equal_variables(left, right)
-      if left.is_a?(Symbol)
+      if left.is_a?(Liquid::Expression::MethodLiteral)
-        if right.respond_to?(left)
+        if right.respond_to?(left.method_name)
-          return right.send(left.to_s)
+          return right.send(left.method_name)
         else
           return nil
         end
       end
 
-      if right.is_a?(Symbol)
+      if right.is_a?(Liquid::Expression::MethodLiteral)
-        if left.respond_to?(right)
+        if left.respond_to?(right.method_name)
-          return left.send(right.to_s)
+          return left.send(right.method_name)
         else
           return nil
         end
@@ -90,31 +111,41 @@ module Liquid
       # If the operator is empty this means that the decision statement is just
       # a single variable. We can just poll this variable from the context and
       # return this as the result.
-      return context[left] if op == nil
+      return context.evaluate(left) if op.nil?
 
-      left, right = context[left], context[right]
+      left = context.evaluate(left)
+      right = context.evaluate(right)
 
-      operation = self.class.operators[op] || raise(ArgumentError.new("Unknown operator #{op}"))
+      operation = self.class.operators[op] || raise(Liquid::ArgumentError.new("Unknown operator #{op}"))
 
       if operation.respond_to?(:call)
         operation.call(self, left, right)
-      elsif left.respond_to?(operation) and right.respond_to?(operation)
+      elsif left.respond_to?(operation) && right.respond_to?(operation) && !left.is_a?(Hash) && !right.is_a?(Hash)
+        begin
           left.send(operation, right)
-      else
+        rescue ::ArgumentError => e
-        nil
+          raise Liquid::ArgumentError.new(e.message)
         end
       end
     end
 
+    class ParseTreeVisitor < Liquid::ParseTreeVisitor
+      def children
+        [
+          @node.left, @node.right,
+          @node.child_condition, @node.attachment
+        ].compact
+      end
+    end
+  end
 
   class ElseCondition < Condition
     def else?
       true
     end
 
-    def evaluate(context)
+    def evaluate(_context)
       true
     end
   end
-
 end

lib/liquid/context.rb

@@ -1,5 +1,4 @@
 module Liquid
-
   # Context keeps the variable stack and resolves variables, as well as keywords
   #
   #   context['variable'] = 'testing'
@@ -13,19 +12,37 @@ module Liquid
   #
   #   context['bob']  #=> nil  class Context
   class Context
-    attr_reader :scopes, :errors, :registers, :environments
+    attr_reader :scope, :errors, :registers, :environments, :resource_limits
+    attr_accessor :exception_renderer, :template_name, :partial, :global_filter, :strict_variables, :strict_filters
 
-    def initialize(environments = {}, outer_scope = {}, registers = {}, rethrow_errors = false)
+    def initialize(environments = {}, outer_scope = {}, registers = {}, rethrow_errors = false, resource_limits = nil)
       @environments     = [environments].flatten
-      @scopes         = [(outer_scope || {})]
+      @scope            = outer_scope || {}
       @registers        = registers
       @errors           = []
-      @rethrow_errors = rethrow_errors
+      @partial          = false
+      @strict_variables = false
+      @resource_limits  = resource_limits || ResourceLimits.new(Template.default_resource_limits)
       squash_instance_assigns_with_environments
+
+      self.exception_renderer = Template.default_exception_renderer
+      if rethrow_errors
+        self.exception_renderer = ->(e) { raise }
+      end
+
+      @interrupts = []
+      @filters = []
+      @global_filter = nil
+
+      @stack_level = 0
+    end
+
+    def warnings
+      @warnings ||= []
     end
 
     def strainer
-      @strainer ||= Strainer.create(self)
+      @strainer ||= Strainer.create(self, @filters)
     end
 
     # Adds filters to this context.
@@ -34,48 +51,44 @@ module Liquid
     # for that
     def add_filters(filters)
       filters = [filters].flatten.compact
-
+      @filters += filters
-      filters.each do |f|
+      @strainer = nil
-        raise ArgumentError, "Expected module but got: #{f.class}" unless f.is_a?(Module)
-        strainer.extend(f)
-      end
     end
 
-    def handle_error(e)
+    def apply_global_filter(obj)
+      global_filter.nil? ? obj : global_filter.call(obj)
+    end
+
+    # are there any not handled interrupts?
+    def interrupt?
+      !@interrupts.empty?
+    end
+
+    # push an interrupt to the stack. this interrupt is considered not handled.
+    def push_interrupt(e)
+      @interrupts.push(e)
+    end
+
+    # pop an interrupt from the stack
+    def pop_interrupt
+      @interrupts.pop
+    end
+
+    def handle_error(e, line_number = nil)
+      e = internal_error unless e.is_a?(Liquid::Error)
+      e.template_name ||= template_name
+      e.line_number ||= line_number
       errors.push(e)
-      raise if @rethrow_errors
+      exception_renderer.call(e).to_s
-
-      case e
-      when SyntaxError
-        "Liquid syntax error: #{e.message}"
-      else
-        "Liquid error: #{e.message}"
-      end
     end
 
     def invoke(method, *args)
-      if strainer.respond_to?(method)
+      strainer.invoke(method, *args).to_liquid
-        strainer.__send__(method, *args)
-      else
-        args.first
-      end
-    end
-
-    # Push new local scope on the stack. use <tt>Context#stack</tt> instead
-    def push(new_scope={})
-      raise StackLevelError, "Nesting too deep" if @scopes.length > 100
-      @scopes.unshift(new_scope)
     end
 
     # Merge a hash of variables in the current local scope
     def merge(new_scopes)
-      @scopes[0].merge!(new_scopes)
+      new_scopes.each { |k, v| self[k] = v }
-    end
-
-    # Pop from the stack. use <tt>Context#stack</tt> instead
-    def pop
-      raise ContextError if @scopes.size == 1
-      @scopes.shift
     end
 
     # Pushes a new local scope on the stack, pops it at the end of the block
@@ -86,37 +99,22 @@ module Liquid
     #   end
     #
     #   context['var]  #=> nil
-    def stack(new_scope={},&block)
+    def stack(*variable_names)
-      result = nil
+      @stack_level += 1
-      push(new_scope)
+      raise StackLevelError, "Nesting too deep".freeze if @stack_level > Block::MAX_DEPTH
 
       begin
-        result = yield
+        yield
       ensure
-        pop
+        @stack_level -= 1
       end
-
-      result
-    end
-
-    def clear_instance_assigns
-      @scopes[0] = {}
     end
 
     # Only allow String, Numeric, Hash, Array, Proc, Boolean or <tt>Liquid::Drop</tt>
     def []=(key, value)
-      @scopes[0][key] = value
+      (@scope[key] ||= [nil]) << value
     end
 
-    def [](key)
-      resolve(key)
-    end
-
-    def has_key?(key)
-      resolve(key) != nil
-    end
-
-    private
     # Look up variable, either resolve directly after considering the name. We can directly handle
     # Strings, digits, floats and booleans (true,false).
     # If no match is made we lookup the variable in the current scope and
@@ -125,125 +123,103 @@ module Liquid
     #
     # Example:
     #   products == empty #=> products.empty?
-      def resolve(key)
+    def [](expression)
-        case key
+      evaluate(Expression.parse(expression))
-        when nil, 'nil', 'null', ''
-          nil
-        when 'true'
-          true
-        when 'false'
-          false
-        when 'blank'
-          :blank?
-        when 'empty' # Single quoted strings
-          :empty?
-        when /^'(.*)'$/ # Double quoted strings
-          $1.to_s
-        when /^"(.*)"$/ # Integer and floats
-          $1.to_s
-        when /^(\d+)$/ # Ranges
-          $1.to_i
-        when /^\((\S+)\.\.(\S+)\)$/ # Floats
-          (resolve($1).to_i..resolve($2).to_i)
-        when /^(\d[\d\.]+)$/
-          $1.to_f
-        else
-          variable(key)
     end
+
+    def unset(key)
+      if @scope[key].size <= 1
+        @scope.delete(key)
+      else
+        @scope[key].pop
+      end
+    end
+
+    def set_root(key, val)
+      @scope[key] ||= []
+      @scope[key][0] = val
+    end
+
+    def set_level(key, val, int)
+      @scope[key] ||= []
+      @scope[key][int] = val
+    end
+
+    def create_level(key)
+      (@scope[key] ||= [nil]) << nil
+      @scope[key].size - 1
+    end
+
+    def key?(key)
+      self[key] != nil
+    end
+
+    def evaluate(object)
+      object.respond_to?(:evaluate) ? object.evaluate(self) : object
     end
 
     # Fetches an object starting at the local scope and then moving up the hierachy
-      def find_variable(key)
+    def find_variable(key, raise_on_not_found: true)
-        scope = @scopes.find { |s| s.has_key?(key) }
+      trigger = false
+      value = @scope[key]
+      scope = @scope unless value.nil?
+      trigger = true unless value.nil?
 
       if scope.nil?
-          @environments.each do |e|
+        index = @environments.find_index do |e|
-            if variable = lookup_and_evaluate(e, key)
+          variable = lookup_and_evaluate(e, key, raise_on_not_found: raise_on_not_found)
-              scope = e
+          # When lookup returned a value OR there is no value but the lookup also did not raise
-              break
+          # then it is the value we are looking for.
-            end
+          !variable.nil? || @strict_variables && raise_on_not_found
-          end
         end
 
-        scope     ||= @environments.last || @scopes.last
+        scope = @environments[index || -1]
-        variable  ||= lookup_and_evaluate(scope, key)
+      end
+
+      variable ||= lookup_and_evaluate(scope, key, trigger, raise_on_not_found: raise_on_not_found)
 
       variable = variable.to_liquid
       variable.context = self if variable.respond_to?(:context=)
 
-        return variable
+      variable
     end
 
-      # Resolves namespaced queries gracefully.
+    def lookup_and_evaluate(obj, key, trigger = false, raise_on_not_found: true)
-      #
+      if @strict_variables && raise_on_not_found && obj.respond_to?(:key?) && !obj.key?(key)
-      # Example
+        raise Liquid::UndefinedVariable, "undefined variable #{key}"
-      #  @context['hash'] = {"name" => 'tobi'}
-      #  assert_equal 'tobi', @context['hash.name']
-      #  assert_equal 'tobi', @context['hash["name"]']
-      def variable(markup)
-        parts = markup.scan(VariableParser)
-        square_bracketed = /^\[(.*)\]$/
-
-        first_part = parts.shift
-
-        if first_part =~ square_bracketed
-          first_part = resolve($1)
       end
 
-        if object = find_variable(first_part)
+      value = if trigger == true
-
+        obj[key][-1]
-          parts.each do |part|
-            part = resolve($1) if part_resolved = (part =~ square_bracketed)
-
-            # If object is a hash- or array-like object we look for the
-            # presence of the key and if its available we return it
-            if object.respond_to?(:[]) and
-              ((object.respond_to?(:has_key?) and object.has_key?(part)) or
-               (object.respond_to?(:fetch) and part.is_a?(Integer)))
-
-              # if its a proc we will replace the entry with the proc
-              res = lookup_and_evaluate(object, part)
-              object = res.to_liquid
-
-              # Some special cases. If the part wasn't in square brackets and
-              # no key with the same name was found we interpret following calls
-              # as commands and call them on the current object
-            elsif !part_resolved and object.respond_to?(part) and ['size', 'first', 'last'].include?(part)
-
-              object = object.send(part.intern).to_liquid
-
-              # No key was present with the desired value and it wasn't one of the directly supported
-              # keywords either. The only thing we got left is to return nil
       else
-              return nil
+        obj[key]
       end
 
-            # If we are dealing with a drop here we have to
+      if value.is_a?(Proc) && obj.respond_to?(:[]=)
-            object.context = self if object.respond_to?(:context=)
-          end
-        end
-
-        object
-      end # variable
-
-      def lookup_and_evaluate(obj, key)
-        if (value = obj[key]).is_a?(Proc) && obj.respond_to?(:[]=)
         obj[key] = (value.arity == 0) ? value.call : value.call(self)
       else
         value
       end
-      end # lookup_and_evaluate
+    end
+
+    private
+
+    def internal_error
+      # raise and catch to set backtrace and cause on exception
+      raise Liquid::InternalError, 'internal'
+    rescue Liquid::InternalError => exc
+      exc
+    end
 
     def squash_instance_assigns_with_environments
-        @scopes.last.each_key do |k|
+      @scope.each_key do |k|
         @environments.each do |env|
-            if env.has_key?(k)
+          if env.key?(k)
-              scopes.last[k] = lookup_and_evaluate(env, k)
+            @scope[k] = [lookup_and_evaluate(env, k)]
             break
           end
         end
       end
     end # squash_instance_assigns_with_environments
   end # Context
-
 end # Liquid

lib/liquid/document.rb

@@ -1,17 +1,27 @@
 module Liquid
-  class Document < Block
+  class Document < BlockBody
-    # we don't need markup to open this block
+    def self.parse(tokens, parse_context)
-    def initialize(tokens)
+      doc = new
-      parse(tokens)
+      doc.parse(tokens, parse_context)
+      doc
     end
 
-    # There isn't a real delimter
+    def parse(tokens, parse_context)
-    def block_delimiter
+      super do |end_tag_name, end_tag_params|
-      []
+        unknown_tag(end_tag_name, parse_context) if end_tag_name
+      end
+    rescue SyntaxError => e
+      e.line_number ||= parse_context.line_number
+      raise
     end
 
-    # Document blocks don't need to be terminated since they are not actually opened
+    def unknown_tag(tag, parse_context)
-    def assert_missing_delimitation!
+      case tag
+      when 'else'.freeze, 'end'.freeze
+        raise SyntaxError.new(parse_context.locale.t("errors.syntax.unexpected_outer_tag".freeze, tag: tag))
+      else
+        raise SyntaxError.new(parse_context.locale.t("errors.syntax.unknown_tag".freeze, tag: tag))
+      end
     end
   end
 end

lib/liquid/drop.rb

@@ -1,10 +1,11 @@
-module Liquid
+require 'set'
 
-  # A drop in liquid is a class which allows you to to export DOM like things to liquid
+module Liquid
+  # A drop in liquid is a class which allows you to export DOM like things to liquid.
   # Methods of drops are callable.
-  # The main use for liquid drops is the implement lazy loaded objects.
+  # The main use for liquid drops is to implement lazy loaded objects.
   # If you would like to make data available to the web designers which you don't want loaded unless needed then
-  # a drop is a great way to do that
+  # a drop is a great way to do that.
   #
   # Example:
   #
@@ -17,35 +18,61 @@ module Liquid
   #   tmpl = Liquid::Template.parse( ' {% for product in product.top_sales %} {{ product.name }} {%endfor%} '  )
   #   tmpl.render('product' => ProductDrop.new ) # will invoke top_sales query.
   #
-  # Your drop can either implement the methods sans any parameters or implement the before_method(name) method which is a
+  # Your drop can either implement the methods sans any parameters
-  # catch all
+  # or implement the liquid_method_missing(name) method which is a catch all.
   class Drop
     attr_writer :context
 
     # Catch all for the method
-    def before_method(method)
+    def liquid_method_missing(method)
-      nil
+      return nil unless @context && @context.strict_variables
+      raise Liquid::UndefinedDropMethod, "undefined method #{method}"
     end
 
     # called by liquid to invoke a drop
-    def invoke_drop(method)
+    def invoke_drop(method_or_key)
-      # for backward compatibility with Ruby 1.8
+      if self.class.invokable?(method_or_key)
-      methods = self.class.public_instance_methods.map { |m| m.to_s }
+        send(method_or_key)
-      if methods.include?(method.to_s)
-        send(method.to_sym)
       else
-        before_method(method)
+        liquid_method_missing(method_or_key)
       end
     end
 
-    def has_key?(name)
+    def key?(_name)
       true
     end
 
+    def inspect
+      self.class.to_s
+    end
+
     def to_liquid
       self
     end
 
-    alias :[] :invoke_drop
+    def to_s
+      self.class.name
+    end
+
+    alias_method :[], :invoke_drop
+
+    # Check for method existence without invoking respond_to?, which creates symbols
+    def self.invokable?(method_name)
+      invokable_methods.include?(method_name.to_s)
+    end
+
+    def self.invokable_methods
+      @invokable_methods ||= begin
+        blacklist = Liquid::Drop.public_instance_methods + [:each]
+
+        if include?(Enumerable)
+          blacklist += Enumerable.public_instance_methods
+          blacklist -= [:sort, :count, :first, :min, :max, :include?]
+        end
+
+        whitelist = [:to_liquid] + (public_instance_methods - blacklist)
+        Set.new(whitelist.map(&:to_s))
+      end
+    end
   end
 end

lib/liquid/errors.rb

@@ -1,11 +1,56 @@
 module Liquid
-  class Error < ::StandardError; end
+  class Error < ::StandardError
+    attr_accessor :line_number
+    attr_accessor :template_name
+    attr_accessor :markup_context
 
-  class ArgumentError < Error; end
+    def to_s(with_prefix = true)
-  class ContextError < Error; end
+      str = ""
-  class FilterNotFound < Error; end
+      str << message_prefix if with_prefix
-  class FileSystemError < Error; end
+      str << super()
-  class StandardError < Error; end
+
-  class SyntaxError < Error; end
+      if markup_context
-  class StackLevelError < Error; end
+        str << " "
+        str << markup_context
+      end
+
+      str
+    end
+
+    private
+
+    def message_prefix
+      str = ""
+      if is_a?(SyntaxError)
+        str << "Liquid syntax error"
+      else
+        str << "Liquid error"
+      end
+
+      if line_number
+        str << " ("
+        str << template_name << " " if template_name
+        str << "line " << line_number.to_s << ")"
+      end
+
+      str << ": "
+      str
+    end
+  end
+
+  ArgumentError = Class.new(Error)
+  ContextError = Class.new(Error)
+  FileSystemError = Class.new(Error)
+  StandardError = Class.new(Error)
+  SyntaxError = Class.new(Error)
+  StackLevelError = Class.new(Error)
+  TaintedError = Class.new(Error)
+  MemoryError = Class.new(Error)
+  ZeroDivisionError = Class.new(Error)
+  FloatDomainError = Class.new(Error)
+  UndefinedVariable = Class.new(Error)
+  UndefinedDropMethod = Class.new(Error)
+  UndefinedFilter = Class.new(Error)
+  MethodOverrideError = Class.new(Error)
+  InternalError = Class.new(Error)
 end

lib/liquid/expression.rb

@@ -0,0 +1,49 @@
+module Liquid
+  class Expression
+    class MethodLiteral
+      attr_reader :method_name, :to_s
+
+      def initialize(method_name, to_s)
+        @method_name = method_name
+        @to_s = to_s
+      end
+
+      def to_liquid
+        to_s
+      end
+    end
+
+    LITERALS = {
+      nil => nil, 'nil'.freeze => nil, 'null'.freeze => nil, ''.freeze => nil,
+      'true'.freeze  => true,
+      'false'.freeze => false,
+      'blank'.freeze => MethodLiteral.new(:blank?, '').freeze,
+      'empty'.freeze => MethodLiteral.new(:empty?, '').freeze
+    }.freeze
+
+    SINGLE_QUOTED_STRING = /\A'(.*)'\z/m
+    DOUBLE_QUOTED_STRING = /\A"(.*)"\z/m
+    INTEGERS_REGEX       = /\A(-?\d+)\z/
+    FLOATS_REGEX         = /\A(-?\d[\d\.]+)\z/
+    RANGES_REGEX         = /\A\((\S+)\.\.(\S+)\)\z/
+
+    def self.parse(markup)
+      if LITERALS.key?(markup)
+        LITERALS[markup]
+      else
+        case markup
+        when SINGLE_QUOTED_STRING, DOUBLE_QUOTED_STRING
+          $1
+        when INTEGERS_REGEX
+          $1.to_i
+        when RANGES_REGEX
+          RangeLookup.parse($1, $2)
+        when FLOATS_REGEX
+          $1.to_f
+        else
+          VariableLookup.parse(markup)
+        end
+      end
+    end
+  end
+end

lib/liquid/extensions.rb

@@ -7,6 +7,12 @@ class String # :nodoc:
   end
 end
 
+class Symbol # :nodoc:
+  def to_liquid
+    to_s
+  end
+end
+
 class Array # :nodoc:
   def to_liquid
     self
@@ -25,6 +31,12 @@ class Numeric  # :nodoc:
   end
 end
 
+class Range # :nodoc:
+  def to_liquid
+    self
+  end
+end
+
 class Time # :nodoc:
   def to_liquid
     self
@@ -43,14 +55,20 @@ class Date  # :nodoc:
   end
 end
 
-def true.to_liquid  # :nodoc:
+class TrueClass
+  def to_liquid # :nodoc:
     self
   end
+end
 
-def false.to_liquid # :nodoc:
+class FalseClass
+  def to_liquid # :nodoc:
     self
   end
+end
 
-def nil.to_liquid # :nodoc:
+class NilClass
+  def to_liquid # :nodoc:
     self
   end
+end

lib/liquid/file_system.rb

@@ -1,5 +1,5 @@
 module Liquid
-  # A Liquid file system is way to let your templates retrieve other templates for use with the include tag.
+  # A Liquid file system is a way to let your templates retrieve other templates for use with the include tag.
   #
   # You can implement subclasses that retrieve templates from the database, from the file system using a different
   # path structure, you can provide them as hard-coded inline strings, or any manner that you see fit.
@@ -14,7 +14,7 @@ module Liquid
   # This will parse the template with a LocalFileSystem implementation rooted at 'template_path'.
   class BlankFileSystem
     # Called by Liquid to retrieve a template file
-    def read_template_file(template_path)
+    def read_template_file(_template_path)
       raise FileSystemError, "This liquid context does not allow includes."
     end
   end
@@ -31,30 +31,41 @@ module Liquid
   #   file_system.full_path("mypartial")       # => "/some/path/_mypartial.liquid"
   #   file_system.full_path("dir/mypartial")   # => "/some/path/dir/_mypartial.liquid"
   #
+  # Optionally in the second argument you can specify a custom pattern for template filenames.
+  # The Kernel::sprintf format specification is used.
+  # Default pattern is "_%s.liquid".
+  #
+  # Example:
+  #
+  #   file_system = Liquid::LocalFileSystem.new("/some/path", "%s.html")
+  #
+  #   file_system.full_path("index") # => "/some/path/index.html"
+  #
   class LocalFileSystem
     attr_accessor :root
 
-    def initialize(root)
+    def initialize(root, pattern = "_%s.liquid".freeze)
       @root = root
+      @pattern = pattern
     end
 
     def read_template_file(template_path)
       full_path = full_path(template_path)
-      raise FileSystemError, "No such template '#{template_path}'" unless File.exists?(full_path)
+      raise FileSystemError, "No such template '#{template_path}'" unless File.exist?(full_path)
 
       File.read(full_path)
     end
 
     def full_path(template_path)
-      raise FileSystemError, "Illegal template name '#{template_path}'" unless template_path =~ /^[^.\/][a-zA-Z0-9_\/]+$/
+      raise FileSystemError, "Illegal template name '#{template_path}'" unless template_path =~ /\A[^.\/][a-zA-Z0-9_\/]+\z/
 
-      full_path = if template_path.include?('/')
+      full_path = if template_path.include?('/'.freeze)
-        File.join(root, File.dirname(template_path), "_#{File.basename(template_path)}.liquid")
+        File.join(root, File.dirname(template_path), @pattern % File.basename(template_path))
       else
-        File.join(root, "_#{template_path}.liquid")
+        File.join(root, @pattern % template_path)
       end
 
-      raise FileSystemError, "Illegal template path '#{File.expand_path(full_path)}'" unless File.expand_path(full_path) =~ /^#{File.expand_path(root)}/
+      raise FileSystemError, "Illegal template path '#{File.expand_path(full_path)}'" unless File.expand_path(full_path).start_with?(File.expand_path(root))
 
       full_path
     end

lib/liquid/forloop_drop.rb

@@ -0,0 +1,42 @@
+module Liquid
+  class ForloopDrop < Drop
+    def initialize(name, length, parentloop)
+      @name = name
+      @length = length
+      @parentloop = parentloop
+      @index = 0
+    end
+
+    attr_reader :name, :length, :parentloop
+
+    def index
+      @index + 1
+    end
+
+    def index0
+      @index
+    end
+
+    def rindex
+      @length - @index
+    end
+
+    def rindex0
+      @length - @index - 1
+    end
+
+    def first
+      @index == 0
+    end
+
+    def last
+      @index == @length - 1
+    end
+
+    protected
+
+    def increment!
+      @index += 1
+    end
+  end
+end

lib/liquid/htmltags.rb

@@ -1,74 +0,0 @@
-module Liquid
-  class TableRow < Block
-    Syntax = /(\w+)\s+in\s+(#{VariableSignature}+)/
-
-    def initialize(tag_name, markup, tokens)
-      if markup =~ Syntax
-        @variable_name = $1
-        @collection_name = $2
-        @attributes = {}
-        markup.scan(TagAttributes) do |key, value|
-          @attributes[key] = value
-        end
-      else
-        raise SyntaxError.new("Syntax Error in 'table_row loop' - Valid syntax: table_row [item] in [collection] cols=3")
-      end
-
-      super
-    end
-
-    def render(context)
-      collection = context[@collection_name] or return ''
-
-      if @attributes['limit'] or @attributes['offset']
-        limit = context[@attributes['limit']] || -1
-        offset = context[@attributes['offset']] || 0
-        collection = collection[offset.to_i..(limit.to_i + offset.to_i - 1)]
-      end
-
-      length = collection.length
-
-      cols = context[@attributes['cols']].to_i
-
-      row = 1
-      col = 0
-
-      result = ["<tr class=\"row1\">\n"]
-      context.stack do
-
-        collection.each_with_index do |item, index|
-          context[@variable_name] = item
-          context['tablerowloop'] = {
-            'length'  => length,
-            'index'   => index + 1,
-            'index0'  => index,
-            'col'     => col + 1,
-            'col0'    => col,
-            'index0'  => index,
-            'rindex'  => length - index,
-            'rindex0' => length - index -1,
-            'first'   => (index == 0),
-            'last'    => (index == length - 1),
-            'col_first' => (col == 0),
-            'col_last'  => (col == cols - 1)
-          }
-
-
-          col += 1
-
-          result << ["<td class=\"col#{col}\">"] + render_all(@nodelist, context) + ['</td>']
-
-          if col == cols and not (index == length - 1)
-            col  = 0
-            row += 1
-            result << ["</tr>\n<tr class=\"row#{row}\">"]
-          end
-
-        end
-      end
-      result + ["</tr>\n"]
-    end
-  end
-
-  Template.register_tag('tablerow', TableRow)
-end

lib/liquid/i18n.rb

@@ -0,0 +1,39 @@
+require 'yaml'
+
+module Liquid
+  class I18n
+    DEFAULT_LOCALE = File.join(File.expand_path(__dir__), "locales", "en.yml")
+
+    TranslationError = Class.new(StandardError)
+
+    attr_reader :path
+
+    def initialize(path = DEFAULT_LOCALE)
+      @path = path
+    end
+
+    def translate(name, vars = {})
+      interpolate(deep_fetch_translation(name), vars)
+    end
+    alias_method :t, :translate
+
+    def locale
+      @locale ||= YAML.load_file(@path)
+    end
+
+    private
+
+    def interpolate(name, vars)
+      name.gsub(/%\{(\w+)\}/) do
+        # raise TranslationError, "Undefined key #{$1} for interpolation in translation #{name}"  unless vars[$1.to_sym]
+        (vars[$1.to_sym]).to_s
+      end
+    end
+
+    def deep_fetch_translation(name)
+      name.split('.'.freeze).reduce(locale) do |level, cur|
+        level[cur] or raise TranslationError, "Translation for #{name} does not exist in locale #{path}"
+      end
+    end
+  end
+end

lib/liquid/interrupts.rb

@@ -0,0 +1,16 @@
+module Liquid
+  # An interrupt is any command that breaks processing of a block (ex: a for loop).
+  class Interrupt
+    attr_reader :message
+
+    def initialize(message = nil)
+      @message = message || "interrupt".freeze
+    end
+  end
+
+  # Interrupt that is thrown whenever a {% break %} is called.
+  class BreakInterrupt < Interrupt; end
+
+  # Interrupt that is thrown whenever a {% continue %} is called.
+  class ContinueInterrupt < Interrupt; end
+end

lib/liquid/lexer.rb

@@ -0,0 +1,55 @@
+require "strscan"
+module Liquid
+  class Lexer
+    SPECIALS = {
+      '|'.freeze => :pipe,
+      '.'.freeze => :dot,
+      ':'.freeze => :colon,
+      ','.freeze => :comma,
+      '['.freeze => :open_square,
+      ']'.freeze => :close_square,
+      '('.freeze => :open_round,
+      ')'.freeze => :close_round,
+      '?'.freeze => :question,
+      '-'.freeze => :dash
+    }.freeze
+    IDENTIFIER = /[a-zA-Z_][\w-]*\??/
+    SINGLE_STRING_LITERAL = /'[^\']*'/
+    DOUBLE_STRING_LITERAL = /"[^\"]*"/
+    NUMBER_LITERAL = /-?\d+(\.\d+)?/
+    DOTDOT = /\.\./
+    COMPARISON_OPERATOR = /==|!=|<>|<=?|>=?|contains(?=\s)/
+    WHITESPACE_OR_NOTHING = /\s*/
+
+    def initialize(input)
+      @ss = StringScanner.new(input)
+    end
+
+    def tokenize
+      @output = []
+
+      until @ss.eos?
+        @ss.skip(WHITESPACE_OR_NOTHING)
+        break if @ss.eos?
+        tok = case
+        when t = @ss.scan(COMPARISON_OPERATOR) then [:comparison, t]
+        when t = @ss.scan(SINGLE_STRING_LITERAL) then [:string, t]
+        when t = @ss.scan(DOUBLE_STRING_LITERAL) then [:string, t]
+        when t = @ss.scan(NUMBER_LITERAL) then [:number, t]
+        when t = @ss.scan(IDENTIFIER) then [:id, t]
+        when t = @ss.scan(DOTDOT) then [:dotdot, t]
+        else
+          c = @ss.getch
+          if s = SPECIALS[c]
+            [s, c]
+          else
+            raise SyntaxError, "Unexpected character #{c}"
+          end
+        end
+        @output << tok
+      end
+
+      @output << [:end_of_string]
+    end
+  end
+end

lib/liquid/locales/en.yml

@@ -0,0 +1,26 @@
+---
+  errors:
+    syntax:
+      tag_unexpected_args: "Syntax Error in '%{tag}' - Valid syntax: %{tag}"
+      assign: "Syntax Error in 'assign' - Valid syntax: assign [var] = [source]"
+      capture: "Syntax Error in 'capture' - Valid syntax: capture [var]"
+      case: "Syntax Error in 'case' - Valid syntax: case [condition]"
+      case_invalid_when: "Syntax Error in tag 'case' - Valid when condition: {% when [condition] [or condition2...] %}"
+      case_invalid_else: "Syntax Error in tag 'case' - Valid else condition: {% else %} (no parameters) "
+      cycle: "Syntax Error in 'cycle' - Valid syntax: cycle [name :] var [, var2, var3 ...]"
+      for: "Syntax Error in 'for loop' - Valid syntax: for [item] in [collection]"
+      for_invalid_in: "For loops require an 'in' clause"
+      for_invalid_attribute: "Invalid attribute in for loop. Valid attributes are limit and offset"
+      if: "Syntax Error in tag 'if' - Valid syntax: if [expression]"
+      include: "Error in tag 'include' - Valid syntax: include '[template]' (with|for) [object|collection]"
+      unknown_tag: "Unknown tag '%{tag}'"
+      invalid_delimiter: "'%{tag}' is not a valid delimiter for %{block_name} tags. use %{block_delimiter}"
+      unexpected_else: "%{block_name} tag does not expect 'else' tag"
+      unexpected_outer_tag: "Unexpected outer '%{tag}' tag"
+      tag_termination: "Tag '%{token}' was not properly terminated with regexp: %{tag_end}"
+      variable_termination: "Variable '%{token}' was not properly terminated with regexp: %{tag_end}"
+      tag_never_closed: "'%{block_name}' tag was never closed"
+      meta_syntax_error: "Liquid syntax error: #{e.message}"
+      table_row: "Syntax Error in 'table_row loop' - Valid syntax: table_row [item] in [collection] cols=3"
+    argument:
+      include: "Argument error in tag 'include' - Illegal template name"

lib/liquid/module_ex.rb

@@ -1,62 +0,0 @@
-# Copyright 2007 by Domizio Demichelis
-# This library is free software. It may be used, redistributed and/or modified
-# under the same terms as Ruby itself
-#
-# This extension is usesd in order to expose the object of the implementing class
-# to liquid as it were a Drop. It also limits the liquid-callable methods of the instance
-# to the allowed method passed with the liquid_methods call
-# Example:
-#
-# class SomeClass
-#   liquid_methods :an_allowed_method
-#
-#   def an_allowed_method
-#     'this comes from an allowed method'
-#   end
-#   def unallowed_method
-#     'this will never be an output'
-#   end
-# end
-#
-# if you want to extend the drop to other methods you can defines more methods
-# in the class <YourClass>::LiquidDropClass
-#
-#   class SomeClass::LiquidDropClass
-#     def another_allowed_method
-#       'and this from another allowed method'
-#     end
-#   end
-# end
-#
-# usage:
-# @something = SomeClass.new
-#
-# template:
-# {{something.an_allowed_method}}{{something.unallowed_method}} {{something.another_allowed_method}}
-#
-# output:
-# 'this comes from an allowed method and this from another allowed method'
-#
-# You can also chain associations, by adding the liquid_method call in the
-# association models.
-#
-class Module
-
-  def liquid_methods(*allowed_methods)
-    drop_class = eval "class #{self.to_s}::LiquidDropClass < Liquid::Drop; self; end"
-    define_method :to_liquid do
-      drop_class.new(self)
-    end
-    drop_class.class_eval do
-      def initialize(object)
-        @object = object
-      end
-      allowed_methods.each do |sym|
-        define_method sym do
-          @object.send sym
-        end
-      end
-    end
-  end
-
-end

lib/liquid/parse_context.rb

@@ -0,0 +1,38 @@
+module Liquid
+  class ParseContext
+    attr_accessor :locale, :line_number, :trim_whitespace, :depth
+    attr_reader :partial, :warnings, :error_mode
+
+    def initialize(options = {})
+      @template_options = options ? options.dup : {}
+      @locale = @template_options[:locale] ||= I18n.new
+      @warnings = []
+      self.depth = 0
+      self.partial = false
+    end
+
+    def [](option_key)
+      @options[option_key]
+    end
+
+    def partial=(value)
+      @partial = value
+      @options = value ? partial_options : @template_options
+      @error_mode = @options[:error_mode] || Template.error_mode
+      value
+    end
+
+    def partial_options
+      @partial_options ||= begin
+        dont_pass = @template_options[:include_options_blacklist]
+        if dont_pass == true
+          { locale: locale }
+        elsif dont_pass.is_a?(Array)
+          @template_options.reject { |k, v| dont_pass.include?(k) }
+        else
+          @template_options
+        end
+      end
+    end
+  end
+end

lib/liquid/parse_tree_visitor.rb

@@ -0,0 +1,42 @@
+# frozen_string_literal: true
+
+module Liquid
+  class ParseTreeVisitor
+    def self.for(node, callbacks = Hash.new(proc {}))
+      if defined?(node.class::ParseTreeVisitor)
+        node.class::ParseTreeVisitor
+      else
+        self
+      end.new(node, callbacks)
+    end
+
+    def initialize(node, callbacks)
+      @node = node
+      @callbacks = callbacks
+    end
+
+    def add_callback_for(*classes, &block)
+      callback = block
+      callback = ->(node, _) { yield node } if block.arity.abs == 1
+      callback = ->(_, _) { yield } if block.arity.zero?
+      classes.each { |klass| @callbacks[klass] = callback }
+      self
+    end
+
+    def visit(context = nil)
+      children.map do |node|
+        item, new_context = @callbacks[node.class].call(node, context)
+        [
+          item,
+          ParseTreeVisitor.for(node, @callbacks).visit(new_context || context)
+        ]
+      end
+    end
+
+    protected
+
+    def children
+      @node.respond_to?(:nodelist) ? Array(@node.nodelist) : []
+    end
+  end
+end

lib/liquid/parser.rb

@@ -0,0 +1,90 @@
+module Liquid
+  class Parser
+    def initialize(input)
+      l = Lexer.new(input)
+      @tokens = l.tokenize
+      @p = 0 # pointer to current location
+    end
+
+    def jump(point)
+      @p = point
+    end
+
+    def consume(type = nil)
+      token = @tokens[@p]
+      if type && token[0] != type
+        raise SyntaxError, "Expected #{type} but found #{@tokens[@p].first}"
+      end
+      @p += 1
+      token[1]
+    end
+
+    # Only consumes the token if it matches the type
+    # Returns the token's contents if it was consumed
+    # or false otherwise.
+    def consume?(type)
+      token = @tokens[@p]
+      return false unless token && token[0] == type
+      @p += 1
+      token[1]
+    end
+
+    # Like consume? Except for an :id token of a certain name
+    def id?(str)
+      token = @tokens[@p]
+      return false unless token && token[0] == :id
+      return false unless token[1] == str
+      @p += 1
+      token[1]
+    end
+
+    def look(type, ahead = 0)
+      tok = @tokens[@p + ahead]
+      return false unless tok
+      tok[0] == type
+    end
+
+    def expression
+      token = @tokens[@p]
+      if token[0] == :id
+        variable_signature
+      elsif [:string, :number].include? token[0]
+        consume
+      elsif token.first == :open_round
+        consume
+        first = expression
+        consume(:dotdot)
+        last = expression
+        consume(:close_round)
+        "(#{first}..#{last})"
+      else
+        raise SyntaxError, "#{token} is not a valid expression"
+      end
+    end
+
+    def argument
+      str = ""
+      # might be a keyword argument (identifier: expression)
+      if look(:id) && look(:colon, 1)
+        str << consume << consume << ' '.freeze
+      end
+
+      str << expression
+      str
+    end
+
+    def variable_signature
+      str = consume(:id)
+      while look(:open_square)
+        str << consume
+        str << expression
+        str << consume(:close_square)
+      end
+      if look(:dot)
+        str << consume
+        str << variable_signature
+      end
+      str
+    end
+  end
+end

lib/liquid/parser_switching.rb

@@ -0,0 +1,31 @@
+module Liquid
+  module ParserSwitching
+    def parse_with_selected_parser(markup)
+      case parse_context.error_mode
+      when :strict then strict_parse_with_error_context(markup)
+      when :lax    then lax_parse(markup)
+      when :warn
+        begin
+          return strict_parse_with_error_context(markup)
+        rescue SyntaxError => e
+          parse_context.warnings << e
+          return lax_parse(markup)
+        end
+      end
+    end
+
+    private
+
+    def strict_parse_with_error_context(markup)
+      strict_parse(markup)
+    rescue SyntaxError => e
+      e.line_number = line_number
+      e.markup_context = markup_context(markup)
+      raise e
+    end
+
+    def markup_context(markup)
+      "in \"#{markup.strip}\""
+    end
+  end
+end

lib/liquid/profiler.rb

@@ -0,0 +1,158 @@
+require 'liquid/profiler/hooks'
+
+module Liquid
+  # Profiler enables support for profiling template rendering to help track down performance issues.
+  #
+  # To enable profiling, first require 'liquid/profiler'.
+  # Then, to profile a parse/render cycle, pass the <tt>profile: true</tt> option to <tt>Liquid::Template.parse</tt>.
+  # After <tt>Liquid::Template#render</tt> is called, the template object makes available an instance of this
+  # class via the <tt>Liquid::Template#profiler</tt> method.
+  #
+  #   template = Liquid::Template.parse(template_content, profile: true)
+  #   output  = template.render
+  #   profile = template.profiler
+  #
+  # This object contains all profiling information, containing information on what tags were rendered,
+  # where in the templates these tags live, and how long each tag took to render.
+  #
+  # This is a tree structure that is Enumerable all the way down, and keeps track of tags and rendering times
+  # inside of <tt>{% include %}</tt> tags.
+  #
+  #   profile.each do |node|
+  #     # Access to the node itself
+  #     node.code
+  #
+  #     # Which template and line number of this node.
+  #     # If top level, this will be "<root>".
+  #     node.partial
+  #     node.line_number
+  #
+  #     # Render time in seconds of this node
+  #     node.render_time
+  #
+  #     # If the template used {% include %}, this node will also have children.
+  #     node.children.each do |child2|
+  #       # ...
+  #     end
+  #   end
+  #
+  # Profiler also exposes the total time of the template's render in <tt>Liquid::Profiler#total_render_time</tt>.
+  #
+  # All render times are in seconds. There is a small performance hit when profiling is enabled.
+  #
+  class Profiler
+    include Enumerable
+
+    class Timing
+      attr_reader :code, :partial, :line_number, :children
+
+      def initialize(node, partial)
+        @code        = node.respond_to?(:raw) ? node.raw : node
+        @partial     = partial
+        @line_number = node.respond_to?(:line_number) ? node.line_number : nil
+        @children    = []
+      end
+
+      def self.start(node, partial)
+        new(node, partial).tap(&:start)
+      end
+
+      def start
+        @start_time = Time.now
+      end
+
+      def finish
+        @end_time = Time.now
+      end
+
+      def render_time
+        @end_time - @start_time
+      end
+    end
+
+    def self.profile_node_render(node)
+      if Profiler.current_profile && node.respond_to?(:render)
+        Profiler.current_profile.start_node(node)
+        output = yield
+        Profiler.current_profile.end_node(node)
+        output
+      else
+        yield
+      end
+    end
+
+    def self.profile_children(template_name)
+      if Profiler.current_profile
+        Profiler.current_profile.push_partial(template_name)
+        output = yield
+        Profiler.current_profile.pop_partial
+        output
+      else
+        yield
+      end
+    end
+
+    def self.current_profile
+      Thread.current[:liquid_profiler]
+    end
+
+    def initialize
+      @partial_stack = ["<root>"]
+
+      @root_timing = Timing.new("", current_partial)
+      @timing_stack = [@root_timing]
+
+      @render_start_at = Time.now
+      @render_end_at = @render_start_at
+    end
+
+    def start
+      Thread.current[:liquid_profiler] = self
+      @render_start_at = Time.now
+    end
+
+    def stop
+      Thread.current[:liquid_profiler] = nil
+      @render_end_at = Time.now
+    end
+
+    def total_render_time
+      @render_end_at - @render_start_at
+    end
+
+    def each(&block)
+      @root_timing.children.each(&block)
+    end
+
+    def [](idx)
+      @root_timing.children[idx]
+    end
+
+    def length
+      @root_timing.children.length
+    end
+
+    def start_node(node)
+      @timing_stack.push(Timing.start(node, current_partial))
+    end
+
+    def end_node(_node)
+      timing = @timing_stack.pop
+      timing.finish
+
+      @timing_stack.last.children << timing
+    end
+
+    def current_partial
+      @partial_stack.last
+    end
+
+    def push_partial(partial_name)
+      @partial_stack.push(partial_name)
+    end
+
+    def pop_partial
+      @partial_stack.pop
+    end
+  end
+end

lib/liquid/profiler/hooks.rb

@@ -0,0 +1,23 @@
+module Liquid
+  class BlockBody
+    def render_node_with_profiling(node, output, context, skip_output = false)
+      Profiler.profile_node_render(node) do
+        render_node_without_profiling(node, output, context, skip_output)
+      end
+    end
+
+    alias_method :render_node_without_profiling, :render_node_to_output
+    alias_method :render_node_to_output, :render_node_with_profiling
+  end
+
+  class Include < Tag
+    def render_with_profiling(context)
+      Profiler.profile_children(context.evaluate(@template_name_expr).to_s) do
+        render_without_profiling(context)
+      end
+    end
+
+    alias_method :render_without_profiling, :render
+    alias_method :render, :render_with_profiling
+  end
+end

lib/liquid/range_lookup.rb

@@ -0,0 +1,37 @@
+module Liquid
+  class RangeLookup
+    def self.parse(start_markup, end_markup)
+      start_obj = Expression.parse(start_markup)
+      end_obj = Expression.parse(end_markup)
+      if start_obj.respond_to?(:evaluate) || end_obj.respond_to?(:evaluate)
+        new(start_obj, end_obj)
+      else
+        start_obj.to_i..end_obj.to_i
+      end
+    end
+
+    def initialize(start_obj, end_obj)
+      @start_obj = start_obj
+      @end_obj = end_obj
+    end
+
+    def evaluate(context)
+      start_int = to_integer(context.evaluate(@start_obj))
+      end_int = to_integer(context.evaluate(@end_obj))
+      start_int..end_int
+    end
+
+    private
+
+    def to_integer(input)
+      case input
+      when Integer
+        input
+      when NilClass, String
+        input.to_i
+      else
+        Utils.to_integer(input)
+      end
+    end
+  end
+end

lib/liquid/resource_limits.rb

@@ -0,0 +1,23 @@
+module Liquid
+  class ResourceLimits
+    attr_accessor :render_length, :render_score, :assign_score,
+      :render_length_limit, :render_score_limit, :assign_score_limit
+
+    def initialize(limits)
+      @render_length_limit = limits[:render_length_limit]
+      @render_score_limit = limits[:render_score_limit]
+      @assign_score_limit = limits[:assign_score_limit]
+      reset
+    end
+
+    def reached?
+      (@render_length_limit && @render_length > @render_length_limit) ||
+        (@render_score_limit && @render_score > @render_score_limit) ||
+        (@assign_score_limit && @assign_score > @assign_score_limit)
+    end
+
+    def reset
+      @render_length = @render_score = @assign_score = 0
+    end
+  end
+end

lib/liquid/standardfilters.rb

@@ -1,21 +1,34 @@
 require 'cgi'
+require 'bigdecimal'
 
 module Liquid
-
   module StandardFilters
+    HTML_ESCAPE = {
+      '&'.freeze => '&'.freeze,
+      '>'.freeze => '>'.freeze,
+      '<'.freeze => '&lt;'.freeze,
+      '"'.freeze => '&quot;'.freeze,
+      "'".freeze => '&#39;'.freeze
+    }.freeze
+    HTML_ESCAPE_ONCE_REGEXP = /["><']|&(?!([a-zA-Z]+|(#\d+));)/
+    STRIP_HTML_BLOCKS = Regexp.union(
+      /<script.*?<\/script>/m,
+      /<!--.*?-->/m,
+      /<style.*?<\/style>/m
+    )
+    STRIP_HTML_TAGS = /<.*?>/m
 
     # Return the size of an array or of an string
     def size(input)
-
       input.respond_to?(:size) ? input.size : 0
     end
 
-    # convert a input string to DOWNCASE
+    # convert an input string to DOWNCASE
     def downcase(input)
       input.to_s.downcase
     end
 
-    # convert a input string to UPCASE
+    # convert an input string to UPCASE
     def upcase(input)
       input.to_s.upcase
     end
@@ -26,87 +39,234 @@ module Liquid
     end
 
     def escape(input)
-      CGI.escapeHTML(input) rescue input
+      CGI.escapeHTML(input.to_s).untaint unless input.nil?
     end
-
-    def escape_once(input)
-      ActionView::Helpers::TagHelper.escape_once(input) rescue input
-    end
-
     alias_method :h, :escape
 
-    # Truncate a string down to x characters
+    def escape_once(input)
-    def truncate(input, length = 50, truncate_string = "...")
+      input.to_s.gsub(HTML_ESCAPE_ONCE_REGEXP, HTML_ESCAPE)
-      if input.nil? then return end
-      l = length.to_i - truncate_string.length
-      l = 0 if l < 0
-      input.length > length.to_i ? input[0...l] + truncate_string : input
     end
 
-    def truncatewords(input, words = 15, truncate_string = "...")
+    def url_encode(input)
-      if input.nil? then return end
+      CGI.escape(input.to_s) unless input.nil?
-      wordlist = input.to_s.split
+    end
-      l = words.to_i - 1
+
+    def url_decode(input)
+      return if input.nil?
+
+      result = CGI.unescape(input.to_s)
+      raise Liquid::ArgumentError, "invalid byte sequence in #{result.encoding}" unless result.valid_encoding?
+
+      result
+    end
+
+    def slice(input, offset, length = nil)
+      offset = Utils.to_integer(offset)
+      length = length ? Utils.to_integer(length) : 1
+
+      if input.is_a?(Array)
+        input.slice(offset, length) || []
+      else
+        input.to_s.slice(offset, length) || ''
+      end
+    end
+
+    # Truncate a string down to x characters
+    def truncate(input, length = 50, truncate_string = "...".freeze)
+      return if input.nil?
+      input_str = input.to_s
+      length = Utils.to_integer(length)
+      truncate_string_str = truncate_string.to_s
+      l = length - truncate_string_str.length
       l = 0 if l < 0
-      wordlist.length > l ? wordlist[0..l].join(" ") + truncate_string : input
+      input_str.length > length ? input_str[0...l] + truncate_string_str : input_str
+    end
+
+    def truncatewords(input, words = 15, truncate_string = "...".freeze)
+      return if input.nil?
+      wordlist = input.to_s.split
+      words = Utils.to_integer(words)
+      l = words - 1
+      l = 0 if l < 0
+      wordlist.length > l ? wordlist[0..l].join(" ".freeze) + truncate_string.to_s : input
+    end
+
+    # Split input string into an array of substrings separated by given pattern.
+    #
+    # Example:
+    #   <div class="summary">{{ post | split '//' | first }}</div>
+    #
+    def split(input, pattern)
+      input.to_s.split(pattern.to_s)
+    end
+
+    def strip(input)
+      input.to_s.strip
+    end
+
+    def lstrip(input)
+      input.to_s.lstrip
+    end
+
+    def rstrip(input)
+      input.to_s.rstrip
     end
 
     def strip_html(input)
-      input.to_s.gsub(/<script.*?<\/script>/, '').gsub(/<.*?>/, '')
+      empty = ''.freeze
+      result = input.to_s.gsub(STRIP_HTML_BLOCKS, empty)
+      result.gsub!(STRIP_HTML_TAGS, empty)
+      result
     end
 
     # Remove all newlines from the string
     def strip_newlines(input)
-      input.to_s.gsub(/\n/, '')
+      input.to_s.gsub(/\r?\n/, ''.freeze)
     end
 
-
     # Join elements of the array with certain character between them
-    def join(input, glue = ' ')
+    def join(input, glue = ' '.freeze)
-      [input].flatten.join(glue)
+      InputIterator.new(input).join(glue)
     end
 
     # Sort elements of the array
     # provide optional property with which to sort an array of hashes or drops
     def sort(input, property = nil)
-      ary = [input].flatten
+      ary = InputIterator.new(input)
+
+      return [] if ary.empty?
+
       if property.nil?
-        ary.sort
+        ary.sort do |a, b|
-      elsif ary.first.respond_to?('[]') and !ary.first[property].nil?
+          nil_safe_compare(a, b)
-        ary.sort {|a,b| a[property] <=> b[property] }
-      elsif ary.first.respond_to?(property)
-        ary.sort {|a,b| a.send(property) <=> b.send(property) }
         end
+      elsif ary.all? { |el| el.respond_to?(:[]) }
+        begin
+          ary.sort { |a, b| nil_safe_compare(a[property], b[property]) }
+        rescue TypeError
+          raise_property_error(property)
+        end
+      end
+    end
+
+    # Sort elements of an array ignoring case if strings
+    # provide optional property with which to sort an array of hashes or drops
+    def sort_natural(input, property = nil)
+      ary = InputIterator.new(input)
+
+      return [] if ary.empty?
+
+      if property.nil?
+        ary.sort do |a, b|
+          nil_safe_casecmp(a, b)
+        end
+      elsif ary.all? { |el| el.respond_to?(:[]) }
+        begin
+          ary.sort { |a, b| nil_safe_casecmp(a[property], b[property]) }
+        rescue TypeError
+          raise_property_error(property)
+        end
+      end
+    end
+
+    # Filter the elements of an array to those with a certain property value.
+    # By default the target is any truthy value.
+    def where(input, property, target_value = nil)
+      ary = InputIterator.new(input)
+
+      if ary.empty?
+        []
+      elsif ary.first.respond_to?(:[]) && target_value.nil?
+        begin
+          ary.select { |item| item[property] }
+        rescue TypeError
+          raise_property_error(property)
+        end
+      elsif ary.first.respond_to?(:[])
+        begin
+          ary.select { |item| item[property] == target_value }
+        rescue TypeError
+          raise_property_error(property)
+        end
+      end
+    end
+
+    # Remove duplicate elements from an array
+    # provide optional property with which to determine uniqueness
+    def uniq(input, property = nil)
+      ary = InputIterator.new(input)
+
+      if property.nil?
+        ary.uniq
+      elsif ary.empty? # The next two cases assume a non-empty array.
+        []
+      elsif ary.first.respond_to?(:[])
+        begin
+          ary.uniq { |a| a[property] }
+        rescue TypeError
+          raise_property_error(property)
+        end
+      end
+    end
+
+    # Reverse the elements of an array
+    def reverse(input)
+      ary = InputIterator.new(input)
+      ary.reverse
     end
 
     # map/collect on a given property
     def map(input, property)
-      ary = [input].flatten
+      InputIterator.new(input).map do |e|
-      if ary.first.respond_to?('[]') and !ary.first[property].nil?
+        e = e.call if e.is_a?(Proc)
-        ary.map {|e| e[property] }
+
-      elsif ary.first.respond_to?(property)
+        if property == "to_liquid".freeze
-        ary.map {|e| e.send(property) }
+          e
+        elsif e.respond_to?(:[])
+          r = e[property]
+          r.is_a?(Proc) ? r.call : r
+        end
+      end
+    rescue TypeError
+      raise_property_error(property)
+    end
+
+    # Remove nils within an array
+    # provide optional property with which to check for nil
+    def compact(input, property = nil)
+      ary = InputIterator.new(input)
+
+      if property.nil?
+        ary.compact
+      elsif ary.empty? # The next two cases assume a non-empty array.
+        []
+      elsif ary.first.respond_to?(:[])
+        begin
+          ary.reject { |a| a[property].nil? }
+        rescue TypeError
+          raise_property_error(property)
+        end
       end
     end
 
     # Replace occurrences of a string with another
-    def replace(input, string, replacement = '')
+    def replace(input, string, replacement = ''.freeze)
-      input.to_s.gsub(string, replacement)
+      input.to_s.gsub(string.to_s, replacement.to_s)
     end
 
     # Replace the first occurrences of a string with another
-    def replace_first(input, string, replacement = '')
+    def replace_first(input, string, replacement = ''.freeze)
-      input.to_s.sub(string, replacement)
+      input.to_s.sub(string.to_s, replacement.to_s)
     end
 
     # remove a substring
     def remove(input, string)
-      input.to_s.gsub(string, '')
+      input.to_s.gsub(string.to_s, ''.freeze)
     end
 
     # remove the first occurrences of a substring
     def remove_first(input, string)
-      input.to_s.sub(string, '')
+      input.to_s.sub(string.to_s, ''.freeze)
     end
 
     # add one string to another
@@ -114,6 +274,13 @@ module Liquid
       input.to_s + string.to_s
     end
 
+    def concat(input, array)
+      unless array.respond_to?(:to_ary)
+        raise ArgumentError.new("concat filter requires an array argument")
+      end
+      InputIterator.new(input).concat(array)
+    end
+
     # prepend a string to another
     def prepend(input, string)
       string.to_s + input.to_s
@@ -121,10 +288,10 @@ module Liquid
 
     # Add <br /> tags in front of all newlines in input string
     def newline_to_br(input)
-      input.to_s.gsub(/\n/, "<br />\n")
+      input.to_s.gsub(/\n/, "<br />\n".freeze)
     end
 
-    # Reformat a date
+    # Reformat a date using Ruby's core Time#strftime( string ) -> string
     #
     #   %a - The abbreviated weekday name (``Sun'')
     #   %A - The  full  weekday  name (``Sunday'')
@@ -138,6 +305,7 @@ module Liquid
     #   %m - Month of the year (01..12)
     #   %M - Minute of the hour (00..59)
     #   %p - Meridian indicator (``AM''  or  ``PM'')
+    #   %s - Number of seconds since 1970-01-01 00:00:00 UTC.
     #   %S - Second of the minute (00..60)
     #   %U - Week  number  of the current year,
     #           starting with the first Sunday as the first
@@ -152,21 +320,14 @@ module Liquid
     #   %Y - Year with century
     #   %Z - Time zone name
     #   %% - Literal ``%'' character
+    #
+    #   See also: http://www.ruby-doc.org/core/Time.html#method-i-strftime
     def date(input, format)
+      return input if format.to_s.empty?
 
-      if format.to_s.empty?
+      return input unless date = Utils.to_date(input)
-        return input.to_s
-      end
 
-      date = input.is_a?(String) ? Time.parse(input) : input
-
-      if date.respond_to?(:strftime)
       date.strftime(format.to_s)
-      else
-        input
-      end
-    rescue => e
-      input
     end
 
     # Get the first element of the passed in array
@@ -187,39 +348,158 @@ module Liquid
       array.last if array.respond_to?(:last)
     end
 
+    # absolute value
+    def abs(input)
+      result = Utils.to_number(input).abs
+      result.is_a?(BigDecimal) ? result.to_f : result
+    end
+
     # addition
     def plus(input, operand)
-      to_number(input) + to_number(operand)
+      apply_operation(input, operand, :+)
     end
 
     # subtraction
     def minus(input, operand)
-      to_number(input) - to_number(operand)
+      apply_operation(input, operand, :-)
     end
 
     # multiplication
     def times(input, operand)
-      to_number(input) * to_number(operand)
+      apply_operation(input, operand, :*)
     end
 
     # division
     def divided_by(input, operand)
-      to_number(input) / to_number(operand)
+      apply_operation(input, operand, :/)
+    rescue ::ZeroDivisionError => e
+      raise Liquid::ZeroDivisionError, e.message
+    end
+
+    def modulo(input, operand)
+      apply_operation(input, operand, :%)
+    rescue ::ZeroDivisionError => e
+      raise Liquid::ZeroDivisionError, e.message
+    end
+
+    def round(input, n = 0)
+      result = Utils.to_number(input).round(Utils.to_number(n))
+      result = result.to_f if result.is_a?(BigDecimal)
+      result = result.to_i if n == 0
+      result
+    rescue ::FloatDomainError => e
+      raise Liquid::FloatDomainError, e.message
+    end
+
+    def ceil(input)
+      Utils.to_number(input).ceil.to_i
+    rescue ::FloatDomainError => e
+      raise Liquid::FloatDomainError, e.message
+    end
+
+    def floor(input)
+      Utils.to_number(input).floor.to_i
+    rescue ::FloatDomainError => e
+      raise Liquid::FloatDomainError, e.message
+    end
+
+    def at_least(input, n)
+      min_value = Utils.to_number(n)
+
+      result = Utils.to_number(input)
+      result = min_value if min_value > result
+      result.is_a?(BigDecimal) ? result.to_f : result
+    end
+
+    def at_most(input, n)
+      max_value = Utils.to_number(n)
+
+      result = Utils.to_number(input)
+      result = max_value if max_value < result
+      result.is_a?(BigDecimal) ? result.to_f : result
+    end
+
+    def default(input, default_value = ''.freeze)
+      if !input || input.respond_to?(:empty?) && input.empty?
+        default_value
+      else
+        input
+      end
     end
 
     private
 
-      def to_number(obj)
+    def raise_property_error(property)
-        case obj
+      raise Liquid::ArgumentError.new("cannot select the property '#{property}'")
-        when Numeric
+    end
-          obj
+
-        when String
+    def apply_operation(input, operand, operation)
-          (obj.strip =~ /^\d+\.\d+$/) ? obj.to_f : obj.to_i
+      result = Utils.to_number(input).send(operation, Utils.to_number(operand))
+      result.is_a?(BigDecimal) ? result.to_f : result
+    end
+
+    def nil_safe_compare(a, b)
+      if !a.nil? && !b.nil?
+        a <=> b
       else
-          0
+        a.nil? ? 1 : -1
       end
     end
 
+    def nil_safe_casecmp(a, b)
+      if !a.nil? && !b.nil?
+        a.to_s.casecmp(b.to_s)
+      else
+        a.nil? ? 1 : -1
+      end
+    end
+
+    class InputIterator
+      include Enumerable
+
+      def initialize(input)
+        @input = if input.is_a?(Array)
+          input.flatten
+        elsif input.is_a?(Hash)
+          [input]
+        elsif input.is_a?(Enumerable)
+          input
+        else
+          Array(input)
+        end
+      end
+
+      def join(glue)
+        to_a.join(glue.to_s)
+      end
+
+      def concat(args)
+        to_a.concat(args)
+      end
+
+      def reverse
+        reverse_each.to_a
+      end
+
+      def uniq(&block)
+        to_a.uniq(&block)
+      end
+
+      def compact
+        to_a.compact
+      end
+
+      def empty?
+        @input.each { return false }
+        true
+      end
+
+      def each
+        @input.each do |e|
+          yield(e.respond_to?(:to_liquid) ? e.to_liquid : e)
+        end
+      end
+    end
   end
 
   Template.register_filter(StandardFilters)

lib/liquid/strainer.rb

@@ -1,54 +1,66 @@
 require 'set'
 
 module Liquid
-
-  parent_object = if defined? BlankObject
-    BlankObject
-  else
-    Object
-  end
-
   # Strainer is the parent class for the filters system.
-  # New filters are mixed into the strainer class which is then instanciated for each liquid template render run.
+  # New filters are mixed into the strainer class which is then instantiated for each liquid template render run.
   #
-  # One of the strainer's responsibilities is to keep malicious method calls out
+  # The Strainer only allows method calls defined in filters given to it via Strainer.global_filter,
-  class Strainer < parent_object #:nodoc:
+  # Context#add_filters or Template.register_filter
-    INTERNAL_METHOD = /^__/
+  class Strainer #:nodoc:
-    @@required_methods = Set.new([:__id__, :__send__, :respond_to?, :extend, :methods, :class, :object_id])
+    @@global_strainer = Class.new(Strainer) do
-
+      @filter_methods = Set.new
-    # Ruby 1.9.2 introduces Object#respond_to_missing?, which is invoked by Object#respond_to?
+    end
-    @@required_methods << :respond_to_missing? if Object.respond_to? :respond_to_missing?
+    @@strainer_class_cache = Hash.new do |hash, filters|
-
+      hash[filters] = Class.new(@@global_strainer) do
-    @@filters = {}
+        @filter_methods = @@global_strainer.filter_methods.dup
+        filters.each { |f| add_filter(f) }
+      end
+    end
 
     def initialize(context)
       @context = context
     end
 
+    class << self
+      attr_reader :filter_methods
+    end
+
+    def self.add_filter(filter)
+      raise ArgumentError, "Expected module but got: #{filter.class}" unless filter.is_a?(Module)
+      unless self.include?(filter)
+        invokable_non_public_methods = (filter.private_instance_methods + filter.protected_instance_methods).select { |m| invokable?(m) }
+        if invokable_non_public_methods.any?
+          raise MethodOverrideError, "Filter overrides registered public methods as non public: #{invokable_non_public_methods.join(', ')}"
+        else
+          send(:include, filter)
+          @filter_methods.merge(filter.public_instance_methods.map(&:to_s))
+        end
+      end
+    end
+
     def self.global_filter(filter)
-      raise ArgumentError, "Passed filter is not a module" unless filter.is_a?(Module)
+      @@strainer_class_cache.clear
-      @@filters[filter.name] = filter
+      @@global_strainer.add_filter(filter)
     end
 
-    def self.create(context)
+    def self.invokable?(method)
-      strainer = Strainer.new(context)
+      @filter_methods.include?(method.to_s)
-      @@filters.each { |k,m| strainer.extend(m) }
-      strainer
     end
 
-    def respond_to?(method, include_private = false)
+    def self.create(context, filters = [])
-      method_name = method.to_s
+      @@strainer_class_cache[filters].new(context)
-      return false if method_name =~ INTERNAL_METHOD
-      return false if @@required_methods.include?(method_name)
-      super
     end
 
-    # remove all standard methods from the bucket so circumvent security
+    def invoke(method, *args)
-    # problems
+      if self.class.invokable?(method)
-    instance_methods.each do |m|
+        send(method, *args)
-      unless @@required_methods.include?(m.to_sym)
+      elsif @context && @context.strict_filters
-        undef_method m
+        raise Liquid::UndefinedFilter, "undefined filter #{method}"
-      end
+      else
+        args.first
+      end
+    rescue ::ArgumentError => e
+      raise Liquid::ArgumentError, e.message, e.backtrace
     end
   end
 end

lib/liquid/tablerowloop_drop.rb

@@ -0,0 +1,62 @@
+module Liquid
+  class TablerowloopDrop < Drop
+    def initialize(length, cols)
+      @length = length
+      @row = 1
+      @col = 1
+      @cols = cols
+      @index = 0
+    end
+
+    attr_reader :length, :col, :row
+
+    def index
+      @index + 1
+    end
+
+    def index0
+      @index
+    end
+
+    def col0
+      @col - 1
+    end
+
+    def rindex
+      @length - @index
+    end
+
+    def rindex0
+      @length - @index - 1
+    end
+
+    def first
+      @index == 0
+    end
+
+    def last
+      @index == @length - 1
+    end
+
+    def col_first
+      @col == 1
+    end
+
+    def col_last
+      @col == @cols
+    end
+
+    protected
+
+    def increment!
+      @index += 1
+
+      if @col == @cols
+        @col = 1
+        @row += 1
+      else
+        @col += 1
+      end
+    end
+  end
+end

lib/liquid/tag.rb

@@ -1,26 +1,43 @@
 module Liquid
-
   class Tag
+    attr_reader :nodelist, :tag_name, :line_number, :parse_context
+    alias_method :options, :parse_context
+    include ParserSwitching
 
-    attr_accessor :nodelist
+    class << self
-
+      def parse(tag_name, markup, tokenizer, options)
-    def initialize(tag_name, markup, tokens)
+        tag = new(tag_name, markup, options)
-      @tag_name   = tag_name
+        tag.parse(tokenizer)
-      @markup     = markup
+        tag
-      parse(tokens)
       end
 
-    def parse(tokens)
+      private :new
+    end
+
+    def initialize(tag_name, markup, parse_context)
+      @tag_name   = tag_name
+      @markup     = markup
+      @parse_context = parse_context
+      @line_number = parse_context.line_number
+    end
+
+    def parse(_tokens)
+    end
+
+    def raw
+      "#{@tag_name} #{@markup}"
     end
 
     def name
       self.class.name.downcase
     end
 
-    def render(context)
+    def render(_context)
-      ''
+      ''.freeze
     end
 
-  end # Tag
+    def blank?
-
+      false
-end # Tag
+    end
+  end
+end

lib/liquid/tags/assign.rb

@@ -1,5 +1,4 @@
 module Liquid
-
   # Assign sets a variable in your template.
   #
   #   {% assign foo = 'monkey' %}
@@ -9,25 +8,52 @@ module Liquid
   #  {{ foo }}
   #
   class Assign < Tag
-    Syntax = /(#{VariableSignature}+)\s*=\s*(#{QuotedFragment}+)/   
+    Syntax = /(#{VariableSignature}+)\s*=\s*(.*)\s*/om
 
-    def initialize(tag_name, markup, tokens)          
+    attr_reader :to, :from
+
+    def initialize(tag_name, markup, options)
+      super
       if markup =~ Syntax
         @to = $1
-        @from = $2
+        @from = Variable.new($2, options)
       else
-        raise SyntaxError.new("Syntax Error in 'assign' - Valid syntax: assign [var] = [source]")
+        raise SyntaxError.new options[:locale].t("errors.syntax.assign".freeze)
       end
-      
-      super      
     end
 
     def render(context)
-       context.scopes.last[@to] = context[@from]
+      val = @from.render(context)
-       ''
+      context.set_root(@to, val)
+      context.resource_limits.assign_score += assign_score_of(val)
+      ''.freeze
     end
 
+    def blank?
+      true
     end
 
-  Template.register_tag('assign', Assign)  
+    private
+
+    def assign_score_of(val)
+      if val.instance_of?(String)
+        val.bytesize
+      elsif val.instance_of?(Array) || val.instance_of?(Hash)
+        sum = 1
+        # Uses #each to avoid extra allocations.
+        val.each { |child| sum += assign_score_of(child) }
+        sum
+      else
+        1
+      end
+    end
+
+    class ParseTreeVisitor < Liquid::ParseTreeVisitor
+      def children
+        [@node.from]
+      end
+    end
+  end
+
+  Template.register_tag('assign'.freeze, Assign)
 end

lib/liquid/tags/break.rb

@@ -0,0 +1,18 @@
+module Liquid
+  # Break tag to be used to break out of a for loop.
+  #
+  # == Basic Usage:
+  #    {% for item in collection %}
+  #      {% if item.condition %}
+  #        {% break %}
+  #      {% endif %}
+  #    {% endfor %}
+  #
+  class Break < Tag
+    def interrupt
+      BreakInterrupt.new
+    end
+  end
+
+  Template.register_tag('break'.freeze, Break)
+end

lib/liquid/tags/capture.rb

@@ -1,5 +1,4 @@
 module Liquid
-
   # Capture stores the result of a block into a variable without rendering it inplace.
   #
   #   {% capture heading %}
@@ -12,24 +11,28 @@ module Liquid
   # in a sidebar or footer.
   #
   class Capture < Block
-    Syntax = /(\w+)/
+    Syntax = /(#{VariableSignature}+)/o
 
-    def initialize(tag_name, markup, tokens)
+    def initialize(tag_name, markup, options)
+      super
       if markup =~ Syntax
         @to = $1
       else
-        raise SyntaxError.new("Syntax Error in 'capture' - Valid syntax: capture [var]")
+        raise SyntaxError.new(options[:locale].t("errors.syntax.capture"))
       end
-
-      super
     end
 
     def render(context)
       output = super
-      context.scopes.last[@to] = output.join
+      context.set_root(@to, output)
-      ''
+      context.resource_limits.assign_score += output.bytesize
+      ''.freeze
+    end
+
+    def blank?
+      true
     end
   end
 
-  Template.register_tag('capture', Capture)
+  Template.register_tag('capture'.freeze, Capture)
 end

lib/liquid/tags/case.rb

@@ -1,26 +1,37 @@
 module Liquid
   class Case < Block
-    Syntax     = /(#{QuotedFragment})/
+    Syntax     = /(#{QuotedFragment})/o
-    WhenSyntax = /(#{QuotedFragment})(?:(?:\s+or\s+|\s*\,\s*)(#{QuotedFragment}.*))?/
+    WhenSyntax = /(#{QuotedFragment})(?:(?:\s+or\s+|\s*\,\s*)(#{QuotedFragment}.*))?/om
 
-    def initialize(tag_name, markup, tokens)      
+    attr_reader :blocks, :left
+
+    def initialize(tag_name, markup, options)
+      super
       @blocks = []
 
       if markup =~ Syntax
-        @left = $1
+        @left = Expression.parse($1)
       else
-        raise SyntaxError.new("Syntax Error in tag 'case' - Valid syntax: case [condition]")
+        raise SyntaxError.new(options[:locale].t("errors.syntax.case".freeze))
+      end
     end
 
-      super
+    def parse(tokens)
+      body = BlockBody.new
+      while parse_body(body, tokens)
+        body = @blocks.last.attachment
+      end
+    end
+
+    def nodelist
+      @blocks.map(&:attachment)
     end
 
     def unknown_tag(tag, markup, tokens)
-      @nodelist = []
       case tag
-      when 'when'
+      when 'when'.freeze
         record_when_condition(markup)
-      when 'else'
+      when 'else'.freeze
         record_else_condition(markup)
       else
         super
@@ -28,56 +39,55 @@ module Liquid
     end
 
     def render(context)
-      context.stack do          
       execute_else_block = true
 
-        @blocks.inject([]) do |output, block|
+      output = ''
-      
+      @blocks.each do |block|
         if block.else?
-            
+          return block.attachment.render(context) if execute_else_block
-            return render_all(block.attachment, context) if execute_else_block
-            
         elsif block.evaluate(context)
-            
           execute_else_block = false
-            output += render_all(block.attachment, context)                    
+          output << block.attachment.render(context)
+        end
       end
 
       output
     end
-      end          
-    end
 
     private
 
     def record_when_condition(markup)
+      body = BlockBody.new
+
       while markup
-      	# Create a new nodelist and assign it to the new block
+        unless markup =~ WhenSyntax
-      	if not markup =~ WhenSyntax
+          raise SyntaxError.new(options[:locale].t("errors.syntax.case_invalid_when".freeze))
-      	  raise SyntaxError.new("Syntax Error in tag 'case' - Valid when condition: {% when [condition] [or condition2...] %} ")
         end
 
         markup = $2
 
-      	block = Condition.new(@left, '==', $1)        
+        block = Condition.new(@left, '=='.freeze, Expression.parse($1))
-      	block.attach(@nodelist)
+        block.attach(body)
-      	@blocks.push(block)
+        @blocks << block
       end
     end
 
     def record_else_condition(markup)
-
+      unless markup.strip.empty?
-      if not markup.strip.empty?
+        raise SyntaxError.new(options[:locale].t("errors.syntax.case_invalid_else".freeze))
-        raise SyntaxError.new("Syntax Error in tag 'case' - Valid else condition: {% else %} (no parameters) ")
       end
 
       block = ElseCondition.new
-      block.attach(@nodelist)
+      block.attach(BlockBody.new)
       @blocks << block
     end
 
-        
+    class ParseTreeVisitor < Liquid::ParseTreeVisitor
+      def children
+        [@node.left] + @node.blocks
+      end
+    end
   end
 
-  Template.register_tag('case', Case)
+  Template.register_tag('case'.freeze, Case)
 end

lib/liquid/tags/comment.rb

@@ -1,9 +1,16 @@
 module Liquid
   class Comment < Block
-    def render(context)
+    def render(_context)
-      ''
+      ''.freeze
+    end
+
+    def unknown_tag(_tag, _markup, _tokens)
+    end
+
+    def blank?
+      true
     end
   end
 
-  Template.register_tag('comment', Comment)
+  Template.register_tag('comment'.freeze, Comment)
 end

lib/liquid/tags/continue.rb

@@ -0,0 +1,18 @@
+module Liquid
+  # Continue tag to be used to break out of a for loop.
+  #
+  # == Basic Usage:
+  #    {% for item in collection %}
+  #      {% if item.condition %}
+  #        {% continue %}
+  #      {% endif %}
+  #    {% endfor %}
+  #
+  class Continue < Tag
+    def interrupt
+      ContinueInterrupt.new
+    end
+  end
+
+  Template.register_tag('continue'.freeze, Continue)
+end

lib/liquid/tags/cycle.rb

@@ -1,5 +1,4 @@
 module Liquid
-  
   # Cycle is usually used within a loop to alternate between values, like colors or DOM classes.
   #
   #   {% for item in items %}
@@ -13,46 +12,51 @@ module Liquid
   #    <div class="green"> Item five</div>
   #
   class Cycle < Tag
-    SimpleSyntax = /^#{QuotedFragment}+/        
+    SimpleSyntax = /\A#{QuotedFragment}+/o
-    NamedSyntax  = /^(#{QuotedFragment})\s*\:\s*(.*)/
+    NamedSyntax  = /\A(#{QuotedFragment})\s*\:\s*(.*)/om
 
-    def initialize(tag_name, markup, tokens)      
+    attr_reader :variables
+
+    def initialize(tag_name, markup, options)
+      super
       case markup
       when NamedSyntax
         @variables = variables_from_string($2)
-      	@name = $1
+        @name = Expression.parse($1)
       when SimpleSyntax
         @variables = variables_from_string(markup)
-      	@name = "'#{@variables.to_s}'"
+        @name = @variables.to_s
       else
-        raise SyntaxError.new("Syntax Error in 'cycle' - Valid syntax: cycle [name :] var [, var2, var3 ...]")
+        raise SyntaxError.new(options[:locale].t("errors.syntax.cycle".freeze))
       end
-      super    
     end
 
     def render(context)
-      context.registers[:cycle] ||= Hash.new(0)
+      context.registers[:cycle] ||= {}
 
-      context.stack do
+      key = context.evaluate(@name)
-        key = context[@name]	
+      iteration = context.registers[:cycle][key].to_i
-        iteration = context.registers[:cycle][key]
+      result = context.evaluate(@variables[iteration])
-        result = context[@variables[iteration]]
       iteration += 1
       iteration  = 0 if iteration >= @variables.size
       context.registers[:cycle][key] = iteration
       result
     end
-    end
 
     private
 
     def variables_from_string(markup)
       markup.split(',').collect do |var|
-    	  var =~ /\s*(#{QuotedFragment})\s*/
+        var =~ /\s*(#{QuotedFragment})\s*/o
-    	  $1 ? $1 : nil
+        $1 ? Expression.parse($1) : nil
       end.compact
     end
 
+    class ParseTreeVisitor < Liquid::ParseTreeVisitor
+      def children
+        Array(@node.variables)
+      end
+    end
   end
 
   Template.register_tag('cycle', Cycle)

lib/liquid/tags/decrement.rb

@@ -0,0 +1,35 @@
+module Liquid
+  # decrement is used in a place where one needs to insert a counter
+  #     into a template, and needs the counter to survive across
+  #     multiple instantiations of the template.
+  #     NOTE: decrement is a pre-decrement, --i,
+  #           while increment is post:      i++.
+  #
+  #     (To achieve the survival, the application must keep the context)
+  #
+  #     if the variable does not exist, it is created with value 0.
+
+  #   Hello: {% decrement variable %}
+  #
+  # gives you:
+  #
+  #    Hello: -1
+  #    Hello: -2
+  #    Hello: -3
+  #
+  class Decrement < Tag
+    def initialize(tag_name, markup, options)
+      super
+      @variable = markup.strip
+    end
+
+    def render(context)
+      value = context.environments.first[@variable] ||= 0
+      value -= 1
+      context.environments.first[@variable] = value
+      value.to_s
+    end
+  end
+
+  Template.register_tag('decrement'.freeze, Decrement)
+end

lib/liquid/tags/for.rb

@@ -1,5 +1,4 @@
 module Liquid
-
   # "For" iterates over an array or collection.
   # Several useful variables are available to you within the loop.
   #
@@ -13,6 +12,8 @@ module Liquid
   #      <div {% if forloop.first %}class="first"{% endif %}>
   #        Item {{ forloop.index }}: {{ item.name }}
   #      </div>
+  #    {% else %}
+  #      There is nothing in the collection.
   #    {% endfor %}
   #
   # You can also define a limit and offset much like SQL.  Remember
@@ -22,7 +23,7 @@ module Liquid
   #      {{ item.name }}
   #    {% end %}
   #
-  #  To reverse the for loop simply use {% for item in collection reversed %}
+  #  To reverse the for loop simply use {% for item in collection reversed %} (note that the flag's spelling is different to the filter `reverse`)
   #
   # == Available variables:
   #
@@ -40,97 +41,175 @@ module Liquid
   #                   where 0 is the last item.
   # forloop.first:: Returns true if the item is the first item.
   # forloop.last:: Returns true if the item is the last item.
+  # forloop.parentloop:: Provides access to the parent loop, if present.
   #
   class For < Block
-    Syntax = /(\w+)\s+in\s+(#{QuotedFragment}+)\s*(reversed)?/   
+    Syntax = /\A(#{VariableSegment}+)\s+in\s+(#{QuotedFragment}+)\s*(reversed)?/o
 
-    def initialize(tag_name, markup, tokens)
+    attr_reader :collection_name, :variable_name, :limit, :from
-      if markup =~ Syntax
-        @variable_name = $1
-        @collection_name = $2
-        @name = "#{$1}-#{$2}"           
-        @reversed = $3             
-        @attributes = {}
-        markup.scan(TagAttributes) do |key, value|
-          @attributes[key] = value
-        end        
-      else
-        raise SyntaxError.new("Syntax Error in 'for loop' - Valid syntax: for [item] in [collection]")
-      end
 
+    def initialize(tag_name, markup, options)
       super
+      @from = @limit = nil
+      parse_with_selected_parser(markup)
+      @for_block = BlockBody.new
+      @else_block = nil
+    end
+
+    def parse(tokens)
+      return unless parse_body(@for_block, tokens)
+      parse_body(@else_block, tokens)
+    end
+
+    def nodelist
+      @else_block ? [@for_block, @else_block] : [@for_block]
+    end
+
+    def unknown_tag(tag, markup, tokens)
+      return super unless tag == 'else'.freeze
+      @else_block = BlockBody.new
     end
 
     def render(context)
-      context.registers[:for] ||= Hash.new(0)
+      segment = collection_segment(context)
 
-      collection = context[@collection_name]
+      if segment.empty?
+        render_else(context)
+      else
+        render_segment(context, segment)
+      end
+    end
+
+    protected
+
+    def lax_parse(markup)
+      if markup =~ Syntax
+        @variable_name = $1
+        collection_name = $2
+        @reversed = !!$3
+        @name = "#{@variable_name}-#{collection_name}"
+        @collection_name = Expression.parse(collection_name)
+        markup.scan(TagAttributes) do |key, value|
+          set_attribute(key, value)
+        end
+      else
+        raise SyntaxError.new(options[:locale].t("errors.syntax.for".freeze))
+      end
+    end
+
+    def strict_parse(markup)
+      p = Parser.new(markup)
+      @variable_name = p.consume(:id)
+      raise SyntaxError.new(options[:locale].t("errors.syntax.for_invalid_in".freeze)) unless p.id?('in'.freeze)
+      collection_name = p.expression
+      @name = "#{@variable_name}-#{collection_name}"
+      @collection_name = Expression.parse(collection_name)
+      @reversed = p.id?('reversed'.freeze)
+
+      while p.look(:id) && p.look(:colon, 1)
+        unless attribute = p.id?('limit'.freeze) || p.id?('offset'.freeze)
+          raise SyntaxError.new(options[:locale].t("errors.syntax.for_invalid_attribute".freeze))
+        end
+        p.consume
+        set_attribute(attribute, p.expression)
+      end
+      p.consume(:end_of_string)
+    end
+
+    private
+
+    def collection_segment(context)
+      offsets = context.registers[:for] ||= {}
+
+      from = if @from == :continue
+        offsets[@name].to_i
+      else
+        from_value = context.evaluate(@from)
+        if from_value.nil?
+          0
+        else
+          Utils.to_integer(from_value)
+        end
+      end
+
+      collection = context.evaluate(@collection_name)
       collection = collection.to_a if collection.is_a?(Range)
 
-      return '' unless collection.respond_to?(:each) 
+      limit_value = context.evaluate(@limit)
-                                                 
+      to = if limit_value.nil?
-      from = if @attributes['offset'] == 'continue'
+        nil
-        context.registers[:for][@name].to_i
       else
-        context[@attributes['offset']].to_i
+        Utils.to_integer(limit_value) + from
       end
 
-      limit = context[@attributes['limit']]
+      segment = Utils.slice_collection(collection, from, to)
-      to    = limit ? limit.to_i + from : nil  
-          
-                       
-      segment = slice_collection_using_each(collection, from, to)      
-      
-      return '' if segment.empty?
-      
       segment.reverse! if @reversed
 
-      result = []
+      offsets[@name] = from + segment.length
 
+      segment
+    end
+
+    def render_segment(context, segment)
+      for_stack = context.registers[:for_stack] ||= []
       length = segment.length
 
-      # Store our progress through the collection for the continue flag
+      result = ''
-      context.registers[:for][@name] = from + segment.length
 
-      context.stack do 
+      context.stack('forloop', @variable_name) do
-        segment.each_with_index do |item, index|     
+        loop_vars = Liquid::ForloopDrop.new(@name, length, for_stack[-1])
-          context[@variable_name] = item
-          context['forloop'] = {
-            'name'    => @name,
-            'length'  => length,
-            'index'   => index + 1, 
-            'index0'  => index, 
-            'rindex'  => length - index,
-            'rindex0' => length - index -1,
-            'first'   => (index == 0),
-            'last'    => (index == length - 1) }
 
-          result << render_all(@nodelist, context)
+        for_stack.push(loop_vars)
+
+        begin
+          context['forloop'.freeze] = loop_vars
+          level = context.create_level(@variable_name)
+
+          segment.each do |item|
+            context.set_level(@variable_name, item, level)
+            result << @for_block.render(context)
+            loop_vars.send(:increment!)
+            # Handle any interrupts if they exist.
+            if context.interrupt?
+              interrupt = context.pop_interrupt
+              break if interrupt.is_a? BreakInterrupt
+              next if interrupt.is_a? ContinueInterrupt
             end
           end
+          context.unset(@variable_name)
+          context.unset('forloop'.freeze)
+        ensure
+
+          for_stack.pop
+        end
+      end
+
       result
     end
 
-    def slice_collection_using_each(collection, from, to)       
+    def set_attribute(key, expr)
-      segments = []      
+      case key
-      index = 0      
+      when 'offset'.freeze
-      yielded = 0
+        @from = if expr == 'continue'.freeze
-      collection.each do |item|         
+          :continue
-                
+        else
-        if to && to <= index
+          Expression.parse(expr)
-          break
         end
-        
+      when 'limit'.freeze
-        if from <= index                               
+        @limit = Expression.parse(expr)
-          segments << item
-        end                    
-                
-        index += 1
-      end    
-
-      segments
       end
     end
 
-  Template.register_tag('for', For)
+    def render_else(context)
+      @else_block ? @else_block.render(context) : ''.freeze
+    end
+
+    class ParseTreeVisitor < Liquid::ParseTreeVisitor
+      def children
+        (super + [@node.limit, @node.from, @node.collection_name]).compact
+      end
+    end
+  end
+
+  Template.register_tag('for'.freeze, For)
 end

lib/liquid/tags/if.rb

@@ -1,5 +1,4 @@
 module Liquid
-
   # If is the conditional block
   #
   #   {% if user.admin %}
@@ -10,22 +9,30 @@ module Liquid
   #
   #    There are {% if count < 5 %} less {% else %} more {% endif %} items than you need.
   #
-  #
   class If < Block
-    SyntaxHelp = "Syntax Error in tag 'if' - Valid syntax: if [expression]"
+    Syntax = /(#{QuotedFragment})\s*([=!<>a-z_]+)?\s*(#{QuotedFragment})?/o
-    Syntax = /(#{QuotedFragment})\s*([=!<>a-z_]+)?\s*(#{QuotedFragment})?/
+    ExpressionsAndOperators = /(?:\b(?:\s?and\s?|\s?or\s?)\b|(?:\s*(?!\b(?:\s?and\s?|\s?or\s?)\b)(?:#{QuotedFragment}|\S+)\s*)+)/o
-    ExpressionsAndOperators = /(?:\b(?:\s?and\s?|\s?or\s?)\b|(?:\s*(?!\b(?:\s?and\s?|\s?or\s?)\b)(?:#{QuotedFragment}|\S+)\s*)+)/
+    BOOLEAN_OPERATORS = %w(and or).freeze
 
-    def initialize(tag_name, markup, tokens)
+    attr_reader :blocks
-      @blocks = []
-
-      push_block('if', markup)
 
+    def initialize(tag_name, markup, options)
       super
+      @blocks = []
+      push_block('if'.freeze, markup)
+    end
+
+    def nodelist
+      @blocks.map(&:attachment)
+    end
+
+    def parse(tokens)
+      while parse_body(@blocks.last.attachment, tokens)
+      end
     end
 
     def unknown_tag(tag, markup, tokens)
-      if ['elsif', 'else'].include?(tag)
+      if ['elsif'.freeze, 'else'.freeze].include?(tag)
         push_block(tag, markup)
       else
         super
@@ -33,47 +40,81 @@ module Liquid
     end
 
     def render(context)
-      context.stack do
       @blocks.each do |block|
         if block.evaluate(context)
-            return render_all(block.attachment, context)
+          return block.attachment.render(context)
         end
       end
-        ''
+      ''.freeze
-      end
     end
 
     private
 
     def push_block(tag, markup)
-        block = if tag == 'else'
+      block = if tag == 'else'.freeze
         ElseCondition.new
       else
+        parse_with_selected_parser(markup)
+      end
 
-          expressions = markup.scan(ExpressionsAndOperators).reverse
+      @blocks.push(block)
-          raise(SyntaxError, SyntaxHelp) unless expressions.shift =~ Syntax
+      block.attach(BlockBody.new)
+    end
 
-          condition = Condition.new($1, $2, $3)
+    def lax_parse(markup)
+      expressions = markup.scan(ExpressionsAndOperators)
+      raise(SyntaxError.new(options[:locale].t("errors.syntax.if".freeze))) unless expressions.pop =~ Syntax
 
-          while not expressions.empty?
+      condition = Condition.new(Expression.parse($1), $2, Expression.parse($3))
-            operator = (expressions.shift).to_s.strip
 
-            raise(SyntaxError, SyntaxHelp) unless expressions.shift.to_s =~ Syntax
+      until expressions.empty?
+        operator = expressions.pop.to_s.strip
 
-            new_condition = Condition.new($1, $2, $3)
+        raise(SyntaxError.new(options[:locale].t("errors.syntax.if".freeze))) unless expressions.pop.to_s =~ Syntax
-            new_condition.send(operator.to_sym, condition)
+
+        new_condition = Condition.new(Expression.parse($1), $2, Expression.parse($3))
+        raise(SyntaxError.new(options[:locale].t("errors.syntax.if".freeze))) unless BOOLEAN_OPERATORS.include?(operator)
+        new_condition.send(operator, condition)
         condition = new_condition
       end
 
       condition
     end
 
-        @blocks.push(block)
+    def strict_parse(markup)
-        @nodelist = block.attach(Array.new)
+      p = Parser.new(markup)
+      condition = parse_binary_comparisons(p)
+      p.consume(:end_of_string)
+      condition
     end
 
-
+    def parse_binary_comparisons(p)
+      condition = parse_comparison(p)
+      first_condition = condition
+      while op = (p.id?('and'.freeze) || p.id?('or'.freeze))
+        child_condition = parse_comparison(p)
+        condition.send(op, child_condition)
+        condition = child_condition
+      end
+      first_condition
     end
 
-  Template.register_tag('if', If)
+    def parse_comparison(p)
+      a = Expression.parse(p.expression)
+      if op = p.consume?(:comparison)
+        b = Expression.parse(p.expression)
+        Condition.new(a, op, b)
+      else
+        Condition.new(a)
+      end
+    end
+
+    class ParseTreeVisitor < Liquid::ParseTreeVisitor
+      def children
+        @node.blocks
+      end
+    end
+  end
+
+  Template.register_tag('if'.freeze, If)
 end

lib/liquid/tags/ifchanged.rb

@@ -1,20 +1,16 @@
 module Liquid
   class Ifchanged < Block
-            
     def render(context)
-      context.stack do 
+      output = super
-        
-        output = render_all(@nodelist, context)
 
       if output != context.registers[:ifchanged]
         context.registers[:ifchanged] = output
         output
       else
-          ''
+        ''.freeze
-        end              
       end
     end
   end
 
-  Template.register_tag('ifchanged', Ifchanged)  
+  Template.register_tag('ifchanged'.freeze, Ifchanged)
 end

lib/liquid/tags/include.rb

@@ -1,56 +1,124 @@
 module Liquid
+  # Include allows templates to relate with other templates
+  #
+  # Simply include another template:
+  #
+  #   {% include 'product' %}
+  #
+  # Include a template with a local variable:
+  #
+  #   {% include 'product' with products[0] %}
+  #
+  # Include a template for a collection:
+  #
+  #   {% include 'product' for products %}
+  #
   class Include < Tag
-    Syntax = /(#{QuotedFragment}+)(\s+(?:with|for)\s+(#{QuotedFragment}+))?/
+    Syntax = /(#{QuotedFragment}+)(\s+(?:with|for)\s+(#{QuotedFragment}+))?/o
+
+    attr_reader :template_name_expr, :variable_name_expr, :attributes
+
+    def initialize(tag_name, markup, options)
+      super
 
-    def initialize(tag_name, markup, tokens)      
       if markup =~ Syntax
 
-        @template_name = $1        
+        template_name = $1
-        @variable_name = $3
+        variable_name = $3
+
+        @variable_name_expr = variable_name ? Expression.parse(variable_name) : nil
+        @template_name_expr = Expression.parse(template_name)
         @attributes = {}
 
         markup.scan(TagAttributes) do |key, value|
-          @attributes[key] = value
+          @attributes[key] = Expression.parse(value)
         end
 
       else
-        raise SyntaxError.new("Error in tag 'include' - Valid syntax: include '[template]' (with|for) [object|collection]")
+        raise SyntaxError.new(options[:locale].t("errors.syntax.include".freeze))
+      end
     end
 
-      super
+    def parse(_tokens)
-    end
-  
-    def parse(tokens)      
     end
 
     def render(context)
-      file_system = context.registers[:file_system] || Liquid::Template.file_system
+      template_name = context.evaluate(@template_name_expr)
-      source  = file_system.read_template_file(context[@template_name])      
+      raise ArgumentError.new(options[:locale].t("errors.argument.include")) unless template_name
-      partial = Liquid::Template.parse(source)      
 
-      variable = context[@variable_name || @template_name[1..-2]]
+      partial = load_cached_partial(template_name, context)
+      context_variable_name = template_name.split('/'.freeze).last
 
-      context.stack do
+      variable = if @variable_name_expr
+        context.evaluate(@variable_name_expr)
+      else
+        context.find_variable(template_name, raise_on_not_found: false)
+      end
+
+      old_template_name = context.template_name
+      old_partial = context.partial
+      begin
+        context.template_name = template_name
+        context.partial = true
+        context.stack(context_variable_name, *@attributes.keys) do
           @attributes.each do |key, value|
-          context[key] = context[value]
+            context[key] = context.evaluate(value)
           end
 
           if variable.is_a?(Array)
-          
+            variable.collect do |var|
-          variable.collect do |variable|            
+              context[context_variable_name] = var
-            context[@template_name[1..-2]] = variable
               partial.render(context)
             end
-
           else
-                    
+            context[context_variable_name] = variable
-          context[@template_name[1..-2]] = variable
             partial.render(context)
-          
           end
         end
+      ensure
+        context.template_name = old_template_name
+        context.partial = old_partial
+      end
+    end
+
+    private
+
+    alias_method :parse_context, :options
+    private :parse_context
+
+    def load_cached_partial(template_name, context)
+      cached_partials = context.registers[:cached_partials] || {}
+
+      if cached = cached_partials[template_name]
+        return cached
+      end
+      source = read_template_from_file_system(context)
+      begin
+        parse_context.partial = true
+        partial = Liquid::Template.parse(source, parse_context)
+      ensure
+        parse_context.partial = false
+      end
+      cached_partials[template_name] = partial
+      context.registers[:cached_partials] = cached_partials
+      partial
+    end
+
+    def read_template_from_file_system(context)
+      file_system = context.registers[:file_system] || Liquid::Template.file_system
+
+      file_system.read_template_file(context.evaluate(@template_name_expr))
+    end
+
+    class ParseTreeVisitor < Liquid::ParseTreeVisitor
+      def children
+        [
+          @node.template_name_expr,
+          @node.variable_name_expr
+        ] + @node.attributes.values
+      end
     end
   end
 
-  Template.register_tag('include', Include)  
+  Template.register_tag('include'.freeze, Include)
 end

lib/liquid/tags/increment.rb

@@ -0,0 +1,31 @@
+module Liquid
+  # increment is used in a place where one needs to insert a counter
+  #     into a template, and needs the counter to survive across
+  #     multiple instantiations of the template.
+  #     (To achieve the survival, the application must keep the context)
+  #
+  #     if the variable does not exist, it is created with value 0.
+  #
+  #   Hello: {% increment variable %}
+  #
+  # gives you:
+  #
+  #    Hello: 0
+  #    Hello: 1
+  #    Hello: 2
+  #
+  class Increment < Tag
+    def initialize(tag_name, markup, options)
+      super
+      @variable = markup.strip
+    end
+
+    def render(context)
+      value = context.environments.first[@variable] ||= 0
+      context.environments.first[@variable] = value + 1
+      value.to_s
+    end
+  end
+
+  Template.register_tag('increment'.freeze, Increment)
+end

lib/liquid/tags/literal.rb

@@ -1,42 +0,0 @@
-module Liquid
-
-  class Literal < Block
-
-    # Class methods
-
-    # Converts a shorthand Liquid literal into its long representation.
-    #
-    # Currently the Template parser only knows how to handle the long version.
-    # So, it always checks if it is in the presence of a literal, in which case it gets converted through this method.
-    #
-    # Example:
-    #   Liquid::Literal "{{{ hello world }}}" #=> "{% literal %} hello world {% endliteral %}"
-    def self.from_shorthand(literal)
-      literal =~ LiteralShorthand ? "{% literal %}#{$1}{% endliteral %}" : literal
-    end
-
-    # Public instance methods
-
-    def parse(tokens) # :nodoc:
-      @nodelist ||= []
-      @nodelist.clear
-
-      while token = tokens.shift
-        if token =~ FullToken && block_delimiter == $1
-          end_tag
-          return
-        else
-          @nodelist << token
-        end
-      end
-
-      # Make sure that its ok to end parsing in the current block.
-      # Effectively this method will throw and exception unless the current block is
-      # of type Document
-      assert_missing_delimitation!
-    end # parse
-
-  end
-
-  Template.register_tag('literal', Literal)
-end

lib/liquid/tags/raw.rb

@@ -0,0 +1,47 @@
+module Liquid
+  class Raw < Block
+    Syntax = /\A\s*\z/
+    FullTokenPossiblyInvalid = /\A(.*)#{TagStart}\s*(\w+)\s*(.*)?#{TagEnd}\z/om
+
+    def initialize(tag_name, markup, parse_context)
+      super
+
+      ensure_valid_markup(tag_name, markup, parse_context)
+    end
+
+    def parse(tokens)
+      @body = ''
+      while token = tokens.shift
+        if token =~ FullTokenPossiblyInvalid
+          @body << $1 if $1 != "".freeze
+          return if block_delimiter == $2
+        end
+        @body << token unless token.empty?
+      end
+
+      raise SyntaxError.new(parse_context.locale.t("errors.syntax.tag_never_closed".freeze, block_name: block_name))
+    end
+
+    def render(_context)
+      @body
+    end
+
+    def nodelist
+      [@body]
+    end
+
+    def blank?
+      @body.empty?
+    end
+
+    protected
+
+    def ensure_valid_markup(tag_name, markup, parse_context)
+      unless markup =~ Syntax
+        raise SyntaxError.new(parse_context.locale.t("errors.syntax.tag_unexpected_args".freeze, tag: tag_name))
+      end
+    end
+  end
+
+  Template.register_tag('raw'.freeze, Raw)
+end

lib/liquid/tags/table_row.rb

@@ -0,0 +1,62 @@
+module Liquid
+  class TableRow < Block
+    Syntax = /(\w+)\s+in\s+(#{QuotedFragment}+)/o
+
+    attr_reader :variable_name, :collection_name, :attributes
+
+    def initialize(tag_name, markup, options)
+      super
+      if markup =~ Syntax
+        @variable_name = $1
+        @collection_name = Expression.parse($2)
+        @attributes = {}
+        markup.scan(TagAttributes) do |key, value|
+          @attributes[key] = Expression.parse(value)
+        end
+      else
+        raise SyntaxError.new(options[:locale].t("errors.syntax.table_row".freeze))
+      end
+    end
+
+    def render(context)
+      collection = context.evaluate(@collection_name) or return ''.freeze
+
+      from = @attributes.key?('offset'.freeze) ? context.evaluate(@attributes['offset'.freeze]).to_i : 0
+      to = @attributes.key?('limit'.freeze) ? from + context.evaluate(@attributes['limit'.freeze]).to_i : nil
+
+      collection = Utils.slice_collection(collection, from, to)
+
+      length = collection.length
+
+      cols = context.evaluate(@attributes['cols'.freeze]).to_i
+
+      result = "<tr class=\"row1\">\n"
+      context.stack('tablerowloop', @variable_name) do
+        tablerowloop = Liquid::TablerowloopDrop.new(length, cols)
+        context['tablerowloop'.freeze] = tablerowloop
+
+        collection.each do |item|
+          context[@variable_name] = item
+
+          result << "<td class=\"col#{tablerowloop.col}\">" << super << '</td>'
+
+          if tablerowloop.col_last && !tablerowloop.last
+            result << "</tr>\n<tr class=\"row#{tablerowloop.row + 1}\">"
+          end
+
+          tablerowloop.send(:increment!)
+        end
+      end
+      result << "</tr>\n"
+      result
+    end
+
+    class ParseTreeVisitor < Liquid::ParseTreeVisitor
+      def children
+        super + @node.attributes.values + [@node.collection_name]
+      end
+    end
+  end
+
+  Template.register_tag('tablerow'.freeze, TableRow)
+end

lib/liquid/tags/unless.rb

@@ -1,33 +1,28 @@
-require File.dirname(__FILE__) + '/if'
+require_relative 'if'
 
 module Liquid
-
   # Unless is a conditional just like 'if' but works on the inverse logic.
   #
-  #   {% unless x < 0 %} x is greater than zero {% end %}
+  #   {% unless x < 0 %} x is greater than zero {% endunless %}
   #
   class Unless < If
     def render(context)
-      context.stack do
-        
       # First condition is interpreted backwards ( if not )
-        block = @blocks.first
+      first_block = @blocks.first
-        unless block.evaluate(context)
+      unless first_block.evaluate(context)
-          return render_all(block.attachment, context)            
+        return first_block.attachment.render(context)
       end
 
       # After the first condition unless works just like if
       @blocks[1..-1].each do |block|
         if block.evaluate(context)
-            return render_all(block.attachment, context)            
+          return block.attachment.render(context)
         end
       end
 
-        ''
+      ''.freeze
-      end
     end
   end
 
-
+  Template.register_tag('unless'.freeze, Unless)
-  Template.register_tag('unless', Unless)
 end

lib/liquid/template.rb

@@ -1,5 +1,4 @@
 module Liquid
-
   # Templates are central to liquid.
   # Interpretating templates is a two step process. First you compile the
   # source code you got. During compile time some extensive error checking is performed.
@@ -15,9 +14,66 @@ module Liquid
   #
   class Template
     attr_accessor :root
+    attr_reader :resource_limits, :warnings
+
     @@file_system = BlankFileSystem.new
 
+    class TagRegistry
+      include Enumerable
+
+      def initialize
+        @tags = {}
+        @cache = {}
+      end
+
+      def [](tag_name)
+        return nil unless @tags.key?(tag_name)
+        return @cache[tag_name] if Liquid.cache_classes
+
+        lookup_class(@tags[tag_name]).tap { |o| @cache[tag_name] = o }
+      end
+
+      def []=(tag_name, klass)
+        @tags[tag_name]  = klass.name
+        @cache[tag_name] = klass
+      end
+
+      def delete(tag_name)
+        @tags.delete(tag_name)
+        @cache.delete(tag_name)
+      end
+
+      def each(&block)
+        @tags.each(&block)
+      end
+
+      private
+
+      def lookup_class(name)
+        name.split("::").reject(&:empty?).reduce(Object) { |scope, const| scope.const_get(const) }
+      end
+    end
+
+    attr_reader :profiler
+
     class << self
+      # Sets how strict the parser should be.
+      # :lax acts like liquid 2.5 and silently ignores malformed tags in most cases.
+      # :warn is the default and will give deprecation warnings when invalid syntax is used.
+      # :strict will enforce correct syntax.
+      attr_writer :error_mode
+
+      # Sets how strict the taint checker should be.
+      # :lax is the default, and ignores the taint flag completely
+      # :warn adds a warning, but does not interrupt the rendering
+      # :error raises an error when tainted output is used
+      attr_writer :taint_mode
+
+      attr_accessor :default_exception_renderer
+      Template.default_exception_renderer = lambda do |exception|
+        exception
+      end
+
       def file_system
         @@file_system
       end
@@ -31,7 +87,15 @@ module Liquid
       end
 
       def tags
-        @tags ||= {}
+        @tags ||= TagRegistry.new
+      end
+
+      def error_mode
+        @error_mode ||= :lax
+      end
+
+      def taint_mode
+        @taint_mode ||= :lax
       end
 
       # Pass a module with filter methods which should be available
@@ -40,22 +104,33 @@ module Liquid
         Strainer.global_filter(mod)
       end
 
+      def default_resource_limits
+        @default_resource_limits ||= {}
+      end
+
       # creates a new <tt>Template</tt> object from liquid source code
-      def parse(source)
+      # To enable profiling, pass in <tt>profile: true</tt> as an option.
+      # See Liquid::Profiler for more information
+      def parse(source, options = {})
         template = Template.new
-        template.parse(source)
+        template.parse(source, options)
-        template
       end
     end
 
-    # creates a new <tt>Template</tt> from an array of tokens. Use <tt>Template.parse</tt> instead
     def initialize
+      @rethrow_errors = false
+      @resource_limits = ResourceLimits.new(self.class.default_resource_limits)
     end
 
     # Parse source code.
     # Returns self for easy chaining
-    def parse(source)
+    def parse(source, options = {})
-      @root = Document.new(tokenize(Liquid::Literal.from_shorthand(source)))
+      @options = options
+      @profiling = options[:profile]
+      @line_numbers = options[:line_numbers] || @profiling
+      parse_context = options.is_a?(ParseContext) ? options : ParseContext.new(options)
+      @root = Document.parse(tokenize(source), parse_context)
+      @warnings = parse_context.warnings
       self
     end
 
@@ -80,6 +155,9 @@ module Liquid
     # if you use the same filters over and over again consider registering them globally
     # with <tt>Template.register_filter</tt>
     #
+    # if profiling was enabled in <tt>Template#parse</tt> then the resulting profiling information
+    # will be available via <tt>Template#profiler</tt>
+    #
     # Following options can be passed:
     #
     #  * <tt>filters</tt> : array with local filters
@@ -87,63 +165,90 @@ module Liquid
     #    filters and tags and might be useful to integrate liquid more with its host application
     #
     def render(*args)
-      return '' if @root.nil?
+      return ''.freeze if @root.nil?
 
       context = case args.first
       when Liquid::Context
-        args.shift
+        c = args.shift
+
+        if @rethrow_errors
+          c.exception_renderer = ->(e) { raise }
+        end
+
+        c
+      when Liquid::Drop
+        drop = args.shift
+        drop.context = Context.new([drop, assigns], instance_assigns, registers, @rethrow_errors, @resource_limits)
       when Hash
-        Context.new([args.shift, assigns], instance_assigns, registers, @rethrow_errors)
+        Context.new([args.shift, assigns], instance_assigns, registers, @rethrow_errors, @resource_limits)
       when nil
-        Context.new(assigns, instance_assigns, registers, @rethrow_errors)
+        Context.new(assigns, instance_assigns, registers, @rethrow_errors, @resource_limits)
       else
-        raise ArgumentError, "Expect Hash or Liquid::Context as parameter"
+        raise ArgumentError, "Expected Hash or Liquid::Context as parameter"
       end
 
       case args.last
       when Hash
         options = args.pop
 
-        if options[:registers].is_a?(Hash)
+        registers.merge!(options[:registers]) if options[:registers].is_a?(Hash)
-          self.registers.merge!(options[:registers])
-        end
 
-        if options[:filters]
+        apply_options_to_context(context, options)
-          context.add_filters(options[:filters])
+      when Module, Array
-        end
-
-      when Module
-        context.add_filters(args.pop)
-      when Array
         context.add_filters(args.pop)
       end
 
+      # Retrying a render resets resource usage
+      context.resource_limits.reset
+
       begin
         # render the nodelist.
-        # for performance reasons we get a array back here. join will make a string out of it
+        # for performance reasons we get an array back here. join will make a string out of it.
-        @root.render(context).join
+        result = with_profiling(context) do
+          @root.render(context)
+        end
+        result.respond_to?(:join) ? result.join : result
+      rescue Liquid::MemoryError => e
+        context.handle_error(e)
       ensure
         @errors = context.errors
       end
     end
 
     def render!(*args)
-      @rethrow_errors = true; render(*args)
+      @rethrow_errors = true
+      render(*args)
     end
 
     private
 
-    # Uses the <tt>Liquid::TemplateParser</tt> regexp to tokenize the passed source
     def tokenize(source)
-      source = source.source if source.respond_to?(:source)
+      Tokenizer.new(source, @line_numbers)
-      return [] if source.to_s.empty?
-      tokens = source.split(TemplateParser)
-
-      # removes the rogue empty element at the beginning of the array
-      tokens.shift if tokens[0] and tokens[0].empty?
-
-      tokens
     end
 
+    def with_profiling(context)
+      if @profiling && !context.partial
+        raise "Profiler not loaded, require 'liquid/profiler' first" unless defined?(Liquid::Profiler)
+
+        @profiler = Profiler.new
+        @profiler.start
+
+        begin
+          yield
+        ensure
+          @profiler.stop
+        end
+      else
+        yield
+      end
+    end
+
+    def apply_options_to_context(context, options)
+      context.add_filters(options[:filters]) if options[:filters]
+      context.global_filter = options[:global_filter] if options[:global_filter]
+      context.exception_renderer = options[:exception_renderer] if options[:exception_renderer]
+      context.strict_variables = options[:strict_variables] if options[:strict_variables]
+      context.strict_filters = options[:strict_filters] if options[:strict_filters]
+    end
   end
 end

lib/liquid/tokenizer.rb

@@ -0,0 +1,31 @@
+module Liquid
+  class Tokenizer
+    attr_reader :line_number
+
+    def initialize(source, line_numbers = false)
+      @source = source
+      @line_number = line_numbers ? 1 : nil
+      @tokens = tokenize
+    end
+
+    def shift
+      token = @tokens.shift
+      @line_number += token.count("\n") if @line_number && token
+      token
+    end
+
+    private
+
+    def tokenize
+      @source = @source.source if @source.respond_to?(:source)
+      return [] if @source.to_s.empty?
+
+      tokens = @source.split(TemplateParser)
+
+      # removes the rogue empty element at the beginning of the array
+      tokens.shift if tokens[0] && tokens[0].empty?
+
+      tokens
+    end
+  end
+end

lib/liquid/utils.rb

@@ -0,0 +1,83 @@
+module Liquid
+  module Utils
+    def self.slice_collection(collection, from, to)
+      if (from != 0 || !to.nil?) && collection.respond_to?(:load_slice)
+        collection.load_slice(from, to)
+      else
+        slice_collection_using_each(collection, from, to)
+      end
+    end
+
+    def self.slice_collection_using_each(collection, from, to)
+      segments = []
+      index = 0
+
+      # Maintains Ruby 1.8.7 String#each behaviour on 1.9
+      if collection.is_a?(String)
+        return collection.empty? ? [] : [collection]
+      end
+      return [] unless collection.respond_to?(:each)
+
+      collection.each do |item|
+        if to && to <= index
+          break
+        end
+
+        if from <= index
+          segments << item
+        end
+
+        index += 1
+      end
+
+      segments
+    end
+
+    def self.to_integer(num)
+      return num if num.is_a?(Integer)
+      num = num.to_s
+      begin
+        Integer(num)
+      rescue ::ArgumentError
+        raise Liquid::ArgumentError, "invalid integer"
+      end
+    end
+
+    def self.to_number(obj)
+      case obj
+      when Float
+        BigDecimal(obj.to_s)
+      when Numeric
+        obj
+      when String
+        (obj.strip =~ /\A-?\d+\.\d+\z/) ? BigDecimal(obj) : obj.to_i
+      else
+        if obj.respond_to?(:to_number)
+          obj.to_number
+        else
+          0
+        end
+      end
+    end
+
+    def self.to_date(obj)
+      return obj if obj.respond_to?(:strftime)
+
+      if obj.is_a?(String)
+        return nil if obj.empty?
+        obj = obj.downcase
+      end
+
+      case obj
+      when 'now'.freeze, 'today'.freeze
+        Time.now
+      when /\A\d+\z/, Integer
+        Time.at(obj.to_i)
+      when String
+        Time.parse(obj)
+      end
+    rescue ::ArgumentError
+      nil
+    end
+  end
+end

lib/liquid/variable.rb

@@ -1,5 +1,4 @@
 module Liquid
-
   # Holds variables. Variables are only loaded "just in time"
   # and are not evaluated as part of the render stage
   #
@@ -11,39 +10,139 @@ module Liquid
   #   {{ user | link }}
   #
   class Variable
-    FilterParser = /(?:#{FilterSeparator}|(?:\s*(?!(?:#{FilterSeparator}))(?:#{QuotedFragment}|\S+)\s*)+)/
+    FilterMarkupRegex = /#{FilterSeparator}\s*(.*)/om
-    attr_accessor :filters, :name
+    FilterParser = /(?:\s+|#{QuotedFragment}|#{ArgumentSeparator})+/o
+    FilterArgsRegex = /(?:#{FilterArgumentSeparator}|#{ArgumentSeparator})\s*((?:\w+\s*\:\s*)?#{QuotedFragment})/o
+    JustTagAttributes = /\A#{TagAttributes}\z/o
+    MarkupWithQuotedFragment = /(#{QuotedFragment})(.*)/om
 
-    def initialize(markup)
+    attr_accessor :filters, :name, :line_number
+    attr_reader :parse_context
+    alias_method :options, :parse_context
+
+    include ParserSwitching
+
+    def initialize(markup, parse_context)
       @markup  = markup
       @name    = nil
+      @parse_context = parse_context
+      @line_number = parse_context.line_number
+
+      parse_with_selected_parser(markup)
+    end
+
+    def raw
+      @markup
+    end
+
+    def markup_context(markup)
+      "in \"{{#{markup}}}\""
+    end
+
+    def lax_parse(markup)
       @filters = []
-      if match = markup.match(/\s*(#{QuotedFragment})(.*)/)
+      return unless markup =~ MarkupWithQuotedFragment
-        @name = match[1]
+
-        if match[2].match(/#{FilterSeparator}\s*(.*)/)
+      name_markup = $1
-          filters = Regexp.last_match(1).scan(FilterParser)
+      filter_markup = $2
+      @name = Expression.parse(name_markup)
+      if filter_markup =~ FilterMarkupRegex
+        filters = $1.scan(FilterParser)
         filters.each do |f|
-            if matches = f.match(/\s*(\w+)/)
+          next unless f =~ /\w+/
-              filtername = matches[1]
+          filtername = Regexp.last_match(0)
-              filterargs = f.scan(/(?:#{FilterArgumentSeparator}|#{ArgumentSeparator})\s*(#{QuotedFragment})/).flatten
+          filterargs = f.scan(FilterArgsRegex).flatten
-              @filters << [filtername.to_sym, filterargs]
+          @filters << parse_filter_expressions(filtername, filterargs)
         end
       end
     end
+
+    def strict_parse(markup)
+      @filters = []
+      p = Parser.new(markup)
+
+      @name = Expression.parse(p.expression)
+      while p.consume?(:pipe)
+        filtername = p.consume(:id)
+        filterargs = p.consume?(:colon) ? parse_filterargs(p) : []
+        @filters << parse_filter_expressions(filtername, filterargs)
       end
+      p.consume(:end_of_string)
+    end
+
+    def parse_filterargs(p)
+      # first argument
+      filterargs = [p.argument]
+      # followed by comma separated others
+      filterargs << p.argument while p.consume?(:comma)
+      filterargs
     end
 
     def render(context)
-      return '' if @name.nil?
+      obj = @filters.inject(context.evaluate(@name)) do |output, (filter_name, filter_args, filter_kwargs)|
-      @filters.inject(context[@name]) do |output, filter|
+        filter_args = evaluate_filter_expressions(context, filter_args, filter_kwargs)
-        filterargs = filter[1].to_a.collect do |a|
+        context.invoke(filter_name, output, *filter_args)
-         context[a]
-        end
-        begin
-          output = context.invoke(filter[0], output, *filterargs)
-        rescue FilterNotFound
-          raise FilterNotFound, "Error - filter '#{filter[0]}' in '#{@markup.strip}' could not be found."
       end
+
+      obj = context.apply_global_filter(obj)
+
+      taint_check(context, obj)
+
+      obj
+    end
+
+    private
+
+    def parse_filter_expressions(filter_name, unparsed_args)
+      filter_args = []
+      keyword_args = nil
+      unparsed_args.each do |a|
+        if matches = a.match(JustTagAttributes)
+          keyword_args ||= {}
+          keyword_args[matches[1]] = Expression.parse(matches[2])
+        else
+          filter_args << Expression.parse(a)
+        end
+      end
+      result = [filter_name, filter_args]
+      result << keyword_args if keyword_args
+      result
+    end
+
+    def evaluate_filter_expressions(context, filter_args, filter_kwargs)
+      parsed_args = filter_args.map{ |expr| context.evaluate(expr) }
+      if filter_kwargs
+        parsed_kwargs = {}
+        filter_kwargs.each do |key, expr|
+          parsed_kwargs[key] = context.evaluate(expr)
+        end
+        parsed_args << parsed_kwargs
+      end
+      parsed_args
+    end
+
+    def taint_check(context, obj)
+      return unless obj.tainted?
+      return if Template.taint_mode == :lax
+
+      @markup =~ QuotedFragment
+      name = Regexp.last_match(0)
+
+      error = TaintedError.new("variable '#{name}' is tainted and was not escaped")
+      error.line_number = line_number
+      error.template_name = context.template_name
+
+      case Template.taint_mode
+      when :warn
+        context.warnings << error
+      when :error
+        raise error
+      end
+    end
+
+    class ParseTreeVisitor < Liquid::ParseTreeVisitor
+      def children
+        [@node.name] + @node.filters.flatten
       end
     end
   end

lib/liquid/variable_lookup.rb

@@ -0,0 +1,88 @@
+module Liquid
+  class VariableLookup
+    SQUARE_BRACKETED = /\A\[(.*)\]\z/m
+    COMMAND_METHODS = ['size'.freeze, 'first'.freeze, 'last'.freeze].freeze
+
+    attr_reader :name, :lookups
+
+    def self.parse(markup)
+      new(markup)
+    end
+
+    def initialize(markup)
+      lookups = markup.scan(VariableParser)
+
+      name = lookups.shift
+      if name =~ SQUARE_BRACKETED
+        name = Expression.parse($1)
+      end
+      @name = name
+
+      @lookups = lookups
+      @command_flags = 0
+
+      @lookups.each_index do |i|
+        lookup = lookups[i]
+        if lookup =~ SQUARE_BRACKETED
+          lookups[i] = Expression.parse($1)
+        elsif COMMAND_METHODS.include?(lookup)
+          @command_flags |= 1 << i
+        end
+      end
+    end
+
+    def evaluate(context)
+      name = context.evaluate(@name)
+      object = context.find_variable(name)
+
+      @lookups.each_index do |i|
+        key = context.evaluate(@lookups[i])
+
+        # If object is a hash- or array-like object we look for the
+        # presence of the key and if its available we return it
+        if object.respond_to?(:[]) &&
+            ((object.respond_to?(:key?) && object.key?(key)) ||
+             (object.respond_to?(:fetch) && key.is_a?(Integer)))
+
+          # if its a proc we will replace the entry with the proc
+          res = context.lookup_and_evaluate(object, key)
+          object = res.to_liquid
+
+          # Some special cases. If the part wasn't in square brackets and
+          # no key with the same name was found we interpret following calls
+          # as commands and call them on the current object
+        elsif @command_flags & (1 << i) != 0 && object.respond_to?(key)
+          object = object.send(key).to_liquid
+
+          # No key was present with the desired value and it wasn't one of the directly supported
+          # keywords either. The only thing we got left is to return nil or
+          # raise an exception if `strict_variables` option is set to true
+        else
+          return nil unless context.strict_variables
+          raise Liquid::UndefinedVariable, "undefined variable #{key}"
+        end
+
+        # If we are dealing with a drop here we have to
+        object.context = context if object.respond_to?(:context=)
+      end
+
+      object
+    end
+
+    def ==(other)
+      self.class == other.class && state == other.state
+    end
+
+    protected
+
+    def state
+      [@name, @lookups, @command_flags]
+    end
+
+    class ParseTreeVisitor < Liquid::ParseTreeVisitor
+      def children
+        @node.lookups
+      end
+    end
+  end
+end

lib/liquid/version.rb

@@ -0,0 +1,5 @@
+# encoding: utf-8
+
+module Liquid
+  VERSION = "4.0.3".freeze
+end

liquid.gemspec

@@ -1,23 +1,31 @@
-# -*- encoding: utf-8 -*-
+# encoding: utf-8
+
+lib = File.expand_path('../lib/', __FILE__)
+$LOAD_PATH.unshift lib unless $LOAD_PATH.include?(lib)
+
+require "liquid/version"
 
 Gem::Specification.new do |s|
-  s.platform    = Gem::Platform::RUBY
-
   s.name        = "liquid"
-  s.version     = '2.2.2'
+  s.version     = Liquid::VERSION
+  s.platform    = Gem::Platform::RUBY
   s.summary     = "A secure, non-evaling end user template engine with aesthetic markup."
-
+  s.authors     = ["Tobias Lütke"]
-  s.authors     = ["Tobias Luetke"]
   s.email       = ["tobi@leetsoft.com"]
   s.homepage    = "http://www.liquidmarkup.org"
+  s.license     = "MIT"
+  # s.description = "A secure, non-evaling end user template engine with aesthetic markup."
 
-  s.description = "A secure, non-evaling end user template engine with aesthetic markup."
+  s.required_ruby_version     = ">= 2.1.0"
-
   s.required_rubygems_version = ">= 1.3.7"
 
-  s.files             = Dir.glob("{lib}/**/*") + %w(MIT-LICENSE README.md)
+  s.test_files  = Dir.glob("{test}/**/*")
+  s.files       = Dir.glob("{lib}/**/*") + %w(LICENSE README.md)
 
-  s.extra_rdoc_files  = ["History.txt", "Manifest.txt", "README.md"]
+  s.extra_rdoc_files = ["History.md", "README.md"]
 
-  s.require_path = 'lib'
+  s.require_path = "lib"
+
+  s.add_development_dependency 'rake', '~> 11.3'
+  s.add_development_dependency 'minitest'
 end

performance/benchmark.rb

@@ -0,0 +1,18 @@
+require 'benchmark/ips'
+require_relative 'theme_runner'
+
+Liquid::Template.error_mode = ARGV.first.to_sym if ARGV.first
+profiler = ThemeRunner.new
+
+Benchmark.ips do |x|
+  x.time = 10
+  x.warmup = 5
+
+  puts
+  puts "Running benchmark for #{x.time} seconds (with #{x.warmup} seconds warmup)."
+  puts
+
+  x.report("parse:") { profiler.compile }
+  x.report("render:") { profiler.render }
+  x.report("parse & render:") { profiler.run }
+end

performance/memory_profile.rb

@@ -0,0 +1,26 @@
+# frozen_string_literal: true
+
+require 'benchmark/ips'
+require 'memory_profiler'
+require_relative 'theme_runner'
+
+def profile(phase, &block)
+  puts
+  puts "#{phase}:"
+  puts
+
+  report = MemoryProfiler.report(&block)
+
+  report.pretty_print(
+    color_output: true,
+    scale_bytes: true,
+    detailed_report: true
+  )
+end
+
+Liquid::Template.error_mode = ARGV.first.to_sym if ARGV.first
+
+profiler = ThemeRunner.new
+
+profile("Parsing") { profiler.compile }
+profile("Rendering") { profiler.render }

performance/profile.rb

@@ -0,0 +1,24 @@
+require 'stackprof'
+require_relative 'theme_runner'
+
+Liquid::Template.error_mode = ARGV.first.to_sym if ARGV.first
+profiler = ThemeRunner.new
+profiler.run
+
+[:cpu, :object].each do |profile_type|
+  puts "Profiling in #{profile_type} mode..."
+  results = StackProf.run(mode: profile_type) do
+    200.times do
+      profiler.run
+    end
+  end
+
+  if profile_type == :cpu && graph_filename = ENV['GRAPH_FILENAME']
+    File.open(graph_filename, 'w') do |f|
+      StackProf::Report.new(results).print_graphviz(nil, f)
+    end
+  end
+
+  StackProf::Report.new(results).print_text(false, 20)
+  File.write(ENV['FILENAME'] + "." + profile_type.to_s, Marshal.dump(results)) if ENV['FILENAME']
+end

performance/shopify.rb

@@ -1,92 +0,0 @@
-# This profiler run simulates Shopify.
-# We are looking in the tests directory for liquid files and render them within the designated layout file.
-# We will also export a substantial database to liquid which the templates can render values of. 
-# All this is to make the benchmark as non syntetic as possible. All templates and tests are lifted from
-# direct real-world usage and the profiler measures code that looks very similar to the way it looks in 
-# Shopify which is likely the biggest user of liquid in the world which something to the tune of several 
-# million Template#render calls a day. 
-
-require 'rubygems'
-require 'active_support'
-require 'yaml'
-require 'digest/md5'
-require File.dirname(__FILE__) + '/shopify/liquid'
-require File.dirname(__FILE__) + '/shopify/database.rb'
-
-require "ruby-prof" rescue fail("install ruby-prof extension/gem")
-
-class ThemeProfiler
-  
-  # Load all templates into memory, do this now so that 
-  # we don't profile IO. 
-  def initialize
-    @tests = Dir[File.dirname(__FILE__) + '/tests/**/*.liquid'].collect do |test|
-      next if File.basename(test) == 'theme.liquid'
-      
-      theme_path = File.dirname(test) + '/theme.liquid'
-      
-      [File.read(test), (File.file?(theme_path) ? File.read(theme_path) : nil), test]
-    end.compact
-  end  
-  
-  
-  def profile
-    RubyProf.measure_mode = RubyProf::WALL_TIME
-    
-    # Dup assigns because will make some changes to them
-    assigns = Database.tables.dup
-    
-    @tests.each do |liquid, layout, template_name|
-      
-      # Compute page_tempalte outside of profiler run, uninteresting to profiler
-      html = nil
-      page_template = File.basename(template_name, File.extname(template_name))
-      
-      # Profile compiling and rendering both
-      RubyProf.resume { html = compile_and_render(liquid, layout, assigns, page_template) }
-      
-      # return the result and the MD5 of the content, this can be used to detect regressions between liquid version
-      $stdout.puts "* rendered template %s, content: %s" % [template_name, Digest::MD5.hexdigest(html)]
-      
-      # Uncomment to dump html files to /tmp so that you can inspect for errors
-      # File.open("/tmp/#{File.basename(template_name)}.html", "w+") { |fp| fp <<html}
-    end
-  
-    RubyProf.stop    
-  end
-  
-  def compile_and_render(template, layout, assigns, page_template)    
-    tmpl = Liquid::Template.new
-    tmpl.assigns['page_title'] = 'Page title'
-    tmpl.assigns['template'] = page_template
-    
-    content_for_layout = tmpl.parse(template).render(assigns)
-    
-    if layout
-      assigns['content_for_layout'] = content_for_layout      
-      tmpl.parse(layout).render(assigns)
-    else
-      content_for_layout
-    end    
-  end
-end
-
-
-  profiler = ThemeProfiler.new
-
-  puts 'Running profiler...'
-
-  results  = profiler.profile
-  
-  puts 'Success'
-  puts
-
-[RubyProf::FlatPrinter, RubyProf::GraphPrinter, RubyProf::GraphHtmlPrinter, RubyProf::CallTreePrinter].each do |klass|
-  filename = (ENV['TMP'] || '/tmp') + (klass.name.include?('Html') ? "/liquid.#{klass.name.downcase}.html" : "/liquid.#{klass.name.downcase}.txt")
-  filename.gsub!(/:+/, '_')
-  File.open(filename, "w+") { |fp| klass.new(results).print(fp) }
-  $stderr.puts "wrote #{klass.name} output to #{filename}"
-end
-
-
-

performance/shopify/comment_form.rb

@@ -1,21 +1,21 @@
 class CommentForm < Liquid::Block
   Syntax = /(#{Liquid::VariableSignature}+)/
 
-  def initialize(tag_name, markup, tokens)
+  def initialize(tag_name, markup, options)
+    super
+
     if markup =~ Syntax
       @variable_name = $1
       @attributes = {}
     else
       raise SyntaxError.new("Syntax Error in 'comment_form' - Valid syntax: comment_form [article]")
     end
-    
-    super
   end
 
   def render(context)
     article = context[@variable_name]
 
-    context.stack do       
+    context.stack('form') do
       context['form'] = {
         'posted_successfully?' => context.registers[:posted_successfully],
         'errors' => context['comment.errors'],
@@ -28,6 +28,6 @@ class CommentForm < Liquid::Block
   end
 
   def wrap_in_form(article, input)
-    %Q{<form id="article-#{article.id}-comment-form" class="comment-form" method="post" action="">\n#{input}\n</form>}    
+    %(<form id="article-#{article.id}-comment-form" class="comment-form" method="post" action="">\n#{input}\n</form>)
   end
 end

performance/shopify/database.rb

@@ -1,11 +1,11 @@
 require 'yaml'
-module Database
 
+module Database
   # Load the standard vision toolkit database and re-arrage it to be simply exportable
   # to liquid as assigns. All this is based on Shopify
   def self.tables
     @tables ||= begin
-      db = YAML.load_file(File.dirname(__FILE__) + '/vision.database.yml')
+      db = YAML.load_file("#{__dir__}/vision.database.yml")
 
       # From vision source
       db['products'].each do |product|
@@ -39,7 +39,7 @@ module Database
   end
 end
 
-if __FILE__ == $0
+if __FILE__ == $PROGRAM_NAME
   p Database.tables['collections']['frontpage'].keys
   # p Database.tables['blog']['articles']
 end

performance/shopify/json_filter.rb

@@ -1,7 +1,7 @@
+require 'json'
+
 module JsonFilter
-  
   def json(object)
-    object.reject {|k,v| k == "collections" }.to_json
+    JSON.dump(object.reject { |k, v| k == "collections" })
   end
-  
 end

performance/shopify/liquid.rb

@@ -1,12 +1,13 @@
-require File.dirname(__FILE__) + '/../../lib/liquid'
+$:.unshift __dir__ + '/../../lib'
+require_relative '../../lib/liquid'
 
-require File.dirname(__FILE__) + '/comment_form'
+require_relative 'comment_form'
-require File.dirname(__FILE__) + '/paginate'
+require_relative 'paginate'
-require File.dirname(__FILE__) + '/json_filter'
+require_relative 'json_filter'
-require File.dirname(__FILE__) + '/money_filter'
+require_relative 'money_filter'
-require File.dirname(__FILE__) + '/shop_filter'
+require_relative 'shop_filter'
-require File.dirname(__FILE__) + '/tag_filter'
+require_relative 'tag_filter'
-require File.dirname(__FILE__) + '/weight_filter'
+require_relative 'weight_filter'
 
 Liquid::Template.register_tag 'paginate', Paginate
 Liquid::Template.register_tag 'form', CommentForm

performance/shopify/money_filter.rb

@@ -1,5 +1,4 @@
 module MoneyFilter
-  
   def money_with_currency(money)
     return '' if money.nil?
     sprintf("$ %.2f USD", money / 100.0)

performance/shopify/paginate.rb

@@ -1,8 +1,8 @@
 class Paginate < Liquid::Block
   Syntax     = /(#{Liquid::QuotedFragment})\s*(by\s*(\d+))?/
 
-  def initialize(tag_name, markup, tokens)
+  def initialize(tag_name, markup, options)
-    @nodelist = []
+    super
 
     if markup =~ Syntax
       @collection_name = $1
@@ -19,14 +19,12 @@ class Paginate < Liquid::Block
     else
       raise SyntaxError.new("Syntax Error in tag 'paginate' - Valid syntax: paginate [collection] by number")
     end
-  
-    super
   end
 
   def render(context)
     @context = context
 
-    context.stack do                      
+    context.stack('paginate') do
       current_page  = context['current_page'].to_i
 
       pagination = {
@@ -53,14 +51,13 @@ class Paginate < Liquid::Block
 
       if page_count > 2
         1.upto(page_count - 1) do |page|
-        
           if current_page == page
             pagination['parts'] << no_link(page)
           elsif page == 1
             pagination['parts'] << link(page, page)
           elsif page == page_count - 1
             pagination['parts'] << link(page, page)
-          elsif page <= current_page - @attributes['window_size'] or page >= current_page + @attributes['window_size']
+          elsif page <= current_page - @attributes['window_size'] || page >= current_page + @attributes['window_size']
             next if hellip_break
             pagination['parts'] << no_link('&hellip;')
             hellip_break = true
@@ -73,7 +70,7 @@ class Paginate < Liquid::Block
         end
       end
 
-      render_all(@nodelist, context)      
+      super
     end
   end
 

performance/shopify/shop_filter.rb

@@ -1,5 +1,4 @@
 module ShopFilter
-      
   def asset_url(input)
     "/files/1/[shop_id]/[shop_id]/assets/#{input}"
   end
@@ -21,11 +20,11 @@ module ShopFilter
   end
 
   def link_to(link, url, title = "")
-    %|<a href="#{url}" title="#{title}">#{link}</a>|
+    %(<a href="#{url}" title="#{title}">#{link}</a>)
   end
 
   def img_tag(url, alt = "")
-    %|<img src="#{url}" alt="#{alt}" />|  
+    %(<img src="#{url}" alt="#{alt}" />)
   end
 
   def link_to_vendor(vendor)
@@ -45,16 +44,15 @@ module ShopFilter
   end
 
   def url_for_vendor(vendor_title)
-    "/collections/#{vendor_title.to_handle}"
+    "/collections/#{to_handle(vendor_title)}"
   end
 
   def url_for_type(type_title)
-    "/collections/#{type_title.to_handle}"
+    "/collections/#{to_handle(type_title)}"
   end
 
   def product_img_url(url, style = 'small')
-    
+    unless url =~ /\Aproducts\/([\w\-\_]+)\.(\w{2,4})/
-    unless url =~ /^products\/([\w\-\_]+)\.(\w{2,4})/
       raise ArgumentError, 'filter "size" can only be called on product images'
     end
 
@@ -69,7 +67,6 @@ module ShopFilter
   end
 
   def default_pagination(paginate)
-    
     html = []
     html << %(<span class="prev">#{link_to(paginate['previous']['title'], paginate['previous']['url'])}</span>) if paginate['previous']
 
@@ -95,4 +92,15 @@ module ShopFilter
     input == 1 ? singular : plural
   end
 
+  private
+
+  def to_handle(str)
+    result = str.dup
+    result.downcase!
+    result.delete!("'\"()[]")
+    result.gsub!(/\W+/, '-')
+    result.gsub!(/-+\z/, '') if result[-1] == '-'
+    result.gsub!(/\A-+/, '') if result[0] == '-'
+    result
+  end
 end

performance/shopify/tag_filter.rb

@@ -1,5 +1,4 @@
 module TagFilter
-    
   def link_to_tag(label, tag)
     "<a title=\"Show tag #{tag}\" href=\"/collections/#{@context['handle']}/#{tag}\">#{label}</a>"
   end
@@ -21,5 +20,4 @@ module TagFilter
     tags = (@context['current_tags'] - [tag]).uniq
     "<a title=\"Show tag #{tag}\" href=\"/collections/#{@context['handle']}/#{tags.join("+")}\">#{label}</a>"
   end
-  
 end

performance/shopify/weight_filter.rb

@@ -1,5 +1,4 @@
 module WeightFilter
-
   def weight(grams)
     sprintf("%.2f", grams / 1000)
   end
@@ -7,5 +6,4 @@ module WeightFilter
   def weight_with_unit(grams)
     "#{weight(grams)} kg"
   end
-  
 end

performance/tests/dropify/index.liquid

@@ -28,7 +28,7 @@
   {% else %}
     <div class="article-body textile">
     In <em>Admin &gt; Blogs &amp; Pages</em>, create a page with the handle <strong><code>frontpage</code></strong> and it will show up here.<br />
-	  {{ "Learn more about handles" | link_to "http://wiki.shopify.com/Handle" }}
+    {{ "Learn more about handles" | link_to: "http://wiki.shopify.com/Handle" }}
     </div>
   {% endif %}
 

performance/tests/ripen/index.liquid

@@ -26,7 +26,7 @@
       {{ article.content }}
     {% else %}
       In <em>Admin &gt; Blogs &amp; Pages</em>, create a page with the handle <strong><code>frontpage</code></strong> and it will show up here.<br />
-  	  {{ "Learn more about handles" | link_to "http://wiki.shopify.com/Handle" }}
+      {{ "Learn more about handles" | link_to: "http://wiki.shopify.com/Handle" }}
     {% endif %}
   </div>
 </div>

performance/tests/vogue/index.liquid

@@ -5,7 +5,7 @@
       {{ article.content }}
     {% else %}
       In <em>Admin &gt; Blogs &amp; Pages</em>, create a page with the handle <strong><code>frontpage</code></strong> and it will show up here.<br />
-  	  {{ "Learn more about handles" | link_to "http://wiki.shopify.com/Handle" }}
+      {{ "Learn more about handles" | link_to: "http://wiki.shopify.com/Handle" }}
     {% endif %}
   </div>
 

performance/theme_runner.rb

@@ -0,0 +1,120 @@
+# This profiler run simulates Shopify.
+# We are looking in the tests directory for liquid files and render them within the designated layout file.
+# We will also export a substantial database to liquid which the templates can render values of.
+# All this is to make the benchmark as non syntetic as possible. All templates and tests are lifted from
+# direct real-world usage and the profiler measures code that looks very similar to the way it looks in
+# Shopify which is likely the biggest user of liquid in the world which something to the tune of several
+# million Template#render calls a day.
+
+require_relative 'shopify/liquid'
+require_relative 'shopify/database'
+
+class ThemeRunner
+  class FileSystem
+    def initialize(path)
+      @path = path
+    end
+
+    # Called by Liquid to retrieve a template file
+    def read_template_file(template_path)
+      File.read(@path + '/' + template_path + '.liquid')
+    end
+  end
+
+  # Initialize a new liquid ThemeRunner instance
+  # Will load all templates into memory, do this now so that we don't profile IO.
+  def initialize
+    @tests = Dir[__dir__ + '/tests/**/*.liquid'].collect do |test|
+      next if File.basename(test) == 'theme.liquid'
+
+      theme_path = File.dirname(test) + '/theme.liquid'
+      {
+        liquid: File.read(test),
+        layout: (File.file?(theme_path) ? File.read(theme_path) : nil),
+        template_name: test
+      }
+    end.compact
+
+    compile_all_tests
+  end
+
+  # `compile` will test just the compilation portion of liquid without any templates
+  def compile
+    @tests.each do |test_hash|
+      Liquid::Template.new.parse(test_hash[:liquid])
+      Liquid::Template.new.parse(test_hash[:layout])
+    end
+  end
+
+  # `run` is called to benchmark rendering and compiling at the same time
+  def run
+    each_test do |liquid, layout, assigns, page_template, template_name|
+      compile_and_render(liquid, layout, assigns, page_template, template_name)
+    end
+  end
+
+  # `render` is called to benchmark just the render portion of liquid
+  def render
+    @compiled_tests.each do |test|
+      tmpl = test[:tmpl]
+      assigns = test[:assigns]
+      layout = test[:layout]
+
+      if layout
+        assigns['content_for_layout'] = tmpl.render!(assigns)
+        layout.render!(assigns)
+      else
+        tmpl.render!(assigns)
+      end
+    end
+  end
+
+  private
+
+  def compile_and_render(template, layout, assigns, page_template, template_file)
+    compiled_test = compile_test(template, layout, assigns, page_template, template_file)
+    assigns['content_for_layout'] = compiled_test[:tmpl].render!(assigns)
+    compiled_test[:layout].render!(assigns) if layout
+  end
+
+  def compile_all_tests
+    @compiled_tests = []
+    each_test do |liquid, layout, assigns, page_template, template_name|
+      @compiled_tests << compile_test(liquid, layout, assigns, page_template, template_name)
+    end
+    @compiled_tests
+  end
+
+  def compile_test(template, layout, assigns, page_template, template_file)
+    tmpl = init_template(page_template, template_file)
+    parsed_template = tmpl.parse(template).dup
+
+    if layout
+      parsed_layout = tmpl.parse(layout)
+      { tmpl: parsed_template, assigns: assigns, layout: parsed_layout }
+    else
+      { tmpl: parsed_template, assigns: assigns }
+    end
+  end
+
+  # utility method with similar functionality needed in `compile_all_tests` and `run`
+  def each_test
+    # Dup assigns because will make some changes to them
+    assigns = Database.tables.dup
+
+    @tests.each do |test_hash|
+      # Compute page_template outside of profiler run, uninteresting to profiler
+      page_template = File.basename(test_hash[:template_name], File.extname(test_hash[:template_name]))
+      yield(test_hash[:liquid], test_hash[:layout], assigns, page_template, test_hash[:template_name])
+    end
+  end
+
+  # set up a new Liquid::Template object for use in `compile_and_render` and `compile_test`
+  def init_template(page_template, template_file)
+    tmpl = Liquid::Template.new
+    tmpl.assigns['page_title'] = 'Page title'
+    tmpl.assigns['template'] = page_template
+    tmpl.registers[:file_system] = ThemeRunner::FileSystem.new(File.dirname(template_file))
+    tmpl
+  end
+end

test/extra/breakpoint.rb

@@ -1,547 +0,0 @@
-# The Breakpoint library provides the convenience of
-# being able to inspect and modify state, diagnose
-# bugs all via IRB by simply setting breakpoints in
-# your applications by the call of a method.
-#
-# This library was written and is supported by me,
-# Florian Gross. I can be reached at flgr@ccan.de
-# and enjoy getting feedback about my libraries.
-#
-# The whole library (including breakpoint_client.rb
-# and binding_of_caller.rb) is licensed under the
-# same license that Ruby uses. (Which is currently
-# either the GNU General Public License or a custom
-# one that allows for commercial usage.) If you for
-# some good reason need to use this under another
-# license please contact me.
-
-require 'irb'
-require 'caller'
-require 'drb'
-require 'drb/acl'
-require 'thread'
-
-module Breakpoint
-  id = %q$Id: breakpoint.rb 52 2005-02-26 19:43:19Z flgr $
-  current_version = id.split(" ")[2]
-  unless defined?(Version)
-    # The Version of ruby-breakpoint you are using as String of the
-    # 1.2.3 form where the digits stand for release, major and minor
-    # version respectively.
-    Version = "0.5.0"
-  end
-
-  extend self
-
-  # This will pop up an interactive ruby session at a
-  # pre-defined break point in a Ruby application. In
-  # this session you can examine the environment of
-  # the break point.
-  #
-  # You can get a list of variables in the context using
-  # local_variables via +local_variables+. You can then
-  # examine their values by typing their names.
-  #
-  # You can have a look at the call stack via +caller+.
-  #
-  # The source code around the location where the breakpoint
-  # was executed can be examined via +source_lines+. Its
-  # argument specifies how much lines of context to display.
-  # The default amount of context is 5 lines. Note that
-  # the call to +source_lines+ can raise an exception when
-  # it isn't able to read in the source code.
-  #
-  # breakpoints can also return a value. They will execute
-  # a supplied block for getting a default return value.
-  # A custom value can be returned from the session by doing
-  # +throw(:debug_return, value)+.
-  #
-  # You can also give names to break points which will be
-  # used in the message that is displayed upon execution 
-  # of them.
-  #
-  # Here's a sample of how breakpoints should be placed:
-  #
-  #   class Person
-  #     def initialize(name, age)
-  #       @name, @age = name, age
-  #       breakpoint("Person#initialize")
-  #     end
-  #
-  #     attr_reader :age
-  #     def name
-  #       breakpoint("Person#name") { @name }
-  #     end
-  #   end
-  #
-  #   person = Person.new("Random Person", 23)
-  #   puts "Name: #{person.name}"
-  #
-  # And here is a sample debug session:
-  #
-  #   Executing break point "Person#initialize" at file.rb:4 in `initialize'
-  #   irb(#<Person:0x292fbe8>):001:0> local_variables
-  #   => ["name", "age", "_", "__"]
-  #   irb(#<Person:0x292fbe8>):002:0> [name, age]
-  #   => ["Random Person", 23]
-  #   irb(#<Person:0x292fbe8>):003:0> [@name, @age]
-  #   => ["Random Person", 23]
-  #   irb(#<Person:0x292fbe8>):004:0> self
-  #   => #<Person:0x292fbe8 @age=23, @name="Random Person">
-  #   irb(#<Person:0x292fbe8>):005:0> @age += 1; self
-  #   => #<Person:0x292fbe8 @age=24, @name="Random Person">
-  #   irb(#<Person:0x292fbe8>):006:0> exit
-  #   Executing break point "Person#name" at file.rb:9 in `name'
-  #   irb(#<Person:0x292fbe8>):001:0> throw(:debug_return, "Overriden name")
-  #   Name: Overriden name
-  #
-  # Breakpoint sessions will automatically have a few
-  # convenience methods available. See Breakpoint::CommandBundle
-  # for a list of them.
-  #
-  # Breakpoints can also be used remotely over sockets.
-  # This is implemented by running part of the IRB session
-  # in the application and part of it in a special client.
-  # You have to call Breakpoint.activate_drb to enable
-  # support for remote breakpoints and then run
-  # breakpoint_client.rb which is distributed with this
-  # library. See the documentation of Breakpoint.activate_drb
-  # for details.
-  def breakpoint(id = nil, context = nil, &block)
-    callstack = caller
-    callstack.slice!(0, 3) if callstack.first["breakpoint"]
-    file, line, method = *callstack.first.match(/^(.+?):(\d+)(?::in `(.*?)')?/).captures
-
-    message = "Executing break point " + (id ? "#{id.inspect} " : "") +
-              "at #{file}:#{line}" + (method ? " in `#{method}'" : "")
-
-    if context then
-      return handle_breakpoint(context, message, file, line, &block)
-    end
-
-    Binding.of_caller do |binding_context|
-      handle_breakpoint(binding_context, message, file, line, &block)
-    end
-  end
-
-  # These commands are automatically available in all breakpoint shells.
-  module CommandBundle
-    # Proxy to a Breakpoint client. Lets you directly execute code
-    # in the context of the client.
-    class Client
-      def initialize(eval_handler) # :nodoc:
-        eval_handler.untaint
-        @eval_handler = eval_handler
-      end
-
-      instance_methods.each do |method|
-        next if method[/^__.+__$/]
-        undef_method method
-      end
-
-      # Executes the specified code at the client.
-      def eval(code)
-        @eval_handler.call(code)
-      end
-
-      # Will execute the specified statement at the client.
-      def method_missing(method, *args, &block)
-        if args.empty? and not block
-          result = eval "#{method}"
-        else
-          # This is a bit ugly. The alternative would be using an
-          # eval context instead of an eval handler for executing
-          # the code at the client. The problem with that approach
-          # is that we would have to handle special expressions
-          # like "self", "nil" or constants ourself which is hard.
-          remote = eval %{
-            result = lambda { |block, *args| #{method}(*args, &block) }
-            def result.call_with_block(*args, &block)
-              call(block, *args)
-            end
-            result
-          }
-          remote.call_with_block(*args, &block)
-        end
-
-        return result
-      end
-    end
-
-    # Returns the source code surrounding the location where the
-    # breakpoint was issued.
-    def source_lines(context = 5, return_line_numbers = false)
-      lines = File.readlines(@__bp_file).map { |line| line.chomp }
-
-      break_line = @__bp_line
-      start_line = [break_line - context, 1].max
-      end_line = break_line + context
-
-      result = lines[(start_line - 1) .. (end_line - 1)]
-
-      if return_line_numbers then
-        return [start_line, break_line, result]
-      else
-        return result
-      end
-    end
-
-    # Lets an object that will forward method calls to the breakpoint
-    # client. This is useful for outputting longer things at the client
-    # and so on. You can for example do these things:
-    #
-    #   client.puts "Hello" # outputs "Hello" at client console
-    #   # outputs "Hello" into the file temp.txt at the client
-    #   client.File.open("temp.txt", "w") { |f| f.puts "Hello" } 
-    def client()
-      if Breakpoint.use_drb? then
-        sleep(0.5) until Breakpoint.drb_service.eval_handler
-        Client.new(Breakpoint.drb_service.eval_handler)
-      else
-        Client.new(lambda { |code| eval(code, TOPLEVEL_BINDING) })
-      end
-    end
-  end
-
-  def handle_breakpoint(context, message, file = "", line = "", &block) # :nodoc:
-    catch(:debug_return) do |value|
-      eval(%{
-        @__bp_file = #{file.inspect}
-        @__bp_line = #{line}
-        extend Breakpoint::CommandBundle
-        extend DRbUndumped if self
-      }, context) rescue nil
-
-      if not use_drb? then
-        puts message
-        IRB.start(nil, IRB::WorkSpace.new(context))
-      else
-        @drb_service.add_breakpoint(context, message)
-      end
-
-      block.call if block
-    end
-  end
-
-  # These exceptions will be raised on failed asserts
-  # if Breakpoint.asserts_cause_exceptions is set to
-  # true.
-  class FailedAssertError < RuntimeError
-  end
-
-  # This asserts that the block evaluates to true.
-  # If it doesn't evaluate to true a breakpoint will
-  # automatically be created at that execution point.
-  #
-  # You can disable assert checking in production
-  # code by setting Breakpoint.optimize_asserts to
-  # true. (It will still be enabled when Ruby is run
-  # via the -d argument.)
-  #
-  # Example:
-  #   person_name = "Foobar"
-  #   assert { not person_name.nil? }
-  #
-  # Note: If you want to use this method from an
-  # unit test, you will have to call it by its full
-  # name, Breakpoint.assert.
-  def assert(context = nil, &condition)
-    return if Breakpoint.optimize_asserts and not $DEBUG
-    return if yield
-
-    callstack = caller
-    callstack.slice!(0, 3) if callstack.first["assert"]
-    file, line, method = *callstack.first.match(/^(.+?):(\d+)(?::in `(.*?)')?/).captures
-
-    message = "Assert failed at #{file}:#{line}#{" in `#{method}'" if method}."
-
-    if Breakpoint.asserts_cause_exceptions and not $DEBUG then
-      raise(Breakpoint::FailedAssertError, message)
-    end
-
-    message += " Executing implicit breakpoint."
-
-    if context then
-      return handle_breakpoint(context, message, file, line)
-    end
-
-    Binding.of_caller do |context|
-      handle_breakpoint(context, message, file, line)
-    end
-  end
-
-  # Whether asserts should be ignored if not in debug mode.
-  # Debug mode can be enabled by running ruby with the -d
-  # switch or by setting $DEBUG to true.
-  attr_accessor :optimize_asserts
-  self.optimize_asserts = false
-
-  # Whether an Exception should be raised on failed asserts
-  # in non-$DEBUG code or not. By default this is disabled.
-  attr_accessor :asserts_cause_exceptions
-  self.asserts_cause_exceptions = false
-  @use_drb = false
-
-  attr_reader :drb_service # :nodoc:
-
-  class DRbService # :nodoc:
-    include DRbUndumped
-
-    def initialize
-      @handler = @eval_handler = @collision_handler = nil
-
-      IRB.instance_eval { @CONF[:RC] = true }
-      IRB.run_config
-    end
-
-    def collision
-      sleep(0.5) until @collision_handler
-
-      @collision_handler.untaint
-
-      @collision_handler.call
-    end
-
-    def ping() end
-
-    def add_breakpoint(context, message)
-      workspace = IRB::WorkSpace.new(context)
-      workspace.extend(DRbUndumped)
-
-      sleep(0.5) until @handler
-
-      @handler.untaint
-      @handler.call(workspace, message)
-    rescue Errno::ECONNREFUSED, DRb::DRbConnError
-      raise if Breakpoint.use_drb? 
-    end
-
-    attr_accessor :handler, :eval_handler, :collision_handler
-  end
-
-  # Will run Breakpoint in DRb mode. This will spawn a server
-  # that can be attached to via the breakpoint-client command
-  # whenever a breakpoint is executed. This is useful when you
-  # are debugging CGI applications or other applications where
-  # you can't access debug sessions via the standard input and
-  # output of your application.
-  #
-  # You can specify an URI where the DRb server will run at.
-  # This way you can specify the port the server runs on. The
-  # default URI is druby://localhost:42531.
-  #
-  # Please note that breakpoints will be skipped silently in
-  # case the DRb server can not spawned. (This can happen if
-  # the port is already used by another instance of your
-  # application on CGI or another application.)
-  #
-  # Also note that by default this will only allow access
-  # from localhost. You can however specify a list of
-  # allowed hosts or nil (to allow access from everywhere).
-  # But that will still not protect you from somebody
-  # reading the data as it goes through the net.
-  #
-  # A good approach for getting security and remote access
-  # is setting up an SSH tunnel between the DRb service
-  # and the client. This is usually done like this:
-  #
-  # $ ssh -L20000:127.0.0.1:20000 -R10000:127.0.0.1:10000 example.com
-  # (This will connect port 20000 at the client side to port
-  # 20000 at the server side, and port 10000 at the server
-  # side to port 10000 at the client side.)
-  #
-  # After that do this on the server side: (the code being debugged)
-  # Breakpoint.activate_drb("druby://127.0.0.1:20000", "localhost")
-  #
-  # And at the client side:
-  # ruby breakpoint_client.rb -c druby://127.0.0.1:10000 -s druby://127.0.0.1:20000
-  #
-  # Running through such a SSH proxy will also let you use 
-  # breakpoint.rb in case you are behind a firewall.
-  #
-  # Detailed information about running DRb through firewalls is
-  # available at http://www.rubygarden.org/ruby?DrbTutorial
-  #
-  # == Security considerations
-  # Usually you will be fine when using the default druby:// URI and the default
-  # access control list. However, if you are sitting on a machine where there are
-  # local users that you likely can not trust (this is the case for example on
-  # most web hosts which have multiple users sitting on the same physical machine)
-  # you will be better off by doing client/server communication through a unix
-  # socket. This can be accomplished by calling with a drbunix:/ style URI, e.g.
-  # <code>Breakpoint.activate_drb('drbunix:/tmp/breakpoint_server')</code>. This
-  # will only work on Unix based platforms.
-  def activate_drb(uri = nil, allowed_hosts = ['localhost', '127.0.0.1', '::1'],
-    ignore_collisions = false)
-
-    return false if @use_drb
-
-    uri ||= 'druby://localhost:42531'
-
-    if allowed_hosts then
-      acl = ["deny", "all"]
-
-      Array(allowed_hosts).each do |host|
-        acl += ["allow", host]
-      end
-
-      DRb.install_acl(ACL.new(acl))
-    end
-
-    @use_drb = true
-    @drb_service = DRbService.new
-    did_collision = false
-    begin
-      @service = DRb.start_service(uri, @drb_service)
-    rescue Errno::EADDRINUSE
-      if ignore_collisions then
-        nil
-      else
-        # The port is already occupied by another
-        # Breakpoint service. We will try to tell
-        # the old service that we want its port.
-        # It will then forward that request to the
-        # user and retry.
-        unless did_collision then
-          DRbObject.new(nil, uri).collision
-          did_collision = true
-        end
-        sleep(10)
-        retry
-      end
-    end
-
-    return true
-  end
-
-  # Deactivates a running Breakpoint service.
-  def deactivate_drb
-    Thread.exclusive do
-      @service.stop_service unless @service.nil?
-      @service = nil
-      @use_drb = false
-      @drb_service = nil
-    end
-  end
-
-  # Returns true when Breakpoints are used over DRb.
-  # Breakpoint.activate_drb causes this to be true.
-  def use_drb?
-    @use_drb == true
-  end
-end
-
-module IRB # :nodoc:
-  class << self; remove_method :start; end
-  def self.start(ap_path = nil, main_context = nil, workspace = nil)
-    $0 = File::basename(ap_path, ".rb") if ap_path
-
-    # suppress some warnings about redefined constants
-    old_verbose, $VERBOSE = $VERBOSE, nil
-    IRB.setup(ap_path)
-    $VERBOSE = old_verbose
-
-    if @CONF[:SCRIPT] then
-      irb = Irb.new(main_context, @CONF[:SCRIPT])
-    else
-      irb = Irb.new(main_context)
-    end
-
-    if workspace then
-      irb.context.workspace = workspace
-    end
-
-    @CONF[:IRB_RC].call(irb.context) if @CONF[:IRB_RC]
-    @CONF[:MAIN_CONTEXT] = irb.context
-
-    old_sigint = trap("SIGINT") do
-      begin
-        irb.signal_handle
-      rescue RubyLex::TerminateLineInput
-        # ignored
-      end
-    end
-    
-    catch(:IRB_EXIT) do
-      irb.eval_input
-    end
-  ensure
-    trap("SIGINT", old_sigint)
-  end
-
-  class << self
-    alias :old_CurrentContext :CurrentContext
-    remove_method :CurrentContext
-    remove_method :parse_opts
-  end
-
-  def IRB.CurrentContext
-    if old_CurrentContext.nil? and Breakpoint.use_drb? then
-      result = Object.new
-      def result.last_value; end
-      return result
-    else
-      old_CurrentContext
-    end
-  end
-  def IRB.parse_opts() end
-
-  class Context # :nodoc:
-    alias :old_evaluate :evaluate
-    def evaluate(line, line_no)
-      if line.chomp == "exit" then
-        exit
-      else
-        old_evaluate(line, line_no)
-      end
-    end
-  end
-
-  class WorkSpace # :nodoc:
-    alias :old_evaluate :evaluate
-
-    def evaluate(*args)
-      if Breakpoint.use_drb? then
-        result = old_evaluate(*args)
-        if args[0] != :no_proxy and
-          not [true, false, nil].include?(result)
-        then
-          result.extend(DRbUndumped) rescue nil
-        end
-        return result
-      else
-        old_evaluate(*args)
-      end
-    end
-  end
-
-  module InputCompletor # :nodoc:
-    def self.eval(code, context, *more)
-      # Big hack, this assumes that InputCompletor
-      # will only call eval() when it wants code
-      # to be executed in the IRB context.
-      IRB.conf[:MAIN_CONTEXT].workspace.evaluate(:no_proxy, code, *more)
-    end
-  end
-end
-
-module DRb # :nodoc:
-  class DRbObject # :nodoc:
-    undef :inspect if method_defined?(:inspect)
-    undef :clone if method_defined?(:clone)
-  end
-end
-
-# See Breakpoint.breakpoint
-def breakpoint(id = nil, &block)
-  Binding.of_caller do |context|
-    Breakpoint.breakpoint(id, context, &block)
-  end
-end
-
-# See Breakpoint.assert
-def assert(&block)
-  Binding.of_caller do |context|
-    Breakpoint.assert(context, &block)
-  end
-end

test/extra/caller.rb

@@ -1,80 +0,0 @@
-class Continuation # :nodoc:
-  def self.create(*args, &block) # :nodoc:
-    cc = nil; result = callcc {|c| cc = c; block.call(cc) if block and args.empty?}
-    result ||= args
-    return *[cc, *result]
-  end
-end
-
-class Binding; end # for RDoc
-# This method returns the binding of the method that called your
-# method. It will raise an Exception when you're not inside a method.
-#
-# It's used like this:
-#   def inc_counter(amount = 1)
-#     Binding.of_caller do |binding|
-#       # Create a lambda that will increase the variable 'counter'
-#       # in the caller of this method when called.
-#       inc = eval("lambda { |arg| counter += arg }", binding)
-#       # We can refer to amount from inside this block safely.
-#       inc.call(amount)
-#     end
-#     # No other statements can go here. Put them inside the block.
-#   end
-#   counter = 0
-#   2.times { inc_counter }
-#   counter # => 2
-#
-# Binding.of_caller must be the last statement in the method.
-# This means that you will have to put everything you want to
-# do after the call to Binding.of_caller into the block of it.
-# This should be no problem however, because Ruby has closures.
-# If you don't do this an Exception will be raised. Because of
-# the way that Binding.of_caller is implemented it has to be
-# done this way.
-def Binding.of_caller(&block)
-  old_critical = Thread.critical
-  Thread.critical = true
-  count = 0
-  cc, result, error, extra_data = Continuation.create(nil, nil)
-  error.call if error
-
-  tracer = lambda do |*args|
-    type, context, extra_data = args[0], args[4], args
-    if type == "return"
-      count += 1
-      # First this method and then calling one will return --
-      # the trace event of the second event gets the context
-      # of the method which called the method that called this
-      # method.
-      if count == 2
-        # It would be nice if we could restore the trace_func
-        # that was set before we swapped in our own one, but
-        # this is impossible without overloading set_trace_func
-        # in current Ruby.
-        set_trace_func(nil)
-        cc.call(eval("binding", context), nil, extra_data)
-      end
-    elsif type == "line" then
-      nil
-    elsif type == "c-return" and extra_data[3] == :set_trace_func then
-      nil
-    else
-      set_trace_func(nil)
-      error_msg = "Binding.of_caller used in non-method context or " +
-        "trailing statements of method using it aren't in the block."
-      cc.call(nil, lambda { raise(ArgumentError, error_msg) }, nil)
-    end
-  end
-
-  unless result
-    set_trace_func(tracer)
-    return nil
-  else
-    Thread.critical = old_critical
-    case block.arity
-      when 1 then yield(result)
-      else yield(result, extra_data)        
-    end
-  end
-end

test/fixtures/en_locale.yml

@@ -0,0 +1,9 @@
+---
+  simple: "less is more"
+  whatever: "something %{something}"
+  errors:
+    i18n:
+      undefined_interpolation: "undefined key %{key}"
+      unknown_translation: "translation '%{name}' wasn't found"
+    syntax:
+      oops: "something wasn't right"

test/integration/assign_test.rb

@@ -0,0 +1,48 @@
+require 'test_helper'
+
+class AssignTest < Minitest::Test
+  include Liquid
+
+  def test_assign_with_hyphen_in_variable_name
+    template_source = <<-END_TEMPLATE
+    {% assign this-thing = 'Print this-thing' %}
+    {{ this-thing }}
+    END_TEMPLATE
+    template = Template.parse(template_source)
+    rendered = template.render!
+    assert_equal "Print this-thing", rendered.strip
+  end
+
+  def test_assigned_variable
+    assert_template_result('.foo.',
+      '{% assign foo = values %}.{{ foo[0] }}.',
+      'values' => %w(foo bar baz))
+
+    assert_template_result('.bar.',
+      '{% assign foo = values %}.{{ foo[1] }}.',
+      'values' => %w(foo bar baz))
+  end
+
+  def test_assign_with_filter
+    assert_template_result('.bar.',
+      '{% assign foo = values | split: "," %}.{{ foo[1] }}.',
+      'values' => "foo,bar,baz")
+  end
+
+  def test_assign_syntax_error
+    assert_match_syntax_error(/assign/,
+      '{% assign foo not values %}.',
+      'values' => "foo,bar,baz")
+  end
+
+  def test_assign_uses_error_mode
+    with_error_mode(:strict) do
+      assert_raises(SyntaxError) do
+        Template.parse("{% assign foo = ('X' | downcase) %}")
+      end
+    end
+    with_error_mode(:lax) do
+      assert Template.parse("{% assign foo = ('X' | downcase) %}")
+    end
+  end
+end # AssignTest

test/integration/blank_test.rb

@@ -0,0 +1,106 @@
+require 'test_helper'
+
+class FoobarTag < Liquid::Tag
+  def render(*args)
+    " "
+  end
+
+  Liquid::Template.register_tag('foobar', FoobarTag)
+end
+
+class BlankTestFileSystem
+  def read_template_file(template_path)
+    template_path
+  end
+end
+
+class BlankTest < Minitest::Test
+  include Liquid
+  N = 10
+
+  def wrap_in_for(body)
+    "{% for i in (1..#{N}) %}#{body}{% endfor %}"
+  end
+
+  def wrap_in_if(body)
+    "{% if true %}#{body}{% endif %}"
+  end
+
+  def wrap(body)
+    wrap_in_for(body) + wrap_in_if(body)
+  end
+
+  def test_new_tags_are_not_blank_by_default
+    assert_template_result(" " * N, wrap_in_for("{% foobar %}"))
+  end
+
+  def test_loops_are_blank
+    assert_template_result("", wrap_in_for(" "))
+  end
+
+  def test_if_else_are_blank
+    assert_template_result("", "{% if true %} {% elsif false %} {% else %} {% endif %}")
+  end
+
+  def test_unless_is_blank
+    assert_template_result("", wrap("{% unless true %} {% endunless %}"))
+  end
+
+  def test_mark_as_blank_only_during_parsing
+    assert_template_result(" " * (N + 1), wrap(" {% if false %} this never happens, but still, this block is not blank {% endif %}"))
+  end
+
+  def test_comments_are_blank
+    assert_template_result("", wrap(" {% comment %} whatever {% endcomment %} "))
+  end
+
+  def test_captures_are_blank
+    assert_template_result("", wrap(" {% capture foo %} whatever {% endcapture %} "))
+  end
+
+  def test_nested_blocks_are_blank_but_only_if_all_children_are
+    assert_template_result("", wrap(wrap(" ")))
+    assert_template_result("\n       but this is not " * (N + 1),
+      wrap('{% if true %} {% comment %} this is blank {% endcomment %} {% endif %}
+      {% if true %} but this is not {% endif %}'))
+  end
+
+  def test_assigns_are_blank
+    assert_template_result("", wrap(' {% assign foo = "bar" %} '))
+  end
+
+  def test_whitespace_is_blank
+    assert_template_result("", wrap(" "))
+    assert_template_result("", wrap("\t"))
+  end
+
+  def test_whitespace_is_not_blank_if_other_stuff_is_present
+    body = "     x "
+    assert_template_result(body * (N + 1), wrap(body))
+  end
+
+  def test_increment_is_not_blank
+    assert_template_result(" 0" * 2 * (N + 1), wrap("{% assign foo = 0 %} {% increment foo %} {% decrement foo %}"))
+  end
+
+  def test_cycle_is_not_blank
+    assert_template_result("  " * ((N + 1) / 2) + " ", wrap("{% cycle ' ', ' ' %}"))
+  end
+
+  def test_raw_is_not_blank
+    assert_template_result("  " * (N + 1), wrap(" {% raw %} {% endraw %}"))
+  end
+
+  def test_include_is_blank
+    Liquid::Template.file_system = BlankTestFileSystem.new
+    assert_template_result "foobar" * (N + 1), wrap("{% include 'foobar' %}")
+    assert_template_result " foobar " * (N + 1), wrap("{% include ' foobar ' %}")
+    assert_template_result "   " * (N + 1), wrap(" {% include ' ' %} ")
+  end
+
+  def test_case_is_blank
+    assert_template_result("", wrap(" {% assign foo = 'bar' %} {% case foo %} {% when 'bar' %} {% when 'whatever' %} {% else %} {% endcase %} "))
+    assert_template_result("", wrap(" {% assign foo = 'else' %} {% case foo %} {% when 'bar' %} {% when 'whatever' %} {% else %} {% endcase %} "))
+    assert_template_result("   x  " * (N + 1), wrap(" {% assign foo = 'else' %} {% case foo %} {% when 'bar' %} {% when 'whatever' %} {% else %} x {% endcase %} "))
+  end
+end

test/integration/block_test.rb

@@ -0,0 +1,12 @@
+require 'test_helper'
+
+class BlockTest < Minitest::Test
+  include Liquid
+
+  def test_unexpected_end_tag
+    exc = assert_raises(SyntaxError) do
+      Template.parse("{% if true %}{% endunless %}")
+    end
+    assert_equal exc.message, "Liquid syntax error: 'endunless' is not a valid delimiter for if tags. use endif"
+  end
+end

test/integration/capture_test.rb

@@ -1,12 +1,22 @@
 require 'test_helper'
 
-class CaptureTest < Test::Unit::TestCase
+class CaptureTest < Minitest::Test
   include Liquid
 
   def test_captures_block_content_in_variable
     assert_template_result("test string", "{% capture 'var' %}test string{% endcapture %}{{var}}", {})
   end
 
+  def test_capture_with_hyphen_in_variable_name
+    template_source = <<-END_TEMPLATE
+    {% capture this-thing %}Print this-thing{% endcapture %}
+    {{ this-thing }}
+    END_TEMPLATE
+    template = Template.parse(template_source)
+    rendered = template.render!
+    assert_equal "Print this-thing", rendered.strip
+  end
+
   def test_capture_to_variable_from_outer_scope_if_existing
     template_source = <<-END_TEMPLATE
     {% assign var = '' %}
@@ -19,7 +29,7 @@ class CaptureTest < Test::Unit::TestCase
     {{var}}
     END_TEMPLATE
     template = Template.parse(template_source)
-    rendered = template.render
+    rendered = template.render!
     assert_equal "test-string", rendered.gsub(/\s/, '')
   end
 
@@ -34,7 +44,7 @@ class CaptureTest < Test::Unit::TestCase
     {{ first }}-{{ second }}
     END_TEMPLATE
     template = Template.parse(template_source)
-    rendered = template.render
+    rendered = template.render!
     assert_equal "3-3", rendered.gsub(/\s/, '')
   end
 end # CaptureTest

test/integration/context_test.rb

@@ -0,0 +1,32 @@
+require 'test_helper'
+
+class ContextTest < Minitest::Test
+  include Liquid
+
+  def test_override_global_filter
+    global = Module.new do
+      def notice(output)
+        "Global #{output}"
+      end
+    end
+
+    local = Module.new do
+      def notice(output)
+        "Local #{output}"
+      end
+    end
+
+    with_global_filter(global) do
+      assert_equal 'Global test', Template.parse("{{'test' | notice }}").render!
+      assert_equal 'Local test', Template.parse("{{'test' | notice }}").render!({}, filters: [local])
+    end
+  end
+
+  def test_has_key_will_not_add_an_error_for_missing_keys
+    with_error_mode :strict do
+      context = Context.new
+      context.key?('unknown')
+      assert_empty context.errors
+    end
+  end
+end