Optimize range iteration

For loops support a range syntax for iterating a fixed number of times,
which looks like this.

```liquid
{% for i in range (1..100) %}
        ...
{% endfor %}
```

Previously, we converted these ranges to arrays using `to_a`, which
initialized an array containing each number in the range. Since all we
use these ranges for is iteration, this is far less efficient than
using a range iterator.

Doing this means that iterating over ranges now takes O(1) rather than O(n)
memory. See the PR for more benchmarks.

* Remove to_a cast on ranges
* Add ReversableRange iterator
* Add custom range-specific slicing logic

.gitignore

@@ -7,4 +7,3 @@ pkg
 .ruby-version
 Gemfile.lock
 .bundle
-.byebug_history

.rubocop.yml

@@ -1,16 +1,132 @@
 inherit_from:
-  - https://shopify.github.io/ruby-style-guide/rubocop.yml
   - .rubocop_todo.yml
-
+  - ./.rubocop_todo.yml
-require: rubocop-performance
-
-Performance:
-  Enabled: true
 
 AllCops:
   Exclude:
-    - 'vendor/bundle/**/*'
+    - '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'
+    - 'example/server/liquid_servlet.rb'

.rubocop_todo.yml

@@ -1,30 +1,36 @@
 # This configuration was generated by
 # `rubocop --auto-gen-config`
-# on 2019-09-11 06:34:25 +1000 using RuboCop version 0.74.0.
+# 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: 2
+# Offense count: 1
-Lint/AmbiguousOperator:
+# Cop supports --auto-correct.
+# Configuration parameters: Include, TreatCommentsAsGroupSeparators.
+# Include: **/*.gemspec
+Gemspec/OrderedDependencies:
   Exclude:
-    - 'test/unit/condition_unit_test.rb'
+    - 'liquid.gemspec'
 
-# Offense count: 21
+# Offense count: 5
-# Configuration parameters: AllowSafeAssignment.
+# Cop supports --auto-correct.
-Lint/AssignmentInCondition:
+# Configuration parameters: EnforcedStyle.
+# SupportedStyles: auto_detection, squiggly, active_support, powerpack, unindent
+Layout/IndentHeredoc:
   Exclude:
-    - 'lib/liquid/block_body.rb'
+    - 'test/integration/tags/for_tag_test.rb'
-    - 'lib/liquid/lexer.rb'
+    - 'test/integration/trim_mode_test.rb'
-    - 'lib/liquid/standardfilters.rb'
+
-    - 'lib/liquid/tags/for.rb'
+# Offense count: 6
-    - 'lib/liquid/tags/if.rb'
+# Cop supports --auto-correct.
-    - 'lib/liquid/tags/raw.rb'
+# Configuration parameters: EnforcedStyle.
-    - 'lib/liquid/variable.rb'
+# SupportedStyles: symmetrical, new_line, same_line
-    - 'performance/profile.rb'
+Layout/MultilineMethodCallBraceLayout:
-    - 'test/test_helper.rb'
+  Exclude:
-    - 'test/unit/tokenizer_unit_test.rb'
+    - 'test/integration/error_handling_test.rb'
+    - 'test/unit/strainer_unit_test.rb'
 
 # Offense count: 2
 # Cop supports --auto-correct.
@@ -34,62 +40,181 @@ Lint/InheritException:
   Exclude:
     - 'lib/liquid/interrupts.rb'
 
-# Offense count: 2
-Lint/UselessAssignment:
-  Exclude:
-    - 'performance/shopify/database.rb'
-
 # Offense count: 1
 # Configuration parameters: CheckForMethodsWithNoSideEffects.
 Lint/Void:
   Exclude:
     - 'lib/liquid/parse_context.rb'
 
-# Offense count: 98
+# Offense count: 54
-# Cop supports --auto-correct.
+Metrics/AbcSize:
-# Configuration parameters: AutoCorrect, AllowHeredoc, AllowURI, URISchemes, IgnoreCopDirectives, IgnoredPatterns.
+  Max: 56
-# URISchemes: http, https
-Metrics/LineLength:
-  Max: 294
 
-# Offense count: 44
+# Offense count: 12
-Naming/ConstantName:
+Metrics/CyclomaticComplexity:
-  Exclude:
+  Max: 12
-    - 'lib/liquid.rb'
-    - 'lib/liquid/block_body.rb'
-    - 'lib/liquid/tags/assign.rb'
-    - 'lib/liquid/tags/capture.rb'
-    - 'lib/liquid/tags/case.rb'
-    - 'lib/liquid/tags/cycle.rb'
-    - 'lib/liquid/tags/for.rb'
-    - 'lib/liquid/tags/if.rb'
-    - 'lib/liquid/tags/include.rb'
-    - 'lib/liquid/tags/raw.rb'
-    - 'lib/liquid/tags/table_row.rb'
-    - 'lib/liquid/variable.rb'
-    - 'performance/shopify/comment_form.rb'
-    - 'performance/shopify/paginate.rb'
-    - 'test/integration/tags/include_tag_test.rb'
 
-# Offense count: 5
+# Offense count: 112
-Style/ClassVars:
+# 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/strainer.rb'
+    - 'lib/liquid/context.rb'
-    - 'lib/liquid/template.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
-# Configuration parameters: AllowCoercion.
 Style/DateTime:
   Exclude:
     - 'test/unit/context_unit_test.rb'
 
-# Offense count: 119
+# 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: always, never
+# SupportedStyles: compact, expanded
-Style/FrozenStringLiteralComment:
+Style/EmptyMethod:
-  Enabled: false
+  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.
@@ -99,3 +224,37 @@ Style/Semicolon:
     - '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

@@ -1,30 +1,31 @@
 language: ruby
-cache: bundler
 
 rvm:
+  - 2.1
+  - 2.2
+  - 2.3
   - 2.4
   - 2.5
-  - &latest_ruby 2.6
-  - 2.7
   - ruby-head
   - jruby-head
-  - truffleruby
+#  - rbx-2
+
+sudo: false
+
+addons:
+  apt:
+    packages:
+    - libgmp3-dev
 
 matrix:
-  include:
-    - rvm: *latest_ruby
-      script: bundle exec rake memory_profile:run
-      name: Profiling Memory Usage
   allow_failures:
     - rvm: ruby-head
     - rvm: jruby-head
-    - rvm: truffleruby
 
-branches:
+install:
-  only:
+  - bundle install
-    - master
+
-    - gh-pages
+script: bundle exec rake
-    - /.*-stable/
 
 notifications:
   disable: true

Gemfile

@@ -8,18 +8,16 @@ gemspec
 group :benchmark, :test do
   gem 'benchmark-ips'
   gem 'memory_profiler'
-  gem 'terminal-table'
 
-  install_if -> { RUBY_PLATFORM !~ /mingw|mswin|java/ && RUBY_ENGINE != 'truffleruby' } do
+  install_if -> { RUBY_PLATFORM !~ /mingw|mswin|java/ } do
     gem 'stackprof'
   end
 end
 
 group :test do
-  gem 'rubocop', '~> 0.74.0', require: false
+  gem 'rubocop', '~> 0.53.0'
-  gem 'rubocop-performance', require: false
 
-  platform :mri, :truffleruby do
+  platform :mri do
-    gem 'liquid-c', github: 'Shopify/liquid-c', ref: 'liquid-tag'
+    gem 'liquid-c', github: 'Shopify/liquid-c', ref: 'reversable-range'
   end
 end

Rakefile

@@ -1,31 +1,29 @@
 require 'rake'
 require 'rake/testtask'
-$LOAD_PATH.unshift(File.expand_path("../lib", __FILE__))
+$LOAD_PATH.unshift File.expand_path("../lib", __FILE__)
 require "liquid/version"
 
-task(default: [:test, :rubocop])
+task default: [:test, :rubocop]
 
-desc('run test suite with default parser')
+desc 'run test suite with default parser'
 Rake::TestTask.new(:base_test) do |t|
   t.libs << '.' << 'lib' << 'test'
   t.test_files = FileList['test/{integration,unit}/**/*_test.rb']
   t.verbose = false
 end
 
-desc('run test suite with warn error mode')
+desc 'run test suite with warn error mode'
 task :warn_test do
   ENV['LIQUID_PARSER_MODE'] = 'warn'
   Rake::Task['base_test'].invoke
 end
 
 task :rubocop do
-  if RUBY_ENGINE == 'ruby'
+  require 'rubocop/rake_task'
-    require 'rubocop/rake_task'
+  RuboCop::RakeTask.new
-    RuboCop::RakeTask.new
-  end
 end
 
-desc('runs test suite with both strict and lax parsers')
+desc 'runs test suite with both strict and lax parsers'
 task :test do
   ENV['LIQUID_PARSER_MODE'] = 'lax'
   Rake::Task['base_test'].invoke
@@ -34,8 +32,8 @@ task :test do
   Rake::Task['base_test'].reenable
   Rake::Task['base_test'].invoke
 
-  if RUBY_ENGINE == 'ruby' || RUBY_ENGINE == 'truffleruby'
+  if RUBY_ENGINE == 'ruby'
-    ENV['LIQUID_C'] = '1'
+    ENV['LIQUID-C'] = '1'
 
     ENV['LIQUID_PARSER_MODE'] = 'lax'
     Rake::Task['base_test'].reenable
@@ -47,7 +45,7 @@ task :test do
   end
 end
 
-task(gem: :build)
+task gem: :build
 task :build do
   system "gem build liquid.gemspec"
 end
@@ -94,7 +92,7 @@ namespace :memory_profile do
   end
 end
 
-desc("Run example")
+desc "Run example"
 task :example do
   ruby "-w -d -Ilib example/server/server.rb"
 end

example/server/example_servlet.rb

@@ -1,6 +1,6 @@
 module ProductsFilter
   def price(integer)
-    format("$%.2d USD", integer / 100.0)
+    sprintf("$%.2d USD", integer / 100.0)
   end
 
   def prettyprint(text)

example/server/liquid_servlet.rb

@@ -9,12 +9,12 @@ class LiquidServlet < WEBrick::HTTPServlet::AbstractServlet
 
   private
 
-  def handle(_type, req, res)
+  def handle(type, req, res)
     @request = req
     @response = res
 
     @request.path_info =~ /(\w+)\z/
-    @action = Regexp.last_match(1) || 'index'
+    @action = $1 || 'index'
     @assigns = send(@action) if respond_to?(@action)
 
     @response['Content-Type'] = "text/html"

example/server/server.rb

@@ -8,5 +8,5 @@ require_relative 'example_servlet'
 # Setup webrick
 server = WEBrick::HTTPServer.new(Port: ARGV[1] || 3000)
 server.mount('/', Servlet)
-trap("INT") { server.shutdown }
+trap("INT"){ server.shutdown }
 server.start

lib/liquid.rb

@@ -74,7 +74,7 @@ require 'liquid/condition'
 require 'liquid/utils'
 require 'liquid/tokenizer'
 require 'liquid/parse_context'
-require 'liquid/partial_cache'
+require 'liquid/reversable_range'
 
 # Load all the tags of the standard library
 #

lib/liquid/block.rb

@@ -13,7 +13,6 @@ module Liquid
       end
     end
 
-    # For backwards compatibility
     def render(context)
       @body.render(context)
     end
@@ -28,15 +27,15 @@ module Liquid
 
     def unknown_tag(tag, _params, _tokens)
       if tag == 'else'.freeze
-        raise SyntaxError, parse_context.locale.t("errors.syntax.unexpected_else".freeze,
+        raise SyntaxError.new(parse_context.locale.t("errors.syntax.unexpected_else".freeze,
-          block_name: block_name)
+          block_name: block_name))
       elsif tag.start_with?('end'.freeze)
-        raise SyntaxError, parse_context.locale.t("errors.syntax.invalid_delimiter".freeze,
+        raise SyntaxError.new(parse_context.locale.t("errors.syntax.invalid_delimiter".freeze,
           tag: tag,
           block_name: block_name,
-          block_delimiter: block_delimiter)
+          block_delimiter: block_delimiter))
       else
-        raise SyntaxError, parse_context.locale.t("errors.syntax.unknown_tag".freeze, tag: tag)
+        raise SyntaxError.new(parse_context.locale.t("errors.syntax.unknown_tag".freeze, tag: tag))
       end
     end
 
@@ -61,7 +60,7 @@ module Liquid
 
           return false if end_tag_name == block_delimiter
           unless end_tag_name
-            raise SyntaxError, parse_context.locale.t("errors.syntax.tag_never_closed".freeze, block_name: block_name)
+            raise SyntaxError.new(parse_context.locale.t("errors.syntax.tag_never_closed".freeze, block_name: block_name))
           end
 
           # this tag is not registered with the system

lib/liquid/block_body.rb

@@ -1,7 +1,6 @@
 module Liquid
   class BlockBody
-    LiquidTagToken = /\A\s*(\w+)\s*(.*?)\z/o
+    FullToken = /\A#{TagStart}#{WhitespaceControl}?\s*(\w+)\s*(.*?)#{WhitespaceControl}?#{TagEnd}\z/om
-    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
@@ -14,42 +13,8 @@ module Liquid
       @blank = true
     end
 
-    def parse(tokenizer, parse_context, &block)
+    def parse(tokenizer, parse_context)
       parse_context.line_number = tokenizer.line_number
-
-      if tokenizer.for_liquid_tag
-        parse_for_liquid_tag(tokenizer, parse_context, &block)
-      else
-        parse_for_document(tokenizer, parse_context, &block)
-      end
-    end
-
-    private def parse_for_liquid_tag(tokenizer, parse_context)
-      while token = tokenizer.shift
-        unless token.empty? || token =~ WhitespaceOrNothing
-          unless token =~ LiquidTagToken
-            # line isn't empty but didn't match tag syntax, yield and let the
-            # caller raise a syntax error
-            return yield token, token
-          end
-          tag_name = Regexp.last_match(1)
-          markup = Regexp.last_match(2)
-          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
-        end
-        parse_context.line_number = tokenizer.line_number
-      end
-
-      yield nil, nil
-    end
-
-    private def parse_for_document(tokenizer, parse_context, &block)
       while token = tokenizer.shift
         next if token.empty?
         case
@@ -58,20 +23,9 @@ module Liquid
           unless token =~ FullToken
             raise_missing_tag_terminator(token, parse_context)
           end
-          tag_name = Regexp.last_match(2)
+          tag_name = $1
-          markup = Regexp.last_match(4)
+          markup = $2
-
+          # fetch the tag from registered blocks
-          if parse_context.line_number
-            # newlines inside the tag should increase the line number,
-            # particularly important for multiline {% liquid %} tags
-            parse_context.line_number += Regexp.last_match(1).count("\n".freeze) + Regexp.last_match(3).count("\n".freeze)
-          end
-
-          if tag_name == 'liquid'.freeze
-            liquid_tag_tokenizer = Tokenizer.new(markup, line_number: parse_context.line_number, for_liquid_tag: true)
-            next parse_for_liquid_tag(liquid_tag_tokenizer, parse_context, &block)
-          end
-
           unless tag = registered_tags[tag_name]
             # end parsing if we reach an unknown tag and let the caller decide
             # determine how to proceed
@@ -101,7 +55,7 @@ module Liquid
     def whitespace_handler(token, parse_context)
       if token[2] == WhitespaceControl
         previous_token = @nodelist.last
-        if previous_token.is_a?(String)
+        if previous_token.is_a? String
           previous_token.rstrip!
         end
       end
@@ -113,23 +67,19 @@ module Liquid
     end
 
     def render(context)
-      render_to_output_buffer(context, '')
+      output = []
-    end
-
-    def render_to_output_buffer(context, output)
       context.resource_limits.render_score += @nodelist.length
 
       idx = 0
       while node = @nodelist[idx]
-        previous_output_size = output.bytesize
-
         case node
         when String
+          check_resources(context, node)
           output << node
         when Variable
-          render_node(context, output, node)
+          render_node_to_output(node, output, context)
         when Block
-          render_node(context, node.blank? ? '' : output, node)
+          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
@@ -138,32 +88,36 @@ module Liquid
           context.push_interrupt(node.interrupt)
           break
         else # Other non-Block tags
-          render_node(context, output, node)
+          render_node_to_output(node, output, context)
           break if context.interrupt? # might have happened through an include
         end
         idx += 1
-
-        raise_if_resource_limits_reached(context, output.bytesize - previous_output_size)
       end
 
-      output
+      output.join
     end
 
     private
 
-    def render_node(context, output, node)
+    def render_node_to_output(node, output, context, skip_output = false)
-      node.render_to_output_buffer(context, output)
+      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 raise_if_resource_limits_reached(context, length)
+    def check_resources(context, node_output)
-      context.resource_limits.render_length += length
+      context.resource_limits.render_length += node_output.bytesize
       return unless context.resource_limits.reached?
-      raise MemoryError, "Memory limits exceeded".freeze
+      raise MemoryError.new("Memory limits exceeded".freeze)
     end
 
     def create_variable(token, parse_context)
@@ -175,11 +129,11 @@ module Liquid
     end
 
     def raise_missing_tag_terminator(token, parse_context)
-      raise SyntaxError, parse_context.locale.t("errors.syntax.tag_termination".freeze, token: token, tag_end: TagEnd.inspect)
+      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, parse_context.locale.t("errors.syntax.variable_termination".freeze, token: token, tag_end: VariableEnd.inspect)
+      raise SyntaxError.new(parse_context.locale.t("errors.syntax.variable_termination".freeze, token: token, tag_end: VariableEnd.inspect))
     end
 
     def registered_tags

lib/liquid/condition.rb

@@ -11,18 +11,18 @@ module Liquid
       '=='.freeze => ->(cond, left, right) {  cond.send(:equal_variables, left, right) },
       '!='.freeze => ->(cond, left, right) { !cond.send(:equal_variables, left, right) },
       '<>'.freeze => ->(cond, left, right) { !cond.send(:equal_variables, left, right) },
-      '<'.freeze => :<,
+      '<'.freeze  => :<,
-      '>'.freeze => :>,
+      '>'.freeze  => :>,
       '>='.freeze => :>=,
       '<='.freeze => :<=,
-      'contains'.freeze => lambda do |_cond, left, right|
+      '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,
+      end
     }
 
     def self.operators
@@ -36,7 +36,7 @@ module Liquid
       @left = left
       @operator = operator
       @right = right
-      @child_relation = nil
+      @child_relation  = nil
       @child_condition = nil
     end
 
@@ -116,7 +116,7 @@ module Liquid
       left = context.evaluate(left)
       right = context.evaluate(right)
 
-      operation = self.class.operators[op] || raise(Liquid::ArgumentError, "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)
@@ -124,7 +124,7 @@ module Liquid
         begin
           left.send(operation, right)
         rescue ::ArgumentError => e
-          raise Liquid::ArgumentError, e.message
+          raise Liquid::ArgumentError.new(e.message)
         end
       end
     end

lib/liquid/context.rb

@@ -12,41 +12,30 @@ module Liquid
   #
   #   context['bob']  #=> nil  class Context
   class Context
-    attr_reader :scopes, :errors, :registers, :environments, :resource_limits, :static_registers, :static_environments
+    attr_reader :scopes, :errors, :registers, :environments, :resource_limits
     attr_accessor :exception_renderer, :template_name, :partial, :global_filter, :strict_variables, :strict_filters
 
-    # rubocop:disable Metrics/ParameterLists
+    def initialize(environments = {}, outer_scope = {}, registers = {}, rethrow_errors = false, resource_limits = nil)
-    def self.build(environments: {}, outer_scope: {}, registers: {}, rethrow_errors: false, resource_limits: nil, static_registers: {}, static_environments: {})
+      @environments     = [environments].flatten
-      new(environments, outer_scope, registers, rethrow_errors, resource_limits, static_registers, static_environments)
+      @scopes           = [(outer_scope || {})]
-    end
+      @registers        = registers
-
+      @errors           = []
-    def initialize(environments = {}, outer_scope = {}, registers = {}, rethrow_errors = false, resource_limits = nil, static_registers = {}, static_environments = {})
+      @partial          = false
-      @environments = [environments]
+      @strict_variables = false
-      @environments.flatten!
+      @resource_limits  = resource_limits || ResourceLimits.new(Template.default_resource_limits)
-
-      @static_environments = [static_environments].flat_map(&:freeze).freeze
-      @scopes              = [(outer_scope || {})]
-      @registers           = registers
-      @static_registers    = static_registers.freeze
-      @errors              = []
-      @partial             = false
-      @strict_variables    = false
-      @resource_limits     = resource_limits || ResourceLimits.new(Template.default_resource_limits)
-      @base_scope_depth    = 0
       squash_instance_assigns_with_environments
 
       @this_stack_used = false
 
       self.exception_renderer = Template.default_exception_renderer
       if rethrow_errors
-        self.exception_renderer = ->(_e) { raise }
+        self.exception_renderer = ->(e) { raise }
       end
 
       @interrupts = []
       @filters = []
       @global_filter = nil
     end
-    # rubocop:enable Metrics/ParameterLists
 
     def warnings
       @warnings ||= []
@@ -100,7 +89,7 @@ module Liquid
     # Push new local scope on the stack. use <tt>Context#stack</tt> instead
     def push(new_scope = {})
       @scopes.unshift(new_scope)
-      check_overflow
+      raise StackLevelError, "Nesting too deep".freeze if @scopes.length > Block::MAX_DEPTH
     end
 
     # Merge a hash of variables in the current local scope
@@ -137,25 +126,6 @@ module Liquid
       @this_stack_used = old_stack_used
     end
 
-    # Creates a new context inheriting resource limits, filters, environment etc.,
-    # but with an isolated scope.
-    def new_isolated_subcontext
-      check_overflow
-
-      Context.build(
-        resource_limits: resource_limits,
-        static_environments: static_environments,
-        static_registers: static_registers
-      ).tap do |subcontext|
-        subcontext.base_scope_depth = base_scope_depth + 1
-        subcontext.exception_renderer = exception_renderer
-        subcontext.filters = @filters
-        subcontext.strainer = nil
-        subcontext.errors = errors
-        subcontext.warnings = warnings
-      end
-    end
-
     def clear_instance_assigns
       @scopes[0] = {}
     end
@@ -194,13 +164,25 @@ module Liquid
       # This was changed from find() to find_index() because this is a very hot
       # path and find_index() is optimized in MRI to reduce object allocation
       index = @scopes.find_index { |s| s.key?(key) }
+      scope = @scopes[index] if index
 
-      variable = if index
+      variable = nil
-        lookup_and_evaluate(@scopes[index], key, raise_on_not_found: raise_on_not_found)
+
-      else
+      if scope.nil?
-        try_variable_find_in_environments(key, raise_on_not_found: raise_on_not_found)
+        @environments.each do |e|
+          variable = lookup_and_evaluate(e, key, raise_on_not_found: raise_on_not_found)
+          # When lookup returned a value OR there is no value but the lookup also did not raise
+          # then it is the value we are looking for.
+          if !variable.nil? || @strict_variables && raise_on_not_found
+            scope = e
+            break
+          end
+        end
       end
 
+      scope ||= @environments.last || @scopes.last
+      variable ||= lookup_and_evaluate(scope, key, raise_on_not_found: raise_on_not_found)
+
       variable = variable.to_liquid
       variable.context = self if variable.respond_to?(:context=)
 
@@ -215,44 +197,14 @@ module Liquid
       value = obj[key]
 
       if value.is_a?(Proc) && obj.respond_to?(:[]=)
-        obj[key] = value.arity == 0 ? value.call : value.call(self)
+        obj[key] = (value.arity == 0) ? value.call : value.call(self)
       else
         value
       end
     end
 
-    protected
-
-    attr_writer :base_scope_depth, :warnings, :errors, :strainer, :filters
-
     private
 
-    attr_reader :base_scope_depth
-
-    def try_variable_find_in_environments(key, raise_on_not_found:)
-      @environments.each do |environment|
-        found_variable = lookup_and_evaluate(environment, key, raise_on_not_found: raise_on_not_found)
-        if !found_variable.nil? || @strict_variables && raise_on_not_found
-          return found_variable
-        end
-      end
-      @static_environments.each do |environment|
-        found_variable = lookup_and_evaluate(environment, key, raise_on_not_found: raise_on_not_found)
-        if !found_variable.nil? || @strict_variables && raise_on_not_found
-          return found_variable
-        end
-      end
-      nil
-    end
-
-    def check_overflow
-      raise StackLevelError, "Nesting too deep".freeze if overflow?
-    end
-
-    def overflow?
-      base_scope_depth + @scopes.length > Block::MAX_DEPTH
-    end
-
     def internal_error
       # raise and catch to set backtrace and cause on exception
       raise Liquid::InternalError, 'internal'

lib/liquid/document.rb

@@ -7,7 +7,7 @@ module Liquid
     end
 
     def parse(tokens, parse_context)
-      super do |end_tag_name, _end_tag_params|
+      super do |end_tag_name, end_tag_params|
         unknown_tag(end_tag_name, parse_context) if end_tag_name
       end
     rescue SyntaxError => e
@@ -18,9 +18,9 @@ module Liquid
     def unknown_tag(tag, parse_context)
       case tag
       when 'else'.freeze, 'end'.freeze
-        raise SyntaxError, parse_context.locale.t("errors.syntax.unexpected_outer_tag".freeze, tag: tag)
+        raise SyntaxError.new(parse_context.locale.t("errors.syntax.unexpected_outer_tag".freeze, tag: tag))
       else
-        raise SyntaxError, parse_context.locale.t("errors.syntax.unknown_tag".freeze, tag: tag)
+        raise SyntaxError.new(parse_context.locale.t("errors.syntax.unknown_tag".freeze, tag: tag))
       end
     end
   end

lib/liquid/drop.rb

@@ -25,7 +25,7 @@ module Liquid
 
     # Catch all for the method
     def liquid_method_missing(method)
-      return nil unless @context&.strict_variables
+      return nil unless @context && @context.strict_variables
       raise Liquid::UndefinedDropMethod, "undefined method #{method}"
     end
 

lib/liquid/errors.rb

@@ -21,10 +21,10 @@ module Liquid
 
     def message_prefix
       str = ""
-      str << if is_a?(SyntaxError)
+      if is_a?(SyntaxError)
-        "Liquid syntax error"
+        str << "Liquid syntax error"
       else
-        "Liquid error"
+        str << "Liquid error"
       end
 
       if line_number

lib/liquid/expression.rb

@@ -15,7 +15,7 @@ module Liquid
 
     LITERALS = {
       nil => nil, 'nil'.freeze => nil, 'null'.freeze => nil, ''.freeze => nil,
-      'true'.freeze => true,
+      'true'.freeze  => true,
       'false'.freeze => false,
       'blank'.freeze => MethodLiteral.new(:blank?, '').freeze,
       'empty'.freeze => MethodLiteral.new(:empty?, '').freeze
@@ -33,13 +33,13 @@ module Liquid
       else
         case markup
         when SINGLE_QUOTED_STRING, DOUBLE_QUOTED_STRING
-          Regexp.last_match(1)
+          $1
         when INTEGERS_REGEX
-          Regexp.last_match(1).to_i
+          $1.to_i
         when RANGES_REGEX
-          RangeLookup.parse(Regexp.last_match(1), Regexp.last_match(2))
+          RangeLookup.parse($1, $2)
         when FLOATS_REGEX
-          Regexp.last_match(1).to_f
+          $1.to_f
         else
           VariableLookup.parse(markup)
         end

lib/liquid/file_system.rb

@@ -57,7 +57,7 @@ module Liquid
     end
 
     def full_path(template_path)
-      raise FileSystemError, "Illegal template name '#{template_path}'" unless template_path =~ %r{\A[^./][a-zA-Z0-9_/]+\z}
+      raise FileSystemError, "Illegal template name '#{template_path}'" unless template_path =~ /\A[^.\/][a-zA-Z0-9_\/]+\z/
 
       full_path = if template_path.include?('/'.freeze)
         File.join(root, File.dirname(template_path), @pattern % File.basename(template_path))

lib/liquid/i18n.rb

@@ -26,13 +26,13 @@ module Liquid
     def interpolate(name, vars)
       name.gsub(/%\{(\w+)\}/) do
         # raise TranslationError, "Undefined key #{$1} for interpolation in translation #{name}"  unless vars[$1.to_sym]
-        (vars[Regexp.last_match(1).to_sym]).to_s
+        (vars[$1.to_sym]).to_s
       end
     end
 
     def deep_fetch_translation(name)
       name.split('.'.freeze).reduce(locale) do |level, cur|
-        level[cur] || raise(TranslationError, "Translation for #{name} does not exist in locale #{path}")
+        level[cur] or raise TranslationError, "Translation for #{name} does not exist in locale #{path}"
       end
     end
   end

lib/liquid/lexer.rb

@@ -11,7 +11,7 @@ module Liquid
       '('.freeze => :open_round,
       ')'.freeze => :close_round,
       '?'.freeze => :question,
-      '-'.freeze => :dash,
+      '-'.freeze => :dash
     }.freeze
     IDENTIFIER = /[a-zA-Z_][\w-]*\??/
     SINGLE_STRING_LITERAL = /'[^\']*'/
@@ -31,12 +31,13 @@ module Liquid
       until @ss.eos?
         @ss.skip(WHITESPACE_OR_NOTHING)
         break if @ss.eos?
-        tok = if t = @ss.scan(COMPARISON_OPERATOR) then [:comparison, t]
+        tok = case
-        elsif t = @ss.scan(SINGLE_STRING_LITERAL) then [:string, t]
+        when t = @ss.scan(COMPARISON_OPERATOR) then [:comparison, t]
-        elsif t = @ss.scan(DOUBLE_STRING_LITERAL) then [:string, t]
+        when t = @ss.scan(SINGLE_STRING_LITERAL) then [:string, t]
-        elsif t = @ss.scan(NUMBER_LITERAL) then [:number, t]
+        when t = @ss.scan(DOUBLE_STRING_LITERAL) then [:string, t]
-        elsif t = @ss.scan(IDENTIFIER) then [:id, t]
+        when t = @ss.scan(NUMBER_LITERAL) then [:number, t]
-        elsif t = @ss.scan(DOTDOT) then [:dotdot, 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]

lib/liquid/locales/en.yml

@@ -22,6 +22,5 @@
       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"
-      render: "Syntax error in tag 'render' - Template name must be a quoted string"
     argument:
       include: "Argument error in tag 'include' - Illegal template name"

lib/liquid/parse_context.rb

@@ -28,7 +28,7 @@ module Liquid
         if dont_pass == true
           { locale: locale }
         elsif dont_pass.is_a?(Array)
-          @template_options.reject { |k, _v| dont_pass.include?(k) }
+          @template_options.reject { |k, v| dont_pass.include?(k) }
         else
           @template_options
         end

lib/liquid/parse_tree_visitor.rb

@@ -28,7 +28,7 @@ module Liquid
         item, new_context = @callbacks[node.class].call(node, context)
         [
           item,
-          ParseTreeVisitor.for(node, @callbacks).visit(new_context || context),
+          ParseTreeVisitor.for(node, @callbacks).visit(new_context || context)
         ]
       end
     end

lib/liquid/parser.rb

@@ -44,14 +44,11 @@ module Liquid
       tok[0] == type
     end
 
-    SINGLE_TOKEN_EXPRESSION_TYPES = [:string, :number].freeze
-    private_constant :SINGLE_TOKEN_EXPRESSION_TYPES
-
     def expression
       token = @tokens[@p]
       if token[0] == :id
         variable_signature
-      elsif SINGLE_TOKEN_EXPRESSION_TYPES.include?(token[0])
+      elsif [:string, :number].include? token[0]
         consume
       elsif token.first == :open_round
         consume

lib/liquid/partial_cache.rb

@@ -1,18 +0,0 @@
-module Liquid
-  class PartialCache
-    def self.load(template_name, context:, parse_context:)
-      cached_partials = (context.registers[:cached_partials] ||= {})
-      cached = cached_partials[template_name]
-      return cached if cached
-
-      file_system = (context.registers[:file_system] ||= Liquid::Template.file_system)
-      source = file_system.read_template_file(template_name)
-      parse_context.partial = true
-
-      partial = Liquid::Template.parse(source, parse_context)
-      cached_partials[template_name] = partial
-    ensure
-      parse_context.partial = false
-    end
-  end
-end

lib/liquid/profiler/hooks.rb

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

lib/liquid/range_lookup.rb

@@ -6,7 +6,7 @@ module Liquid
       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
+        ReversableRange.new(start_obj.to_i, end_obj.to_i)
       end
     end
 
@@ -18,7 +18,7 @@ module Liquid
     def evaluate(context)
       start_int = to_integer(context.evaluate(@start_obj))
       end_int = to_integer(context.evaluate(@end_obj))
-      start_int..end_int
+      ReversableRange.new(start_int, end_int)
     end
 
     private

lib/liquid/reversable_range.rb

@@ -0,0 +1,77 @@
+module Liquid
+  class ReversableRange
+    include Enumerable
+
+    def initialize(min, max)
+      @min = min
+      @max = max
+      @reversed = false
+    end
+
+    def each
+      if reversed
+        index = max
+        while index >= min
+          yield index
+          index -= 1
+        end
+      else
+        index = min
+        while index <= max
+          yield index
+          index += 1
+        end
+      end
+    end
+
+    def reverse!
+      @reversed = !reversed
+      self
+    end
+
+    def empty?
+      max < min
+    end
+
+    def size
+      difference = max - min
+      if difference > 0
+        difference + 1
+      else
+        0
+      end
+    end
+
+    def load_slice(from, to = nil)
+      to ||= max
+      slice_max = [max, to].min
+      slice_min = [min, from].max
+      range = ReversableRange.new(slice_min, slice_max)
+      range.reverse! if reversed
+      range
+    end
+
+    def ==(other)
+      other.is_a?(self.class) &&
+        other.min == min &&
+        other.max == max &&
+        other.reversed == reversed
+    end
+
+    def to_s
+      if reversed
+        "#{max}..#{min}"
+      else
+        "#{min}..#{max}"
+      end
+    end
+
+    def to_liquid
+      self
+    end
+
+    protected
+
+    attr_reader :min, :max, :reversed
+  end
+end

lib/liquid/standardfilters.rb

@@ -8,13 +8,13 @@ module Liquid
       '>'.freeze => '>'.freeze,
       '<'.freeze => '&lt;'.freeze,
       '"'.freeze => '&quot;'.freeze,
-      "'".freeze => '&#39;'.freeze,
+      "'".freeze => '&#39;'.freeze
     }.freeze
     HTML_ESCAPE_ONCE_REGEXP = /["><']|&(?!([a-zA-Z]+|(#\d+));)/
     STRIP_HTML_BLOCKS = Regexp.union(
-      %r{<script.*?</script>}m,
+      /<script.*?<\/script>/m,
       /<!--.*?-->/m,
-      %r{<style.*?</style>}m
+      /<style.*?<\/style>/m
     )
     STRIP_HTML_TAGS = /<.*?>/m
 
@@ -79,7 +79,7 @@ module Liquid
       truncate_string_str = truncate_string.to_s
       l = length - truncate_string_str.length
       l = 0 if l < 0
-      input_str.length > length ? input_str[0...l].concat(truncate_string_str) : input_str
+      input_str.length > length ? input_str[0...l] + truncate_string_str : input_str
     end
 
     def truncatewords(input, words = 15, truncate_string = "...".freeze)
@@ -88,7 +88,7 @@ module Liquid
       words = Utils.to_integer(words)
       l = words - 1
       l = 0 if l < 0
-      wordlist.length > l ? wordlist[0..l].join(" ".freeze).concat(truncate_string.to_s) : input
+      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.
@@ -276,7 +276,7 @@ module Liquid
 
     def concat(input, array)
       unless array.respond_to?(:to_ary)
-        raise ArgumentError, "concat filter requires an array argument"
+        raise ArgumentError.new("concat filter requires an array argument")
       end
       InputIterator.new(input).concat(array)
     end
@@ -430,7 +430,7 @@ module Liquid
     private
 
     def raise_property_error(property)
-      raise Liquid::ArgumentError, "cannot select the property '#{property}'"
+      raise Liquid::ArgumentError.new("cannot select the property '#{property}'")
     end
 
     def apply_operation(input, operand, operation)

lib/liquid/strainer.rb

@@ -27,7 +27,7 @@ module Liquid
 
     def self.add_filter(filter)
       raise ArgumentError, "Expected module but got: #{filter.class}" unless filter.is_a?(Module)
-      unless include?(filter)
+      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(', ')}"
@@ -54,7 +54,7 @@ module Liquid
     def invoke(method, *args)
       if self.class.invokable?(method)
         send(method, *args)
-      elsif @context&.strict_filters
+      elsif @context && @context.strict_filters
         raise Liquid::UndefinedFilter, "undefined filter #{method}"
       else
         args.first

lib/liquid/tag.rb

@@ -5,8 +5,8 @@ module Liquid
     include ParserSwitching
 
     class << self
-      def parse(tag_name, markup, tokenizer, parse_context)
+      def parse(tag_name, markup, tokenizer, options)
-        tag = new(tag_name, markup, parse_context)
+        tag = new(tag_name, markup, options)
         tag.parse(tokenizer)
         tag
       end
@@ -36,14 +36,6 @@ module Liquid
       ''.freeze
     end
 
-    # For backwards compatibility with custom tags. In a future release, the semantics
-    # of the `render_to_output_buffer` method will become the default and the `render`
-    # method will be removed.
-    def render_to_output_buffer(context, output)
-      output << render(context)
-      output
-    end
-
     def blank?
       false
     end

lib/liquid/tags/assign.rb

@@ -10,27 +10,23 @@ module Liquid
   class Assign < Tag
     Syntax = /(#{VariableSignature}+)\s*=\s*(.*)\s*/om
 
-    def self.syntax_error_translation_key
-      "errors.syntax.assign".freeze
-    end
-
     attr_reader :to, :from
 
     def initialize(tag_name, markup, options)
       super
       if markup =~ Syntax
-        @to = Regexp.last_match(1)
+        @to = $1
-        @from = Variable.new(Regexp.last_match(2), options)
+        @from = Variable.new($2, options)
       else
-        raise SyntaxError, options[:locale].t(self.class.syntax_error_translation_key)
+        raise SyntaxError.new options[:locale].t("errors.syntax.assign".freeze)
       end
     end
 
-    def render_to_output_buffer(context, output)
+    def render(context)
       val = @from.render(context)
       context.scopes.last[@to] = val
       context.resource_limits.assign_score += assign_score_of(val)
-      output
+      ''.freeze
     end
 
     def blank?

lib/liquid/tags/capture.rb

@@ -16,18 +16,17 @@ module Liquid
     def initialize(tag_name, markup, options)
       super
       if markup =~ Syntax
-        @to = Regexp.last_match(1)
+        @to = $1
       else
-        raise SyntaxError, options[:locale].t("errors.syntax.capture")
+        raise SyntaxError.new(options[:locale].t("errors.syntax.capture"))
       end
     end
 
-    def render_to_output_buffer(context, output)
+    def render(context)
-      previous_output_size = output.bytesize
+      output = super
-      super
       context.scopes.last[@to] = output
-      context.resource_limits.assign_score += (output.bytesize - previous_output_size)
+      context.resource_limits.assign_score += output.bytesize
-      output
+      ''.freeze
     end
 
     def blank?

lib/liquid/tags/case.rb

@@ -10,15 +10,17 @@ module Liquid
       @blocks = []
 
       if markup =~ Syntax
-        @left = Expression.parse(Regexp.last_match(1))
+        @left = Expression.parse($1)
       else
-        raise SyntaxError, options[:locale].t("errors.syntax.case".freeze)
+        raise SyntaxError.new(options[:locale].t("errors.syntax.case".freeze))
       end
     end
 
     def parse(tokens)
       body = BlockBody.new
-      body = @blocks.last.attachment while parse_body(body, tokens)
+      while parse_body(body, tokens)
+        body = @blocks.last.attachment
+      end
     end
 
     def nodelist
@@ -36,21 +38,21 @@ module Liquid
       end
     end
 
-    def render_to_output_buffer(context, output)
+    def render(context)
       context.stack do
         execute_else_block = true
 
+        output = ''
         @blocks.each do |block|
           if block.else?
-            block.attachment.render_to_output_buffer(context, output) if execute_else_block
+            return block.attachment.render(context) if execute_else_block
           elsif block.evaluate(context)
             execute_else_block = false
-            block.attachment.render_to_output_buffer(context, output)
+            output << block.attachment.render(context)
           end
         end
+        output
       end
-
-      output
     end
 
     private
@@ -60,12 +62,12 @@ module Liquid
 
       while markup
         unless markup =~ WhenSyntax
-          raise SyntaxError, options[:locale].t("errors.syntax.case_invalid_when".freeze)
+          raise SyntaxError.new(options[:locale].t("errors.syntax.case_invalid_when".freeze))
         end
 
-        markup = Regexp.last_match(2)
+        markup = $2
 
-        block = Condition.new(@left, '=='.freeze, Expression.parse(Regexp.last_match(1)))
+        block = Condition.new(@left, '=='.freeze, Expression.parse($1))
         block.attach(body)
         @blocks << block
       end
@@ -73,7 +75,7 @@ module Liquid
 
     def record_else_condition(markup)
       unless markup.strip.empty?
-        raise SyntaxError, options[:locale].t("errors.syntax.case_invalid_else".freeze)
+        raise SyntaxError.new(options[:locale].t("errors.syntax.case_invalid_else".freeze))
       end
 
       block = ElseCondition.new

lib/liquid/tags/comment.rb

@@ -1,7 +1,7 @@
 module Liquid
   class Comment < Block
-    def render_to_output_buffer(_context, output)
+    def render(_context)
-      output
+      ''.freeze
     end
 
     def unknown_tag(_tag, _markup, _tokens)

lib/liquid/tags/cycle.rb

@@ -21,39 +21,28 @@ module Liquid
       super
       case markup
       when NamedSyntax
-        @variables = variables_from_string(Regexp.last_match(2))
+        @variables = variables_from_string($2)
-        @name = Expression.parse(Regexp.last_match(1))
+        @name = Expression.parse($1)
       when SimpleSyntax
         @variables = variables_from_string(markup)
         @name = @variables.to_s
       else
-        raise SyntaxError, options[:locale].t("errors.syntax.cycle".freeze)
+        raise SyntaxError.new(options[:locale].t("errors.syntax.cycle".freeze))
       end
     end
 
-    def render_to_output_buffer(context, output)
+    def render(context)
       context.registers[:cycle] ||= {}
 
       context.stack do
         key = context.evaluate(@name)
         iteration = context.registers[:cycle][key].to_i
-
+        result = context.evaluate(@variables[iteration])
-        val = context.evaluate(@variables[iteration])
-
-        if val.is_a?(Array)
-          val = val.join
-        elsif !val.is_a?(String)
-          val = val.to_s
-        end
-
-        output << val
-
         iteration += 1
         iteration  = 0 if iteration >= @variables.size
         context.registers[:cycle][key] = iteration
+        result
       end
-
-      output
     end
 
     private
@@ -61,7 +50,7 @@ module Liquid
     def variables_from_string(markup)
       markup.split(',').collect do |var|
         var =~ /\s*(#{QuotedFragment})\s*/o
-        Regexp.last_match(1) ? Expression.parse(Regexp.last_match(1)) : nil
+        $1 ? Expression.parse($1) : nil
       end.compact
     end
 

lib/liquid/tags/decrement.rb

@@ -23,12 +23,11 @@ module Liquid
       @variable = markup.strip
     end
 
-    def render_to_output_buffer(context, output)
+    def render(context)
       value = context.environments.first[@variable] ||= 0
       value -= 1
       context.environments.first[@variable] = value
-      output << value.to_s
+      value.to_s
-      output
     end
   end
 

lib/liquid/tags/echo.rb

@@ -1,24 +0,0 @@
-module Liquid
-  # Echo outputs an expression
-  #
-  #   {% echo monkey %}
-  #   {% echo user.name %}
-  #
-  # This is identical to variable output syntax, like {{ foo }}, but works
-  # inside {% liquid %} tags. The full syntax is supported, including filters:
-  #
-  #   {% echo user | link %}
-  #
-  class Echo < Tag
-    def initialize(tag_name, markup, parse_context)
-      super
-      @variable = Variable.new(markup, parse_context)
-    end
-
-    def render(context)
-      @variable.render_to_output_buffer(context, '')
-    end
-  end
-
-  Template.register_tag('echo'.freeze, Echo)
-end

lib/liquid/tags/for.rb

@@ -70,39 +70,37 @@ module Liquid
       @else_block = BlockBody.new
     end
 
-    def render_to_output_buffer(context, output)
+    def render(context)
       segment = collection_segment(context)
 
       if segment.empty?
-        render_else(context, output)
+        render_else(context)
       else
-        render_segment(context, output, segment)
+        render_segment(context, segment)
       end
-
-      output
     end
 
     protected
 
     def lax_parse(markup)
       if markup =~ Syntax
-        @variable_name = Regexp.last_match(1)
+        @variable_name = $1
-        collection_name = Regexp.last_match(2)
+        collection_name = $2
-        @reversed = !!Regexp.last_match(3)
+        @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, options[:locale].t("errors.syntax.for".freeze)
+        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, options[:locale].t("errors.syntax.for_invalid_in".freeze) unless p.id?('in'.freeze)
+      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)
@@ -110,7 +108,7 @@ module Liquid
 
       while p.look(:id) && p.look(:colon, 1)
         unless attribute = p.id?('limit'.freeze) || p.id?('offset'.freeze)
-          raise SyntaxError, options[:locale].t("errors.syntax.for_invalid_attribute".freeze)
+          raise SyntaxError.new(options[:locale].t("errors.syntax.for_invalid_attribute".freeze))
         end
         p.consume
         set_attribute(attribute, p.expression)
@@ -135,7 +133,6 @@ module Liquid
       end
 
       collection = context.evaluate(@collection_name)
-      collection = collection.to_a if collection.is_a?(Range)
 
       limit_value = context.evaluate(@limit)
       to = if limit_value.nil?
@@ -147,14 +144,16 @@ module Liquid
       segment = Utils.slice_collection(collection, from, to)
       segment.reverse! if @reversed
 
-      offsets[@name] = from + segment.length
+      offsets[@name] = from + segment.size
 
       segment
     end
 
-    def render_segment(context, output, segment)
+    def render_segment(context, segment)
       for_stack = context.registers[:for_stack] ||= []
-      length = segment.length
+      length = segment.size
+
+      result = ''
 
       context.stack do
         loop_vars = Liquid::ForloopDrop.new(@name, length, for_stack[-1])
@@ -166,21 +165,22 @@ module Liquid
 
           segment.each do |item|
             context[@variable_name] = item
-            @for_block.render_to_output_buffer(context, output)
+            result << @for_block.render(context)
             loop_vars.send(:increment!)
 
             # Handle any interrupts if they exist.
-            next unless context.interrupt?
+            if context.interrupt?
-            interrupt = context.pop_interrupt
+              interrupt = context.pop_interrupt
-            break if interrupt.is_a?(BreakInterrupt)
+              break if interrupt.is_a? BreakInterrupt
-            next if interrupt.is_a?(ContinueInterrupt)
+              next if interrupt.is_a? ContinueInterrupt
+            end
           end
         ensure
           for_stack.pop
         end
       end
 
-      output
+      result
     end
 
     def set_attribute(key, expr)
@@ -196,12 +196,8 @@ module Liquid
       end
     end
 
-    def render_else(context, output)
+    def render_else(context)
-      if @else_block
+      @else_block ? @else_block.render(context) : ''.freeze
-        @else_block.render_to_output_buffer(context, output)
-      else
-        output
-      end
     end
 
     class ParseTreeVisitor < Liquid::ParseTreeVisitor

lib/liquid/tags/if.rb

@@ -39,16 +39,15 @@ module Liquid
       end
     end
 
-    def render_to_output_buffer(context, output)
+    def render(context)
       context.stack do
         @blocks.each do |block|
           if block.evaluate(context)
-            return block.attachment.render_to_output_buffer(context, output)
+            return block.attachment.render(context)
           end
         end
+        ''.freeze
       end
-
-      output
     end
 
     private
@@ -66,17 +65,17 @@ module Liquid
 
     def lax_parse(markup)
       expressions = markup.scan(ExpressionsAndOperators)
-      raise SyntaxError, options[:locale].t("errors.syntax.if".freeze) unless expressions.pop =~ Syntax
+      raise(SyntaxError.new(options[:locale].t("errors.syntax.if".freeze))) unless expressions.pop =~ Syntax
 
-      condition = Condition.new(Expression.parse(Regexp.last_match(1)), Regexp.last_match(2), Expression.parse(Regexp.last_match(3)))
+      condition = Condition.new(Expression.parse($1), $2, Expression.parse($3))
 
       until expressions.empty?
         operator = expressions.pop.to_s.strip
 
-        raise SyntaxError, options[:locale].t("errors.syntax.if".freeze) unless expressions.pop.to_s =~ Syntax
+        raise(SyntaxError.new(options[:locale].t("errors.syntax.if".freeze))) unless expressions.pop.to_s =~ Syntax
 
-        new_condition = Condition.new(Expression.parse(Regexp.last_match(1)), Regexp.last_match(2), Expression.parse(Regexp.last_match(3)))
+        new_condition = Condition.new(Expression.parse($1), $2, Expression.parse($3))
-        raise SyntaxError, options[:locale].t("errors.syntax.if".freeze) unless BOOLEAN_OPERATORS.include?(operator)
+        raise(SyntaxError.new(options[:locale].t("errors.syntax.if".freeze))) unless BOOLEAN_OPERATORS.include?(operator)
         new_condition.send(operator, condition)
         condition = new_condition
       end

lib/liquid/tags/ifchanged.rb

@@ -1,17 +1,16 @@
 module Liquid
   class Ifchanged < Block
-    def render_to_output_buffer(context, output)
+    def render(context)
       context.stack do
-        block_output = ''
+        output = super
-        super(context, block_output)
 
-        if block_output != context.registers[:ifchanged]
+        if output != context.registers[:ifchanged]
-          context.registers[:ifchanged] = block_output
+          context.registers[:ifchanged] = output
-          output << block_output
+          output
+        else
+          ''.freeze
         end
       end
-
-      output
     end
   end
 

lib/liquid/tags/include.rb

@@ -23,8 +23,8 @@ module Liquid
 
       if markup =~ Syntax
 
-        template_name = Regexp.last_match(1)
+        template_name = $1
-        variable_name = Regexp.last_match(3)
+        variable_name = $3
 
         @variable_name_expr = variable_name ? Expression.parse(variable_name) : nil
         @template_name_expr = Expression.parse(template_name)
@@ -35,23 +35,18 @@ module Liquid
         end
 
       else
-        raise SyntaxError, options[:locale].t("errors.syntax.include".freeze)
+        raise SyntaxError.new(options[:locale].t("errors.syntax.include".freeze))
       end
     end
 
     def parse(_tokens)
     end
 
-    def render_to_output_buffer(context, output)
+    def render(context)
       template_name = context.evaluate(@template_name_expr)
-      raise ArgumentError, options[:locale].t("errors.argument.include") unless template_name
+      raise ArgumentError.new(options[:locale].t("errors.argument.include")) unless template_name
-
-      partial = PartialCache.load(
-        template_name,
-        context: context,
-        parse_context: parse_context
-      )
 
+      partial = load_cached_partial(template_name, context)
       context_variable_name = template_name.split('/'.freeze).last
 
       variable = if @variable_name_expr
@@ -71,31 +66,55 @@ module Liquid
           end
 
           if variable.is_a?(Array)
-            variable.each do |var|
+            variable.collect do |var|
               context[context_variable_name] = var
-              partial.render_to_output_buffer(context, output)
+              partial.render(context)
             end
           else
             context[context_variable_name] = variable
-            partial.render_to_output_buffer(context, output)
+            partial.render(context)
           end
         end
       ensure
         context.template_name = old_template_name
         context.partial = old_partial
       end
-
-      output
     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.variable_name_expr
         ] + @node.attributes.values
       end
     end

lib/liquid/tags/increment.rb

@@ -20,12 +20,10 @@ module Liquid
       @variable = markup.strip
     end
 
-    def render_to_output_buffer(context, output)
+    def render(context)
       value = context.environments.first[@variable] ||= 0
       context.environments.first[@variable] = value + 1
-
+      value.to_s
-      output << value.to_s
-      output
     end
   end
 

lib/liquid/tags/raw.rb

@@ -13,18 +13,17 @@ module Liquid
       @body = ''
       while token = tokens.shift
         if token =~ FullTokenPossiblyInvalid
-          @body << Regexp.last_match(1) if Regexp.last_match(1) != "".freeze
+          @body << $1 if $1 != "".freeze
-          return if block_delimiter == Regexp.last_match(2)
+          return if block_delimiter == $2
         end
         @body << token unless token.empty?
       end
 
-      raise SyntaxError, parse_context.locale.t("errors.syntax.tag_never_closed".freeze, block_name: block_name)
+      raise SyntaxError.new(parse_context.locale.t("errors.syntax.tag_never_closed".freeze, block_name: block_name))
     end
 
-    def render_to_output_buffer(_context, output)
+    def render(_context)
-      output << @body
+      @body
-      output
     end
 
     def nodelist
@@ -39,7 +38,7 @@ module Liquid
 
     def ensure_valid_markup(tag_name, markup, parse_context)
       unless markup =~ Syntax
-        raise SyntaxError, parse_context.locale.t("errors.syntax.tag_unexpected_args".freeze, tag: tag_name)
+        raise SyntaxError.new(parse_context.locale.t("errors.syntax.tag_unexpected_args".freeze, tag: tag_name))
       end
     end
   end

lib/liquid/tags/render.rb

@@ -1,54 +0,0 @@
-module Liquid
-  class Render < Tag
-    SYNTAX = /(#{QuotedString})#{QuotedFragment}*/o
-
-    attr_reader :template_name_expr, :attributes
-
-    def initialize(tag_name, markup, options)
-      super
-
-      raise SyntaxError, options[:locale].t("errors.syntax.render".freeze) unless markup =~ SYNTAX
-
-      template_name = Regexp.last_match(1)
-
-      @template_name_expr = Expression.parse(template_name)
-
-      @attributes = {}
-      markup.scan(TagAttributes) do |key, value|
-        @attributes[key] = Expression.parse(value)
-      end
-    end
-
-    def render_to_output_buffer(context, output)
-      # Though we evaluate this here we will only ever parse it as a string literal.
-      template_name = context.evaluate(@template_name_expr)
-      raise ArgumentError, options[:locale].t("errors.argument.include") unless template_name
-
-      partial = PartialCache.load(
-        template_name,
-        context: context,
-        parse_context: parse_context
-      )
-
-      inner_context = context.new_isolated_subcontext
-      inner_context.template_name = template_name
-      inner_context.partial = true
-      @attributes.each do |key, value|
-        inner_context[key] = context.evaluate(value)
-      end
-      partial.render_to_output_buffer(inner_context, output)
-
-      output
-    end
-
-    class ParseTreeVisitor < Liquid::ParseTreeVisitor
-      def children
-        [
-          @node.template_name_expr,
-        ] + @node.attributes.values
-      end
-    end
-  end
-
-  Template.register_tag('render'.freeze, Render)
-end

lib/liquid/tags/table_row.rb

@@ -7,19 +7,19 @@ module Liquid
     def initialize(tag_name, markup, options)
       super
       if markup =~ Syntax
-        @variable_name = Regexp.last_match(1)
+        @variable_name = $1
-        @collection_name = Expression.parse(Regexp.last_match(2))
+        @collection_name = Expression.parse($2)
         @attributes = {}
         markup.scan(TagAttributes) do |key, value|
           @attributes[key] = Expression.parse(value)
         end
       else
-        raise SyntaxError, options[:locale].t("errors.syntax.table_row".freeze)
+        raise SyntaxError.new(options[:locale].t("errors.syntax.table_row".freeze))
       end
     end
 
-    def render_to_output_buffer(context, output)
+    def render(context)
-      (collection = context.evaluate(@collection_name)) || (return ''.freeze)
+      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
@@ -30,7 +30,7 @@ module Liquid
 
       cols = context.evaluate(@attributes['cols'.freeze]).to_i
 
-      output << "<tr class=\"row1\">\n"
+      result = "<tr class=\"row1\">\n"
       context.stack do
         tablerowloop = Liquid::TablerowloopDrop.new(length, cols)
         context['tablerowloop'.freeze] = tablerowloop
@@ -38,20 +38,17 @@ module Liquid
         collection.each do |item|
           context[@variable_name] = item
 
-          output << "<td class=\"col#{tablerowloop.col}\">"
+          result << "<td class=\"col#{tablerowloop.col}\">" << super << '</td>'
-          super
-          output << '</td>'
 
           if tablerowloop.col_last && !tablerowloop.last
-            output << "</tr>\n<tr class=\"row#{tablerowloop.row + 1}\">"
+            result << "</tr>\n<tr class=\"row#{tablerowloop.row + 1}\">"
           end
 
           tablerowloop.send(:increment!)
         end
       end
-
+      result << "</tr>\n"
-      output << "</tr>\n"
+      result
-      output
     end
 
     class ParseTreeVisitor < Liquid::ParseTreeVisitor

lib/liquid/tags/unless.rb

@@ -6,23 +6,23 @@ module Liquid
   #   {% unless x < 0 %} x is greater than zero {% endunless %}
   #
   class Unless < If
-    def render_to_output_buffer(context, output)
+    def render(context)
       context.stack do
         # First condition is interpreted backwards ( if not )
         first_block = @blocks.first
         unless first_block.evaluate(context)
-          return first_block.attachment.render_to_output_buffer(context, output)
+          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 block.attachment.render_to_output_buffer(context, output)
+            return block.attachment.render(context)
           end
         end
-      end
 
-      output
+        ''.freeze
+      end
     end
   end
 

lib/liquid/template.rb

@@ -50,7 +50,7 @@ module Liquid
       private
 
       def lookup_class(name)
-        Object.const_get(name)
+        name.split("::").reject(&:empty?).reduce(Object) { |scope, const| scope.const_get(const) }
       end
     end
 
@@ -172,7 +172,7 @@ module Liquid
         c = args.shift
 
         if @rethrow_errors
-          c.exception_renderer = ->(_e) { raise }
+          c.exception_renderer = ->(e) { raise }
         end
 
         c
@@ -187,12 +187,9 @@ module Liquid
         raise ArgumentError, "Expected Hash or Liquid::Context as parameter"
       end
 
-      output = nil
-
       case args.last
       when Hash
         options = args.pop
-        output = options[:output] if options[:output]
 
         registers.merge!(options[:registers]) if options[:registers].is_a?(Hash)
 
@@ -207,9 +204,10 @@ module Liquid
       begin
         # render the nodelist.
         # for performance reasons we get an array back here. join will make a string out of it.
-        with_profiling(context) do
+        result = with_profiling(context) do
-          @root.render_to_output_buffer(context, output || '')
+          @root.render(context)
         end
+        result.respond_to?(:join) ? result.join : result
       rescue Liquid::MemoryError => e
         context.handle_error(e)
       ensure
@@ -222,10 +220,6 @@ module Liquid
       render(*args)
     end
 
-    def render_to_output_buffer(context, output)
-      render(context, output: output)
-    end
-
     private
 
     def tokenize(source)

lib/liquid/tokenizer.rb

@@ -1,35 +1,29 @@
 module Liquid
   class Tokenizer
-    attr_reader :line_number, :for_liquid_tag
+    attr_reader :line_number
 
-    def initialize(source, line_numbers = false, line_number: nil, for_liquid_tag: false)
+    def initialize(source, line_numbers = false)
       @source = source
-      @line_number = line_number || (line_numbers ? 1 : nil)
+      @line_number = line_numbers ? 1 : nil
-      @for_liquid_tag = for_liquid_tag
       @tokens = tokenize
     end
 
     def shift
-      (token = @tokens.shift) || return
+      token = @tokens.shift
-
+      @line_number += token.count("\n") if @line_number && token
-      if @line_number
-        @line_number += @for_liquid_tag ? 1 : token.count("\n")
-      end
-
       token
     end
 
     private
 
     def tokenize
+      @source = @source.source if @source.respond_to?(:source)
       return [] if @source.to_s.empty?
 
-      return @source.split("\n") if @for_liquid_tag
-
       tokens = @source.split(TemplateParser)
 
       # removes the rogue empty element at the beginning of the array
-      tokens.shift if tokens[0]&.empty?
+      tokens.shift if tokens[0] && tokens[0].empty?
 
       tokens
     end

lib/liquid/utils.rb

@@ -1,6 +1,8 @@
 module Liquid
   module Utils
     def self.slice_collection(collection, from, to)
+      return collection.load_slice(from, to) if collection.is_a?(ReversableRange)
+
       if (from != 0 || !to.nil?) && collection.respond_to?(:load_slice)
         collection.load_slice(from, to)
       else
@@ -50,7 +52,7 @@ module Liquid
       when Numeric
         obj
       when String
-        obj.strip =~ /\A-?\d+\.\d+\z/ ? BigDecimal(obj) : obj.to_i
+        (obj.strip =~ /\A-?\d+\.\d+\z/) ? BigDecimal(obj) : obj.to_i
       else
         if obj.respond_to?(:to_number)
           obj.to_number

lib/liquid/variable.rb

@@ -43,11 +43,11 @@ module Liquid
       @filters = []
       return unless markup =~ MarkupWithQuotedFragment
 
-      name_markup = Regexp.last_match(1)
+      name_markup = $1
-      filter_markup = Regexp.last_match(2)
+      filter_markup = $2
       @name = Expression.parse(name_markup)
       if filter_markup =~ FilterMarkupRegex
-        filters = Regexp.last_match(1).scan(FilterParser)
+        filters = $1.scan(FilterParser)
         filters.each do |f|
           next unless f =~ /\w+/
           filtername = Regexp.last_match(0)
@@ -85,23 +85,12 @@ module Liquid
       end
 
       obj = context.apply_global_filter(obj)
+
       taint_check(context, obj)
+
       obj
     end
 
-    def render_to_output_buffer(context, output)
-      obj = render(context)
-
-      if obj.is_a?(Array)
-        output << obj.join
-      elsif obj.nil?
-      else
-        output << obj.to_s
-      end
-
-      output
-    end
-
     private
 
     def parse_filter_expressions(filter_name, unparsed_args)
@@ -121,7 +110,7 @@ module Liquid
     end
 
     def evaluate_filter_expressions(context, filter_args, filter_kwargs)
-      parsed_args = filter_args.map { |expr| context.evaluate(expr) }
+      parsed_args = filter_args.map{ |expr| context.evaluate(expr) }
       if filter_kwargs
         parsed_kwargs = {}
         filter_kwargs.each do |key, expr|

lib/liquid/variable_lookup.rb

@@ -14,7 +14,7 @@ module Liquid
 
       name = lookups.shift
       if name =~ SQUARE_BRACKETED
-        name = Expression.parse(Regexp.last_match(1))
+        name = Expression.parse($1)
       end
       @name = name
 
@@ -24,7 +24,7 @@ module Liquid
       @lookups.each_index do |i|
         lookup = lookups[i]
         if lookup =~ SQUARE_BRACKETED
-          lookups[i] = Expression.parse(Regexp.last_match(1))
+          lookups[i] = Expression.parse($1)
         elsif COMMAND_METHODS.include?(lookup)
           @command_flags |= 1 << i
         end

liquid.gemspec

@@ -1,7 +1,7 @@
 # encoding: utf-8
 
 lib = File.expand_path('../lib/', __FILE__)
-$LOAD_PATH.unshift(lib) unless $LOAD_PATH.include?(lib)
+$LOAD_PATH.unshift lib unless $LOAD_PATH.include?(lib)
 
 require "liquid/version"
 
@@ -16,7 +16,7 @@ Gem::Specification.new do |s|
   s.license     = "MIT"
   # s.description = "A secure, non-evaling end user template engine with aesthetic markup."
 
-  s.required_ruby_version     = ">= 2.4.0"
+  s.required_ruby_version     = ">= 2.1.0"
   s.required_rubygems_version = ">= 1.3.7"
 
   s.test_files  = Dir.glob("{test}/**/*")
@@ -26,6 +26,6 @@ Gem::Specification.new do |s|
 
   s.require_path = "lib"
 
-  s.add_development_dependency('rake', '~> 11.3')
+  s.add_development_dependency 'rake', '~> 11.3'
-  s.add_development_dependency('minitest')
+  s.add_development_dependency 'minitest'
 end

performance/memory_profile.rb

@@ -2,62 +2,25 @@
 
 require 'benchmark/ips'
 require 'memory_profiler'
-require 'terminal-table'
 require_relative 'theme_runner'
 
-class Profiler
+def profile(phase, &block)
-  LOG_LABEL   = "Profiling: ".rjust(14).freeze
+  puts
-  REPORTS_DIR = File.expand_path('.memprof', __dir__).freeze
+  puts "#{phase}:"
+  puts
 
-  def self.run
+  report = MemoryProfiler.report(&block)
-    puts
-    yield new
-  end
 
-  def initialize
+  report.pretty_print(
-    @allocated = []
+    color_output: true,
-    @retained  = []
+    scale_bytes: true,
-    @headings  = []
+    detailed_report: true
-  end
+  )
-
-  def profile(phase, &block)
-    print LOG_LABEL
-    print "#{phase}.. ".ljust(10)
-    report = MemoryProfiler.report(&block)
-    puts 'Done.'
-    @headings  << phase.capitalize
-    @allocated << "#{report.scale_bytes(report.total_allocated_memsize)} (#{report.total_allocated} objects)"
-    @retained  << "#{report.scale_bytes(report.total_retained_memsize)} (#{report.total_retained} objects)"
-
-    return if ENV['CI']
-
-    require 'fileutils'
-    report_file = File.join(REPORTS_DIR, "#{sanitize(phase)}.txt")
-    FileUtils.mkdir_p(REPORTS_DIR)
-    report.pretty_print(to_file: report_file, scale_bytes: true)
-  end
-
-  def tabulate
-    table = Terminal::Table.new(headings: @headings.unshift('Phase')) do |t|
-      t << @allocated.unshift('Total allocated')
-      t << @retained.unshift('Total retained')
-    end
-
-    puts
-    puts table
-    puts "\nDetailed report(s) saved to #{REPORTS_DIR}/" unless ENV['CI']
-  end
-
-  def sanitize(string)
-    string.downcase.gsub(/[\W]/, '-').squeeze('-')
-  end
 end
 
 Liquid::Template.error_mode = ARGV.first.to_sym if ARGV.first
 
-runner = ThemeRunner.new
+profiler = ThemeRunner.new
-Profiler.run do |x|
+
-  x.profile('parse') { runner.compile }
+profile("Parsing") { profiler.compile }
-  x.profile('render') { runner.render }
+profile("Rendering") { profiler.render }
-  x.tabulate
-end

performance/shopify/comment_form.rb

@@ -5,14 +5,14 @@ class CommentForm < Liquid::Block
     super
 
     if markup =~ Syntax
-      @variable_name = Regexp.last_match(1)
+      @variable_name = $1
       @attributes = {}
     else
-      raise SyntaxError, "Syntax Error in 'comment_form' - Valid syntax: comment_form [article]"
+      raise SyntaxError.new("Syntax Error in 'comment_form' - Valid syntax: comment_form [article]")
     end
   end
 
-  def render_to_output_buffer(context, output)
+  def render(context)
     article = context[@variable_name]
 
     context.stack do
@@ -20,12 +20,10 @@ class CommentForm < Liquid::Block
         'posted_successfully?' => context.registers[:posted_successfully],
         'errors' => context['comment.errors'],
         'author' => context['comment.author'],
-        'email' => context['comment.email'],
+        'email'  => context['comment.email'],
-        'body' => context['comment.body'],
+        'body'   => context['comment.body']
       }
-
+      wrap_in_form(article, render_all(@nodelist, context))
-      output << wrap_in_form(article, render_all(@nodelist, context, output))
-      output
     end
   end
 

performance/shopify/database.rb

@@ -16,10 +16,9 @@ module Database
       end
 
       # key the tables by handles, as this is how liquid expects it.
-      db = db.each_with_object({}) do |(key, values), assigns|
+      db = db.inject({}) do |assigns, (key, values)|
-        assigns[key] = values.each_with_object({}) do |v, h|
+        assigns[key] = values.inject({}) { |h, v| h[v['handle']] = v; h; }
-          h[v['handle']] = v
+        assigns
-        end
       end
 
       # Some standard direct accessors so that the specialized templates
@@ -31,8 +30,8 @@ module Database
 
       db['cart']       = {
         'total_price' => db['line_items'].values.inject(0) { |sum, item| sum += item['line_price'] * item['quantity'] },
-        'item_count' => db['line_items'].values.inject(0) { |sum, item| sum += item['quantity'] },
+        'item_count'  => db['line_items'].values.inject(0) { |sum, item| sum += item['quantity'] },
-        'items' => db['line_items'].values,
+        'items'       => db['line_items'].values
       }
 
       db
@@ -41,6 +40,6 @@ module Database
 end
 
 if __FILE__ == $PROGRAM_NAME
-  p(Database.tables['collections']['frontpage'].keys)
+  p Database.tables['collections']['frontpage'].keys
   # p Database.tables['blog']['articles']
 end

performance/shopify/json_filter.rb

@@ -2,6 +2,6 @@ require 'json'
 
 module JsonFilter
   def json(object)
-    JSON.dump(object.reject { |k, _v| k == "collections" })
+    JSON.dump(object.reject { |k, v| k == "collections" })
   end
 end

performance/shopify/liquid.rb

@@ -1,4 +1,4 @@
-$LOAD_PATH.unshift(__dir__ + '/../../lib')
+$:.unshift __dir__ + '/../../lib'
 require_relative '../../lib/liquid'
 
 require_relative 'comment_form'
@@ -9,11 +9,11 @@ require_relative 'shop_filter'
 require_relative 'tag_filter'
 require_relative 'weight_filter'
 
-Liquid::Template.register_tag('paginate', Paginate)
+Liquid::Template.register_tag 'paginate', Paginate
-Liquid::Template.register_tag('form', CommentForm)
+Liquid::Template.register_tag 'form', CommentForm
 
-Liquid::Template.register_filter(JsonFilter)
+Liquid::Template.register_filter JsonFilter
-Liquid::Template.register_filter(MoneyFilter)
+Liquid::Template.register_filter MoneyFilter
-Liquid::Template.register_filter(WeightFilter)
+Liquid::Template.register_filter WeightFilter
-Liquid::Template.register_filter(ShopFilter)
+Liquid::Template.register_filter ShopFilter
-Liquid::Template.register_filter(TagFilter)
+Liquid::Template.register_filter TagFilter

performance/shopify/money_filter.rb

@@ -1,12 +1,12 @@
 module MoneyFilter
   def money_with_currency(money)
     return '' if money.nil?
-    format("$ %.2f USD", money / 100.0)
+    sprintf("$ %.2f USD", money / 100.0)
   end
 
   def money(money)
     return '' if money.nil?
-    format("$ %.2f", money / 100.0)
+    sprintf("$ %.2f", money / 100.0)
   end
 
   private

performance/shopify/paginate.rb

@@ -1,13 +1,13 @@
 class Paginate < Liquid::Block
-  Syntax = /(#{Liquid::QuotedFragment})\s*(by\s*(\d+))?/
+  Syntax     = /(#{Liquid::QuotedFragment})\s*(by\s*(\d+))?/
 
   def initialize(tag_name, markup, options)
     super
 
     if markup =~ Syntax
-      @collection_name = Regexp.last_match(1)
+      @collection_name = $1
-      @page_size = if Regexp.last_match(2)
+      @page_size = if $2
-        Regexp.last_match(3).to_i
+        $3.to_i
       else
         20
       end
@@ -17,27 +17,27 @@ class Paginate < Liquid::Block
         @attributes[key] = value
       end
     else
-      raise SyntaxError, "Syntax Error in tag 'paginate' - Valid syntax: paginate [collection] by number"
+      raise SyntaxError.new("Syntax Error in tag 'paginate' - Valid syntax: paginate [collection] by number")
     end
   end
 
-  def render_to_output_buffer(context, output)
+  def render(context)
     @context = context
 
     context.stack do
-      current_page = context['current_page'].to_i
+      current_page  = context['current_page'].to_i
 
       pagination = {
-        'page_size' => @page_size,
+        'page_size'      => @page_size,
-        'current_page' => 5,
+        'current_page'   => 5,
-        'current_offset' => @page_size * 5,
+        'current_offset' => @page_size * 5
       }
 
       context['paginate'] = pagination
 
-      collection_size = context[@collection_name].size
+      collection_size  = context[@collection_name].size
 
-      raise ArgumentError, "Cannot paginate array '#{@collection_name}'. Not found." if collection_size.nil?
+      raise ArgumentError.new("Cannot paginate array '#{@collection_name}'. Not found.") if collection_size.nil?
 
       page_count = (collection_size.to_f / @page_size.to_f).to_f.ceil + 1
 

performance/shopify/shop_filter.rb

@@ -52,7 +52,7 @@ module ShopFilter
   end
 
   def product_img_url(url, style = 'small')
-    unless url =~ %r{\Aproducts/([\w\-\_]+)\.(\w{2,4})}
+    unless url =~ /\Aproducts\/([\w\-\_]+)\.(\w{2,4})/
       raise ArgumentError, 'filter "size" can only be called on product images'
     end
 
@@ -60,7 +60,7 @@ module ShopFilter
     when 'original'
       return '/files/shops/random_number/' + url
     when 'grande', 'large', 'medium', 'compact', 'small', 'thumb', 'icon'
-      "/files/shops/random_number/products/#{Regexp.last_match(1)}_#{style}.#{Regexp.last_match(2)}"
+      "/files/shops/random_number/products/#{$1}_#{style}.#{$2}"
     else
       raise ArgumentError, 'valid parameters for filter "size" are: original, grande, large, medium, compact, small, thumb and icon '
     end
@@ -70,14 +70,16 @@ module ShopFilter
     html = []
     html << %(<span class="prev">#{link_to(paginate['previous']['title'], paginate['previous']['url'])}</span>) if paginate['previous']
 
-    paginate['parts'].each do |part|
+    for part in paginate['parts']
-      html << if part['is_link']
+
-        %(<span class="page">#{link_to(part['title'], part['url'])}</span>)
+      if part['is_link']
+        html << %(<span class="page">#{link_to(part['title'], part['url'])}</span>)
       elsif part['title'].to_i == paginate['current_page'].to_i
-        %(<span class="page current">#{part['title']}</span>)
+        html << %(<span class="page current">#{part['title']}</span>)
       else
-        %(<span class="deco">#{part['title']}</span>)
+        html << %(<span class="deco">#{part['title']}</span>)
       end
+
     end
 
     html << %(<span class="next">#{link_to(paginate['next']['title'], paginate['next']['url'])}</span>) if paginate['next']

performance/shopify/tag_filter.rb

@@ -13,11 +13,11 @@ module TagFilter
 
   def link_to_add_tag(label, tag)
     tags = (@context['current_tags'] + [tag]).uniq
-    "<a title=\"Show tag #{tag}\" href=\"/collections/#{@context['handle']}/#{tags.join('+')}\">#{label}</a>"
+    "<a title=\"Show tag #{tag}\" href=\"/collections/#{@context['handle']}/#{tags.join("+")}\">#{label}</a>"
   end
 
   def link_to_remove_tag(label, tag)
     tags = (@context['current_tags'] - [tag]).uniq
-    "<a title=\"Show tag #{tag}\" href=\"/collections/#{@context['handle']}/#{tags.join('+')}\">#{label}</a>"
+    "<a title=\"Show tag #{tag}\" href=\"/collections/#{@context['handle']}/#{tags.join("+")}\">#{label}</a>"
   end
 end

performance/shopify/weight_filter.rb

@@ -1,6 +1,6 @@
 module WeightFilter
   def weight(grams)
-    format("%.2f", grams / 1000)
+    sprintf("%.2f", grams / 1000)
   end
 
   def weight_with_unit(grams)

performance/theme_runner.rb

@@ -31,7 +31,7 @@ class ThemeRunner
       {
         liquid: File.read(test),
         layout: (File.file?(theme_path) ? File.read(theme_path) : nil),
-        template_name: test,
+        template_name: test
       }
     end.compact
 

test/integration/blank_test.rb

@@ -1,10 +1,11 @@
 require 'test_helper'
 
 class FoobarTag < Liquid::Tag
-  def render_to_output_buffer(_context, output)
+  def render(*args)
-    output << ' '
+    " "
-    output
   end
+
+  Liquid::Template.register_tag('foobar', FoobarTag)
 end
 
 class BlankTestFileSystem
@@ -30,9 +31,7 @@ class BlankTest < Minitest::Test
   end
 
   def test_new_tags_are_not_blank_by_default
-    with_custom_tag('foobar', FoobarTag) do
+    assert_template_result(" " * N, wrap_in_for("{% foobar %}"))
-      assert_template_result(" " * N, wrap_in_for("{% foobar %}"))
-    end
   end
 
   def test_loops_are_blank

test/integration/drop_test.rb

@@ -201,9 +201,9 @@ class DropsTest < Minitest::Test
   end
 
   def test_scope_though_proc
-    assert_equal '1', Liquid::Template.parse('{{ s }}').render!('context' => ContextDrop.new, 's' => proc { |c| c['context.scopes'] })
+    assert_equal '1', Liquid::Template.parse('{{ s }}').render!('context' => ContextDrop.new, 's' => proc{ |c| c['context.scopes'] })
-    assert_equal '2', Liquid::Template.parse('{%for i in dummy%}{{ s }}{%endfor%}').render!('context' => ContextDrop.new, 's' => proc { |c| c['context.scopes'] }, 'dummy' => [1])
+    assert_equal '2', Liquid::Template.parse('{%for i in dummy%}{{ s }}{%endfor%}').render!('context' => ContextDrop.new, 's' => proc{ |c| c['context.scopes'] }, 'dummy' => [1])
-    assert_equal '3', Liquid::Template.parse('{%for i in dummy%}{%for i in dummy%}{{ s }}{%endfor%}{%endfor%}').render!('context' => ContextDrop.new, 's' => proc { |c| c['context.scopes'] }, 'dummy' => [1])
+    assert_equal '3', Liquid::Template.parse('{%for i in dummy%}{%for i in dummy%}{{ s }}{%endfor%}{%endfor%}').render!('context' => ContextDrop.new, 's' => proc{ |c| c['context.scopes'] }, 'dummy' => [1])
   end
 
   def test_scope_with_assigns
@@ -241,7 +241,7 @@ class DropsTest < Minitest::Test
   end
 
   def test_some_enumerable_methods_still_get_invoked
-    [:count, :max].each do |method|
+    [ :count, :max ].each do |method|
       assert_equal "3", Liquid::Template.parse("{{collection.#{method}}}").render!('collection' => RealEnumerableDrop.new)
       assert_equal "3", Liquid::Template.parse("{{collection[\"#{method}\"]}}").render!('collection' => RealEnumerableDrop.new)
       assert_equal "3", Liquid::Template.parse("{{collection.#{method}}}").render!('collection' => EnumerableDrop.new)
@@ -250,7 +250,7 @@ class DropsTest < Minitest::Test
 
     assert_equal "yes", Liquid::Template.parse("{% if collection contains 3 %}yes{% endif %}").render!('collection' => RealEnumerableDrop.new)
 
-    [:min, :first].each do |method|
+    [ :min, :first ].each do |method|
       assert_equal "1", Liquid::Template.parse("{{collection.#{method}}}").render!('collection' => RealEnumerableDrop.new)
       assert_equal "1", Liquid::Template.parse("{{collection[\"#{method}\"]}}").render!('collection' => RealEnumerableDrop.new)
       assert_equal "1", Liquid::Template.parse("{{collection.#{method}}}").render!('collection' => EnumerableDrop.new)

test/integration/error_handling_test.rb

@@ -83,14 +83,15 @@ class ErrorHandlingTest < Minitest::Test
 
   def test_with_line_numbers_adds_numbers_to_parser_errors
     err = assert_raises(SyntaxError) do
-      Liquid::Template.parse('
+      Liquid::Template.parse(%q(
           foobar
 
           {% "cat" | foobar %}
 
           bla
-        ',
+        ),
-        line_numbers: true)
+        line_numbers: true
+      )
     end
 
     assert_match(/Liquid syntax error \(line 4\)/, err.message)
@@ -98,14 +99,15 @@ class ErrorHandlingTest < Minitest::Test
 
   def test_with_line_numbers_adds_numbers_to_parser_errors_with_whitespace_trim
     err = assert_raises(SyntaxError) do
-      Liquid::Template.parse('
+      Liquid::Template.parse(%q(
           foobar
 
           {%- "cat" | foobar -%}
 
           bla
-        ',
+        ),
-        line_numbers: true)
+        line_numbers: true
+      )
     end
 
     assert_match(/Liquid syntax error \(line 4\)/, err.message)
@@ -120,7 +122,8 @@ class ErrorHandlingTest < Minitest::Test
         bla
             ',
       error_mode: :warn,
-      line_numbers: true)
+      line_numbers: true
+    )
 
     assert_equal ['Liquid syntax error (line 4): Unexpected character = in "1 =! 2"'],
       template.warnings.map(&:message)
@@ -136,7 +139,8 @@ class ErrorHandlingTest < Minitest::Test
           bla
                 ',
         error_mode: :strict,
-        line_numbers: true)
+        line_numbers: true
+      )
     end
 
     assert_equal 'Liquid syntax error (line 4): Unexpected character = in "1 =! 2"', err.message
@@ -153,7 +157,8 @@ class ErrorHandlingTest < Minitest::Test
 
           bla
                 ',
-        line_numbers: true)
+        line_numbers: true
+      )
     end
 
     assert_equal "Liquid syntax error (line 5): Unknown tag 'foo'", err.message
@@ -200,7 +205,7 @@ class ErrorHandlingTest < Minitest::Test
   def test_default_exception_renderer_with_internal_error
     template = Liquid::Template.parse('This is a runtime error: {{ errors.runtime_error }}', line_numbers: true)
 
-    output = template.render('errors' => ErrorDrop.new)
+    output = template.render({ 'errors' => ErrorDrop.new })
 
     assert_equal 'This is a runtime error: Liquid error (line 1): internal', output
     assert_equal [Liquid::InternalError], template.errors.map(&:class)
@@ -212,7 +217,7 @@ class ErrorHandlingTest < Minitest::Test
     Liquid::Template.default_exception_renderer = ->(e) { exceptions << e; '' }
     template = Liquid::Template.parse('This is a runtime error: {{ errors.argument_error }}')
 
-    output = template.render('errors' => ErrorDrop.new)
+    output = template.render({ 'errors' => ErrorDrop.new })
 
     assert_equal 'This is a runtime error: ', output
     assert_equal [Liquid::ArgumentError], template.errors.map(&:class)
@@ -234,7 +239,7 @@ class ErrorHandlingTest < Minitest::Test
   end
 
   class TestFileSystem
-    def read_template_file(_template_path)
+    def read_template_file(template_path)
       "{{ errors.argument_error }}"
     end
   end

test/integration/filter_test.rb

@@ -2,23 +2,23 @@ require 'test_helper'
 
 module MoneyFilter
   def money(input)
-    format(' %d$ ', input)
+    sprintf(' %d$ ', input)
   end
 
   def money_with_underscore(input)
-    format(' %d$ ', input)
+    sprintf(' %d$ ', input)
   end
 end
 
 module CanadianMoneyFilter
   def money(input)
-    format(' %d$ CAD ', input)
+    sprintf(' %d$ CAD ', input)
   end
 end
 
 module SubstituteFilter
   def substitute(input, params = {})
-    input.gsub(/%\{(\w+)\}/) { |_match| params[Regexp.last_match(1)] }
+    input.gsub(/%\{(\w+)\}/) { |match| params[$1] }
   end
 end
 
@@ -26,7 +26,7 @@ class FiltersTest < Minitest::Test
   include Liquid
 
   module OverrideObjectMethodFilter
-    def tap(_input)
+    def tap(input)
       "tap overridden"
     end
   end
@@ -149,7 +149,7 @@ class FiltersTest < Minitest::Test
     assert_equal "tap overridden", Template.parse("{{var | tap}}").render!({ 'var' => 1000 }, filters: [OverrideObjectMethodFilter])
 
     # tap still treated as a non-existent filter
-    assert_equal "1000", Template.parse("{{var | tap}}").render!('var' => 1000)
+    assert_equal "1000", Template.parse("{{var | tap}}").render!({ 'var' => 1000 })
   end
 end
 

test/integration/hash_ordering_test.rb

@@ -3,13 +3,13 @@ require 'test_helper'
 class HashOrderingTest < Minitest::Test
   module MoneyFilter
     def money(input)
-      format(' %d$ ', input)
+      sprintf(' %d$ ', input)
     end
   end
 
   module CanadianMoneyFilter
     def money(input)
-      format(' %d$ CAD ', input)
+      sprintf(' %d$ CAD ', input)
     end
   end
 

test/integration/output_test.rb

@@ -1,7 +1,7 @@
 require 'test_helper'
 
 module FunnyFilter
-  def make_funny(_input)
+  def make_funny(input)
     'LOL'
   end
 
@@ -32,7 +32,7 @@ class OutputTest < Minitest::Test
   def setup
     @assigns = {
       'best_cars' => 'bmw',
-      'car' => { 'bmw' => 'good', 'gm' => 'bad' },
+      'car' => { 'bmw' => 'good', 'gm' => 'bad' }
     }
   end
 

test/integration/parse_tree_visitor_test.rb

@@ -227,7 +227,7 @@ class ParseTreeVisitorTest < Minitest::Test
       [[nil, [
         [nil, [[nil, [["other", []]]]]],
         ["test", []],
-        ["xs", []],
+        ["xs", []]
       ]]],
       traversal(%({% for x in xs offset: test %}{{ other }}{% endfor %})).visit
     )

test/integration/render_profiling_test.rb

@@ -128,7 +128,7 @@ class RenderProfilingTest < Minitest::Test
     t.render!
 
     timing_count = 0
-    t.profiler.each do |_timing|
+    t.profiler.each do |timing|
       timing_count += 1
     end
 
@@ -145,7 +145,7 @@ class RenderProfilingTest < Minitest::Test
 
   def test_profiling_marks_children_of_for_blocks
     t = Template.parse("{% for item in collection %} {{ item }} {% endfor %}", profile: true)
-    t.render!("collection" => ["one", "two"])
+    t.render!({ "collection" => ["one", "two"] })
 
     assert_equal 1, t.profiler.length
     # Will profile each invocation of the for block

test/integration/standard_filter_test.rb

@@ -17,7 +17,7 @@ class TestThing
     "woot: #{@foo}"
   end
 
-  def [](_whatever)
+  def [](whatever)
     to_s
   end
 
@@ -37,7 +37,7 @@ class TestEnumerable < Liquid::Drop
   include Enumerable
 
   def each(&block)
-    [{ "foo" => 1, "bar" => 2 }, { "foo" => 2, "bar" => 1 }, { "foo" => 3, "bar" => 3 }].each(&block)
+    [ { "foo" => 1, "bar" => 2 }, { "foo" => 2, "bar" => 1 }, { "foo" => 3, "bar" => 3 } ].each(&block)
   end
 end
 
@@ -208,14 +208,14 @@ class StandardFiltersTest < Minitest::Test
       { "handle" => "beta" },
       { "price" => 1, "handle" => "gamma" },
       { "handle" => "delta" },
-      { "price" => 2, "handle" => "epsilon" },
+      { "price" => 2, "handle" => "epsilon" }
     ]
     expectation = [
       { "price" => 1, "handle" => "gamma" },
       { "price" => 2, "handle" => "epsilon" },
       { "price" => 4, "handle" => "alpha" },
       { "handle" => "delta" },
-      { "handle" => "beta" },
+      { "handle" => "beta" }
     ]
     assert_equal expectation, @filters.sort(input, "price")
   end
@@ -236,14 +236,14 @@ class StandardFiltersTest < Minitest::Test
       { "handle" => "beta" },
       { "price" => "1", "handle" => "gamma" },
       { "handle" => "delta" },
-      { "price" => 2, "handle" => "epsilon" },
+      { "price" => 2, "handle" => "epsilon" }
     ]
     expectation = [
       { "price" => "1", "handle" => "gamma" },
       { "price" => 2, "handle" => "epsilon" },
       { "price" => "4", "handle" => "alpha" },
       { "handle" => "delta" },
-      { "handle" => "beta" },
+      { "handle" => "beta" }
     ]
     assert_equal expectation, @filters.sort_natural(input, "price")
   end
@@ -256,7 +256,7 @@ class StandardFiltersTest < Minitest::Test
       { "fake" => "t" },
       { "key" => "a" },
       { "key" => "b" },
-      { "key" => "c" },
+      { "key" => "c" }
     ]
     expectation = [
       { "key" => "a" },
@@ -265,7 +265,7 @@ class StandardFiltersTest < Minitest::Test
       { "key" => "X" },
       { "key" => "Y" },
       { "key" => "Z" },
-      { "fake" => "t" },
+      { "fake" => "t" }
     ]
     assert_equal expectation, @filters.sort_natural(input, "key")
     assert_equal ["a", "b", "c", "X", "Y", "Z"], @filters.sort_natural(["X", "Y", "Z", "a", "b", "c"])
@@ -279,7 +279,7 @@ class StandardFiltersTest < Minitest::Test
     foo = [
       [1],
       [2],
-      [3],
+      [3]
     ]
 
     assert_raises Liquid::ArgumentError do
@@ -295,7 +295,7 @@ class StandardFiltersTest < Minitest::Test
     foo = [
       [1],
       [2],
-      [3],
+      [3]
     ]
 
     assert_raises Liquid::ArgumentError do
@@ -304,7 +304,7 @@ class StandardFiltersTest < Minitest::Test
   end
 
   def test_legacy_sort_hash
-    assert_equal [{ a: 1, b: 2 }], @filters.sort(a: 1, b: 2)
+    assert_equal [{ a: 1, b: 2 }], @filters.sort({ a: 1, b: 2 })
   end
 
   def test_numerical_vs_lexicographical_sort
@@ -330,7 +330,7 @@ class StandardFiltersTest < Minitest::Test
     foo = [
       [1],
       [2],
-      [3],
+      [3]
     ]
 
     assert_raises Liquid::ArgumentError do
@@ -346,7 +346,7 @@ class StandardFiltersTest < Minitest::Test
     foo = [
       [1],
       [2],
-      [3],
+      [3]
     ]
 
     assert_raises Liquid::ArgumentError do
@@ -380,7 +380,7 @@ class StandardFiltersTest < Minitest::Test
 
   def test_map_on_hashes
     assert_template_result "4217", '{{ thing | map: "foo" | map: "bar" }}',
-      "thing" => { "foo" => [{ "bar" => 42 }, { "bar" => 17 }] }
+      "thing" => { "foo" => [ { "bar" => 42 }, { "bar" => 17 } ] }
   end
 
   def test_legacy_map_on_hashes_with_dynamic_key
@@ -397,7 +397,7 @@ class StandardFiltersTest < Minitest::Test
 
   def test_map_over_proc
     drop = TestDrop.new
-    p = proc { drop }
+    p = proc{ drop }
     templ = '{{ procs | map: "test" }}'
     assert_template_result "testfoo", templ, "procs" => [p]
   end
@@ -405,10 +405,10 @@ class StandardFiltersTest < Minitest::Test
   def test_map_over_drops_returning_procs
     drops = [
       {
-        "proc" => -> { "foo" },
+        "proc" => ->{ "foo" },
       },
       {
-        "proc" => -> { "bar" },
+        "proc" => ->{ "bar" },
       },
     ]
     templ = '{{ drops | map: "proc" }}'
@@ -423,7 +423,7 @@ class StandardFiltersTest < Minitest::Test
     foo = [
       [1],
       [2],
-      [3],
+      [3]
     ]
 
     assert_raises Liquid::ArgumentError do
@@ -435,7 +435,7 @@ class StandardFiltersTest < Minitest::Test
     foo = [
       [1],
       [2],
-      [3],
+      [3]
     ]
     assert_raises Liquid::ArgumentError do
       @filters.map(foo, nil)
@@ -697,12 +697,12 @@ class StandardFiltersTest < Minitest::Test
       { "handle" => "alpha", "ok" => true },
       { "handle" => "beta", "ok" => false },
       { "handle" => "gamma", "ok" => false },
-      { "handle" => "delta", "ok" => true },
+      { "handle" => "delta", "ok" => true }
     ]
 
     expectation = [
       { "handle" => "alpha", "ok" => true },
-      { "handle" => "delta", "ok" => true },
+      { "handle" => "delta", "ok" => true }
     ]
 
     assert_equal expectation, @filters.where(input, "ok", true)
@@ -714,12 +714,12 @@ class StandardFiltersTest < Minitest::Test
       { "handle" => "alpha", "ok" => true },
       { "handle" => "beta" },
       { "handle" => "gamma" },
-      { "handle" => "delta", "ok" => true },
+      { "handle" => "delta", "ok" => true }
     ]
 
     expectation = [
       { "handle" => "alpha", "ok" => true },
-      { "handle" => "delta", "ok" => true },
+      { "handle" => "delta", "ok" => true }
     ]
 
     assert_equal expectation, @filters.where(input, "ok", true)
@@ -740,7 +740,7 @@ class StandardFiltersTest < Minitest::Test
     input = [
       { "message" => "Bonjour!", "language" => "French" },
       { "message" => "Hello!", "language" => "English" },
-      { "message" => "Hallo!", "language" => "German" },
+      { "message" => "Hallo!", "language" => "German" }
     ]
 
     assert_equal [{ "message" => "Bonjour!", "language" => "French" }], @filters.where(input, "language", "French")
@@ -758,7 +758,7 @@ class StandardFiltersTest < Minitest::Test
       { "foo" => false },
       { "foo" => true },
       { "foo" => "for sure" },
-      { "bar" => true },
+      { "bar" => true }
     ]
 
     assert_equal [{ "foo" => true }, { "foo" => "for sure" }], @filters.where(input, "foo")

test/integration/tags/echo_test.rb

@@ -1,11 +0,0 @@
-require 'test_helper'
-
-class EchoTest < Minitest::Test
-  include Liquid
-
-  def test_echo_outputs_its_input
-    assert_template_result('BAR', <<~LIQUID, 'variable-name' => 'bar')
-      {%- echo variable-name | upcase -%}
-    LIQUID
-  end
-end

test/integration/tags/for_tag_test.rb

@@ -23,19 +23,23 @@ class ForTagTest < Minitest::Test
   yo
 
 HERE
-    template = <<~HERE
+    template = <<HERE
-      {%for item in array%}
+{%for item in array%}
-        yo
+  yo
-      {%endfor%}
+{%endfor%}
-    HERE
+HERE
     assert_template_result(expected, template, 'array' => [1, 2, 3])
   end
 
   def test_for_reversed
-    assigns = { 'array' => [1, 2, 3] }
+    assigns = { 'array' => [ 1, 2, 3] }
     assert_template_result('321', '{%for item in array reversed %}{{item}}{%endfor%}', assigns)
   end
 
+  def test_for_range_reversed
+    assert_template_result('321', '{%for item in (1..3) reversed %}{{item}}{%endfor%}', {})
+  end
+
   def test_for_with_range
     assert_template_result(' 1  2  3 ', '{%for item in (1..3) %} {{item}} {%endfor%}')
 

test/integration/tags/if_else_tag_test.rb

@@ -132,7 +132,7 @@ class IfElseTagTest < Minitest::Test
   end
 
   def test_syntax_error_no_variable
-    assert_raises(SyntaxError) { assert_template_result('', '{% if jerry == 1 %}') }
+    assert_raises(SyntaxError){ assert_template_result('', '{% if jerry == 1 %}') }
   end
 
   def test_syntax_error_no_expression

test/integration/tags/include_tag_test.rb

@@ -40,14 +40,14 @@ class TestFileSystem
 end
 
 class OtherFileSystem
-  def read_template_file(_template_path)
+  def read_template_file(template_path)
     'from OtherFileSystem'
   end
 end
 
 class CountingFileSystem
   attr_reader :count
-  def read_template_file(_template_path)
+  def read_template_file(template_path)
     @count ||= 0
     @count += 1
     'from CountingFileSystem'
@@ -59,16 +59,15 @@ class CustomInclude < Liquid::Tag
 
   def initialize(tag_name, markup, tokens)
     markup =~ Syntax
-    @template_name = Regexp.last_match(1)
+    @template_name = $1
     super
   end
 
   def parse(tokens)
   end
 
-  def render_to_output_buffer(_context, output)
+  def render(context)
-    output << @template_name[1..-2]
+    @template_name[1..-2]
-    output
   end
 end
 
@@ -86,7 +85,7 @@ class IncludeTagTest < Minitest::Test
 
   def test_include_tag_with
     assert_template_result "Product: Draft 151cm ",
-      "{% include 'product' with products[0] %}", "products" => [{ 'title' => 'Draft 151cm' }, { 'title' => 'Element 155cm' }]
+      "{% include 'product' with products[0] %}", "products" => [ { 'title' => 'Draft 151cm' }, { 'title' => 'Element 155cm' } ]
   end
 
   def test_include_tag_with_default_name
@@ -96,7 +95,7 @@ class IncludeTagTest < Minitest::Test
 
   def test_include_tag_for
     assert_template_result "Product: Draft 151cm Product: Element 155cm ",
-      "{% include 'product' for products %}", "products" => [{ 'title' => 'Draft 151cm' }, { 'title' => 'Element 155cm' }]
+      "{% include 'product' for products %}", "products" => [ { 'title' => 'Draft 151cm' }, { 'title' => 'Element 155cm' } ]
   end
 
   def test_include_tag_with_local_variables
@@ -134,7 +133,7 @@ class IncludeTagTest < Minitest::Test
 
   def test_recursively_included_template_does_not_produce_endless_loop
     infinite_file_system = Class.new do
-      def read_template_file(_template_path)
+      def read_template_file(template_path)
         "-{% include 'loop' %}"
       end
     end

test/integration/tags/increment_tag_test.rb

@@ -13,11 +13,11 @@ class IncrementTagTest < Minitest::Test
   end
 
   def test_dec
-    assert_template_result('9', '{%decrement port %}', 'port' => 10)
+    assert_template_result('9', '{%decrement port %}', { 'port' => 10 })
     assert_template_result('-1 -2', '{%decrement port %} {%decrement port%}', {})
     assert_template_result('1 5 2 2 5',
       '{%increment port %} {%increment starboard%} ' \
       '{%increment port %} {%decrement port%} ' \
-      '{%decrement starboard %}', 'port' => 1, 'starboard' => 5)
+      '{%decrement starboard %}', { 'port' => 1, 'starboard' => 5 })
   end
 end

test/integration/tags/liquid_tag_test.rb

@@ -1,104 +0,0 @@
-require 'test_helper'
-
-class LiquidTagTest < Minitest::Test
-  include Liquid
-
-  def test_liquid_tag
-    assert_template_result('1 2 3', <<~LIQUID, 'array' => [1, 2, 3])
-      {%- liquid
-        echo array | join: " "
-      -%}
-    LIQUID
-
-    assert_template_result('1 2 3', <<~LIQUID, 'array' => [1, 2, 3])
-      {%- liquid
-        for value in array
-          echo value
-          unless forloop.last
-            echo " "
-          endunless
-        endfor
-      -%}
-    LIQUID
-
-    assert_template_result('4 8 12 6', <<~LIQUID, 'array' => [1, 2, 3])
-      {%- liquid
-        for value in array
-          assign double_value = value | times: 2
-          echo double_value | times: 2
-          unless forloop.last
-            echo " "
-          endunless
-        endfor
-
-        echo " "
-        echo double_value
-      -%}
-    LIQUID
-
-    assert_template_result('abc', <<~LIQUID)
-      {%- liquid echo "a" -%}
-      b
-      {%- liquid echo "c" -%}
-    LIQUID
-  end
-
-  def test_liquid_tag_errors
-    assert_match_syntax_error("syntax error (line 1): Unknown tag 'error'", <<~LIQUID)
-      {%- liquid error no such tag -%}
-    LIQUID
-
-    assert_match_syntax_error("syntax error (line 7): Unknown tag 'error'", <<~LIQUID)
-      {{ test }}
-
-      {%-
-      liquid
-        for value in array
-
-          error no such tag
-        endfor
-      -%}
-    LIQUID
-
-    assert_match_syntax_error("syntax error (line 2): Unknown tag '!!! the guards are vigilant'", <<~LIQUID)
-      {%- liquid
-        !!! the guards are vigilant
-      -%}
-    LIQUID
-
-    assert_match_syntax_error("syntax error (line 4): 'for' tag was never closed", <<~LIQUID)
-      {%- liquid
-        for value in array
-          echo 'forgot to close the for tag'
-      -%}
-    LIQUID
-  end
-
-  def test_line_number_is_correct_after_a_blank_token
-    assert_match_syntax_error("syntax error (line 3): Unknown tag 'error'", "{% liquid echo ''\n\n error %}")
-    assert_match_syntax_error("syntax error (line 3): Unknown tag 'error'", "{% liquid echo ''\n  \n error %}")
-  end
-
-  def test_cannot_open_blocks_living_past_a_liquid_tag
-    assert_match_syntax_error("syntax error (line 3): 'if' tag was never closed", <<~LIQUID)
-      {%- liquid
-        if true
-      -%}
-      {%- endif -%}
-    LIQUID
-  end
-
-  def test_quirk_can_close_blocks_created_before_a_liquid_tag
-    assert_template_result("42", <<~LIQUID)
-      {%- if true -%}
-      42
-      {%- liquid endif -%}
-    LIQUID
-  end
-
-  def test_liquid_tag_in_raw
-    assert_template_result("{% liquid echo 'test' %}\n", <<~LIQUID)
-      {% raw %}{% liquid echo 'test' %}{% endraw %}
-    LIQUID
-  end
-end

test/integration/tags/render_tag_test.rb

@@ -1,149 +0,0 @@
-require 'test_helper'
-
-class RenderTagTest < Minitest::Test
-  include Liquid
-
-  def test_render_with_no_arguments
-    Liquid::Template.file_system = StubFileSystem.new('source' => 'rendered content')
-    assert_template_result 'rendered content', '{% render "source" %}'
-  end
-
-  def test_render_tag_looks_for_file_system_in_registers_first
-    file_system = StubFileSystem.new('pick_a_source' => 'from register file system')
-    assert_equal 'from register file system',
-      Template.parse('{% render "pick_a_source" %}').render!({}, registers: { file_system: file_system })
-  end
-
-  def test_render_passes_named_arguments_into_inner_scope
-    Liquid::Template.file_system = StubFileSystem.new('product' => '{{ inner_product.title }}')
-    assert_template_result 'My Product', '{% render "product", inner_product: outer_product %}',
-      'outer_product' => { 'title' => 'My Product' }
-  end
-
-  def test_render_accepts_literals_as_arguments
-    Liquid::Template.file_system = StubFileSystem.new('snippet' => '{{ price }}')
-    assert_template_result '123', '{% render "snippet", price: 123 %}'
-  end
-
-  def test_render_accepts_multiple_named_arguments
-    Liquid::Template.file_system = StubFileSystem.new('snippet' => '{{ one }} {{ two }}')
-    assert_template_result '1 2', '{% render "snippet", one: 1, two: 2 %}'
-  end
-
-  def test_render_does_not_inherit_parent_scope_variables
-    Liquid::Template.file_system = StubFileSystem.new('snippet' => '{{ outer_variable }}')
-    assert_template_result '', '{% assign outer_variable = "should not be visible" %}{% render "snippet" %}'
-  end
-
-  def test_render_does_not_inherit_variable_with_same_name_as_snippet
-    Liquid::Template.file_system = StubFileSystem.new('snippet' => '{{ snippet }}')
-    assert_template_result '', "{% assign snippet = 'should not be visible' %}{% render 'snippet' %}"
-  end
-
-  def test_render_sets_the_correct_template_name_for_errors
-    Liquid::Template.file_system = StubFileSystem.new('snippet' => '{{ unsafe }}')
-
-    with_taint_mode :error do
-      template = Liquid::Template.parse('{% render "snippet", unsafe: unsafe %}')
-      context = Context.new('unsafe' => (+'unsafe').tap(&:taint))
-      template.render(context)
-
-      assert_equal [Liquid::TaintedError], template.errors.map(&:class)
-      assert_equal 'snippet', template.errors.first.template_name
-    end
-  end
-
-  def test_render_sets_the_correct_template_name_for_warnings
-    Liquid::Template.file_system = StubFileSystem.new('snippet' => '{{ unsafe }}')
-
-    with_taint_mode :warn do
-      template = Liquid::Template.parse('{% render "snippet", unsafe: unsafe %}')
-      context = Context.new('unsafe' => (+'unsafe').tap(&:taint))
-      template.render(context)
-
-      assert_equal [Liquid::TaintedError], context.warnings.map(&:class)
-      assert_equal 'snippet', context.warnings.first.template_name
-    end
-  end
-
-  def test_render_does_not_mutate_parent_scope
-    Liquid::Template.file_system = StubFileSystem.new('snippet' => '{% assign inner = 1 %}')
-    assert_template_result '', "{% render 'snippet' %}{{ inner }}"
-  end
-
-  def test_nested_render_tag
-    Liquid::Template.file_system = StubFileSystem.new(
-      'one' => "one {% render 'two' %}",
-      'two' => 'two'
-    )
-    assert_template_result 'one two', "{% render 'one' %}"
-  end
-
-  def test_recursively_rendered_template_does_not_produce_endless_loop
-    Liquid::Template.file_system = StubFileSystem.new('loop' => '{% render "loop" %}')
-
-    assert_raises Liquid::StackLevelError do
-      Template.parse('{% render "loop" %}').render!
-    end
-  end
-
-  def test_includes_and_renders_count_towards_the_same_recursion_limit
-    Liquid::Template.file_system = StubFileSystem.new(
-      'loop_render' => '{% render "loop_include" %}',
-      'loop_include' => '{% include "loop_render" %}'
-    )
-
-    assert_raises Liquid::StackLevelError  do
-      Template.parse('{% render "loop_include" %}').render!
-    end
-  end
-
-  def test_dynamically_choosen_templates_are_not_allowed
-    Liquid::Template.file_system = StubFileSystem.new('snippet' => 'should not be rendered')
-
-    assert_raises Liquid::SyntaxError do
-      Liquid::Template.parse("{% assign name = 'snippet' %}{% render name %}")
-    end
-  end
-
-  def test_include_tag_caches_second_read_of_same_partial
-    file_system = StubFileSystem.new('snippet' => 'echo')
-    assert_equal 'echoecho',
-      Template.parse('{% render "snippet" %}{% render "snippet" %}')
-      .render!({}, registers: { file_system: file_system })
-    assert_equal 1, file_system.file_read_count
-  end
-
-  def test_render_tag_doesnt_cache_partials_across_renders
-    file_system = StubFileSystem.new('snippet' => 'my message')
-
-    assert_equal 'my message',
-      Template.parse('{% include "snippet" %}').render!({}, registers: { file_system: file_system })
-    assert_equal 1, file_system.file_read_count
-
-    assert_equal 'my message',
-      Template.parse('{% include "snippet" %}').render!({}, registers: { file_system: file_system })
-    assert_equal 2, file_system.file_read_count
-  end
-
-  def test_render_tag_within_if_statement
-    Liquid::Template.file_system = StubFileSystem.new('snippet' => 'my message')
-    assert_template_result 'my message', '{% if true %}{% render "snippet" %}{% endif %}'
-  end
-
-  def test_break_through_render
-    Liquid::Template.file_system = StubFileSystem.new('break' => '{% break %}')
-    assert_template_result '1', '{% for i in (1..3) %}{{ i }}{% break %}{{ i }}{% endfor %}'
-    assert_template_result '112233', '{% for i in (1..3) %}{{ i }}{% render "break" %}{{ i }}{% endfor %}'
-  end
-
-  def test_increment_is_isolated_between_renders
-    Liquid::Template.file_system = StubFileSystem.new('incr' => '{% increment %}')
-    assert_template_result '010', '{% increment %}{% increment %}{% render "incr" %}'
-  end
-
-  def test_decrement_is_isolated_between_renders
-    Liquid::Template.file_system = StubFileSystem.new('decr' => '{% decrement %}')
-    assert_template_result '-1-2-1', '{% decrement %}{% decrement %}{% render "decr" %}'
-  end
-end

test/integration/tags/standard_tag_test.rb

@@ -69,7 +69,7 @@ class StandardTagTest < Minitest::Test
     assert_raises(SyntaxError) do
       assert_template_result('content foo content foo ',
         '{{ var2 }}{% capture %}{{ var }} foo {% endcapture %}{{ var2 }}{{ var2 }}',
-        'var' => 'content')
+        { 'var' => 'content' })
     end
   end
 
@@ -183,32 +183,32 @@ class StandardTagTest < Minitest::Test
 
   def test_case_when_or
     code = '{% case condition %}{% when 1 or 2 or 3 %} its 1 or 2 or 3 {% when 4 %} its 4 {% endcase %}'
-    assert_template_result(' its 1 or 2 or 3 ', code, 'condition' => 1)
+    assert_template_result(' its 1 or 2 or 3 ', code, { 'condition' => 1 })
-    assert_template_result(' its 1 or 2 or 3 ', code, 'condition' => 2)
+    assert_template_result(' its 1 or 2 or 3 ', code, { 'condition' => 2 })
-    assert_template_result(' its 1 or 2 or 3 ', code, 'condition' => 3)
+    assert_template_result(' its 1 or 2 or 3 ', code, { 'condition' => 3 })
-    assert_template_result(' its 4 ', code, 'condition' => 4)
+    assert_template_result(' its 4 ', code, { 'condition' => 4 })
-    assert_template_result('', code, 'condition' => 5)
+    assert_template_result('', code, { 'condition' => 5 })
 
     code = '{% case condition %}{% when 1 or "string" or null %} its 1 or 2 or 3 {% when 4 %} its 4 {% endcase %}'
-    assert_template_result(' its 1 or 2 or 3 ', code, 'condition' => 1)
+    assert_template_result(' its 1 or 2 or 3 ', code, { 'condition' => 1 })
-    assert_template_result(' its 1 or 2 or 3 ', code, 'condition' => 'string')
+    assert_template_result(' its 1 or 2 or 3 ', code, { 'condition' => 'string' })
-    assert_template_result(' its 1 or 2 or 3 ', code, 'condition' => nil)
+    assert_template_result(' its 1 or 2 or 3 ', code, { 'condition' => nil })
-    assert_template_result('', code, 'condition' => 'something else')
+    assert_template_result('', code, { 'condition' => 'something else' })
   end
 
   def test_case_when_comma
     code = '{% case condition %}{% when 1, 2, 3 %} its 1 or 2 or 3 {% when 4 %} its 4 {% endcase %}'
-    assert_template_result(' its 1 or 2 or 3 ', code, 'condition' => 1)
+    assert_template_result(' its 1 or 2 or 3 ', code, { 'condition' => 1 })
-    assert_template_result(' its 1 or 2 or 3 ', code, 'condition' => 2)
+    assert_template_result(' its 1 or 2 or 3 ', code, { 'condition' => 2 })
-    assert_template_result(' its 1 or 2 or 3 ', code, 'condition' => 3)
+    assert_template_result(' its 1 or 2 or 3 ', code, { 'condition' => 3 })
-    assert_template_result(' its 4 ', code, 'condition' => 4)
+    assert_template_result(' its 4 ', code, { 'condition' => 4 })
-    assert_template_result('', code, 'condition' => 5)
+    assert_template_result('', code, { 'condition' => 5 })
 
     code = '{% case condition %}{% when 1, "string", null %} its 1 or 2 or 3 {% when 4 %} its 4 {% endcase %}'
-    assert_template_result(' its 1 or 2 or 3 ', code, 'condition' => 1)
+    assert_template_result(' its 1 or 2 or 3 ', code, { 'condition' => 1 })
-    assert_template_result(' its 1 or 2 or 3 ', code, 'condition' => 'string')
+    assert_template_result(' its 1 or 2 or 3 ', code, { 'condition' => 'string' })
-    assert_template_result(' its 1 or 2 or 3 ', code, 'condition' => nil)
+    assert_template_result(' its 1 or 2 or 3 ', code, { 'condition' => nil })
-    assert_template_result('', code, 'condition' => 'something else')
+    assert_template_result('', code, { 'condition' => 'something else' })
   end
 
   def test_assign
@@ -283,10 +283,10 @@ class StandardTagTest < Minitest::Test
   end
 
   def test_ifchanged
-    assigns = { 'array' => [1, 1, 2, 2, 3, 3] }
+    assigns = { 'array' => [ 1, 1, 2, 2, 3, 3] }
     assert_template_result('123', '{%for item in array%}{%ifchanged%}{{item}}{% endifchanged %}{%endfor%}', assigns)
 
-    assigns = { 'array' => [1, 1, 1, 1] }
+    assigns = { 'array' => [ 1, 1, 1, 1] }
     assert_template_result('1', '{%for item in array%}{%ifchanged%}{{item}}{% endifchanged %}{%endfor%}', assigns)
   end
 

test/integration/template_test.rb

@@ -224,7 +224,7 @@ class TemplateTest < Minitest::Test
   end
 
   def test_render_bang_force_rethrow_errors_on_passed_context
-    context = Context.new('drop' => ErroneousDrop.new)
+    context = Context.new({ 'drop' => ErroneousDrop.new })
     t = Template.new.parse('{{ drop.bad_method }}')
 
     e = assert_raises RuntimeError do
@@ -267,7 +267,7 @@ class TemplateTest < Minitest::Test
 
   def test_undefined_variables
     t = Template.parse("{{x}} {{y}} {{z.a}} {{z.b}} {{z.c.d}}")
-    result = t.render({ 'x' => 33, 'z' => { 'a' => 32, 'c' => { 'e' => 31 } } }, strict_variables: true)
+    result = t.render({ 'x' => 33, 'z' => { 'a' => 32, 'c' => { 'e' => 31 } } }, { strict_variables: true })
 
     assert_equal '33  32  ', result
     assert_equal 3, t.errors.count
@@ -292,14 +292,14 @@ class TemplateTest < Minitest::Test
     t = Template.parse("{{x}} {{y}} {{z.a}} {{z.b}} {{z.c.d}}")
 
     assert_raises UndefinedVariable do
-      t.render!({ 'x' => 33, 'z' => { 'a' => 32, 'c' => { 'e' => 31 } } }, strict_variables: true)
+      t.render!({ 'x' => 33, 'z' => { 'a' => 32, 'c' => { 'e' => 31 } } }, { strict_variables: true })
     end
   end
 
   def test_undefined_drop_methods
     d = DropWithUndefinedMethod.new
     t = Template.new.parse('{{ foo }} {{ woot }}')
-    result = t.render(d, strict_variables: true)
+    result = t.render(d, { strict_variables: true })
 
     assert_equal 'foo ', result
     assert_equal 1, t.errors.count
@@ -311,7 +311,7 @@ class TemplateTest < Minitest::Test
     t = Template.new.parse('{{ foo }} {{ woot }}')
 
     assert_raises UndefinedDropMethod do
-      t.render!(d, strict_variables: true)
+      t.render!(d, { strict_variables: true })
     end
   end
 
@@ -322,7 +322,7 @@ class TemplateTest < Minitest::Test
         "-#{v}-"
       end
     end
-    result = t.render({ 'a' => 123, 'x' => 'foo' }, filters: [filters], strict_filters: true)
+    result = t.render({ 'a' => 123, 'x' => 'foo' }, { filters: [filters], strict_filters: true })
 
     assert_equal '123 ', result
     assert_equal 1, t.errors.count
@@ -334,17 +334,17 @@ class TemplateTest < Minitest::Test
     t = Template.parse("{{x | somefilter1 | upcase | somefilter2}}")
 
     assert_raises UndefinedFilter do
-      t.render!({ 'x' => 'foo' }, strict_filters: true)
+      t.render!({ 'x' => 'foo' }, { strict_filters: true })
     end
   end
 
   def test_using_range_literal_works_as_expected
     t = Template.parse("{% assign foo = (x..y) %}{{ foo }}")
-    result = t.render('x' => 1, 'y' => 5)
+    result = t.render({ 'x' => 1, 'y' => 5 })
     assert_equal '1..5', result
 
     t = Template.parse("{% assign nums = (x..y) %}{% for num in nums %}{{ num }}{% endfor %}")
-    result = t.render('x' => 1, 'y' => 5)
+    result = t.render({ 'x' => 1, 'y' => 5 })
     assert_equal '12345', result
   end
 end

test/integration/trim_mode_test.rb

@@ -76,14 +76,14 @@ class TrimModeTest < Minitest::Test
         </p>
       </div>
     END_TEMPLATE
-    expected = <<~END_EXPECTED
+    expected = <<-END_EXPECTED
-            <div>
+      <div>
-              <p>
+        <p>
-      #{whitespace}
+#{whitespace}
-                yes
+          yes
-      #{whitespace}
+#{whitespace}
-              </p>
+        </p>
-            </div>
+      </div>
     END_EXPECTED
     assert_template_result(expected, text)
 
@@ -96,12 +96,12 @@ class TrimModeTest < Minitest::Test
         </p>
       </div>
     END_TEMPLATE
-    expected = <<~END_EXPECTED
+    expected = <<-END_EXPECTED
-            <div>
+      <div>
-              <p>
+        <p>
-      #{whitespace}
+#{whitespace}
-              </p>
+        </p>
-            </div>
+      </div>
     END_EXPECTED
     assert_template_result(expected, text)
   end
@@ -337,12 +337,12 @@ class TrimModeTest < Minitest::Test
         </p>
       </div>
     END_TEMPLATE
-    expected = <<~END_EXPECTED
+    expected = <<-END_EXPECTED
-            <div>
+      <div>
-              <p>
+        <p>
-      #{whitespace}
+#{whitespace}
-              </p>
+        </p>
-            </div>
+      </div>
     END_EXPECTED
     assert_template_result(expected, text)
   end
@@ -513,16 +513,16 @@ class TrimModeTest < Minitest::Test
         {% endraw %}
       </div>
     END_TEMPLATE
-    expected = <<~END_EXPECTED
+    expected = <<-END_EXPECTED
-            <div>
+      <div>
-      #{whitespace}
+#{whitespace}
-                {%- if true -%}
+          {%- if true -%}
-                  <p>
+            <p>
-                    {{- 'John' -}}
+              {{- 'John' -}}
-                  </p>
+            </p>
-                {%- endif -%}
+          {%- endif -%}
-      #{whitespace}
+#{whitespace}
-            </div>
+      </div>
     END_EXPECTED
     assert_template_result(expected, text)
   end

test/integration/variable_test.rb

@@ -76,7 +76,7 @@ class VariableTest < Minitest::Test
 
   def test_hash_with_default_proc
     template = Template.parse(%(Hello {{ test }}))
-    assigns = Hash.new { |_h, k| raise "Unknown variable '#{k}'" }
+    assigns = Hash.new { |h, k| raise "Unknown variable '#{k}'" }
     assigns['test'] = 'Tobi'
     assert_equal 'Hello Tobi', template.render!(assigns)
     assigns.delete('test')

test/test_helper.rb

@@ -14,7 +14,7 @@ if env_mode = ENV['LIQUID_PARSER_MODE']
 end
 Liquid::Template.error_mode = mode
 
-if ENV['LIQUID_C'] == '1'
+if ENV['LIQUID-C'] == '1'
   puts "-- LIQUID C"
   require 'liquid/c'
 end
@@ -37,18 +37,18 @@ module Minitest
     include Liquid
 
     def assert_template_result(expected, template, assigns = {}, message = nil)
-      assert_equal expected, Template.parse(template, line_numbers: true).render!(assigns), message
+      assert_equal expected, Template.parse(template).render!(assigns), message
     end
 
     def assert_template_result_matches(expected, template, assigns = {}, message = nil)
-      return assert_template_result(expected, template, assigns, message) unless expected.is_a?(Regexp)
+      return assert_template_result(expected, template, assigns, message) unless expected.is_a? Regexp
 
-      assert_match expected, Template.parse(template, line_numbers: true).render!(assigns), message
+      assert_match expected, Template.parse(template).render!(assigns), message
     end
 
     def assert_match_syntax_error(match, template, assigns = {})
       exception = assert_raises(Liquid::SyntaxError) do
-        Template.parse(template, line_numbers: true).render(assigns)
+        Template.parse(template).render(assigns)
       end
       assert_match match, exception.message
     end
@@ -84,13 +84,6 @@ module Minitest
     ensure
       Liquid::Template.error_mode = old_mode
     end
-
-    def with_custom_tag(tag_name, tag_class)
-      Liquid::Template.register_tag(tag_name, tag_class)
-      yield
-    ensure
-      Liquid::Template.tags.delete(tag_name)
-    end
   end
 end
 
@@ -121,17 +114,3 @@ class ErrorDrop < Liquid::Drop
     raise Exception, 'exception'
   end
 end
-
-class StubFileSystem
-  attr_reader :file_read_count
-
-  def initialize(values)
-    @file_read_count = 0
-    @values = values
-  end
-
-  def read_template_file(template_path)
-    @file_read_count += 1
-    @values.fetch(template_path)
-  end
-end

test/unit/block_unit_test.rb

@@ -44,47 +44,10 @@ class BlockUnitTest < Minitest::Test
   end
 
   def test_with_custom_tag
-    with_custom_tag('testtag', Block) do
+    Liquid::Template.register_tag("testtag", Block)
-      assert Liquid::Template.parse("{% testtag %} {% endtesttag %}")
+    assert Liquid::Template.parse("{% testtag %} {% endtesttag %}")
-    end
+  ensure
-  end
+    Liquid::Template.tags.delete('testtag')
-
-  def test_custom_block_tags_have_a_default_render_to_output_buffer_method_for_backwards_compatibility
-    klass1 = Class.new(Block) do
-      def render(*)
-        'hello'
-      end
-    end
-
-    with_custom_tag('blabla', klass1) do
-      template = Liquid::Template.parse("{% blabla %} bla {% endblabla %}")
-
-      assert_equal 'hello', template.render
-
-      buf = ''
-      output = template.render({}, output: buf)
-      assert_equal 'hello', output
-      assert_equal 'hello', buf
-      assert_equal buf.object_id, output.object_id
-    end
-
-    klass2 = Class.new(klass1) do
-      def render(*)
-        'foo' + super + 'bar'
-      end
-    end
-
-    with_custom_tag('blabla', klass2) do
-      template = Liquid::Template.parse("{% blabla %} foo {% endblabla %}")
-
-      assert_equal 'foohellobar', template.render
-
-      buf = ''
-      output = template.render({}, output: buf)
-      assert_equal 'foohellobar', output
-      assert_equal 'foohellobar', buf
-      assert_equal buf.object_id, output.object_id
-    end
   end
 
   private

test/unit/condition_unit_test.rb

@@ -68,7 +68,7 @@ class ConditionUnitTest < Minitest::Test
     assert_nil Condition.new({}, '>', 2).evaluate
     assert_nil Condition.new(2, '>', {}).evaluate
     assert_equal false, Condition.new({}, '==', 2).evaluate
-    assert_equal true, Condition.new({ 'a' => 1 }, '==', 'a' => 1).evaluate
+    assert_equal true, Condition.new({ 'a' => 1 }, '==', { 'a' => 1 }).evaluate
     assert_equal true, Condition.new({ 'a' => 2 }, 'contains', 'a').evaluate
   end
 
@@ -107,11 +107,11 @@ class ConditionUnitTest < Minitest::Test
 
     assert_equal false, condition.evaluate
 
-    condition.or(Condition.new(2, '==', 1))
+    condition.or Condition.new(2, '==', 1)
 
     assert_equal false, condition.evaluate
 
-    condition.or(Condition.new(1, '==', 1))
+    condition.or Condition.new(1, '==', 1)
 
     assert_equal true, condition.evaluate
   end
@@ -121,22 +121,22 @@ class ConditionUnitTest < Minitest::Test
 
     assert_equal true, condition.evaluate
 
-    condition.and(Condition.new(2, '==', 2))
+    condition.and Condition.new(2, '==', 2)
 
     assert_equal true, condition.evaluate
 
-    condition.and(Condition.new(2, '==', 1))
+    condition.and Condition.new(2, '==', 1)
 
     assert_equal false, condition.evaluate
   end
 
   def test_should_allow_custom_proc_operator
-    Condition.operators['starts_with'] = proc { |_cond, left, right| left =~ /^#{right}/ }
+    Condition.operators['starts_with'] = proc { |cond, left, right| left =~ %r{^#{right}} }
 
     assert_evaluates_true 'bob', 'starts_with', 'b'
     assert_evaluates_false 'bob', 'starts_with', 'o'
   ensure
-    Condition.operators.delete('starts_with')
+    Condition.operators.delete 'starts_with'
   end
 
   def test_left_or_right_may_contain_operators

test/unit/context_unit_test.rb

@@ -206,9 +206,9 @@ class ContextUnitTest < Minitest::Test
   end
 
   def test_merge
-    @context.merge("test" => "test")
+    @context.merge({ "test" => "test" })
     assert_equal 'test', @context['test']
-    @context.merge("test" => "newvalue", "foo" => "bar")
+    @context.merge({ "test" => "newvalue", "foo" => "bar" })
     assert_equal 'newvalue', @context['test']
     assert_equal 'bar', @context['foo']
   end
@@ -235,10 +235,10 @@ class ContextUnitTest < Minitest::Test
 
   def test_hash_to_array_transition
     @context['colors'] = {
-      'Blue' => ['003366', '336699', '6699CC', '99CCFF'],
+      'Blue'    => ['003366', '336699', '6699CC', '99CCFF'],
-      'Green' => ['003300', '336633', '669966', '99CC99'],
+      'Green'   => ['003300', '336633', '669966', '99CC99'],
-      'Yellow' => ['CC9900', 'FFCC00', 'FFFF99', 'FFFFCC'],
+      'Yellow'  => ['CC9900', 'FFCC00', 'FFFF99', 'FFFFCC'],
-      'Red' => ['660000', '993333', 'CC6666', 'FF9999'],
+      'Red'     => ['660000', '993333', 'CC6666', 'FF9999']
     }
 
     assert_equal '003366', @context['colors.Blue[0]']
@@ -263,7 +263,7 @@ class ContextUnitTest < Minitest::Test
 
   def test_access_hashes_with_hash_notation
     @context['products'] = { 'count' => 5, 'tags' => ['deepsnow', 'freestyle'] }
-    @context['product'] = { 'variants' => [{ 'title' => 'draft151cm' }, { 'title' => 'element151cm' }] }
+    @context['product'] = { 'variants' => [ { 'title' => 'draft151cm' }, { 'title' => 'element151cm' } ] }
 
     assert_equal 5, @context['products["count"]']
     assert_equal 'deepsnow', @context['products["tags"][0]']
@@ -301,7 +301,7 @@ class ContextUnitTest < Minitest::Test
   end
 
   def test_first_can_appear_in_middle_of_callchain
-    @context['product'] = { 'variants' => [{ 'title' => 'draft151cm' }, { 'title' => 'element151cm' }] }
+    @context['product'] = { 'variants' => [ { 'title' => 'draft151cm' }, { 'title' => 'element151cm' } ] }
 
     assert_equal 'draft151cm', @context['product.variants[0].title']
     assert_equal 'element151cm', @context['product.variants[1].title']
@@ -349,9 +349,9 @@ class ContextUnitTest < Minitest::Test
 
   def test_ranges
     @context.merge("test" => '5')
-    assert_equal (1..5), @context['(1..5)']
+    assert_equal ReversableRange.new(1, 5), @context['(1..5)']
-    assert_equal (1..5), @context['(1..test)']
+    assert_equal ReversableRange.new(1, 5), @context['(1..test)']
-    assert_equal (5..5), @context['(test..test)']
+    assert_equal ReversableRange.new(5, 5), @context['(test..test)']
   end
 
   def test_cents_through_drop_nestedly
@@ -453,7 +453,7 @@ class ContextUnitTest < Minitest::Test
   end
 
   def test_context_initialization_with_a_proc_in_environment
-    contx = Context.new([test: ->(c) { c['poutine'] }], test: :foo)
+    contx = Context.new([test: ->(c) { c['poutine'] }], { test: :foo })
 
     assert contx
     assert_nil contx['poutine']
@@ -468,79 +468,11 @@ class ContextUnitTest < Minitest::Test
     assert_equal 'hi filtered', context.apply_global_filter('hi')
   end
 
-  def test_static_environments_are_read_with_lower_priority_than_environments
-    context = Context.build(
-      static_environments: { 'shadowed' => 'static', 'unshadowed' => 'static' },
-      environments: { 'shadowed' => 'dynamic' }
-    )
-
-    assert_equal 'dynamic', context['shadowed']
-    assert_equal 'static', context['unshadowed']
-  end
-
   def test_apply_global_filter_when_no_global_filter_exist
     context = Context.new
     assert_equal 'hi', context.apply_global_filter('hi')
   end
 
-  def test_new_isolated_subcontext_does_not_inherit_variables
-    super_context = Context.new
-    super_context['my_variable'] = 'some value'
-    subcontext = super_context.new_isolated_subcontext
-
-    assert_nil subcontext['my_variable']
-  end
-
-  def test_new_isolated_subcontext_inherits_static_environment
-    super_context = Context.build(static_environments: { 'my_environment_value' => 'my value' })
-    subcontext = super_context.new_isolated_subcontext
-
-    assert_equal 'my value', subcontext['my_environment_value']
-  end
-
-  def test_new_isolated_subcontext_inherits_resource_limits
-    resource_limits = ResourceLimits.new({})
-    super_context = Context.new({}, {}, {}, false, resource_limits)
-    subcontext = super_context.new_isolated_subcontext
-    assert_equal resource_limits, subcontext.resource_limits
-  end
-
-  def test_new_isolated_subcontext_inherits_exception_renderer
-    super_context = Context.new
-    super_context.exception_renderer = ->(_e) { 'my exception message' }
-    subcontext = super_context.new_isolated_subcontext
-    assert_equal 'my exception message', subcontext.handle_error(Liquid::Error.new)
-  end
-
-  def test_new_isolated_subcontext_does_not_inherit_non_static_registers
-    registers = {
-      my_register: :my_value,
-    }
-    super_context = Context.new({}, {}, registers)
-    subcontext = super_context.new_isolated_subcontext
-    assert_nil subcontext.registers[:my_register]
-  end
-
-  def test_new_isolated_subcontext_inherits_static_registers
-    super_context = Context.build(static_registers: { my_register: :my_value })
-    subcontext = super_context.new_isolated_subcontext
-    assert_equal :my_value, subcontext.static_registers[:my_register]
-  end
-
-  def test_new_isolated_subcontext_inherits_filters
-    my_filter = Module.new do
-      def my_filter(*)
-        'my filter result'
-      end
-    end
-
-    super_context = Context.new
-    super_context.add_filters([my_filter])
-    subcontext = super_context.new_isolated_subcontext
-    template = Template.parse('{{ 123 | my_filter }}')
-    assert_equal 'my filter result', template.render(subcontext)
-  end
-
   private
 
   def assert_no_object_allocations

test/unit/partial_cache_unit_test.rb

@@ -1,91 +0,0 @@
-require 'test_helper'
-
-class PartialCacheUnitTest < Minitest::Test
-  def test_uses_the_file_system_register_if_present
-    context = Liquid::Context.build(
-      registers: {
-        file_system: StubFileSystem.new('my_partial' => 'my partial body'),
-      }
-    )
-
-    partial = Liquid::PartialCache.load(
-      'my_partial',
-      context: context,
-      parse_context: Liquid::ParseContext.new
-    )
-
-    assert_equal 'my partial body', partial.render
-  end
-
-  def test_reads_from_the_file_system_only_once_per_file
-    file_system = StubFileSystem.new('my_partial' => 'some partial body')
-    context = Liquid::Context.build(
-      registers: { file_system: file_system }
-    )
-
-    2.times do
-      Liquid::PartialCache.load(
-        'my_partial',
-        context: context,
-        parse_context: Liquid::ParseContext.new
-      )
-    end
-
-    assert_equal 1, file_system.file_read_count
-  end
-
-  def test_cache_state_is_stored_per_context
-    parse_context = Liquid::ParseContext.new
-    shared_file_system = StubFileSystem.new(
-      'my_partial' => 'my shared value'
-    )
-    context_one = Liquid::Context.build(
-      registers: {
-        file_system: shared_file_system,
-      }
-    )
-    context_two = Liquid::Context.build(
-      registers: {
-        file_system: shared_file_system,
-      }
-    )
-
-    2.times do
-      Liquid::PartialCache.load(
-        'my_partial',
-        context: context_one,
-        parse_context: parse_context
-      )
-    end
-
-    Liquid::PartialCache.load(
-      'my_partial',
-      context: context_two,
-      parse_context: parse_context
-    )
-
-    assert_equal 2, shared_file_system.file_read_count
-  end
-
-  def test_cache_is_not_broken_when_a_different_parse_context_is_used
-    file_system = StubFileSystem.new('my_partial' => 'some partial body')
-    context = Liquid::Context.build(
-      registers: { file_system: file_system }
-    )
-
-    Liquid::PartialCache.load(
-      'my_partial',
-      context: context,
-      parse_context: Liquid::ParseContext.new(my_key: 'value one')
-    )
-    Liquid::PartialCache.load(
-      'my_partial',
-      context: context,
-      parse_context: Liquid::ParseContext.new(my_key: 'value two')
-    )
-
-    # Technically what we care about is that the file was parsed twice,
-    # but measuring file reads is an OK proxy for this.
-    assert_equal 1, file_system.file_read_count
-  end
-end

test/unit/reversable_range_unit_test.rb

@@ -0,0 +1,116 @@
+require 'test_helper'
+
+class ReversableRangeTest < Minitest::Test
+  include Liquid
+
+  def test_each_iterates_through_items_in_the_range
+    actual_items = []
+    ReversableRange.new(1, 10).each { |item| actual_items << item }
+
+    expected_items = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
+    assert_equal expected_items, actual_items
+  end
+
+  def test_implements_enumerable
+    actual_items = ReversableRange.new(1, 10).select(&:even?)
+
+    expected_items = [2, 4, 6, 8, 10]
+    assert_equal expected_items, actual_items
+  end
+
+  def test_is_not_empty_max_greater_than_min
+    range = ReversableRange.new(9, 10)
+
+    refute_predicate range, :empty?
+  end
+
+  def test_is_not_empty_max_equal_to_min
+    range = ReversableRange.new(10, 10)
+
+    refute_predicate range, :empty?
+  end
+
+  def test_is_empty_if_not_reversed_and_max_less_than_min
+    range = ReversableRange.new(10, 9)
+
+    assert_predicate range, :empty?
+  end
+
+  def test_ranges_with_the_same_max_and_min_have_one_element
+    actual_items = ReversableRange.new(1337, 1337).to_a
+    expected_items = [1337]
+    assert_equal expected_items, actual_items
+  end
+
+  def test_load_slice_returns_a_sub_range
+    actual_items = ReversableRange.new(1, 10).load_slice(5, 8).to_a
+
+    expected_items = [5, 6, 7, 8]
+    assert_equal expected_items, actual_items
+  end
+
+  def test_load_slice_returns_a_reversed_sub_range_if_reversed
+    range = ReversableRange.new(1, 10)
+    range.reverse!
+    actual_items = range.load_slice(5, 8).to_a
+
+    expected_items = [8, 7, 6, 5]
+    assert_equal expected_items, actual_items
+  end
+
+  def test_is_equal_to_other_if_also_a_reversable_range_and_has_same_properties
+    one = ReversableRange.new(1, 10)
+    one.reverse!
+
+    two = ReversableRange.new(1, 10)
+    two.reverse!
+
+    assert_equal one, two
+  end
+
+  def test_is_not_equal_to_a_non_reversable_range
+    range = ReversableRange.new(1, 10)
+    range.reverse!
+
+    refute_equal range, :something_else
+  end
+
+  def test_is_not_equal_if_ranges_have_different_mins
+    one = ReversableRange.new(1, 10)
+    two = ReversableRange.new(2, 10)
+
+    refute_equal one, two
+  end
+
+  def test_is_not_equal_if_ranges_have_different_maxes
+    one = ReversableRange.new(1, 10)
+    two = ReversableRange.new(1, 11)
+
+    refute_equal one, two
+  end
+
+  def test_is_not_equal_if_only_one_is_reversed
+    one = ReversableRange.new(1, 10)
+
+    two = ReversableRange.new(1, 10)
+    two.reverse!
+
+    refute_equal one, two
+  end
+
+  def test_to_s_mirrors_rubys_range_syntax
+    range = ReversableRange.new(1, 10)
+    assert_equal '1..10', range.to_s
+  end
+
+  def test_to_s_reverses_when_reversed
+    range = ReversableRange.new(1, 10)
+    range.reverse!
+    assert_equal '10..1', range.to_s
+  end
+
+  def test_size
+    range = ReversableRange.new(1, 10)
+    assert_equal 10, range.size
+  end
+end

test/unit/strainer_unit_test.rb

@@ -36,8 +36,7 @@ class StrainerUnitTest < Minitest::Test
     rescue Liquid::ArgumentError => e
       assert_match(
         /\ALiquid error: wrong number of arguments \((1 for 0|given 1, expected 0)\)\z/,
-        e.message
+        e.message)
-      )
       assert_equal e.backtrace[0].split(':')[0], __FILE__
     end
   end
@@ -136,7 +135,7 @@ class StrainerUnitTest < Minitest::Test
   end
 
   module LateAddedFilter
-    def late_added_filter(_input)
+    def late_added_filter(input)
       "filtered"
     end
   end
@@ -151,7 +150,7 @@ class StrainerUnitTest < Minitest::Test
     mod = Module.new do
       class << self
         attr_accessor :include_count
-        def included(_mod)
+        def included(mod)
           self.include_count += 1
         end
       end

test/unit/tag_unit_test.rb

@@ -18,42 +18,4 @@ class TagUnitTest < Minitest::Test
     tag = Tag.parse("some_tag", "", Tokenizer.new(""), ParseContext.new)
     assert_equal 'some_tag', tag.tag_name
   end
-
-  def test_custom_tags_have_a_default_render_to_output_buffer_method_for_backwards_compatibility
-    klass1 = Class.new(Tag) do
-      def render(*)
-        'hello'
-      end
-    end
-
-    with_custom_tag('blabla', klass1) do
-      template = Liquid::Template.parse("{% blabla %}")
-
-      assert_equal 'hello', template.render
-
-      buf = ''
-      output = template.render({}, output: buf)
-      assert_equal 'hello', output
-      assert_equal 'hello', buf
-      assert_equal buf.object_id, output.object_id
-    end
-
-    klass2 = Class.new(klass1) do
-      def render(*)
-        'foo' + super + 'bar'
-      end
-    end
-
-    with_custom_tag('blabla', klass2) do
-      template = Liquid::Template.parse("{% blabla %}")
-
-      assert_equal 'foohellobar', template.render
-
-      buf = ''
-      output = template.render({}, output: buf)
-      assert_equal 'foohellobar', output
-      assert_equal 'foohellobar', buf
-      assert_equal buf.object_id, output.object_id
-    end
-  end
 end

test/unit/tags/if_tag_unit_test.rb

@@ -3,6 +3,6 @@ require 'test_helper'
 class IfTagUnitTest < Minitest::Test
   def test_if_nodelist
     template = Liquid::Template.parse('{% if true %}IF{% else %}ELSE{% endif %}')
-    assert_equal(['IF', 'ELSE'], template.root.nodelist[0].nodelist.map(&:nodelist).flatten)
+    assert_equal ['IF', 'ELSE'], template.root.nodelist[0].nodelist.map(&:nodelist).flatten
   end
 end