Add support for iterating ranges with float boundaries.

The meaning I gave is to start at the lower bound and step by one. This has the advantage of having (n..m) and ((n.to_f)..(m.to_f)) behave the same. Another thing we could do that have this same property is to cast bounds to integer. This would do the right thing if there is a floating point rounding error, but I feel it is more surprising for cases such as (1.5..8). Note that it is not possible to create ranges with floating point boundaries directly in Liquid at the moment. However, since there is no distinction between Ruby and Liquid ranges, a drop can introduce such a value by returning it.
2026-01-02 00:05:42 +03:00 · 2017-08-09 12:13:00 -04:00
55 changed files with 378 additions and 1418 deletions
--- a/.github/probots.yml
+++ b/.github/probots.yml
@@ -1,2 +0,0 @@
-enabled:
-  - cla
--- a/.rubocop.yml
+++ b/.rubocop.yml
@@ -1,6 +1,4 @@
-inherit_from:
-  - .rubocop_todo.yml
-  - ./.rubocop_todo.yml
+inherit_from: ./.rubocop_todo.yml

 AllCops:
  Exclude:
@@ -9,6 +7,8 @@ AllCops:

 Metrics/BlockNesting:
  Max: 3
+  Exclude:
+    - 'lib/liquid/block_body.rb'

 Metrics/ModuleLength:
  Enabled: false
@@ -31,8 +31,8 @@ Lint/ParenthesesAsGroupedExpression:
 Lint/UnusedBlockArgument:
  Enabled: false

-Layout/EndAlignment:
-  EnforcedStyleAlignWith: variable
+Lint/EndAlignment:
+  AlignWith: variable

 Lint/UnusedMethodArgument:
  Enabled: false
@@ -61,10 +61,10 @@ Style/BracesAroundHashParameters:
 Style/NumericLiterals:
  Enabled: false

-Layout/SpaceInsideArrayLiteralBrackets:
+Style/SpaceInsideBrackets:
  Enabled: false

-Layout/SpaceBeforeBlockBraces:
+Style/SpaceBeforeBlockBraces:
  Enabled: false

 Style/Documentation:
@@ -73,22 +73,19 @@ Style/Documentation:
 Style/ClassAndModuleChildren:
  Enabled: false

-Style/TrailingCommaInArrayLiteral:
+Style/TrailingComma:
  Enabled: false

-Style/TrailingCommaInHashLiteral:
-  Enabled: false
-
-Layout/IndentHash:
+Style/IndentHash:
  EnforcedStyle: consistent

 Style/FormatString:
  Enabled: false

-Layout/AlignParameters:
+Style/AlignParameters:
  EnforcedStyle: with_fixed_indentation

-Layout/MultilineOperationIndentation:
+Style/MultilineOperationIndentation:
  EnforcedStyle: indented

 Style/IfUnlessModifier:
@@ -97,7 +94,7 @@ Style/IfUnlessModifier:
 Style/RaiseArgs:
  Enabled: false

-Style/PreferredHashMethods:
+Style/DeprecatedHashMethods:
  Enabled: false

 Style/RegexpLiteral:
@@ -109,10 +106,10 @@ Style/SymbolLiteral:
 Performance/Count:
  Enabled: false

-Naming/ConstantName:
+Style/ConstantName:
  Enabled: false

-Layout/CaseIndentation:
+Style/CaseIndentation:
  Enabled: false

 Style/ClassVars:
@@ -126,7 +123,3 @@ Style/TrivialAccessors:

 Style/WordArray:
  Enabled: false
-
-Naming/MethodName:
-  Exclude:
-    - 'example/server/liquid_servlet.rb'
--- a/.rubocop_todo.yml
+++ b/.rubocop_todo.yml
@@ -1,260 +1,72 @@
-# This configuration was generated by
-# `rubocop --auto-gen-config`
-# on 2019-03-19 11:04:37 -0400 using RuboCop version 0.53.0.
+# This configuration was generated by `rubocop --auto-gen-config`
+# on 2015-06-08 18:16:16 +0000 using RuboCop version 0.32.0.
 # The point is for the user to remove these configuration records
 # one by one as the offenses are removed from the code base.
 # Note that changes in the inspected code, or installation of new
 # versions of RuboCop, may require this file to be generated again.

-# Offense count: 1
-# Cop supports --auto-correct.
-# Configuration parameters: Include, TreatCommentsAsGroupSeparators.
-# Include: **/*.gemspec
-Gemspec/OrderedDependencies:
-  Exclude:
-    - 'liquid.gemspec'
-
 # Offense count: 5
-# Cop supports --auto-correct.
-# Configuration parameters: EnforcedStyle.
-# SupportedStyles: auto_detection, squiggly, active_support, powerpack, unindent
-Layout/IndentHeredoc:
-  Exclude:
-    - 'test/integration/tags/for_tag_test.rb'
-    - 'test/integration/trim_mode_test.rb'
+Lint/NestedMethodDefinition:
+  Enabled: false

-# Offense count: 6
-# Cop supports --auto-correct.
-# Configuration parameters: EnforcedStyle.
-# SupportedStyles: symmetrical, new_line, same_line
-Layout/MultilineMethodCallBraceLayout:
-  Exclude:
-    - 'test/integration/error_handling_test.rb'
-    - 'test/unit/strainer_unit_test.rb'
-
-# Offense count: 2
-# Cop supports --auto-correct.
-# Configuration parameters: EnforcedStyle.
-# SupportedStyles: runtime_error, standard_error
-Lint/InheritException:
-  Exclude:
-    - 'lib/liquid/interrupts.rb'
-
-# Offense count: 1
-# Configuration parameters: CheckForMethodsWithNoSideEffects.
-Lint/Void:
-  Exclude:
-    - 'lib/liquid/parse_context.rb'
-
-# Offense count: 54
+# Offense count: 53
 Metrics/AbcSize:
-  Max: 56
+  Max: 58

 # Offense count: 12
 Metrics/CyclomaticComplexity:
-  Max: 12
+  Max: 15

-# Offense count: 112
+# Offense count: 553
+# Configuration parameters: AllowURI, URISchemes.
+Metrics/LineLength:
+  Max: 294
+
+# Offense count: 77
 # Configuration parameters: CountComments.
 Metrics/MethodLength:
-  Max: 37
+  Max: 46

-# Offense count: 8
+# Offense count: 6
 Metrics/PerceivedComplexity:
-  Max: 11
+  Max: 13

-# Offense count: 52
-# Configuration parameters: Blacklist.
-# Blacklist: END, (?-mix:EO[A-Z]{1})
-Naming/HeredocDelimiterNaming:
-  Exclude:
-    - 'test/integration/assign_test.rb'
-    - 'test/integration/capture_test.rb'
-    - 'test/integration/trim_mode_test.rb'
-
-# Offense count: 23
-# Configuration parameters: MinNameLength, AllowNamesEndingInNumbers, AllowedNames, ForbiddenNames.
-# AllowedNames: io, id
-Naming/UncommunicativeMethodParamName:
-  Exclude:
-    - 'example/server/example_servlet.rb'
-    - 'lib/liquid/condition.rb'
-    - 'lib/liquid/context.rb'
-    - 'lib/liquid/standardfilters.rb'
-    - 'lib/liquid/tags/if.rb'
-    - 'lib/liquid/utils.rb'
-    - 'lib/liquid/variable.rb'
-    - 'test/integration/filter_test.rb'
-    - 'test/integration/standard_filter_test.rb'
-    - 'test/integration/tags/for_tag_test.rb'
-    - 'test/integration/template_test.rb'
-    - 'test/unit/condition_unit_test.rb'
-
-# Offense count: 10
-# Cop supports --auto-correct.
-# Configuration parameters: EnforcedStyle.
-# SupportedStyles: prefer_alias, prefer_alias_method
-Style/Alias:
-  Exclude:
-    - 'lib/liquid/drop.rb'
-    - 'lib/liquid/i18n.rb'
-    - 'lib/liquid/profiler/hooks.rb'
-    - 'lib/liquid/standardfilters.rb'
-    - 'lib/liquid/tag.rb'
-    - 'lib/liquid/tags/include.rb'
-    - 'lib/liquid/variable.rb'
-
-# Offense count: 22
-Style/CommentedKeyword:
+# Offense count: 1
+Style/AccessorMethodName:
  Enabled: false

 # Offense count: 1
 # Cop supports --auto-correct.
-# Configuration parameters: EnforcedStyle, SingleLineConditionsOnly, IncludeTernaryExpressions.
-# SupportedStyles: assign_to_condition, assign_inside_condition
-Style/ConditionalAssignment:
-  Exclude:
-    - 'lib/liquid/errors.rb'
-
-# Offense count: 1
-Style/DateTime:
-  Exclude:
-    - 'test/unit/context_unit_test.rb'
-
-# Offense count: 2
-# Cop supports --auto-correct.
-Style/EmptyCaseCondition:
-  Exclude:
-    - 'lib/liquid/block_body.rb'
-    - 'lib/liquid/lexer.rb'
-
-# Offense count: 5
-# Cop supports --auto-correct.
-# Configuration parameters: EnforcedStyle.
-# SupportedStyles: compact, expanded
-Style/EmptyMethod:
-  Exclude:
-    - 'lib/liquid/tag.rb'
-    - 'lib/liquid/tags/comment.rb'
-    - 'lib/liquid/tags/include.rb'
-    - 'test/integration/tags/include_tag_test.rb'
-    - 'test/unit/context_unit_test.rb'
+Style/ClosingParenthesisIndentation:
+  Enabled: false

 # 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'
+  Enabled: false

 # 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'
+# Configuration parameters: EnforcedStyle, SupportedStyles.
+Style/MethodName:
+  Enabled: false

 # Offense count: 1
-# Cop supports --auto-correct.
-Style/RedundantSelf:
-  Exclude:
-    - 'lib/liquid/strainer.rb'
+Style/MultilineBlockChain:
+  Enabled: false

-# Offense count: 9
+# Offense count: 2
+# Configuration parameters: EnforcedStyle, MinBodyLength, SupportedStyles.
+Style/Next:
+  Enabled: false
+
+# Offense count: 7
 # Cop supports --auto-correct.
 # Configuration parameters: AllowAsExpressionSeparator.
 Style/Semicolon:
-  Exclude:
-    - 'test/integration/error_handling_test.rb'
-    - 'test/integration/template_test.rb'
-    - 'test/unit/context_unit_test.rb'
-
-# Offense count: 7
-# Cop supports --auto-correct.
-# Configuration parameters: MinSize.
-# SupportedStyles: percent, brackets
-Style/SymbolArray:
-  EnforcedStyle: brackets
-
-# Offense count: 2
-# Cop supports --auto-correct.
-# Configuration parameters: EnforcedStyle, AllowSafeAssignment.
-# SupportedStyles: require_parentheses, require_no_parentheses, require_parentheses_when_complex
-Style/TernaryParentheses:
-  Exclude:
-    - 'lib/liquid/context.rb'
-    - 'lib/liquid/utils.rb'
-
-# Offense count: 2
-# Cop supports --auto-correct.
-Style/UnneededPercentQ:
-  Exclude:
-    - 'test/integration/error_handling_test.rb'
+  Enabled: false

 # Offense count: 1
 # Cop supports --auto-correct.
+# Configuration parameters: MaxLineLength.
 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
+  Enabled: false
--- a/.travis.yml
+++ b/.travis.yml
@@ -3,9 +3,7 @@ language: ruby
 rvm:
  - 2.1
  - 2.2
-  - 2.3
-  - 2.4
-  - 2.5
+  - 2.3.3
  - ruby-head
  - jruby-head
 #  - rbx-2
@@ -19,13 +17,13 @@ addons:

 matrix:
  allow_failures:
-    - rvm: ruby-head
    - rvm: jruby-head

 install:
+  - gem install rainbow -v 2.2.1
  - bundle install

-script: bundle exec rake
+script: "bundle exec rake"

 notifications:
  disable: true
--- a/14
+++ b/14
@@ -1,23 +1,17 @@
 source 'https://rubygems.org'
-git_source(:github) do |repo_name|
-  "https://github.com/#{repo_name}.git"
-end

 gemspec

+gem 'stackprof', platforms: :mri
+
 group :benchmark, :test do
  gem 'benchmark-ips'
-  gem 'memory_profiler'
-
-  install_if -> { RUBY_PLATFORM !~ /mingw|mswin|java/ } do
-    gem 'stackprof'
-  end
 end

 group :test do
-  gem 'rubocop', '~> 0.53.0'
+  gem 'rubocop', '0.34.2'

  platform :mri do
-    gem 'liquid-c', github: 'Shopify/liquid-c', ref: '9168659de45d6d576fce30c735f857e597fa26f6'
+    gem 'liquid-c', github: 'Shopify/liquid-c', ref: 'bd53db95de3d44d631e7c5a267c3d934e66107dd'
  end
 end
--- a/History.md
+++ b/History.md
@@ -1,58 +1,5 @@
 # Liquid Change Log

-## 4.0.3 / 2019-03-12
-
-### Fixed
-* Fix break and continue tags inside included templates in loops (#1072) [Justin Li]
-
-## 4.0.2 / 2019-03-08
-
-### Changed
-* Add `where` filter (#1026) [Samuel Doiron]
-* Add `ParseTreeVisitor` to iterate the Liquid AST (#1025) [Stephen Paul Weber]
-* Improve `strip_html` performance (#1032) [printercu]
-
-### Fixed
-* Add error checking for invalid combinations of inputs to sort, sort_natural, where, uniq, map, compact filters (#1059) [Garland Zhang]
-* Validate the character encoding in url_decode (#1070) [Clayton Smith]
-
-## 4.0.1 / 2018-10-09
-
-### Changed
-* Add benchmark group in Gemfile (#855) [Jerry Liu]
-* Allow benchmarks to benchmark render by itself (#851) [Jerry Liu]
-* Avoid calling `line_number` on String node when rescuing a render error. (#860) [Dylan Thacker-Smith]
-* Avoid duck typing to detect whether to call render on a node. [Dylan Thacker-Smith]
-* Clarify spelling of `reversed` on `for` block tag (#843) [Mark Crossfield]
-* Replace recursion with loop to avoid potential stack overflow from malicious input (#891, #892) [Dylan Thacker-Smith]
-* Limit block tag nesting to 100 (#894) [Dylan Thacker-Smith]
-* Replace `assert_equal nil` with `assert_nil` (#895) [Dylan Thacker-Smith]
-* Remove Spy Gem (#896) [Dylan Thacker-Smith]
-* Add `collection_name` and `variable_name` reader to `For` block (#909)
-* Symbols render as strings (#920) [Justin Li]
-* Remove default value from Hash objects (#932) [Maxime Bedard]
-* Remove one level of nesting (#944) [Dylan Thacker-Smith]
-* Update Rubocop version (#952) [Justin Li]
-* Add `at_least` and `at_most` filters (#954, #958) [Nithin Bekal]
-* Add a regression test for a liquid-c trim mode bug (#972) [Dylan Thacker-Smith]
-* Use https rather than git protocol to fetch liquid-c [Dylan Thacker-Smith]
-* Add tests against Ruby 2.4 (#963) and 2.5 (#981)
-* Replace RegExp literals with constants (#988) [Ashwin Maroli]
-* Replace unnecessary `#each_with_index` with `#each` (#992) [Ashwin Maroli]
-* Improve the unexpected end delimiter message for block tags. (#1003) [Dylan Thacker-Smith]
-* Refactor and optimize rendering (#1005) [Christopher Aue]
-* Add installation instruction (#1006) [Ben Gift]
-* Remove Circle CI (#1010)
-* Rename deprecated `BigDecimal.new` to `BigDecimal` (#1024) [Koichi ITO]
-* Rename deprecated Rubocop name (#1027) [Justin Li]
-
-### Fixed
-* Handle `join` filter on non String joiners (#857) [Richard Monette]
-* Fix duplicate inclusion condition logic error of `Liquid::Strainer.add_filter` method (#861)
-* Fix `escape`, `url_encode`, `url_decode` not handling non-string values (#898) [Thierry Joyal]
-* Fix raise when variable is defined but nil when using `strict_variables` [Pascal Betz]
-* Fix `sort` and `sort_natural` to handle arrays with nils (#930) [Eric Chan]
-
 ## 4.0.0 / 2016-12-14 / branch "4-0-stable"

 ### Changed
--- a/README.md
+++ b/README.md
@@ -42,8 +42,6 @@ Liquid is a template engine which was written with very specific requirements:

 ## How to use Liquid

-Install Liquid by adding `gem 'liquid'` to your gemfile.
-
 Liquid supports a very simple API based around the Liquid::Template class.
 For standard use you can just pass it the content of a file and call render with a parameters hash.

--- a/9
+++ b/9
@@ -3,7 +3,7 @@ require 'rake/testtask'
 $LOAD_PATH.unshift File.expand_path("../lib", __FILE__)
 require "liquid/version"

-task default: [:test, :rubocop]
+task default: [:rubocop, :test]

 desc 'run test suite with default parser'
 Rake::TestTask.new(:base_test) do |t|
@@ -85,13 +85,6 @@ namespace :profile do
  end
 end

-namespace :memory_profile do
-  desc "Run memory profiler"
-  task :run do
-    ruby "./performance/memory_profile.rb"
-  end
-end
-
 desc "Run example"
 task :example do
  ruby "-w -d -Ilib example/server/server.rb"
--- a/circle.yml
+++ b/circle.yml
@@ -0,0 +1,3 @@
+machine:
+  ruby:
+    version: ruby-2.1
--- a/lib/liquid.rb
+++ b/lib/liquid.rb
@@ -45,7 +45,6 @@ module Liquid
 end

 require "liquid/version"
-require 'liquid/parse_tree_visitor'
 require 'liquid/lexer'
 require 'liquid/parser'
 require 'liquid/i18n'
--- a/lib/liquid/block.rb
+++ b/lib/liquid/block.rb
@@ -26,12 +26,12 @@ module Liquid
    end

    def unknown_tag(tag, _params, _tokens)
-      if tag == 'else'.freeze
+      case tag
+      when 'else'.freeze
        raise SyntaxError.new(parse_context.locale.t("errors.syntax.unexpected_else".freeze,
          block_name: block_name))
-      elsif tag.start_with?('end'.freeze)
+      when 'end'.freeze
        raise SyntaxError.new(parse_context.locale.t("errors.syntax.invalid_delimiter".freeze,
-          tag: tag,
          block_name: block_name,
          block_delimiter: block_delimiter))
      else
--- a/lib/liquid/block_body.rb
+++ b/lib/liquid/block_body.rb
@@ -2,7 +2,6 @@ module Liquid
  class BlockBody
    FullToken = /\A#{TagStart}#{WhitespaceControl}?\s*(\w+)\s*(.*?)#{WhitespaceControl}?#{TagEnd}\z/om
    ContentOfVariable = /\A#{VariableStart}#{WhitespaceControl}?(.*?)#{WhitespaceControl}?#{VariableEnd}\z/om
-    WhitespaceOrNothing = /\A\s*\z/
    TAGSTART = "{%".freeze
    VARSTART = "{{".freeze

@@ -16,35 +15,38 @@ module Liquid
    def parse(tokenizer, parse_context)
      parse_context.line_number = tokenizer.line_number
      while token = tokenizer.shift
-        next if token.empty?
-        case
-        when token.start_with?(TAGSTART)
-          whitespace_handler(token, parse_context)
-          unless token =~ FullToken
-            raise_missing_tag_terminator(token, parse_context)
+        unless token.empty?
+          case
+          when token.start_with?(TAGSTART)
+            whitespace_handler(token, parse_context)
+            if token =~ FullToken
+              tag_name = $1
+              markup = $2
+              # fetch the tag from registered blocks
+              if tag = registered_tags[tag_name]
+                new_tag = tag.parse(tag_name, markup, tokenizer, parse_context)
+                @blank &&= new_tag.blank?
+                @nodelist << new_tag
+              else
+                # end parsing if we reach an unknown tag and let the caller decide
+                # determine how to proceed
+                return yield tag_name, markup
+              end
+            else
+              raise_missing_tag_terminator(token, parse_context)
+            end
+          when token.start_with?(VARSTART)
+            whitespace_handler(token, parse_context)
+            @nodelist << create_variable(token, parse_context)
+            @blank = false
+          else
+            if parse_context.trim_whitespace
+              token.lstrip!
+            end
+            parse_context.trim_whitespace = false
+            @nodelist << token
+            @blank &&= !!(token =~ /\A\s*\z/)
          end
-          tag_name = $1
-          markup = $2
-          # fetch the tag from registered blocks
-          unless tag = registered_tags[tag_name]
-            # end parsing if we reach an unknown tag and let the caller decide
-            # determine how to proceed
-            return yield tag_name, markup
-          end
-          new_tag = tag.parse(tag_name, markup, tokenizer, parse_context)
-          @blank &&= new_tag.blank?
-          @nodelist << new_tag
-        when token.start_with?(VARSTART)
-          whitespace_handler(token, parse_context)
-          @nodelist << create_variable(token, parse_context)
-          @blank = false
-        else
-          if parse_context.trim_whitespace
-            token.lstrip!
-          end
-          parse_context.trim_whitespace = false
-          @nodelist << token
-          @blank &&= !!(token =~ WhitespaceOrNothing)
        end
        parse_context.line_number = tokenizer.line_number
      end
@@ -70,28 +72,33 @@ module Liquid
      output = []
      context.resource_limits.render_score += @nodelist.length

-      idx = 0
-      while node = @nodelist[idx]
-        case node
-        when String
-          check_resources(context, node)
-          output << node
-        when Variable
-          render_node_to_output(node, output, context)
-        when Block
-          render_node_to_output(node, output, context, node.blank?)
-          break if context.interrupt? # might have happened in a for-block
-        when Continue, Break
+      @nodelist.each do |token|
+        # Break out if we have any unhanded interrupts.
+        break if context.interrupt?
+
+        begin
          # If we get an Interrupt that means the block must stop processing. An
          # Interrupt is any command that stops block execution such as {% break %}
          # or {% continue %}
-          context.push_interrupt(node.interrupt)
-          break
-        else # Other non-Block tags
-          render_node_to_output(node, output, context)
-          break if context.interrupt? # might have happened through an include
+          if token.is_a?(Continue) || token.is_a?(Break)
+            context.push_interrupt(token.interrupt)
+            break
+          end
+
+          node_output = render_node(token, context)
+
+          unless token.is_a?(Block) && token.blank?
+            output << node_output
+          end
+        rescue MemoryError => e
+          raise e
+        rescue UndefinedVariable, UndefinedDropMethod, UndefinedFilter => e
+          context.handle_error(e, token.line_number)
+          output << nil
+        rescue ::StandardError => e
+          line_number = token.is_a?(String) ? nil : token.line_number
+          output << context.handle_error(e, line_number)
        end
-        idx += 1
      end

      output.join
@@ -99,25 +106,15 @@ module Liquid

    private

-    def render_node_to_output(node, output, context, skip_output = false)
-      node_output = node.render(context)
+    def render_node(node, context)
+      node_output = node.is_a?(String) ? node : node.render(context)
      node_output = node_output.is_a?(Array) ? node_output.join : node_output.to_s
-      check_resources(context, node_output)
-      output << node_output unless skip_output
-    rescue MemoryError => e
-      raise e
-    rescue UndefinedVariable, UndefinedDropMethod, UndefinedFilter => e
-      context.handle_error(e, node.line_number)
-      output << nil
-    rescue ::StandardError => e
-      line_number = node.is_a?(String) ? nil : node.line_number
-      output << context.handle_error(e, line_number)
-    end

-    def check_resources(context, node_output)
-      context.resource_limits.render_length += node_output.bytesize
-      return unless context.resource_limits.reached?
-      raise MemoryError.new("Memory limits exceeded".freeze)
+      context.resource_limits.render_length += node_output.length
+      if context.resource_limits.reached?
+        raise MemoryError.new("Memory limits exceeded".freeze)
+      end
+      node_output
    end

    def create_variable(token, parse_context)
--- a/lib/liquid/condition.rb
+++ b/lib/liquid/condition.rb
@@ -29,7 +29,7 @@ module Liquid
      @@operators
    end

-    attr_reader :attachment, :child_condition
+    attr_reader :attachment
    attr_accessor :left, :operator, :right

    def initialize(left = nil, operator = nil, right = nil)
@@ -83,7 +83,7 @@ module Liquid

    protected

-    attr_reader :child_relation
+    attr_reader :child_relation, :child_condition

    private

@@ -128,15 +128,6 @@ module Liquid
        end
      end
    end
-
-    class ParseTreeVisitor < Liquid::ParseTreeVisitor
-      def children
-        [
-          @node.left, @node.right,
-          @node.child_condition, @node.attachment
-        ].compact
-      end
-    end
  end

  class ElseCondition < Condition
--- a/lib/liquid/context.rb
+++ b/lib/liquid/context.rb
@@ -12,12 +12,12 @@ module Liquid
  #
  #   context['bob']  #=> nil  class Context
  class Context
-    attr_reader :scope, :errors, :registers, :environments, :resource_limits
+    attr_reader :scopes, :errors, :registers, :environments, :resource_limits
    attr_accessor :exception_renderer, :template_name, :partial, :global_filter, :strict_variables, :strict_filters

    def initialize(environments = {}, outer_scope = {}, registers = {}, rethrow_errors = false, resource_limits = nil)
      @environments     = [environments].flatten
-      @scope            = outer_scope || {}
+      @scopes           = [(outer_scope || {})]
      @registers        = registers
      @errors           = []
      @partial          = false
@@ -25,6 +25,8 @@ module Liquid
      @resource_limits  = resource_limits || ResourceLimits.new(Template.default_resource_limits)
      squash_instance_assigns_with_environments

+      @this_stack_used = false
+
      self.exception_renderer = Template.default_exception_renderer
      if rethrow_errors
        self.exception_renderer = ->(e) { raise }
@@ -33,8 +35,6 @@ module Liquid
      @interrupts = []
      @filters = []
      @global_filter = nil
-
-      @stack_level = 0
    end

    def warnings
@@ -86,9 +86,21 @@ module Liquid
      strainer.invoke(method, *args).to_liquid
    end

+    # Push new local scope on the stack. use <tt>Context#stack</tt> instead
+    def push(new_scope = {})
+      @scopes.unshift(new_scope)
+      raise StackLevelError, "Nesting too deep".freeze if @scopes.length > Block::MAX_DEPTH
+    end
+
    # Merge a hash of variables in the current local scope
    def merge(new_scopes)
-      new_scopes.each { |k, v| self[k] = v }
+      @scopes[0].merge!(new_scopes)
+    end
+
+    # Pop from the stack. use <tt>Context#stack</tt> instead
+    def pop
+      raise ContextError if @scopes.size == 1
+      @scopes.shift
    end

    # Pushes a new local scope on the stack, pops it at the end of the block
@@ -99,20 +111,32 @@ module Liquid
    #   end
    #
    #   context['var]  #=> nil
-    def stack(*variable_names)
-      @stack_level += 1
-      raise StackLevelError, "Nesting too deep".freeze if @stack_level > Block::MAX_DEPTH
-
-      begin
-        yield
-      ensure
-        @stack_level -= 1
+    def stack(new_scope = nil)
+      old_stack_used = @this_stack_used
+      if new_scope
+        push(new_scope)
+        @this_stack_used = true
+      else
+        @this_stack_used = false
      end
+
+      yield
+    ensure
+      pop if @this_stack_used
+      @this_stack_used = old_stack_used
+    end
+
+    def clear_instance_assigns
+      @scopes[0] = {}
    end

    # Only allow String, Numeric, Hash, Array, Proc, Boolean or <tt>Liquid::Drop</tt>
    def []=(key, value)
-      (@scope[key] ||= [nil]) << value
+      unless @this_stack_used
+        @this_stack_used = true
+        push({})
+      end
+      @scopes[0][key] = value
    end

    # Look up variable, either resolve directly after considering the name. We can directly handle
@@ -127,29 +151,6 @@ module Liquid
      evaluate(Expression.parse(expression))
    end

-    def unset(key)
-      if @scope[key].size <= 1
-        @scope.delete(key)
-      else
-        @scope[key].pop
-      end
-    end
-
-    def set_root(key, val)
-      @scope[key] ||= []
-      @scope[key][0] = val
-    end
-
-    def set_level(key, val, int)
-      @scope[key] ||= []
-      @scope[key][int] = val
-    end
-
-    def create_level(key)
-      (@scope[key] ||= [nil]) << nil
-      @scope[key].size - 1
-    end
-
    def key?(key)
      self[key] != nil
    end
@@ -160,23 +161,25 @@ module Liquid

    # Fetches an object starting at the local scope and then moving up the hierachy
    def find_variable(key, raise_on_not_found: true)
-      trigger = false
-      value = @scope[key]
-      scope = @scope unless value.nil?
-      trigger = true unless value.nil?
+      # 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 = nil

      if scope.nil?
-        index = @environments.find_index do |e|
+        @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.
-          !variable.nil? || @strict_variables && raise_on_not_found
+          unless variable.nil?
+            scope = e
+            break
+          end
        end
-
-        scope = @environments[index || -1]
      end

-      variable ||= lookup_and_evaluate(scope, key, trigger, raise_on_not_found: raise_on_not_found)
+      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=)
@@ -184,16 +187,12 @@ module Liquid
      variable
    end

-    def lookup_and_evaluate(obj, key, trigger = false, raise_on_not_found: true)
+    def lookup_and_evaluate(obj, key, raise_on_not_found: true)
      if @strict_variables && raise_on_not_found && obj.respond_to?(:key?) && !obj.key?(key)
        raise Liquid::UndefinedVariable, "undefined variable #{key}"
      end

-      value = if trigger == true
-        obj[key][-1]
-      else
-        obj[key]
-      end
+      value = obj[key]

      if value.is_a?(Proc) && obj.respond_to?(:[]=)
        obj[key] = (value.arity == 0) ? value.call : value.call(self)
@@ -212,10 +211,10 @@ module Liquid
    end

    def squash_instance_assigns_with_environments
-      @scope.each_key do |k|
+      @scopes.last.each_key do |k|
        @environments.each do |env|
          if env.key?(k)
-            @scope[k] = [lookup_and_evaluate(env, k)]
+            scopes.last[k] = lookup_and_evaluate(env, k)
            break
          end
        end
--- a/lib/liquid/expression.rb
+++ b/lib/liquid/expression.rb
@@ -19,26 +19,22 @@ module Liquid
      'false'.freeze => false,
      'blank'.freeze => MethodLiteral.new(:blank?, '').freeze,
      'empty'.freeze => MethodLiteral.new(:empty?, '').freeze
-    }.freeze
-
-    SINGLE_QUOTED_STRING = /\A'(.*)'\z/m
-    DOUBLE_QUOTED_STRING = /\A"(.*)"\z/m
-    INTEGERS_REGEX       = /\A(-?\d+)\z/
-    FLOATS_REGEX         = /\A(-?\d[\d\.]+)\z/
-    RANGES_REGEX         = /\A\((\S+)\.\.(\S+)\)\z/
+    }

    def self.parse(markup)
      if LITERALS.key?(markup)
        LITERALS[markup]
      else
        case markup
-        when SINGLE_QUOTED_STRING, DOUBLE_QUOTED_STRING
+        when /\A'(.*)'\z/m # Single quoted strings
          $1
-        when INTEGERS_REGEX
+        when /\A"(.*)"\z/m # Double quoted strings
+          $1
+        when /\A(-?\d+)\z/ # Integer and floats
          $1.to_i
-        when RANGES_REGEX
+        when /\A\((\S+)\.\.(\S+)\)\z/ # Ranges
          RangeLookup.parse($1, $2)
-        when FLOATS_REGEX
+        when /\A(-?\d[\d\.]+)\z/ # Floats
          $1.to_f
        else
          VariableLookup.parse(markup)
--- a/lib/liquid/extensions.rb
+++ b/lib/liquid/extensions.rb
@@ -7,12 +7,6 @@ class String # :nodoc:
  end
 end

-class Symbol # :nodoc:
-  def to_liquid
-    to_s
-  end
-end
-
 class Array # :nodoc:
  def to_liquid
    self
--- a/lib/liquid/i18n.rb
+++ b/lib/liquid/i18n.rb
@@ -26,7 +26,7 @@ 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[$1.to_sym]).to_s
+        "#{vars[$1.to_sym]}"
      end
    end

--- a/lib/liquid/lexer.rb
+++ b/lib/liquid/lexer.rb
@@ -12,14 +12,13 @@ module Liquid
      ')'.freeze => :close_round,
      '?'.freeze => :question,
      '-'.freeze => :dash
-    }.freeze
+    }
    IDENTIFIER = /[a-zA-Z_][\w-]*\??/
    SINGLE_STRING_LITERAL = /'[^\']*'/
    DOUBLE_STRING_LITERAL = /"[^\"]*"/
    NUMBER_LITERAL = /-?\d+(\.\d+)?/
    DOTDOT = /\.\./
    COMPARISON_OPERATOR = /==|!=|<>|<=?|>=?|contains(?=\s)/
-    WHITESPACE_OR_NOTHING = /\s*/

    def initialize(input)
      @ss = StringScanner.new(input)
@@ -29,7 +28,7 @@ module Liquid
      @output = []

      until @ss.eos?
-        @ss.skip(WHITESPACE_OR_NOTHING)
+        @ss.skip(/\s*/)
        break if @ss.eos?
        tok = case
        when t = @ss.scan(COMPARISON_OPERATOR) then [:comparison, t]
--- a/lib/liquid/locales/en.yml
+++ b/lib/liquid/locales/en.yml
@@ -14,7 +14,7 @@
      if: "Syntax Error in tag 'if' - Valid syntax: if [expression]"
      include: "Error in tag 'include' - Valid syntax: include '[template]' (with|for) [object|collection]"
      unknown_tag: "Unknown tag '%{tag}'"
-      invalid_delimiter: "'%{tag}' is not a valid delimiter for %{block_name} tags. use %{block_delimiter}"
+      invalid_delimiter: "'end' is not a valid delimiter for %{block_name} tags. use %{block_delimiter}"
      unexpected_else: "%{block_name} tag does not expect 'else' tag"
      unexpected_outer_tag: "Unexpected outer '%{tag}' tag"
      tag_termination: "Tag '%{token}' was not properly terminated with regexp: %{tag_end}"
--- a/lib/liquid/parse_tree_visitor.rb
+++ b/lib/liquid/parse_tree_visitor.rb
@@ -1,42 +0,0 @@
-# frozen_string_literal: true
-
-module Liquid
-  class ParseTreeVisitor
-    def self.for(node, callbacks = Hash.new(proc {}))
-      if defined?(node.class::ParseTreeVisitor)
-        node.class::ParseTreeVisitor
-      else
-        self
-      end.new(node, callbacks)
-    end
-
-    def initialize(node, callbacks)
-      @node = node
-      @callbacks = callbacks
-    end
-
-    def add_callback_for(*classes, &block)
-      callback = block
-      callback = ->(node, _) { yield node } if block.arity.abs == 1
-      callback = ->(_, _) { yield } if block.arity.zero?
-      classes.each { |klass| @callbacks[klass] = callback }
-      self
-    end
-
-    def visit(context = nil)
-      children.map do |node|
-        item, new_context = @callbacks[node.class].call(node, context)
-        [
-          item,
-          ParseTreeVisitor.for(node, @callbacks).visit(new_context || context)
-        ]
-      end
-    end
-
-    protected
-
-    def children
-      @node.respond_to?(:nodelist) ? Array(@node.nodelist) : []
-    end
-  end
-end
--- a/lib/liquid/profiler/hooks.rb
+++ b/lib/liquid/profiler/hooks.rb
@@ -1,13 +1,13 @@
 module Liquid
  class BlockBody
-    def render_node_with_profiling(node, output, context, skip_output = false)
+    def render_node_with_profiling(node, context)
      Profiler.profile_node_render(node) do
-        render_node_without_profiling(node, output, context, skip_output)
+        render_node_without_profiling(node, context)
      end
    end

-    alias_method :render_node_without_profiling, :render_node_to_output
-    alias_method :render_node_to_output, :render_node_with_profiling
+    alias_method :render_node_without_profiling, :render_node
+    alias_method :render_node, :render_node_with_profiling
  end

  class Include < Tag
--- a/lib/liquid/standardfilters.rb
+++ b/lib/liquid/standardfilters.rb
@@ -9,14 +9,8 @@ module Liquid
      '<'.freeze => '&lt;'.freeze,
      '"'.freeze => '&quot;'.freeze,
      "'".freeze => '&#39;'.freeze
-    }.freeze
+    }
    HTML_ESCAPE_ONCE_REGEXP = /["><']|&(?!([a-zA-Z]+|(#\d+));)/
-    STRIP_HTML_BLOCKS = Regexp.union(
-      /<script.*?<\/script>/m,
-      /<!--.*?-->/m,
-      /<style.*?<\/style>/m
-    )
-    STRIP_HTML_TAGS = /<.*?>/m

    # Return the size of an array or of an string
    def size(input)
@@ -52,12 +46,7 @@ module Liquid
    end

    def url_decode(input)
-      return if input.nil?
-
-      result = CGI.unescape(input.to_s)
-      raise Liquid::ArgumentError, "invalid byte sequence in #{result.encoding}" unless result.valid_encoding?
-
-      result
+      CGI.unescape(input.to_s) unless input.nil?
    end

    def slice(input, offset, length = nil)
@@ -114,9 +103,7 @@ module Liquid

    def strip_html(input)
      empty = ''.freeze
-      result = input.to_s.gsub(STRIP_HTML_BLOCKS, empty)
-      result.gsub!(STRIP_HTML_TAGS, empty)
-      result
+      input.to_s.gsub(/<script.*?<\/script>/m, empty).gsub(/<!--.*?-->/m, empty).gsub(/<style.*?<\/style>/m, empty).gsub(/<.*?>/m, empty)
    end

    # Remove all newlines from the string
@@ -133,18 +120,19 @@ module Liquid
    # provide optional property with which to sort an array of hashes or drops
    def sort(input, property = nil)
      ary = InputIterator.new(input)
-
-      return [] if ary.empty?
-
      if property.nil?
+        ary.sort
+      elsif ary.empty? # The next two cases assume a non-empty array.
+        []
+      elsif ary.first.respond_to?(:[]) && !ary.first[property].nil?
        ary.sort do |a, b|
-          nil_safe_compare(a, b)
-        end
-      elsif ary.all? { |el| el.respond_to?(:[]) }
-        begin
-          ary.sort { |a, b| nil_safe_compare(a[property], b[property]) }
-        rescue TypeError
-          raise_property_error(property)
+          a = a[property]
+          b = b[property]
+          if a && b
+            a <=> b
+          else
+            a ? -1 : 1
+          end
        end
      end
    end
@@ -154,40 +142,12 @@ module Liquid
    def sort_natural(input, property = nil)
      ary = InputIterator.new(input)

-      return [] if ary.empty?
-
      if property.nil?
-        ary.sort do |a, b|
-          nil_safe_casecmp(a, b)
-        end
-      elsif ary.all? { |el| el.respond_to?(:[]) }
-        begin
-          ary.sort { |a, b| nil_safe_casecmp(a[property], b[property]) }
-        rescue TypeError
-          raise_property_error(property)
-        end
-      end
-    end
-
-    # Filter the elements of an array to those with a certain property value.
-    # By default the target is any truthy value.
-    def where(input, property, target_value = nil)
-      ary = InputIterator.new(input)
-
-      if ary.empty?
+        ary.sort { |a, b| a.casecmp(b) }
+      elsif ary.empty? # The next two cases assume a non-empty array.
        []
-      elsif ary.first.respond_to?(:[]) && target_value.nil?
-        begin
-          ary.select { |item| item[property] }
-        rescue TypeError
-          raise_property_error(property)
-        end
-      elsif ary.first.respond_to?(:[])
-        begin
-          ary.select { |item| item[property] == target_value }
-        rescue TypeError
-          raise_property_error(property)
-        end
+      elsif ary.first.respond_to?(:[]) && !ary.first[property].nil?
+        ary.sort { |a, b| a[property].casecmp(b[property]) }
      end
    end

@@ -201,11 +161,7 @@ module Liquid
      elsif ary.empty? # The next two cases assume a non-empty array.
        []
      elsif ary.first.respond_to?(:[])
-        begin
-          ary.uniq { |a| a[property] }
-        rescue TypeError
-          raise_property_error(property)
-        end
+        ary.uniq{ |a| a[property] }
      end
    end

@@ -227,8 +183,6 @@ module Liquid
          r.is_a?(Proc) ? r.call : r
        end
      end
-    rescue TypeError
-      raise_property_error(property)
    end

    # Remove nils within an array
@@ -241,11 +195,7 @@ module Liquid
      elsif ary.empty? # The next two cases assume a non-empty array.
        []
      elsif ary.first.respond_to?(:[])
-        begin
-          ary.reject { |a| a[property].nil? }
-        rescue TypeError
-          raise_property_error(property)
-        end
+        ary.reject{ |a| a[property].nil? }
      end
    end

@@ -403,22 +353,6 @@ module Liquid
      raise Liquid::FloatDomainError, e.message
    end

-    def at_least(input, n)
-      min_value = Utils.to_number(n)
-
-      result = Utils.to_number(input)
-      result = min_value if min_value > result
-      result.is_a?(BigDecimal) ? result.to_f : result
-    end
-
-    def at_most(input, n)
-      max_value = Utils.to_number(n)
-
-      result = Utils.to_number(input)
-      result = max_value if max_value < result
-      result.is_a?(BigDecimal) ? result.to_f : result
-    end
-
    def default(input, default_value = ''.freeze)
      if !input || input.respond_to?(:empty?) && input.empty?
        default_value
@@ -429,31 +363,11 @@ module Liquid

    private

-    def raise_property_error(property)
-      raise Liquid::ArgumentError.new("cannot select the property '#{property}'")
-    end
-
    def apply_operation(input, operand, operation)
      result = Utils.to_number(input).send(operation, Utils.to_number(operand))
      result.is_a?(BigDecimal) ? result.to_f : result
    end

-    def nil_safe_compare(a, b)
-      if !a.nil? && !b.nil?
-        a <=> b
-      else
-        a.nil? ? 1 : -1
-      end
-    end
-
-    def nil_safe_casecmp(a, b)
-      if !a.nil? && !b.nil?
-        a.to_s.casecmp(b.to_s)
-      else
-        a.nil? ? 1 : -1
-      end
-    end
-
    class InputIterator
      include Enumerable

--- a/lib/liquid/tags/assign.rb
+++ b/lib/liquid/tags/assign.rb
@@ -10,8 +10,6 @@ module Liquid
  class Assign < Tag
    Syntax = /(#{VariableSignature}+)\s*=\s*(.*)\s*/om

-    attr_reader :to, :from
-
    def initialize(tag_name, markup, options)
      super
      if markup =~ Syntax
@@ -24,7 +22,7 @@ module Liquid

    def render(context)
      val = @from.render(context)
-      context.set_root(@to, val)
+      context.scopes.last[@to] = val
      context.resource_limits.assign_score += assign_score_of(val)
      ''.freeze
    end
@@ -37,7 +35,7 @@ module Liquid

    def assign_score_of(val)
      if val.instance_of?(String)
-        val.bytesize
+        val.length
      elsif val.instance_of?(Array) || val.instance_of?(Hash)
        sum = 1
        # Uses #each to avoid extra allocations.
@@ -47,12 +45,6 @@ module Liquid
        1
      end
    end
-
-    class ParseTreeVisitor < Liquid::ParseTreeVisitor
-      def children
-        [@node.from]
-      end
-    end
  end

  Template.register_tag('assign'.freeze, Assign)
--- a/lib/liquid/tags/capture.rb
+++ b/lib/liquid/tags/capture.rb
@@ -24,8 +24,8 @@ module Liquid

    def render(context)
      output = super
-      context.set_root(@to, output)
-      context.resource_limits.assign_score += output.bytesize
+      context.scopes.last[@to] = output
+      context.resource_limits.assign_score += output.length
      ''.freeze
    end

--- a/lib/liquid/tags/case.rb
+++ b/lib/liquid/tags/case.rb
@@ -3,8 +3,6 @@ module Liquid
    Syntax     = /(#{QuotedFragment})/o
    WhenSyntax = /(#{QuotedFragment})(?:(?:\s+or\s+|\s*\,\s*)(#{QuotedFragment}.*))?/om

-    attr_reader :blocks, :left
-
    def initialize(tag_name, markup, options)
      super
      @blocks = []
@@ -39,19 +37,20 @@ module Liquid
    end

    def render(context)
-      execute_else_block = true
+      context.stack do
+        execute_else_block = true

-      output = ''
-      @blocks.each do |block|
-        if block.else?
-          return block.attachment.render(context) if execute_else_block
-        elsif block.evaluate(context)
-          execute_else_block = false
-          output << block.attachment.render(context)
+        output = ''
+        @blocks.each do |block|
+          if block.else?
+            return block.attachment.render(context) if execute_else_block
+          elsif block.evaluate(context)
+            execute_else_block = false
+            output << block.attachment.render(context)
+          end
        end
+        output
      end
-
-      output
    end

    private
@@ -81,12 +80,6 @@ module Liquid
      block.attach(BlockBody.new)
      @blocks << block
    end
-
-    class ParseTreeVisitor < Liquid::ParseTreeVisitor
-      def children
-        [@node.left] + @node.blocks
-      end
-    end
  end

  Template.register_tag('case'.freeze, Case)
--- a/lib/liquid/tags/cycle.rb
+++ b/lib/liquid/tags/cycle.rb
@@ -15,8 +15,6 @@ module Liquid
    SimpleSyntax = /\A#{QuotedFragment}+/o
    NamedSyntax  = /\A(#{QuotedFragment})\s*\:\s*(.*)/om

-    attr_reader :variables
-
    def initialize(tag_name, markup, options)
      super
      case markup
@@ -32,15 +30,17 @@ module Liquid
    end

    def render(context)
-      context.registers[:cycle] ||= {}
+      context.registers[:cycle] ||= Hash.new(0)

-      key = context.evaluate(@name)
-      iteration = context.registers[:cycle][key].to_i
-      result = context.evaluate(@variables[iteration])
-      iteration += 1
-      iteration  = 0 if iteration >= @variables.size
-      context.registers[:cycle][key] = iteration
-      result
+      context.stack do
+        key = context.evaluate(@name)
+        iteration = context.registers[:cycle][key]
+        result = context.evaluate(@variables[iteration])
+        iteration += 1
+        iteration  = 0 if iteration >= @variables.size
+        context.registers[:cycle][key] = iteration
+        result
+      end
    end

    private
@@ -51,12 +51,6 @@ module Liquid
        $1 ? Expression.parse($1) : nil
      end.compact
    end
-
-    class ParseTreeVisitor < Liquid::ParseTreeVisitor
-      def children
-        Array(@node.variables)
-      end
-    end
  end

  Template.register_tag('cycle', Cycle)
--- a/lib/liquid/tags/for.rb
+++ b/lib/liquid/tags/for.rb
@@ -46,7 +46,8 @@ module Liquid
  class For < Block
    Syntax = /\A(#{VariableSegment}+)\s+in\s+(#{QuotedFragment}+)\s*(reversed)?/o

-    attr_reader :collection_name, :variable_name, :limit, :from
+    attr_reader :collection_name
+    attr_reader :variable_name

    def initialize(tag_name, markup, options)
      super
@@ -119,28 +120,19 @@ module Liquid
    private

    def collection_segment(context)
-      offsets = context.registers[:for] ||= {}
+      offsets = context.registers[:for] ||= Hash.new(0)

      from = if @from == :continue
        offsets[@name].to_i
      else
-        from_value = context.evaluate(@from)
-        if from_value.nil?
-          0
-        else
-          Utils.to_integer(from_value)
-        end
+        context.evaluate(@from).to_i
      end

      collection = context.evaluate(@collection_name)
-      collection = collection.to_a if collection.is_a?(Range)
+      collection = collection.step(1).to_a if collection.is_a?(Range)

-      limit_value = context.evaluate(@limit)
-      to = if limit_value.nil?
-        nil
-      else
-        Utils.to_integer(limit_value) + from
-      end
+      limit = context.evaluate(@limit)
+      to = limit ? limit.to_i + from : nil

      segment = Utils.slice_collection(collection, from, to)
      segment.reverse! if @reversed
@@ -156,19 +148,19 @@ module Liquid

      result = ''

-      context.stack('forloop', @variable_name) do
+      context.stack do
        loop_vars = Liquid::ForloopDrop.new(@name, length, for_stack[-1])

        for_stack.push(loop_vars)

        begin
          context['forloop'.freeze] = loop_vars
-          level = context.create_level(@variable_name)

-          segment.each do |item|
-            context.set_level(@variable_name, item, level)
+          segment.each_with_index do |item, index|
+            context[@variable_name] = item
            result << @for_block.render(context)
            loop_vars.send(:increment!)
+
            # Handle any interrupts if they exist.
            if context.interrupt?
              interrupt = context.pop_interrupt
@@ -176,10 +168,7 @@ module Liquid
              next if interrupt.is_a? ContinueInterrupt
            end
          end
-          context.unset(@variable_name)
-          context.unset('forloop'.freeze)
        ensure
-
          for_stack.pop
        end
      end
@@ -203,12 +192,6 @@ module Liquid
    def render_else(context)
      @else_block ? @else_block.render(context) : ''.freeze
    end
-
-    class ParseTreeVisitor < Liquid::ParseTreeVisitor
-      def children
-        (super + [@node.limit, @node.from, @node.collection_name]).compact
-      end
-    end
  end

  Template.register_tag('for'.freeze, For)
--- a/lib/liquid/tags/if.rb
+++ b/lib/liquid/tags/if.rb
@@ -12,9 +12,7 @@ module Liquid
  class If < Block
    Syntax = /(#{QuotedFragment})\s*([=!<>a-z_]+)?\s*(#{QuotedFragment})?/o
    ExpressionsAndOperators = /(?:\b(?:\s?and\s?|\s?or\s?)\b|(?:\s*(?!\b(?:\s?and\s?|\s?or\s?)\b)(?:#{QuotedFragment}|\S+)\s*)+)/o
-    BOOLEAN_OPERATORS = %w(and or).freeze
-
-    attr_reader :blocks
+    BOOLEAN_OPERATORS = %w(and or)

    def initialize(tag_name, markup, options)
      super
@@ -22,15 +20,15 @@ module Liquid
      push_block('if'.freeze, markup)
    end

-    def nodelist
-      @blocks.map(&:attachment)
-    end
-
    def parse(tokens)
      while parse_body(@blocks.last.attachment, tokens)
      end
    end

+    def nodelist
+      @blocks.map(&:attachment)
+    end
+
    def unknown_tag(tag, markup, tokens)
      if ['elsif'.freeze, 'else'.freeze].include?(tag)
        push_block(tag, markup)
@@ -40,12 +38,14 @@ module Liquid
    end

    def render(context)
-      @blocks.each do |block|
-        if block.evaluate(context)
-          return block.attachment.render(context)
+      context.stack do
+        @blocks.each do |block|
+          if block.evaluate(context)
+            return block.attachment.render(context)
+          end
        end
+        ''.freeze
      end
-      ''.freeze
    end

    private
@@ -108,12 +108,6 @@ module Liquid
        Condition.new(a)
      end
    end
-
-    class ParseTreeVisitor < Liquid::ParseTreeVisitor
-      def children
-        @node.blocks
-      end
-    end
  end

  Template.register_tag('if'.freeze, If)
--- a/lib/liquid/tags/ifchanged.rb
+++ b/lib/liquid/tags/ifchanged.rb
@@ -1,13 +1,15 @@
 module Liquid
  class Ifchanged < Block
    def render(context)
-      output = super
+      context.stack do
+        output = super

-      if output != context.registers[:ifchanged]
-        context.registers[:ifchanged] = output
-        output
-      else
-        ''.freeze
+        if output != context.registers[:ifchanged]
+          context.registers[:ifchanged] = output
+          output
+        else
+          ''.freeze
+        end
      end
    end
  end
--- a/lib/liquid/tags/include.rb
+++ b/lib/liquid/tags/include.rb
@@ -16,8 +16,6 @@ module Liquid
  class Include < Tag
    Syntax = /(#{QuotedFragment}+)(\s+(?:with|for)\s+(#{QuotedFragment}+))?/o

-    attr_reader :template_name_expr, :variable_name_expr, :attributes
-
    def initialize(tag_name, markup, options)
      super

@@ -60,7 +58,7 @@ module Liquid
      begin
        context.template_name = template_name
        context.partial = true
-        context.stack(context_variable_name, *@attributes.keys) do
+        context.stack do
          @attributes.each do |key, value|
            context[key] = context.evaluate(value)
          end
@@ -109,15 +107,6 @@ module Liquid

      file_system.read_template_file(context.evaluate(@template_name_expr))
    end
-
-    class ParseTreeVisitor < Liquid::ParseTreeVisitor
-      def children
-        [
-          @node.template_name_expr,
-          @node.variable_name_expr
-        ] + @node.attributes.values
-      end
-    end
  end

  Template.register_tag('include'.freeze, Include)
--- a/lib/liquid/tags/table_row.rb
+++ b/lib/liquid/tags/table_row.rb
@@ -2,8 +2,6 @@ module Liquid
  class TableRow < Block
    Syntax = /(\w+)\s+in\s+(#{QuotedFragment}+)/o

-    attr_reader :variable_name, :collection_name, :attributes
-
    def initialize(tag_name, markup, options)
      super
      if markup =~ Syntax
@@ -31,11 +29,11 @@ module Liquid
      cols = context.evaluate(@attributes['cols'.freeze]).to_i

      result = "<tr class=\"row1\">\n"
-      context.stack('tablerowloop', @variable_name) do
+      context.stack do
        tablerowloop = Liquid::TablerowloopDrop.new(length, cols)
        context['tablerowloop'.freeze] = tablerowloop

-        collection.each do |item|
+        collection.each_with_index do |item, index|
          context[@variable_name] = item

          result << "<td class=\"col#{tablerowloop.col}\">" << super << '</td>'
@@ -50,12 +48,6 @@ module Liquid
      result << "</tr>\n"
      result
    end
-
-    class ParseTreeVisitor < Liquid::ParseTreeVisitor
-      def children
-        super + @node.attributes.values + [@node.collection_name]
-      end
-    end
  end

  Template.register_tag('tablerow'.freeze, TableRow)
--- a/lib/liquid/tags/unless.rb
+++ b/lib/liquid/tags/unless.rb
@@ -7,20 +7,22 @@ module Liquid
  #
  class Unless < If
    def render(context)
-      # First condition is interpreted backwards ( if not )
-      first_block = @blocks.first
-      unless first_block.evaluate(context)
-        return first_block.attachment.render(context)
-      end
-
-      # After the first condition unless works just like if
-      @blocks[1..-1].each do |block|
-        if block.evaluate(context)
-          return block.attachment.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(context)
        end
-      end

-      ''.freeze
+        # After the first condition unless works just like if
+        @blocks[1..-1].each do |block|
+          if block.evaluate(context)
+            return block.attachment.render(context)
+          end
+        end
+
+        ''.freeze
+      end
    end
  end

--- a/lib/liquid/utils.rb
+++ b/lib/liquid/utils.rb
@@ -46,11 +46,11 @@ module Liquid
    def self.to_number(obj)
      case obj
      when Float
-        BigDecimal(obj.to_s)
+        BigDecimal.new(obj.to_s)
      when Numeric
        obj
      when String
-        (obj.strip =~ /\A-?\d+\.\d+\z/) ? BigDecimal(obj) : obj.to_i
+        (obj.strip =~ /\A-?\d+\.\d+\z/) ? BigDecimal.new(obj) : obj.to_i
      else
        if obj.respond_to?(:to_number)
          obj.to_number
--- a/lib/liquid/variable.rb
+++ b/lib/liquid/variable.rb
@@ -10,16 +10,10 @@ module Liquid
  #   {{ user | link }}
  #
  class Variable
-    FilterMarkupRegex = /#{FilterSeparator}\s*(.*)/om
    FilterParser = /(?:\s+|#{QuotedFragment}|#{ArgumentSeparator})+/o
-    FilterArgsRegex = /(?:#{FilterArgumentSeparator}|#{ArgumentSeparator})\s*((?:\w+\s*\:\s*)?#{QuotedFragment})/o
-    JustTagAttributes = /\A#{TagAttributes}\z/o
-    MarkupWithQuotedFragment = /(#{QuotedFragment})(.*)/om
-
    attr_accessor :filters, :name, :line_number
    attr_reader :parse_context
    alias_method :options, :parse_context
-
    include ParserSwitching

    def initialize(markup, parse_context)
@@ -41,17 +35,17 @@ module Liquid

    def lax_parse(markup)
      @filters = []
-      return unless markup =~ MarkupWithQuotedFragment
+      return unless markup =~ /(#{QuotedFragment})(.*)/om

      name_markup = $1
      filter_markup = $2
      @name = Expression.parse(name_markup)
-      if filter_markup =~ FilterMarkupRegex
+      if filter_markup =~ /#{FilterSeparator}\s*(.*)/om
        filters = $1.scan(FilterParser)
        filters.each do |f|
          next unless f =~ /\w+/
          filtername = Regexp.last_match(0)
-          filterargs = f.scan(FilterArgsRegex).flatten
+          filterargs = f.scan(/(?:#{FilterArgumentSeparator}|#{ArgumentSeparator})\s*((?:\w+\s*\:\s*)?#{QuotedFragment})/o).flatten
          @filters << parse_filter_expressions(filtername, filterargs)
        end
      end
@@ -95,17 +89,16 @@ module Liquid

    def parse_filter_expressions(filter_name, unparsed_args)
      filter_args = []
-      keyword_args = nil
+      keyword_args = {}
      unparsed_args.each do |a|
-        if matches = a.match(JustTagAttributes)
-          keyword_args ||= {}
+        if matches = a.match(/\A#{TagAttributes}\z/o)
          keyword_args[matches[1]] = Expression.parse(matches[2])
        else
          filter_args << Expression.parse(a)
        end
      end
      result = [filter_name, filter_args]
-      result << keyword_args if keyword_args
+      result << keyword_args unless keyword_args.empty?
      result
    end

@@ -139,11 +132,5 @@ module Liquid
        raise error
      end
    end
-
-    class ParseTreeVisitor < Liquid::ParseTreeVisitor
-      def children
-        [@node.name] + @node.filters.flatten
-      end
-    end
  end
 end
--- a/lib/liquid/variable_lookup.rb
+++ b/lib/liquid/variable_lookup.rb
@@ -1,7 +1,7 @@
 module Liquid
  class VariableLookup
    SQUARE_BRACKETED = /\A\[(.*)\]\z/m
-    COMMAND_METHODS = ['size'.freeze, 'first'.freeze, 'last'.freeze].freeze
+    COMMAND_METHODS = ['size'.freeze, 'first'.freeze, 'last'.freeze]

    attr_reader :name, :lookups

@@ -78,11 +78,5 @@ module Liquid
    def state
      [@name, @lookups, @command_flags]
    end
-
-    class ParseTreeVisitor < Liquid::ParseTreeVisitor
-      def children
-        @node.lookups
-      end
-    end
  end
 end
--- a/lib/liquid/version.rb
+++ b/lib/liquid/version.rb
@@ -1,5 +1,4 @@
 # encoding: utf-8
-
 module Liquid
-  VERSION = "4.0.3".freeze
+  VERSION = "4.0.0"
 end
--- a/liquid.gemspec
+++ b/liquid.gemspec
@@ -1,5 +1,4 @@
 # encoding: utf-8
-
 lib = File.expand_path('../lib/', __FILE__)
 $LOAD_PATH.unshift lib unless $LOAD_PATH.include?(lib)

--- a/performance/memory_profile.rb
+++ b/performance/memory_profile.rb
@@ -1,26 +0,0 @@
-# frozen_string_literal: true
-
-require 'benchmark/ips'
-require 'memory_profiler'
-require_relative 'theme_runner'
-
-def profile(phase, &block)
-  puts
-  puts "#{phase}:"
-  puts
-
-  report = MemoryProfiler.report(&block)
-
-  report.pretty_print(
-    color_output: true,
-    scale_bytes: true,
-    detailed_report: true
-  )
-end
-
-Liquid::Template.error_mode = ARGV.first.to_sym if ARGV.first
-
-profiler = ThemeRunner.new
-
-profile("Parsing") { profiler.compile }
-profile("Rendering") { profiler.render }
--- a/performance/shopify/comment_form.rb
+++ b/performance/shopify/comment_form.rb
@@ -15,7 +15,7 @@ class CommentForm < Liquid::Block
  def render(context)
    article = context[@variable_name]

-    context.stack('form') do
+    context.stack do
      context['form'] = {
        'posted_successfully?' => context.registers[:posted_successfully],
        'errors' => context['comment.errors'],
--- a/performance/shopify/paginate.rb
+++ b/performance/shopify/paginate.rb
@@ -24,7 +24,7 @@ class Paginate < Liquid::Block
  def render(context)
    @context = context

-    context.stack('paginate') do
+    context.stack do
      current_page  = context['current_page'].to_i

      pagination = {
--- a/test/integration/block_test.rb
+++ b/test/integration/block_test.rb
@@ -1,12 +0,0 @@
-require 'test_helper'
-
-class BlockTest < Minitest::Test
-  include Liquid
-
-  def test_unexpected_end_tag
-    exc = assert_raises(SyntaxError) do
-      Template.parse("{% if true %}{% endunless %}")
-    end
-    assert_equal exc.message, "Liquid syntax error: 'endunless' is not a valid delimiter for if tags. use endif"
-  end
-end
--- a/test/integration/drop_test.rb
+++ b/test/integration/drop_test.rb
@@ -1,6 +1,14 @@
 require 'test_helper'

 class ContextDrop < Liquid::Drop
+  def scopes
+    @context.scopes.size
+  end
+
+  def scopes_as_array
+    (1..@context.scopes.size).to_a
+  end
+
  def loop_pos
    @context['forloop.index']
  end
@@ -186,6 +194,31 @@ class DropsTest < Minitest::Test
    end
  end

+  def test_scope
+    assert_equal '1', Liquid::Template.parse('{{ context.scopes }}').render!('context' => ContextDrop.new)
+    assert_equal '2', Liquid::Template.parse('{%for i in dummy%}{{ context.scopes }}{%endfor%}').render!('context' => ContextDrop.new, 'dummy' => [1])
+    assert_equal '3', Liquid::Template.parse('{%for i in dummy%}{%for i in dummy%}{{ context.scopes }}{%endfor%}{%endfor%}').render!('context' => ContextDrop.new, 'dummy' => [1])
+  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 '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])
+  end
+
+  def test_scope_with_assigns
+    assert_equal 'variable', Liquid::Template.parse('{% assign a = "variable"%}{{a}}').render!('context' => ContextDrop.new)
+    assert_equal 'variable', Liquid::Template.parse('{% assign a = "variable"%}{%for i in dummy%}{{a}}{%endfor%}').render!('context' => ContextDrop.new, 'dummy' => [1])
+    assert_equal 'test', Liquid::Template.parse('{% assign header_gif = "test"%}{{header_gif}}').render!('context' => ContextDrop.new)
+    assert_equal 'test', Liquid::Template.parse("{% assign header_gif = 'test'%}{{header_gif}}").render!('context' => ContextDrop.new)
+  end
+
+  def test_scope_from_tags
+    assert_equal '1', Liquid::Template.parse('{% for i in context.scopes_as_array %}{{i}}{% endfor %}').render!('context' => ContextDrop.new, 'dummy' => [1])
+    assert_equal '12', Liquid::Template.parse('{%for a in dummy%}{% for i in context.scopes_as_array %}{{i}}{% endfor %}{% endfor %}').render!('context' => ContextDrop.new, 'dummy' => [1])
+    assert_equal '123', Liquid::Template.parse('{%for a in dummy%}{%for a in dummy%}{% for i in context.scopes_as_array %}{{i}}{% endfor %}{% endfor %}{% endfor %}').render!('context' => ContextDrop.new, 'dummy' => [1])
+  end
+
  def test_access_context_from_drop
    assert_equal '123', Liquid::Template.parse('{%for a in dummy%}{{ context.loop_pos }}{% endfor %}').render!('context' => ContextDrop.new, 'dummy' => [1, 2, 3])
  end
--- a/test/integration/error_handling_test.rb
+++ b/test/integration/error_handling_test.rb
@@ -123,7 +123,7 @@ class ErrorHandlingTest < Minitest::Test
            ',
      error_mode: :warn,
      line_numbers: true
-    )
+                                     )

    assert_equal ['Liquid syntax error (line 4): Unexpected character = in "1 =! 2"'],
      template.warnings.map(&:message)
@@ -140,7 +140,7 @@ class ErrorHandlingTest < Minitest::Test
                ',
        error_mode: :strict,
        line_numbers: true
-      )
+                            )
    end

    assert_equal 'Liquid syntax error (line 4): Unexpected character = in "1 =! 2"', err.message
@@ -158,7 +158,7 @@ class ErrorHandlingTest < Minitest::Test
          bla
                ',
        line_numbers: true
-      )
+                            )
    end

    assert_equal "Liquid syntax error (line 5): Unknown tag 'foo'", err.message
--- a/test/integration/parse_tree_visitor_test.rb
+++ b/test/integration/parse_tree_visitor_test.rb
@@ -1,247 +0,0 @@
-# frozen_string_literal: true
-
-require 'test_helper'
-
-class ParseTreeVisitorTest < Minitest::Test
-  include Liquid
-
-  def test_variable
-    assert_equal(
-      ["test"],
-      visit(%({{ test }}))
-    )
-  end
-
-  def test_varible_with_filter
-    assert_equal(
-      ["test", "infilter"],
-      visit(%({{ test | split: infilter }}))
-    )
-  end
-
-  def test_dynamic_variable
-    assert_equal(
-      ["test", "inlookup"],
-      visit(%({{ test[inlookup] }}))
-    )
-  end
-
-  def test_if_condition
-    assert_equal(
-      ["test"],
-      visit(%({% if test %}{% endif %}))
-    )
-  end
-
-  def test_complex_if_condition
-    assert_equal(
-      ["test"],
-      visit(%({% if 1 == 1 and 2 == test %}{% endif %}))
-    )
-  end
-
-  def test_if_body
-    assert_equal(
-      ["test"],
-      visit(%({% if 1 == 1 %}{{ test }}{% endif %}))
-    )
-  end
-
-  def test_unless_condition
-    assert_equal(
-      ["test"],
-      visit(%({% unless test %}{% endunless %}))
-    )
-  end
-
-  def test_complex_unless_condition
-    assert_equal(
-      ["test"],
-      visit(%({% unless 1 == 1 and 2 == test %}{% endunless %}))
-    )
-  end
-
-  def test_unless_body
-    assert_equal(
-      ["test"],
-      visit(%({% unless 1 == 1 %}{{ test }}{% endunless %}))
-    )
-  end
-
-  def test_elsif_condition
-    assert_equal(
-      ["test"],
-      visit(%({% if 1 == 1 %}{% elsif test %}{% endif %}))
-    )
-  end
-
-  def test_complex_elsif_condition
-    assert_equal(
-      ["test"],
-      visit(%({% if 1 == 1 %}{% elsif 1 == 1 and 2 == test %}{% endif %}))
-    )
-  end
-
-  def test_elsif_body
-    assert_equal(
-      ["test"],
-      visit(%({% if 1 == 1 %}{% elsif 2 == 2 %}{{ test }}{% endif %}))
-    )
-  end
-
-  def test_else_body
-    assert_equal(
-      ["test"],
-      visit(%({% if 1 == 1 %}{% else %}{{ test }}{% endif %}))
-    )
-  end
-
-  def test_case_left
-    assert_equal(
-      ["test"],
-      visit(%({% case test %}{% endcase %}))
-    )
-  end
-
-  def test_case_condition
-    assert_equal(
-      ["test"],
-      visit(%({% case 1 %}{% when test %}{% endcase %}))
-    )
-  end
-
-  def test_case_when_body
-    assert_equal(
-      ["test"],
-      visit(%({% case 1 %}{% when 2 %}{{ test }}{% endcase %}))
-    )
-  end
-
-  def test_case_else_body
-    assert_equal(
-      ["test"],
-      visit(%({% case 1 %}{% else %}{{ test }}{% endcase %}))
-    )
-  end
-
-  def test_for_in
-    assert_equal(
-      ["test"],
-      visit(%({% for x in test %}{% endfor %}))
-    )
-  end
-
-  def test_for_limit
-    assert_equal(
-      ["test"],
-      visit(%({% for x in (1..5) limit: test %}{% endfor %}))
-    )
-  end
-
-  def test_for_offset
-    assert_equal(
-      ["test"],
-      visit(%({% for x in (1..5) offset: test %}{% endfor %}))
-    )
-  end
-
-  def test_for_body
-    assert_equal(
-      ["test"],
-      visit(%({% for x in (1..5) %}{{ test }}{% endfor %}))
-    )
-  end
-
-  def test_tablerow_in
-    assert_equal(
-      ["test"],
-      visit(%({% tablerow x in test %}{% endtablerow %}))
-    )
-  end
-
-  def test_tablerow_limit
-    assert_equal(
-      ["test"],
-      visit(%({% tablerow x in (1..5) limit: test %}{% endtablerow %}))
-    )
-  end
-
-  def test_tablerow_offset
-    assert_equal(
-      ["test"],
-      visit(%({% tablerow x in (1..5) offset: test %}{% endtablerow %}))
-    )
-  end
-
-  def test_tablerow_body
-    assert_equal(
-      ["test"],
-      visit(%({% tablerow x in (1..5) %}{{ test }}{% endtablerow %}))
-    )
-  end
-
-  def test_cycle
-    assert_equal(
-      ["test"],
-      visit(%({% cycle test %}))
-    )
-  end
-
-  def test_assign
-    assert_equal(
-      ["test"],
-      visit(%({% assign x = test %}))
-    )
-  end
-
-  def test_capture
-    assert_equal(
-      ["test"],
-      visit(%({% capture x %}{{ test }}{% endcapture %}))
-    )
-  end
-
-  def test_include
-    assert_equal(
-      ["test"],
-      visit(%({% include test %}))
-    )
-  end
-
-  def test_include_with
-    assert_equal(
-      ["test"],
-      visit(%({% include "hai" with test %}))
-    )
-  end
-
-  def test_include_for
-    assert_equal(
-      ["test"],
-      visit(%({% include "hai" for test %}))
-    )
-  end
-
-  def test_preserve_tree_structure
-    assert_equal(
-      [[nil, [
-        [nil, [[nil, [["other", []]]]]],
-        ["test", []],
-        ["xs", []]
-      ]]],
-      traversal(%({% for x in xs offset: test %}{{ other }}{% endfor %})).visit
-    )
-  end
-
-  private
-
-  def traversal(template)
-    ParseTreeVisitor
-      .for(Template.parse(template).root)
-      .add_callback_for(VariableLookup, &:name)
-  end
-
-  def visit(template)
-    traversal(template).visit.flatten.compact
-  end
-end
--- a/test/integration/parsing_quirks_test.rb
+++ b/test/integration/parsing_quirks_test.rb
@@ -99,7 +99,7 @@ class ParsingQuirksTest < Minitest::Test
      # After the messed up quotes a filter without parameters (reverse) should work
      # but one with parameters (remove) shouldn't be detected.
      assert_template_result('here',  "{{ 'hi there' | split:\"t\"\" | reverse | first}}")
-      assert_template_result('hi ', "{{ 'hi there' | split:\"t\"\" | remove:\"i\" | first}}")
+      assert_template_result('hi ',  "{{ 'hi there' | split:\"t\"\" | remove:\"i\" | first}}")
    end
  end

--- a/test/integration/standard_filter_test.rb
+++ b/test/integration/standard_filter_test.rb
@@ -158,10 +158,6 @@ class StandardFiltersTest < Minitest::Test
    assert_equal '1', @filters.url_decode(1)
    assert_equal '2001-02-03', @filters.url_decode(Date.new(2001, 2, 3))
    assert_nil @filters.url_decode(nil)
-    exception = assert_raises Liquid::ArgumentError do
-      @filters.url_decode('%ff')
-    end
-    assert_equal 'Liquid error: invalid byte sequence in UTF-8', exception.message
  end

  def test_truncatewords
@@ -181,9 +177,6 @@ class StandardFiltersTest < Minitest::Test
    assert_equal 'test', @filters.strip_html("<div\nclass='multiline'>test</div>")
    assert_equal 'test', @filters.strip_html("<!-- foo bar \n test -->test")
    assert_equal '', @filters.strip_html(nil)
-
-    # Quirk of the existing implementation
-    assert_equal 'foo;', @filters.strip_html("<<<script </script>script>foo;</script>")
  end

  def test_join
@@ -197,11 +190,6 @@ class StandardFiltersTest < Minitest::Test
    assert_equal [{ "a" => 1 }, { "a" => 2 }, { "a" => 3 }, { "a" => 4 }], @filters.sort([{ "a" => 4 }, { "a" => 3 }, { "a" => 1 }, { "a" => 2 }], "a")
  end

-  def test_sort_with_nils
-    assert_equal [1, 2, 3, 4, nil], @filters.sort([nil, 4, 3, 2, 1])
-    assert_equal [{ "a" => 1 }, { "a" => 2 }, { "a" => 3 }, { "a" => 4 }, {}], @filters.sort([{ "a" => 4 }, { "a" => 3 }, {}, { "a" => 1 }, { "a" => 2 }], "a")
-  end
-
  def test_sort_when_property_is_sometimes_missing_puts_nils_last
    input = [
      { "price" => 4, "handle" => "alpha" },
@@ -220,89 +208,14 @@ class StandardFiltersTest < Minitest::Test
    assert_equal expectation, @filters.sort(input, "price")
  end

-  def test_sort_natural
-    assert_equal ["a", "B", "c", "D"], @filters.sort_natural(["c", "D", "a", "B"])
-    assert_equal [{ "a" => "a" }, { "a" => "B" }, { "a" => "c" }, { "a" => "D" }], @filters.sort_natural([{ "a" => "D" }, { "a" => "c" }, { "a" => "a" }, { "a" => "B" }], "a")
-  end
-
-  def test_sort_natural_with_nils
-    assert_equal ["a", "B", "c", "D", nil], @filters.sort_natural([nil, "c", "D", "a", "B"])
-    assert_equal [{ "a" => "a" }, { "a" => "B" }, { "a" => "c" }, { "a" => "D" }, {}], @filters.sort_natural([{ "a" => "D" }, { "a" => "c" }, {}, { "a" => "a" }, { "a" => "B" }], "a")
-  end
-
-  def test_sort_natural_when_property_is_sometimes_missing_puts_nils_last
-    input = [
-      { "price" => "4", "handle" => "alpha" },
-      { "handle" => "beta" },
-      { "price" => "1", "handle" => "gamma" },
-      { "handle" => "delta" },
-      { "price" => 2, "handle" => "epsilon" }
-    ]
-    expectation = [
-      { "price" => "1", "handle" => "gamma" },
-      { "price" => 2, "handle" => "epsilon" },
-      { "price" => "4", "handle" => "alpha" },
-      { "handle" => "delta" },
-      { "handle" => "beta" }
-    ]
-    assert_equal expectation, @filters.sort_natural(input, "price")
-  end
-
-  def test_sort_natural_case_check
-    input = [
-      { "key" => "X" },
-      { "key" => "Y" },
-      { "key" => "Z" },
-      { "fake" => "t" },
-      { "key" => "a" },
-      { "key" => "b" },
-      { "key" => "c" }
-    ]
-    expectation = [
-      { "key" => "a" },
-      { "key" => "b" },
-      { "key" => "c" },
-      { "key" => "X" },
-      { "key" => "Y" },
-      { "key" => "Z" },
-      { "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"])
-  end
-
  def test_sort_empty_array
    assert_equal [], @filters.sort([], "a")
  end

-  def test_sort_invalid_property
-    foo = [
-      [1],
-      [2],
-      [3]
-    ]
-
-    assert_raises Liquid::ArgumentError do
-      @filters.sort(foo, "bar")
-    end
-  end
-
  def test_sort_natural_empty_array
    assert_equal [], @filters.sort_natural([], "a")
  end

-  def test_sort_natural_invalid_property
-    foo = [
-      [1],
-      [2],
-      [3]
-    ]
-
-    assert_raises Liquid::ArgumentError do
-      @filters.sort_natural(foo, "bar")
-    end
-  end
-
  def test_legacy_sort_hash
    assert_equal [{ a: 1, b: 2 }], @filters.sort({ a: 1, b: 2 })
  end
@@ -326,34 +239,10 @@ class StandardFiltersTest < Minitest::Test
    assert_equal [], @filters.uniq([], "a")
  end

-  def test_uniq_invalid_property
-    foo = [
-      [1],
-      [2],
-      [3]
-    ]
-
-    assert_raises Liquid::ArgumentError do
-      @filters.uniq(foo, "bar")
-    end
-  end
-
  def test_compact_empty_array
    assert_equal [], @filters.compact([], "a")
  end

-  def test_compact_invalid_property
-    foo = [
-      [1],
-      [2],
-      [3]
-    ]
-
-    assert_raises Liquid::ArgumentError do
-      @filters.compact(foo, "bar")
-    end
-  end
-
  def test_reverse
    assert_equal [4, 3, 2, 1], @filters.reverse([1, 2, 3, 4])
  end
@@ -405,11 +294,11 @@ class StandardFiltersTest < Minitest::Test
  def test_map_over_drops_returning_procs
    drops = [
      {
-        "proc" => ->{ "foo" }
+        "proc" => ->{ "foo" },
      },
      {
-        "proc" => ->{ "bar" }
-      }
+        "proc" => ->{ "bar" },
+      },
    ]
    templ = '{{ drops | map: "proc" }}'
    assert_template_result "foobar", templ, "drops" => drops
@@ -419,29 +308,6 @@ class StandardFiltersTest < Minitest::Test
    assert_template_result "123", '{{ foo | map: "foo" }}', "foo" => TestEnumerable.new
  end

-  def test_map_returns_empty_on_2d_input_array
-    foo = [
-      [1],
-      [2],
-      [3]
-    ]
-
-    assert_raises Liquid::ArgumentError do
-      @filters.map(foo, "bar")
-    end
-  end
-
-  def test_map_returns_empty_with_no_property
-    foo = [
-      [1],
-      [2],
-      [3]
-    ]
-    assert_raises Liquid::ArgumentError do
-      @filters.map(foo, nil)
-    end
-  end
-
  def test_sort_works_on_enumerables
    assert_template_result "213", '{{ foo | sort: "bar" | map: "foo" }}', "foo" => TestEnumerable.new
  end
@@ -472,9 +338,9 @@ class StandardFiltersTest < Minitest::Test
    assert_equal '07/05/2006', @filters.date("2006-07-05 10:00:00", "%m/%d/%Y")

    assert_equal "07/16/2004", @filters.date("Fri Jul 16 01:00:00 2004", "%m/%d/%Y")
-    assert_equal Date.today.year.to_s, @filters.date('now', '%Y')
-    assert_equal Date.today.year.to_s, @filters.date('today', '%Y')
-    assert_equal Date.today.year.to_s, @filters.date('Today', '%Y')
+    assert_equal "#{Date.today.year}", @filters.date('now', '%Y')
+    assert_equal "#{Date.today.year}", @filters.date('today', '%Y')
+    assert_equal "#{Date.today.year}", @filters.date('Today', '%Y')

    assert_nil @filters.date(nil, "%B")

@@ -630,28 +496,6 @@ class StandardFiltersTest < Minitest::Test
    assert_template_result "5", "{{ price | floor }}", 'price' => NumberLikeThing.new(5.4)
  end

-  def test_at_most
-    assert_template_result "4", "{{ 5 | at_most:4 }}"
-    assert_template_result "5", "{{ 5 | at_most:5 }}"
-    assert_template_result "5", "{{ 5 | at_most:6 }}"
-
-    assert_template_result "4.5", "{{ 4.5 | at_most:5 }}"
-    assert_template_result "5", "{{ width | at_most:5 }}", 'width' => NumberLikeThing.new(6)
-    assert_template_result "4", "{{ width | at_most:5 }}", 'width' => NumberLikeThing.new(4)
-    assert_template_result "4", "{{ 5 | at_most: width }}", 'width' => NumberLikeThing.new(4)
-  end
-
-  def test_at_least
-    assert_template_result "5", "{{ 5 | at_least:4 }}"
-    assert_template_result "5", "{{ 5 | at_least:5 }}"
-    assert_template_result "6", "{{ 5 | at_least:6 }}"
-
-    assert_template_result "5", "{{ 4.5 | at_least:5 }}"
-    assert_template_result "6", "{{ width | at_least:5 }}", 'width' => NumberLikeThing.new(6)
-    assert_template_result "5", "{{ width | at_least:5 }}", 'width' => NumberLikeThing.new(4)
-    assert_template_result "6", "{{ 5 | at_least: width }}", 'width' => NumberLikeThing.new(6)
-  end
-
  def test_append
    assigns = { 'a' => 'bc', 'b' => 'd' }
    assert_template_result('bcd', "{{ a | append: 'd'}}", assigns)
@@ -692,78 +536,6 @@ class StandardFiltersTest < Minitest::Test
    assert_template_result('abc', "{{ 'abc' | date: '%D' }}")
  end

-  def test_where
-    input = [
-      { "handle" => "alpha", "ok" => true },
-      { "handle" => "beta", "ok" => false },
-      { "handle" => "gamma", "ok" => false },
-      { "handle" => "delta", "ok" => true }
-    ]
-
-    expectation = [
-      { "handle" => "alpha", "ok" => true },
-      { "handle" => "delta", "ok" => true }
-    ]
-
-    assert_equal expectation, @filters.where(input, "ok", true)
-    assert_equal expectation, @filters.where(input, "ok")
-  end
-
-  def test_where_no_key_set
-    input = [
-      { "handle" => "alpha", "ok" => true },
-      { "handle" => "beta" },
-      { "handle" => "gamma" },
-      { "handle" => "delta", "ok" => true }
-    ]
-
-    expectation = [
-      { "handle" => "alpha", "ok" => true },
-      { "handle" => "delta", "ok" => true }
-    ]
-
-    assert_equal expectation, @filters.where(input, "ok", true)
-    assert_equal expectation, @filters.where(input, "ok")
-  end
-
-  def test_where_non_array_map_input
-    assert_equal [{ "a" => "ok" }], @filters.where({ "a" => "ok" }, "a", "ok")
-    assert_equal [], @filters.where({ "a" => "not ok" }, "a", "ok")
-  end
-
-  def test_where_indexable_but_non_map_value
-    assert_raises(Liquid::ArgumentError) { @filters.where(1, "ok", true) }
-    assert_raises(Liquid::ArgumentError) { @filters.where(1, "ok") }
-  end
-
-  def test_where_non_boolean_value
-    input = [
-      { "message" => "Bonjour!", "language" => "French" },
-      { "message" => "Hello!", "language" => "English" },
-      { "message" => "Hallo!", "language" => "German" }
-    ]
-
-    assert_equal [{ "message" => "Bonjour!", "language" => "French" }], @filters.where(input, "language", "French")
-    assert_equal [{ "message" => "Hallo!", "language" => "German" }], @filters.where(input, "language", "German")
-    assert_equal [{ "message" => "Hello!", "language" => "English" }], @filters.where(input, "language", "English")
-  end
-
-  def test_where_array_of_only_unindexable_values
-    assert_nil @filters.where([nil], "ok", true)
-    assert_nil @filters.where([nil], "ok")
-  end
-
-  def test_where_no_target_value
-    input = [
-      { "foo" => false },
-      { "foo" => true },
-      { "foo" => "for sure" },
-      { "bar" => true }
-    ]
-
-    assert_equal [{ "foo" => true }, { "foo" => "for sure" }], @filters.where(input, "foo")
-  end
-
  private

  def with_timezone(tz)
--- a/test/integration/tags/for_tag_test.rb
+++ b/test/integration/tags/for_tag_test.rb
@@ -48,6 +48,10 @@ HERE

  def test_for_with_variable_range
    assert_template_result(' 1  2  3 ', '{%for item in (1..foobar) %} {{item}} {%endfor%}', "foobar" => 3)
+    assert_template_result(' 1.0  2.0  3.0 ', '{%for item in foobar %} {{item}} {%endfor%}', "foobar" => (1..3.0))
+    assert_template_result(' 1.0  2.0  3.0 ', '{%for item in foobar %} {{item}} {%endfor%}', "foobar" => (1.0..3))
+    assert_template_result(' 1.0  2.0  3.0 ', '{%for item in foobar %} {{item}} {%endfor%}', "foobar" => (1.0..3.0))
+    assert_template_result(' 1.5  2.5 ', '{%for item in foobar %} {{item}} {%endfor%}', "foobar" => (1.5..3))
  end

  def test_for_with_hash_value_range
@@ -103,34 +107,6 @@ HERE
    assert_template_result('3456', '{%for i in array limit: 4 offset: 2 %}{{ i }}{%endfor%}', assigns)
  end

-  def test_limiting_with_invalid_limit
-    assigns = { 'array' => [1, 2, 3, 4, 5, 6, 7, 8, 9, 0] }
-    template = <<-MKUP
-      {% for i in array limit: true offset: 1 %}
-        {{ i }}
-      {% endfor %}
-    MKUP
-
-    exception = assert_raises(Liquid::ArgumentError) do
-      Template.parse(template).render!(assigns)
-    end
-    assert_equal("Liquid error: invalid integer", exception.message)
-  end
-
-  def test_limiting_with_invalid_offset
-    assigns = { 'array' => [1, 2, 3, 4, 5, 6, 7, 8, 9, 0] }
-    template = <<-MKUP
-      {% for i in array limit: 1 offset: true %}
-        {{ i }}
-      {% endfor %}
-    MKUP
-
-    exception = assert_raises(Liquid::ArgumentError) do
-      Template.parse(template).render!(assigns)
-    end
-    assert_equal("Liquid error: invalid integer", exception.message)
-  end
-
  def test_dynamic_variable_limiting
    assigns = { 'array' => [1, 2, 3, 4, 5, 6, 7, 8, 9, 0] }
    assigns['limit'] = 2
@@ -187,7 +163,7 @@ HERE
    assert_template_result(expected, markup, assigns)
  end

-  def test_pause_resume_big_limit
+  def test_pause_resume_BIG_limit
    assigns = { 'array' => { 'items' => [1, 2, 3, 4, 5, 6, 7, 8, 9, 0] } }
    markup = <<-MKUP
      {%for i in array.items limit:3 %}{{i}}{%endfor%}
@@ -206,7 +182,7 @@ HERE
    assert_template_result(expected, markup, assigns)
  end

-  def test_pause_resume_big_offset
+  def test_pause_resume_BIG_offset
    assigns = { 'array' => { 'items' => [1, 2, 3, 4, 5, 6, 7, 8, 9, 0] } }
    markup = '{%for i in array.items limit:3 %}{{i}}{%endfor%}
      next
@@ -368,23 +344,6 @@ HERE
    assert_template_result(expected, template, assigns)
  end

-  def test_overwriting_internal_variable
-    template = <<-HEREDOC
-    {% assign forloop = 'first' %}
-
-    {% for item in items %}
-      {{ forloop }}
-      {% assign forloop = 'second' %}
-      {{ forloop }}
-    {% endfor %}
-
-    {{ forloop }}
-    HEREDOC
-
-    result = Liquid::Template.parse(template).render('items' => '1')
-    assert_equal 'Liquid::ForloopDrop Liquid::ForloopDrop second', result.split.map(&:strip).join(' ')
-  end
-
  class LoaderDrop < Liquid::Drop
    attr_accessor :each_called, :load_slice_called

--- a/test/integration/tags/if_else_tag_test.rb
+++ b/test/integration/tags/if_else_tag_test.rb
@@ -176,7 +176,7 @@ class IfElseTagTest < Minitest::Test
      [false, true, true] => true,
      [false, true, false] => false,
      [false, false, true] => false,
-      [false, false, false] => false
+      [false, false, false] => false,
    }

    tests.each do |vals, expected|
--- a/test/integration/tags/include_tag_test.rb
+++ b/test/integration/tags/include_tag_test.rb
@@ -30,9 +30,6 @@ class TestFileSystem
    when 'assignments'
      "{% assign foo = 'bar' %}"

-    when 'break'
-      "{% break %}"
-
    else
      template_path
    end
@@ -245,9 +242,4 @@ class IncludeTagTest < Minitest::Test

    assert_equal [], template.errors
  end
-
-  def test_break_through_include
-    assert_template_result "1", "{% for i in (1..3) %}{{ i }}{% break %}{{ i }}{% endfor %}"
-    assert_template_result "1", "{% for i in (1..3) %}{{ i }}{% include 'break' %}{{ i }}{% endfor %}"
-  end
 end # IncludeTagTest
--- a/test/integration/template_test.rb
+++ b/test/integration/template_test.rb
@@ -139,16 +139,6 @@ class TemplateTest < Minitest::Test
    refute_nil t.resource_limits.assign_score
  end

-  def test_resource_limits_assign_score_counts_bytes_not_characters
-    t = Template.parse("{% assign foo = 'すごい' %}")
-    t.render
-    assert_equal 9, t.resource_limits.assign_score
-
-    t = Template.parse("{% capture foo %}すごい{% endcapture %}")
-    t.render
-    assert_equal 9, t.resource_limits.assign_score
-  end
-
  def test_resource_limits_assign_score_nested
    t = Template.parse("{% assign foo = 'aaaa' | reverse %}")

@@ -197,14 +187,6 @@ class TemplateTest < Minitest::Test
    assert_equal "ababab", t.render
  end

-  def test_render_length_uses_number_of_bytes_not_characters
-    t = Template.parse("{% if true %}すごい{% endif %}")
-    t.resource_limits.render_length_limit = 10
-    assert_equal "Liquid error: Memory limits exceeded", t.render
-    t.resource_limits.render_length_limit = 18
-    assert_equal "すごい", t.render
-  end
-
  def test_default_resource_limits_unaffected_by_render_with_context
    context = Context.new
    t = Template.parse("{% for a in (1..100) %} {% assign foo = 1 %} {% endfor %}")
@@ -279,15 +261,6 @@ class TemplateTest < Minitest::Test
    assert_equal 'Liquid error: undefined variable d', t.errors[2].message
  end

-  def test_nil_value_does_not_raise
-    Liquid::Template.error_mode = :strict
-    t = Template.parse("some{{x}}thing")
-    result = t.render!({ 'x' => nil }, strict_variables: true)
-
-    assert_equal 0, t.errors.count
-    assert_equal 'something', result
-  end
-
  def test_undefined_variables_raise
    t = Template.parse("{{x}} {{y}} {{z.a}} {{z.b}} {{z.c.d}}")

--- a/test/integration/trim_mode_test.rb
+++ b/test/integration/trim_mode_test.rb
@@ -496,10 +496,6 @@ class TrimModeTest < Minitest::Test
    assert_template_result(expected, text)
  end

-  def test_right_trim_followed_by_tag
-    assert_template_result('ab c', '{{ "a" -}}{{ "b" }} c')
-  end
-
  def test_raw_output
    whitespace = '        '
    text = <<-END_TEMPLATE
--- a/test/integration/variable_test.rb
+++ b/test/integration/variable_test.rb
@@ -89,8 +89,4 @@ class VariableTest < Minitest::Test
  def test_multiline_variable
    assert_equal 'worked', Template.parse("{{\ntest\n}}").render!('test' => 'worked')
  end
-
-  def test_render_symbol
-    assert_template_result 'bar', '{{ foo }}', 'foo' => :bar
-  end
 end
--- a/test/test_helper.rb
+++ b/test/test_helper.rb
--- a/test/unit/condition_unit_test.rb
+++ b/test/unit/condition_unit_test.rb
@@ -24,9 +24,9 @@ class ConditionUnitTest < Minitest::Test
    assert_evaluates_true 1, '<=', 1
    # negative numbers
    assert_evaluates_true 1, '>', -1
-    assert_evaluates_true -1, '<', 1
+    assert_evaluates_true (-1), '<', 1
    assert_evaluates_true 1.0, '>', -1.0
-    assert_evaluates_true -1.0, '<', 1.0
+    assert_evaluates_true (-1.0), '<', 1.0
  end

  def test_default_operators_evalute_false
--- a/test/unit/context_unit_test.rb
+++ b/test/unit/context_unit_test.rb
@@ -102,6 +102,21 @@ class ContextUnitTest < Minitest::Test
    assert_nil @context['does_not_exist']
  end

+  def test_scoping
+    @context.push
+    @context.pop
+
+    assert_raises(Liquid::ContextError) do
+      @context.pop
+    end
+
+    assert_raises(Liquid::ContextError) do
+      @context.push
+      @context.pop
+      @context.pop
+    end
+  end
+
  def test_length_query
    @context['numbers'] = [1, 2, 3, 4]

@@ -155,12 +170,18 @@ class ContextUnitTest < Minitest::Test

  def test_add_item_in_outer_scope
    @context['test'] = 'test'
-
-    @context.stack('test') do
-      assert_equal 'test', @context['test']
-    end
-
+    @context.push
    assert_equal 'test', @context['test']
+    @context.pop
+    assert_equal 'test', @context['test']
+  end
+
+  def test_add_item_in_inner_scope
+    @context.push
+    @context['test'] = 'test'
+    assert_equal 'test', @context['test']
+    @context.pop
+    assert_nil @context['test']
  end

  def test_hierachical_data