Fix leaking error when comparison leads to TypeError

2026-01-02 00:05:42 +03:00 · 2017-01-16 12:26:19 -05:00
54 changed files with 284 additions and 1359 deletions
--- a/.github/probots.yml
+++ b/.github/probots.yml
@@ -1,2 +0,0 @@
-enabled:
-  - cla
--- a/.rubocop.yml
+++ b/.rubocop.yml
@@ -7,6 +7,8 @@ AllCops:

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

 Metrics/ModuleLength:
  Enabled: false
@@ -30,7 +32,7 @@ Lint/UnusedBlockArgument:
  Enabled: false

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

 Lint/UnusedMethodArgument:
  Enabled: false
@@ -59,10 +61,10 @@ Style/BracesAroundHashParameters:
 Style/NumericLiterals:
  Enabled: false

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

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

 Style/Documentation:
@@ -71,19 +73,19 @@ Style/Documentation:
 Style/ClassAndModuleChildren:
  Enabled: false

-Style/TrailingCommaInLiteral:
+Style/TrailingComma:
  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:
@@ -92,7 +94,7 @@ Style/IfUnlessModifier:
 Style/RaiseArgs:
  Enabled: false

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

 Style/RegexpLiteral:
@@ -107,7 +109,7 @@ Performance/Count:
 Style/ConstantName:
  Enabled: false

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

 Style/ClassVars:
@@ -121,7 +123,3 @@ Style/TrivialAccessors:

 Style/WordArray:
  Enabled: false
-
-Style/MethodName:
-  Exclude:
-    - 'example/server/liquid_servlet.rb'
--- a/.rubocop_todo.yml
+++ b/.rubocop_todo.yml
@@ -1,194 +1,72 @@
-# This configuration was generated by
-# `rubocop --auto-gen-config`
-# on 2019-02-03 21:12:39 +0530 using RuboCop version 0.49.1.
+# 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: 5
-# Cop supports --auto-correct.
-# Configuration parameters: EnforcedStyle, SupportedStyles.
-# 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.
-# 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.
-# SupportedStyles: runtime_error, standard_error
-Lint/InheritException:
-  Exclude:
-    - 'lib/liquid/interrupts.rb'
-
-# Offense count: 51
+# Offense count: 53
 Metrics/AbcSize:
-  Max: 56
+  Max: 58

-# Offense count: 11
+# Offense count: 12
 Metrics/CyclomaticComplexity:
-  Max: 12
+  Max: 15

-# Offense count: 639
-# Configuration parameters: AllowHeredoc, AllowURI, URISchemes, IgnoreCopDirectives, IgnoredPatterns.
-# URISchemes: http, https
+# Offense count: 553
+# Configuration parameters: AllowURI, URISchemes.
 Metrics/LineLength:
  Max: 294

-# Offense count: 108
+# Offense count: 77
 # Configuration parameters: CountComments.
 Metrics/MethodLength:
-  Max: 37
+  Max: 46

-# Offense count: 7
+# Offense count: 6
 Metrics/PerceivedComplexity:
-  Max: 11
+  Max: 13

-# Offense count: 10
-# Cop supports --auto-correct.
-# Configuration parameters: EnforcedStyle, SupportedStyles.
-# 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: 1
+Style/AccessorMethodName:
+  Enabled: false

 # Offense count: 1
 # Cop supports --auto-correct.
-# Configuration parameters: EnforcedStyle, SupportedStyles, SingleLineConditionsOnly, IncludeTernaryExpressions.
-# SupportedStyles: assign_to_condition, assign_inside_condition
-Style/ConditionalAssignment:
-  Exclude:
-    - 'lib/liquid/errors.rb'
+Style/ClosingParenthesisIndentation:
+  Enabled: false

-# 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.
-# SupportedStyles: compact, expanded
-Style/EmptyMethod:
-  Exclude:
-    - 'lib/liquid/tag.rb'
-    - 'lib/liquid/tags/comment.rb'
-    - 'lib/liquid/tags/include.rb'
-    - 'test/integration/tags/include_tag_test.rb'
-    - 'test/unit/context_unit_test.rb'
-
-# Offense count: 2
-# Configuration parameters: SupportedStyles.
-# SupportedStyles: annotated, template
-Style/FormatStringToken:
-  EnforcedStyle: template
-
-# Offense count: 14
+# Offense count: 3
 # 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.
-# 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.
-# 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.
-# SupportedStyles: percent, brackets
-Style/SymbolArray:
-  EnforcedStyle: brackets
-
-# Offense count: 2
-# Cop supports --auto-correct.
-# Configuration parameters: EnforcedStyle, SupportedStyles, 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'
+  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
@@ -19,14 +17,9 @@ 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/16
+++ b/16
@@ -1,20 +1,14 @@
 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'
-end
+gem 'stackprof', platforms: :mri_21

 group :test do
-  gem 'rubocop', '~> 0.49.0'
+  gem 'spy', '0.4.1'
+  gem 'benchmark-ips'
+  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
@@ -73,13 +20,10 @@
 * Add concat filter to concatenate arrays (#429) [Diogo Beato]
 * Ruby 1.9 support dropped (#491) [Justin Li]
 * Liquid::Template.file_system's read_template_file method is no longer passed the context. (#441) [James Reid-Smith]
-* Remove `liquid_methods` (See https://github.com/Shopify/liquid/pull/568 for replacement)
+* Remove support for `liquid_methods`
 * Liquid::Template.register_filter raises when the module overrides registered public methods as private or protected (#705) [Gaurav Chande]

 ### Fixed
-
-* Fix variable names being detected as an operator when starting with contains (#788) [Michael Angell]
-* Fix include tag used with strict_variables (#828) [QuickPay]
 * Fix map filter when value is a Proc (#672) [Guillaume Malette]
 * Fix truncate filter when value is not a string (#672) [Guillaume Malette]
 * Fix behaviour of escape filter when input is nil (#665) [Tanel Jakobsoo]
--- 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/2
+++ b/2
@@ -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|
--- 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
@@ -1,7 +1,5 @@
 module Liquid
  class Block < Tag
-    MAX_DEPTH = 100
-
    def initialize(tag_name, markup, options)
      super
      @blank = true
@@ -26,12 +24,12 @@ 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
@@ -50,25 +48,17 @@ module Liquid
    protected

    def parse_body(body, tokens)
-      if parse_context.depth >= MAX_DEPTH
-        raise StackLevelError, "Nesting too deep".freeze
-      end
-      parse_context.depth += 1
-      begin
-        body.parse(tokens, parse_context) do |end_tag_name, end_tag_params|
-          @blank &&= body.blank?
+      body.parse(tokens, parse_context) do |end_tag_name, end_tag_params|
+        @blank &&= body.blank?

-          return false if end_tag_name == block_delimiter
-          unless end_tag_name
-            raise SyntaxError.new(parse_context.locale.t("errors.syntax.tag_never_closed".freeze, block_name: block_name))
-          end
-
-          # this tag is not registered with the system
-          # pass it to the current block for special handling or error reporting
-          unknown_tag(end_tag_name, end_tag_params, tokens)
+        return false if end_tag_name == block_delimiter
+        unless end_tag_name
+          raise SyntaxError.new(parse_context.locale.t("errors.syntax.tag_never_closed".freeze, block_name: block_name))
        end
-      ensure
-        parse_context.depth -= 1
+
+        # this tag is not registered with the system
+        # pass it to the current block for special handling or error reporting
+        unknown_tag(end_tag_name, end_tag_params, tokens)
      end

      true
--- 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 +72,32 @@ 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, token.raw)
+          output << nil
+        rescue ::StandardError => e
+          output << context.handle_error(e, token.line_number, token.raw)
        end
-        idx += 1
      end

      output.join
@@ -99,25 +105,15 @@ 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.respond_to?(:render) ? node.render(context) : node)
      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.length
-      return unless context.resource_limits.reached?
-      raise MemoryError.new("Memory limits exceeded".freeze)
+      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)
@@ -41,22 +41,16 @@ module Liquid
    end

    def evaluate(context = Context.new)
-      condition = self
-      result = nil
-      loop do
-        result = interpret_condition(condition.left, condition.right, condition.operator, context)
+      result = interpret_condition(left, right, operator, context)

-        case condition.child_relation
-        when :or
-          break if result
-        when :and
-          break unless result
-        else
-          break
-        end
-        condition = condition.child_condition
+      case @child_relation
+      when :or
+        result || @child_condition.evaluate(context)
+      when :and
+        result && @child_condition.evaluate(context)
+      else
+        result
      end
-      result
    end

    def or(condition)
@@ -81,10 +75,6 @@ module Liquid
      "#<Condition #{[@left, @operator, @right].compact.join(' '.freeze)}>"
    end

-    protected
-
-    attr_reader :child_relation
-
    private

    def equal_variables(left, right)
@@ -120,23 +110,14 @@ module Liquid

      if operation.respond_to?(:call)
        operation.call(self, left, right)
-      elsif left.respond_to?(operation) && right.respond_to?(operation) && !left.is_a?(Hash) && !right.is_a?(Hash)
+      elsif left.respond_to?(operation) && right.respond_to?(operation)
        begin
          left.send(operation, right)
-        rescue ::ArgumentError => e
+        rescue ::ArgumentError, TypeError => e
          raise Liquid::ArgumentError.new(e.message)
        end
      end
    end
-
-    class ParseTreeVisitor < Liquid::ParseTreeVisitor
-      def children
-        [
-          @node.left, @node.right,
-          @node.child_condition, @node.attachment
-        ].compact
-      end
-    end
  end

  class ElseCondition < Condition
--- a/lib/liquid/context.rb
+++ b/lib/liquid/context.rb
@@ -74,7 +74,7 @@ module Liquid
      @interrupts.pop
    end

-    def handle_error(e, line_number = nil)
+    def handle_error(e, line_number = nil, raw_token = nil)
      e = internal_error unless e.is_a?(Liquid::Error)
      e.template_name ||= template_name
      e.line_number ||= line_number
@@ -89,7 +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)
-      raise StackLevelError, "Nesting too deep".freeze if @scopes.length > Block::MAX_DEPTH
+      raise StackLevelError, "Nesting too deep".freeze if @scopes.length > 100
    end

    # Merge a hash of variables in the current local scope
@@ -160,7 +160,7 @@ module Liquid
    end

    # Fetches an object starting at the local scope and then moving up the hierachy
-    def find_variable(key, raise_on_not_found: true)
+    def find_variable(key)
      # 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) }
@@ -170,10 +170,8 @@ module Liquid

      if scope.nil?
        @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
+          variable = lookup_and_evaluate(e, key)
+          unless variable.nil?
            scope = e
            break
          end
@@ -181,7 +179,7 @@ module Liquid
      end

      scope ||= @environments.last || @scopes.last
-      variable ||= lookup_and_evaluate(scope, key, raise_on_not_found: raise_on_not_found)
+      variable ||= lookup_and_evaluate(scope, key)

      variable = variable.to_liquid
      variable.context = self if variable.respond_to?(:context=)
@@ -189,8 +187,8 @@ module Liquid
      variable
    end

-    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)
+    def lookup_and_evaluate(obj, key)
+      if @strict_variables && obj.respond_to?(:key?) && !obj.key?(key)
        raise Liquid::UndefinedVariable, "undefined variable #{key}"
      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
@@ -12,25 +12,23 @@ 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*/
+    COMPARISON_OPERATOR = /==|!=|<>|<=?|>=?|contains/

    def initialize(input)
-      @ss = StringScanner.new(input)
+      @ss = StringScanner.new(input.rstrip)
    end

    def tokenize
      @output = []

      until @ss.eos?
-        @ss.skip(WHITESPACE_OR_NOTHING)
-        break if @ss.eos?
+        @ss.skip(/\s*/)
        tok = case
        when t = @ss.scan(COMPARISON_OPERATOR) then [:comparison, t]
        when t = @ss.scan(SINGLE_STRING_LITERAL) then [:string, 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_context.rb
+++ b/lib/liquid/parse_context.rb
@@ -1,13 +1,12 @@
 module Liquid
  class ParseContext
-    attr_accessor :locale, :line_number, :trim_whitespace, :depth
+    attr_accessor :locale, :line_number, :trim_whitespace
    attr_reader :partial, :warnings, :error_mode

    def initialize(options = {})
      @template_options = options ? options.dup : {}
      @locale = @template_options[:locale] ||= I18n.new
      @warnings = []
-      self.depth = 0
      self.partial = false
    end

--- 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)
@@ -39,7 +33,7 @@ module Liquid
    end

    def escape(input)
-      CGI.escapeHTML(input.to_s).untaint unless input.nil?
+      CGI.escapeHTML(input).untaint unless input.nil?
    end
    alias_method :h, :escape

@@ -48,16 +42,11 @@ module Liquid
    end

    def url_encode(input)
-      CGI.escape(input.to_s) unless input.nil?
+      CGI.escape(input) unless input.nil?
    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) 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

@@ -470,7 +384,7 @@ module Liquid
      end

      def join(glue)
-        to_a.join(glue.to_s)
+        to_a.join(glue)
      end

      def concat(args)
--- a/lib/liquid/strainer.rb
+++ b/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 self.include?(filter)
+      unless self.class.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(', ')}"
--- 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
@@ -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/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 = []
@@ -82,12 +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
@@ -32,11 +30,11 @@ module Liquid
    end

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

      context.stack do
        key = context.evaluate(@name)
-        iteration = context.registers[:cycle][key].to_i
+        iteration = context.registers[:cycle][key]
        result = context.evaluate(@variables[iteration])
        iteration += 1
        iteration  = 0 if iteration >= @variables.size
@@ -53,12 +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
@@ -23,7 +23,7 @@ module Liquid
  #      {{ item.name }}
  #    {% end %}
  #
-  #  To reverse the for loop simply use {% for item in collection reversed %} (note that the flag's spelling is different to the filter `reverse`)
+  #  To reverse the for loop simply use {% for item in collection reversed %}
  #
  # == Available variables:
  #
@@ -46,8 +46,6 @@ module Liquid
  class For < Block
    Syntax = /\A(#{VariableSegment}+)\s+in\s+(#{QuotedFragment}+)\s*(reversed)?/o

-    attr_reader :collection_name, :variable_name, :limit, :from
-
    def initialize(tag_name, markup, options)
      super
      @from = @limit = nil
@@ -119,7 +117,7 @@ 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
@@ -155,7 +153,7 @@ module Liquid
        begin
          context['forloop'.freeze] = loop_vars

-          segment.each do |item|
+          segment.each_with_index do |item, index|
            context[@variable_name] = item
            result << @for_block.render(context)
            loop_vars.send(:increment!)
@@ -191,12 +189,6 @@ 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)
@@ -85,20 +83,17 @@ module Liquid

    def strict_parse(markup)
      p = Parser.new(markup)
-      condition = parse_binary_comparisons(p)
+      condition = parse_binary_comparison(p)
      p.consume(:end_of_string)
      condition
    end

-    def parse_binary_comparisons(p)
+    def parse_binary_comparison(p)
      condition = parse_comparison(p)
-      first_condition = condition
-      while op = (p.id?('and'.freeze) || p.id?('or'.freeze))
-        child_condition = parse_comparison(p)
-        condition.send(op, child_condition)
-        condition = child_condition
+      if op = (p.id?('and'.freeze) || p.id?('or'.freeze))
+        condition.send(op, parse_binary_comparison(p))
      end
-      first_condition
+      condition
    end

    def parse_comparison(p)
@@ -110,12 +105,6 @@ 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/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

@@ -52,7 +50,7 @@ module Liquid
      variable = if @variable_name_expr
        context.evaluate(@variable_name_expr)
      else
-        context.find_variable(template_name, raise_on_not_found: false)
+        context.find_variable(template_name)
      end

      old_template_name = context.template_name
@@ -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
@@ -35,7 +33,7 @@ module Liquid
        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/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
@@ -97,7 +91,7 @@ module Liquid
      filter_args = []
      keyword_args = {}
      unparsed_args.each do |a|
-        if matches = a.match(JustTagAttributes)
+        if matches = a.match(/\A#{TagAttributes}\z/o)
          keyword_args[matches[1]] = Expression.parse(matches[2])
        else
          filter_args << Expression.parse(a)
@@ -138,11 +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/benchmark.rb
+++ b/performance/benchmark.rb
@@ -5,7 +5,7 @@ Liquid::Template.error_mode = ARGV.first.to_sym if ARGV.first
 profiler = ThemeRunner.new

 Benchmark.ips do |x|
-  x.time = 10
+  x.time = 60
  x.warmup = 5

  puts
@@ -13,6 +13,5 @@ Benchmark.ips do |x|
  puts

  x.report("parse:") { profiler.compile }
-  x.report("render:") { profiler.render }
-  x.report("parse & render:") { profiler.run }
+  x.report("parse & run:") { profiler.run }
 end
--- a/performance/theme_runner.rb
+++ b/performance/theme_runner.rb
@@ -21,100 +21,53 @@ class ThemeRunner
    end
  end

-  # Initialize a new liquid ThemeRunner instance
-  # Will load all templates into memory, do this now so that we don't profile IO.
+  # Load all templates into memory, do this now so that
+  # we don't profile IO.
  def initialize
    @tests = Dir[__dir__ + '/tests/**/*.liquid'].collect do |test|
      next if File.basename(test) == 'theme.liquid'

      theme_path = File.dirname(test) + '/theme.liquid'
-      {
-        liquid: File.read(test),
-        layout: (File.file?(theme_path) ? File.read(theme_path) : nil),
-        template_name: test
-      }
-    end.compact

-    compile_all_tests
+      [File.read(test), (File.file?(theme_path) ? File.read(theme_path) : nil), test]
+    end.compact
  end

-  # `compile` will test just the compilation portion of liquid without any templates
  def compile
-    @tests.each do |test_hash|
-      Liquid::Template.new.parse(test_hash[:liquid])
-      Liquid::Template.new.parse(test_hash[:layout])
+    # Dup assigns because will make some changes to them
+
+    @tests.each do |liquid, layout, template_name|
+      tmpl = Liquid::Template.new
+      tmpl.parse(liquid)
+      tmpl = Liquid::Template.new
+      tmpl.parse(layout)
    end
  end

-  # `run` is called to benchmark rendering and compiling at the same time
  def run
-    each_test do |liquid, layout, assigns, page_template, template_name|
+    # Dup assigns because will make some changes to them
+    assigns = Database.tables.dup
+
+    @tests.each do |liquid, layout, template_name|
+      # Compute page_tempalte outside of profiler run, uninteresting to profiler
+      page_template = File.basename(template_name, File.extname(template_name))
      compile_and_render(liquid, layout, assigns, page_template, template_name)
    end
  end

-  # `render` is called to benchmark just the render portion of liquid
-  def render
-    @compiled_tests.each do |test|
-      tmpl = test[:tmpl]
-      assigns = test[:assigns]
-      layout = test[:layout]
-
-      if layout
-        assigns['content_for_layout'] = tmpl.render!(assigns)
-        layout.render!(assigns)
-      else
-        tmpl.render!(assigns)
-      end
-    end
-  end
-
-  private
-
  def compile_and_render(template, layout, assigns, page_template, template_file)
-    compiled_test = compile_test(template, layout, assigns, page_template, template_file)
-    assigns['content_for_layout'] = compiled_test[:tmpl].render!(assigns)
-    compiled_test[:layout].render!(assigns) if layout
-  end
-
-  def compile_all_tests
-    @compiled_tests = []
-    each_test do |liquid, layout, assigns, page_template, template_name|
-      @compiled_tests << compile_test(liquid, layout, assigns, page_template, template_name)
-    end
-    @compiled_tests
-  end
-
-  def compile_test(template, layout, assigns, page_template, template_file)
-    tmpl = init_template(page_template, template_file)
-    parsed_template = tmpl.parse(template).dup
-
-    if layout
-      parsed_layout = tmpl.parse(layout)
-      { tmpl: parsed_template, assigns: assigns, layout: parsed_layout }
-    else
-      { tmpl: parsed_template, assigns: assigns }
-    end
-  end
-
-  # utility method with similar functionality needed in `compile_all_tests` and `run`
-  def each_test
-    # Dup assigns because will make some changes to them
-    assigns = Database.tables.dup
-
-    @tests.each do |test_hash|
-      # Compute page_template outside of profiler run, uninteresting to profiler
-      page_template = File.basename(test_hash[:template_name], File.extname(test_hash[:template_name]))
-      yield(test_hash[:liquid], test_hash[:layout], assigns, page_template, test_hash[:template_name])
-    end
-  end
-
-  # set up a new Liquid::Template object for use in `compile_and_render` and `compile_test`
-  def init_template(page_template, template_file)
    tmpl = Liquid::Template.new
    tmpl.assigns['page_title'] = 'Page title'
    tmpl.assigns['template'] = page_template
    tmpl.registers[:file_system] = ThemeRunner::FileSystem.new(File.dirname(template_file))
-    tmpl
+
+    content_for_layout = tmpl.parse(template).render!(assigns)
+
+    if layout
+      assigns['content_for_layout'] = content_for_layout
+      tmpl.parse(layout).render!(assigns)
+    else
+      content_for_layout
+    end
  end
 end
--- 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/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

@@ -115,8 +115,4 @@ class ParsingQuirksTest < Minitest::Test
      assert_template_result('12345', "{% for i in (1...5) %}{{ i }}{% endfor %}")
    end
  end
-
-  def test_contains_in_id
-    assert_template_result(' YES ', '{% if containsallshipments == true %} YES {% endif %}', 'containsallshipments' => true)
-  end
 end # ParsingQuirksTest
--- a/test/integration/security_test.rb
+++ b/test/integration/security_test.rb
@@ -63,18 +63,4 @@ class SecurityTest < Minitest::Test

    assert_equal [], (Symbol.all_symbols - current_symbols)
  end
-
-  def test_max_depth_nested_blocks_does_not_raise_exception
-    depth = Liquid::Block::MAX_DEPTH
-    code = "{% if true %}" * depth + "rendered" + "{% endif %}" * depth
-    assert_equal "rendered", Template.parse(code).render!
-  end
-
-  def test_more_than_max_depth_nested_blocks_raises_exception
-    depth = Liquid::Block::MAX_DEPTH + 1
-    code = "{% if true %}" * depth + "rendered" + "{% endif %}" * depth
-    assert_raises(Liquid::StackLevelError) do
-      Template.parse(code).render!
-    end
-  end
 end # SecurityTest
--- a/test/integration/standard_filter_test.rb
+++ b/test/integration/standard_filter_test.rb
@@ -128,16 +128,8 @@ class StandardFiltersTest < Minitest::Test

  def test_escape
    assert_equal '&lt;strong&gt;', @filters.escape('<strong>')
-    assert_equal '1', @filters.escape(1)
-    assert_equal '2001-02-03', @filters.escape(Date.new(2001, 2, 3))
-    assert_nil @filters.escape(nil)
-  end
-
-  def test_h
+    assert_equal nil, @filters.escape(nil)
    assert_equal '&lt;strong&gt;', @filters.h('<strong>')
-    assert_equal '1', @filters.h(1)
-    assert_equal '2001-02-03', @filters.h(Date.new(2001, 2, 3))
-    assert_nil @filters.h(nil)
  end

  def test_escape_once
@@ -146,22 +138,14 @@ class StandardFiltersTest < Minitest::Test

  def test_url_encode
    assert_equal 'foo%2B1%40example.com', @filters.url_encode('foo+1@example.com')
-    assert_equal '1', @filters.url_encode(1)
-    assert_equal '2001-02-03', @filters.url_encode(Date.new(2001, 2, 3))
-    assert_nil @filters.url_encode(nil)
+    assert_equal nil, @filters.url_encode(nil)
  end

  def test_url_decode
    assert_equal 'foo bar', @filters.url_decode('foo+bar')
    assert_equal 'foo bar', @filters.url_decode('foo%20bar')
    assert_equal 'foo+1@example.com', @filters.url_decode('foo%2B1%40example.com')
-    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
+    assert_equal nil, @filters.url_decode(nil)
  end

  def test_truncatewords
@@ -181,15 +165,11 @@ 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
    assert_equal '1 2 3 4', @filters.join([1, 2, 3, 4])
    assert_equal '1 - 2 - 3 - 4', @filters.join([1, 2, 3, 4], ' - ')
-    assert_equal '1121314', @filters.join([1, 2, 3, 4], 1)
  end

  def test_sort
@@ -197,11 +177,6 @@ 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 +195,14 @@ 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 +226,10 @@ 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
@@ -419,29 +295,6 @@ 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
@@ -472,11 +325,11 @@ 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")
+    assert_equal nil, @filters.date(nil, "%B")

    assert_equal '', @filters.date('', "%B")

@@ -489,8 +342,8 @@ class StandardFiltersTest < Minitest::Test
  def test_first_last
    assert_equal 1, @filters.first([1, 2, 3])
    assert_equal 3, @filters.last([1, 2, 3])
-    assert_nil @filters.first([])
-    assert_nil @filters.last([])
+    assert_equal nil, @filters.first([])
+    assert_equal nil, @filters.last([])
  end

  def test_replace
@@ -630,28 +483,6 @@ 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 +523,6 @@ 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
@@ -159,7 +159,7 @@ 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%}
@@ -178,7 +178,7 @@ 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
--- 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
@@ -140,7 +137,7 @@ class IncludeTagTest < Minitest::Test

    Liquid::Template.file_system = infinite_file_system.new

-    assert_raises(Liquid::StackLevelError) do
+    assert_raises(Liquid::StackLevelError, SystemStackError) do
      Template.parse("{% include 'loop' %}").render!
    end
  end
@@ -238,16 +235,4 @@ class IncludeTagTest < Minitest::Test

    assert_template_result "Product: Draft 151cm ", "{% assign page = 'product' %}{% include page for foo %}", "foo" => { 'title' => 'Draft 151cm' }
  end
-
-  def test_including_with_strict_variables
-    template = Liquid::Template.parse("{% include 'simple' %}", error_mode: :warn)
-    template.render(nil, strict_variables: true)
-
-    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
@@ -261,15 +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
@@ -2,6 +2,7 @@

 ENV["MT_NO_EXPECTATIONS"] = "1"
 require 'minitest/autorun'
+require 'spy/integration'

 $LOAD_PATH.unshift(File.join(File.expand_path(__dir__), '..', 'lib'))
 require 'liquid.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
@@ -57,6 +57,11 @@ class ConditionUnitTest < Minitest::Test
    assert_evaluates_argument_error 1, '~~', 0
  end

+  def test_comparing_hash_and_integer
+    assert_evaluates_argument_error({a: 1}, '>', 1)
+    assert_evaluates_argument_error(1, '>', {a: 1})
+  end
+
  def test_comparation_of_int_and_str
    assert_evaluates_argument_error '1', '>', 0
    assert_evaluates_argument_error '1', '<', 0
@@ -64,14 +69,6 @@ class ConditionUnitTest < Minitest::Test
    assert_evaluates_argument_error '1', '<=', 0
  end

-  def test_hash_compare_backwards_compatibility
-    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' => 2 }, 'contains', 'a').evaluate
-  end
-
  def test_contains_works_on_arrays
    @context = Liquid::Context.new
    @context['array'] = [1, 2, 3, 4, 5]
--- a/test/unit/context_unit_test.rb
+++ b/test/unit/context_unit_test.rb
@@ -70,6 +70,10 @@ class ContextUnitTest < Minitest::Test
    @context = Liquid::Context.new
  end

+  def teardown
+    Spy.teardown
+  end
+
  def test_variables
    @context['string'] = 'string'
    assert_equal 'string', @context['string']
@@ -94,12 +98,12 @@ class ContextUnitTest < Minitest::Test
    assert_equal false, @context['bool']

    @context['nil'] = nil
-    assert_nil @context['nil']
-    assert_nil @context['nil']
+    assert_equal nil, @context['nil']
+    assert_equal nil, @context['nil']
  end

  def test_variables_not_existing
-    assert_nil @context['does_not_exist']
+    assert_equal nil, @context['does_not_exist']
  end

  def test_scoping
@@ -181,7 +185,7 @@ class ContextUnitTest < Minitest::Test
    @context['test'] = 'test'
    assert_equal 'test', @context['test']
    @context.pop
-    assert_nil @context['test']
+    assert_equal nil, @context['test']
  end

  def test_hierachical_data
@@ -296,7 +300,7 @@ class ContextUnitTest < Minitest::Test
    @context['hash'] = { 'first' => 'Hello' }

    assert_equal 1, @context['array.first']
-    assert_nil @context['array["first"]']
+    assert_equal nil, @context['array["first"]']
    assert_equal 'Hello', @context['hash["first"]']
  end

@@ -446,10 +450,14 @@ class ContextUnitTest < Minitest::Test
    assert_equal @context, @context['category'].context
  end

-  def test_interrupt_avoids_object_allocations
-    assert_no_object_allocations do
-      @context.interrupt?
-    end
+  def test_use_empty_instead_of_any_in_interrupt_handling_to_avoid_lots_of_unnecessary_object_allocations
+    mock_any = Spy.on_instance_method(Array, :any?)
+    mock_empty = Spy.on_instance_method(Array, :empty?)
+
+    @context.interrupt?
+
+    refute mock_any.has_been_called?
+    assert mock_empty.has_been_called?
  end

  def test_context_initialization_with_a_proc_in_environment
@@ -472,18 +480,4 @@ class ContextUnitTest < Minitest::Test
    context = Context.new
    assert_equal 'hi', context.apply_global_filter('hi')
  end
-
-  private
-
-  def assert_no_object_allocations
-    unless RUBY_ENGINE == 'ruby'
-      skip "stackprof needed to count object allocations"
-    end
-    require 'stackprof'
-
-    profile = StackProf.run(mode: :object) do
-      yield
-    end
-    assert_equal 0, profile[:samples]
-  end
 end # ContextTest
--- a/test/unit/lexer_unit_test.rb
+++ b/test/unit/lexer_unit_test.rb
@@ -19,7 +19,7 @@ class LexerUnitTest < Minitest::Test
  end

  def test_comparison
-    tokens = Lexer.new('== <> contains ').tokenize
+    tokens = Lexer.new('== <> contains').tokenize
    assert_equal [[:comparison, '=='], [:comparison, '<>'], [:comparison, 'contains'], [:end_of_string]], tokens
  end

--- a/test/unit/strainer_unit_test.rb
+++ b/test/unit/strainer_unit_test.rb
@@ -145,20 +145,4 @@ class StrainerUnitTest < Minitest::Test
    Strainer.global_filter(LateAddedFilter)
    assert_equal 'filtered', Strainer.create(nil).invoke('late_added_filter', 'input')
  end
-
-  def test_add_filter_does_not_include_already_included_module
-    mod = Module.new do
-      class << self
-        attr_accessor :include_count
-        def included(mod)
-          self.include_count += 1
-        end
-      end
-      self.include_count = 0
-    end
-    strainer = Context.new.strainer
-    strainer.class.add_filter(mod)
-    strainer.class.add_filter(mod)
-    assert_equal 1, mod.include_count
-  end
 end # StrainerTest