update link paths in docs markup

fix variable lookup parse timing out with missing closing bracket

.github/workflows/liquid.yml

@@ -1,5 +1,10 @@
 name: Liquid
 on: [push, pull_request]
+
+env:
+  BUNDLE_JOBS: 4
+  BUNDLE_RETRY: 3
+
 jobs:
   test:
     runs-on: ubuntu-latest
@@ -7,22 +12,18 @@ jobs:
       matrix:
         entry:
           - { ruby: 2.7, allowed-failure: false } # minimum supported
-          - { ruby: 3.1, allowed-failure: false } # latest
+          - { ruby: 3.2, allowed-failure: false } # latest
           - { ruby: ruby-head, allowed-failure: true }
-    name: test (${{ matrix.entry.ruby }})
+    name: Test Ruby ${{ matrix.entry.ruby }}
     steps:
       - uses: actions/checkout@v3
       - uses: ruby/setup-ruby@v1
         with:
           ruby-version: ${{ matrix.entry.ruby }}
-      - uses: actions/cache@v1
-        with:
-          path: vendor/bundle
-          key: ${{ runner.os }}-gems-${{ hashFiles('Gemfile') }}
-          restore-keys: ${{ runner.os }}-gems-
-      - run: bundle install --jobs=3 --retry=3 --path=vendor/bundle
+          bundler-cache: true
       - run: bundle exec rake
         continue-on-error: ${{ matrix.entry.allowed-failure }}
+
   memory_profile:
     runs-on: ubuntu-latest
     steps:
@@ -30,10 +31,5 @@ jobs:
       - uses: ruby/setup-ruby@v1
         with:
           ruby-version: 2.7
-      - uses: actions/cache@v1
-        with:
-          path: vendor/bundle
-          key: ${{ runner.os }}-gems-${{ hashFiles('Gemfile') }}
-          restore-keys: ${{ runner.os }}-gems-
-      - run: bundle install --jobs=3 --retry=3 --path=vendor/bundle
+          bundler-cache: true
       - run: bundle exec rake memory_profile:run

Gemfile

@@ -18,6 +18,7 @@ group :benchmark, :test do
 end
 
 group :test do
+  gem 'rubocop', '~> 1.44.0'
   gem 'rubocop-shopify', '~> 2.7.0', require: false
   gem 'rubocop-performance', require: false
 

README.md

@@ -5,7 +5,7 @@
 
 * [Contributing guidelines](CONTRIBUTING.md)
 * [Version history](History.md)
-* [Liquid documentation from Shopify](https://shopify.dev/api/liquid)
+* [Liquid documentation from Shopify](https://shopify.dev/docs/docs/api/liquid)
 * [Liquid Wiki at GitHub](https://github.com/Shopify/liquid/wiki)
 * [Website](http://liquidmarkup.org/)
 

lib/liquid.rb

@@ -41,7 +41,7 @@ module Liquid
   AnyStartingTag              = /#{TagStart}|#{VariableStart}/o
   PartialTemplateParser       = /#{TagStart}.*?#{TagEnd}|#{VariableStart}.*?#{VariableIncompleteEnd}/om
   TemplateParser              = /(#{PartialTemplateParser}|#{AnyStartingTag})/om
-  VariableParser              = /\[[^\]]+\]|#{VariableSegment}+\??/o
+  VariableParser              = /\[(?>[^\[\]]+|\g<0>)*\]|#{VariableSegment}+\??/o
 
   RAISE_EXCEPTION_LAMBDA = ->(_e) { raise }
 

lib/liquid/drop.rb

@@ -25,6 +25,10 @@ module Liquid
   class Drop
     attr_writer :context
 
+    def initialize
+      @context = nil
+    end
+
     # Catch all for the method
     def liquid_method_missing(method)
       return nil unless @context&.strict_variables

lib/liquid/forloop_drop.rb

@@ -5,7 +5,7 @@ module Liquid
   # @liquid_type object
   # @liquid_name forloop
   # @liquid_summary
-  #   Information about a parent [`for` loop](/api/liquid/tags/for).
+  #   Information about a parent [`for` loop](/docs/api/liquid/tags/for).
   class ForloopDrop < Drop
     def initialize(name, length, parentloop)
       @name       = name

lib/liquid/standardfilters.rb

@@ -615,7 +615,7 @@ module Liquid
     # @liquid_description
     #   > Note:
     #   > The `concat` filter won't filter out duplicates. If you want to remove duplicates, then you need to use the
-    #   > [`uniq` filter](/api/liquid/filters/uniq).
+    #   > [`uniq` filter](/docs/api/liquid/filters/uniq).
     # @liquid_syntax array | concat: array
     # @liquid_return [array[untyped]]
     def concat(input, array)
@@ -757,7 +757,7 @@ module Liquid
     # @liquid_type filter
     # @liquid_category math
     # @liquid_summary
-    #   Divides a number by a given number.
+    #   Divides a number by a given number. The `divided_by` filter produces a result of the same type as the divisor. This means if you divide by an integer, the result will be an integer, and if you divide by a float, the result will be a float.
     # @liquid_syntax number | divided_by: number
     # @liquid_return [number]
     def divided_by(input, operand)
@@ -857,9 +857,9 @@ module Liquid
     # @liquid_summary
     #   Sets a default value for any variable whose value is one of the following:
     #
-    #   - [`empty`](/api/liquid/basics#empty)
-    #   - [`false`](/api/liquid/basics#truthy-and-falsy)
-    #   - [`nil`](/api/liquid/basics#nil)
+    #   - [`empty`](/docs/api/liquid/basics#empty)
+    #   - [`false`](/docs/api/liquid/basics#truthy-and-falsy)
+    #   - [`nil`](/docs/api/liquid/basics#nil)
     # @liquid_syntax variable | default: variable
     # @liquid_return [untyped]
     # @liquid_optional_param allow_false [boolean] Whether to use false values instead of the default.

lib/liquid/tablerowloop_drop.rb

@@ -5,7 +5,7 @@ module Liquid
   # @liquid_type object
   # @liquid_name tablerowloop
   # @liquid_summary
-  #   Information about a parent [`tablerow` loop](/api/liquid/tags/tablerow).
+  #   Information about a parent [`tablerow` loop](/docs/api/liquid/tags/tablerow).
   class TablerowloopDrop < Drop
     def initialize(length, cols)
       @length = length

lib/liquid/tags/assign.rb

@@ -8,7 +8,7 @@ module Liquid
   # @liquid_summary
   #   Creates a new variable.
   # @liquid_description
-  #   You can create variables of any [basic type](/api/liquid/basics#types), [object](/api/liquid/objects), or object property.
+  #   You can create variables of any [basic type](/docs/api/liquid/basics#types), [object](/docs/api/liquid/objects), or object property.
   # @liquid_syntax
   #   {% assign variable_name = value %}
   # @liquid_syntax_keyword variable_name The name of the variable being created.

lib/liquid/tags/break.rb

@@ -15,7 +15,7 @@ module Liquid
   # @liquid_category iteration
   # @liquid_name break
   # @liquid_summary
-  #   Stops a [`for` loop](/api/liquid/tags/for) from iterating.
+  #   Stops a [`for` loop](/docs/api/liquid/tags/for) from iterating.
   # @liquid_syntax
   #   {% break %}
   class Break < Tag

lib/liquid/tags/continue.rb

@@ -6,7 +6,7 @@ module Liquid
   # @liquid_category iteration
   # @liquid_name continue
   # @liquid_summary
-  #   Causes a [`for` loop](/api/liquid/tags/for) to skip to the next iteration.
+  #   Causes a [`for` loop](/docs/api/liquid/tags/for) to skip to the next iteration.
   # @liquid_syntax
   #   {% continue %}
   class Continue < Tag

lib/liquid/tags/cycle.rb

@@ -6,7 +6,7 @@ module Liquid
   # @liquid_category iteration
   # @liquid_name cycle
   # @liquid_summary
-  #   Loops through a group of strings and outputs them one at a time for each iteration of a [`for` loop](/api/liquid/tags/for).
+  #   Loops through a group of strings and outputs them one at a time for each iteration of a [`for` loop](/docs/api/liquid/tags/for).
   # @liquid_description
   #   The `cycle` tag must be used inside a `for` loop.
   #

lib/liquid/tags/decrement.rb

@@ -12,8 +12,8 @@ module Liquid
   #   or [section](/themes/architecture/sections) file that they're created in. However, the variable is shared across
   #   [snippets](/themes/architecture#snippets) included in the file.
   #
-  #   Similarly, variables that are created with `decrement` are independent from those created with [`assign`](/api/liquid/tags/assign)
-  #   and [`capture`](/api/liquid/tags/capture). However, `decrement` and [`increment`](/api/liquid/tags/increment) share
+  #   Similarly, variables that are created with `decrement` are independent from those created with [`assign`](/docs/api/liquid/tags/assign)
+  #   and [`capture`](/docs/api/liquid/tags/capture). However, `decrement` and [`increment`](/docs/api/liquid/tags/increment) share
   #   variables.
   # @liquid_syntax
   #   {% decrement variable_name %}

lib/liquid/tags/echo.rb

@@ -9,10 +9,10 @@ module Liquid
   #   Outputs an expression.
   # @liquid_description
   #   Using the `echo` tag is the same as wrapping an expression in curly brackets (`{{` and `}}`). However, unlike the curly
-  #   bracket method, you can use the `echo` tag inside [`liquid` tags](/api/liquid/tags/liquid).
+  #   bracket method, you can use the `echo` tag inside [`liquid` tags](/docs/api/liquid/tags/liquid).
   #
   #   > Tip:
-  #   > You can use [filters](/api/liquid/filters) on expressions inside `echo` tags.
+  #   > You can use [filters](/docs/api/liquid/filters) on expressions inside `echo` tags.
   # @liquid_syntax
   #   {% liquid
   #     echo expression

lib/liquid/tags/for.rb

@@ -9,10 +9,10 @@ module Liquid
   #   Renders an expression for every item in an array.
   # @liquid_description
   #   You can do a maximum of 50 iterations with a `for` loop. If you need to iterate over more than 50 items, then use the
-  #   [`paginate` tag](/api/liquid/tags/paginate) to split the items over multiple pages.
+  #   [`paginate` tag](/docs/api/liquid/tags/paginate) to split the items over multiple pages.
   #
   #   > Tip:
-  #   > Every `for` loop has an associated [`forloop` object](/api/liquid/objects/forloop) with information about the loop.
+  #   > Every `for` loop has an associated [`forloop` object](/docs/api/liquid/objects/forloop) with information about the loop.
   # @liquid_syntax
   #   {% for variable in array %}
   #     expression
@@ -98,11 +98,12 @@ module Liquid
       @name     = "#{@variable_name}-#{collection_name}"
       @reversed = p.id?('reversed')
 
-      while p.look(:id) && p.look(:colon, 1)
+      while p.look(:comma) || p.look(:id)
+        p.consume?(:comma)
         unless (attribute = p.id?('limit') || p.id?('offset'))
           raise SyntaxError, options[:locale].t("errors.syntax.for_invalid_attribute")
         end
-        p.consume
+        p.consume(:colon)
         set_attribute(attribute, p.expression)
       end
       p.consume(:end_of_string)

lib/liquid/tags/include.rb

@@ -8,7 +8,7 @@ module Liquid
   # @liquid_summary
   #   Renders a [snippet](/themes/architecture#snippets).
   # @liquid_description
-  #   Inside the snippet, you can access and alter variables that are [created](/api/liquid/tags/variable-tags) outside of the
+  #   Inside the snippet, you can access and alter variables that are [created](/docs/api/liquid/tags/variable-tags) outside of the
   #   snippet.
   # @liquid_syntax
   #   {% include 'filename' %}
@@ -16,7 +16,7 @@ module Liquid
   # @liquid_deprecated
   #   Deprecated because the way that variables are handled reduces performance and makes code harder to both read and maintain.
   #
-  #   The `include` tag has been replaced by [`render`](/api/liquid/tags/render).
+  #   The `include` tag has been replaced by [`render`](/docs/api/liquid/tags/render).
   class Include < Tag
     prepend Tag::Disableable
 

lib/liquid/tags/increment.rb

@@ -12,8 +12,8 @@ module Liquid
   #   or [section](/themes/architecture/sections) file that they're created in. However, the variable is shared across
   #   [snippets](/themes/architecture#snippets) included in the file.
   #
-  #   Similarly, variables that are created with `increment` are independent from those created with [`assign`](/api/liquid/tags/assign)
-  #   and [`capture`](/api/liquid/tags/capture). However, `increment` and [`decrement`](/api/liquid/tags/decrement) share
+  #   Similarly, variables that are created with `increment` are independent from those created with [`assign`](/docs/api/liquid/tags/assign)
+  #   and [`capture`](/docs/api/liquid/tags/capture). However, `increment` and [`decrement`](/docs/api/liquid/tags/decrement) share
   #   variables.
   # @liquid_syntax
   #   {% increment variable_name %}

lib/liquid/tags/raw.rb

@@ -14,7 +14,7 @@ module Liquid
   # @liquid_syntax_keyword expression The expression to be output without being rendered.
   class Raw < Block
     Syntax = /\A\s*\z/
-    FullTokenPossiblyInvalid = /\A(.*)#{TagStart}\s*(\w+)\s*(.*)?#{TagEnd}\z/om
+    FullTokenPossiblyInvalid = /\A(.*)#{TagStart}#{WhitespaceControl}?\s*(\w+)\s*(.*)?#{WhitespaceControl}?#{TagEnd}\z/om
 
     def initialize(tag_name, markup, parse_context)
       super

lib/liquid/tags/render.rb

@@ -8,19 +8,19 @@ module Liquid
   # @liquid_summary
   #   Renders a [snippet](/themes/architecture#snippets) or [app block](/themes/architecture/sections/section-schema#render-app-blocks).
   # @liquid_description
-  #   Inside snippets and app blocks, you can't directly access variables that are [created](/api/liquid/tags/variable-tags) outside
-  #   of the snippet or app block. However, you can [specify variables as parameters](/api/liquid/tags/render#render-passing-variables-to-a-snippet)
+  #   Inside snippets and app blocks, you can't directly access variables that are [created](/docs/api/liquid/tags/variable-tags) outside
+  #   of the snippet or app block. However, you can [specify variables as parameters](/docs/api/liquid/tags/render#render-passing-variables-to-a-snippet)
   #   to pass outside variables to snippets.
   #
   #   While you can't directly access created variables, you can access global objects, as well as any objects that are
   #   directly accessible outside the snippet or app block. For example, a snippet or app block inside the [product template](/themes/architecture/templates/product)
-  #   can access the [`product` object](/api/liquid/objects/product), and a snippet or app block inside a [section](/themes/architecture/sections)
-  #   can access the [`section` object](/api/liquid/objects/section).
+  #   can access the [`product` object](/docs/api/liquid/objects/product), and a snippet or app block inside a [section](/themes/architecture/sections)
+  #   can access the [`section` object](/docs/api/liquid/objects/section).
   #
   #   Outside a snippet or app block, you can't access variables created inside the snippet or app block.
   #
   #   > Note:
-  #   > When you render a snippet using the `render` tag, you can't use the [`include` tag](/api/liquid/tags/include)
+  #   > When you render a snippet using the `render` tag, you can't use the [`include` tag](/docs/api/liquid/tags/include)
   #   > inside the snippet.
   # @liquid_syntax
   #   {% render 'filename' %}

lib/liquid/tags/table_row.rb

@@ -11,7 +11,7 @@ module Liquid
   #   The `tablerow` tag must be wrapped in HTML `<table>` and `</table>` tags.
   #
   #   > Tip:
-  #   > Every `tablerow` loop has an associated [`tablerowloop` object](/api/liquid/objects/tablerowloop) with information about the loop.
+  #   > Every `tablerow` loop has an associated [`tablerowloop` object](/docs/api/liquid/objects/tablerowloop) with information about the loop.
   # @liquid_syntax
   #   {% tablerow variable in array %}
   #     expression
@@ -45,13 +45,13 @@ module Liquid
     def render_to_output_buffer(context, output)
       (collection = context.evaluate(@collection_name)) || (return '')
 
-      from = @attributes.key?('offset') ? context.evaluate(@attributes['offset']).to_i : 0
-      to   = @attributes.key?('limit')  ? from + context.evaluate(@attributes['limit']).to_i : nil
+      from = @attributes.key?('offset') ? to_integer(context.evaluate(@attributes['offset'])) : 0
+      to = @attributes.key?('limit') ? from + to_integer(context.evaluate(@attributes['limit'])) : nil
 
       collection = Utils.slice_collection(collection, from, to)
       length     = collection.length
 
-      cols = @attributes.key?('cols') ? context.evaluate(@attributes['cols']).to_i : length
+      cols = @attributes.key?('cols') ? to_integer(context.evaluate(@attributes['cols'])) : length
 
       output << "<tr class=\"row1\">\n"
       context.stack do
@@ -82,6 +82,14 @@ module Liquid
         super + @node.attributes.values + [@node.collection_name]
       end
     end
+
+    private
+
+    def to_integer(value)
+      value.to_i
+    rescue NoMethodError
+      raise Liquid::ArgumentError, "invalid integer"
+    end
   end
 
   Template.register_tag('tablerow', TableRow)

lib/liquid/tags/unless.rb

@@ -11,7 +11,7 @@ module Liquid
   #   Renders an expression unless a specific condition is `true`.
   # @liquid_description
   #   > Tip:
-  #   > Similar to the [`if` tag](/api/liquid/tags/if), you can use `elsif` to add more conditions to an `unless` tag.
+  #   > Similar to the [`if` tag](/docs/api/liquid/tags/if), you can use `elsif` to add more conditions to an `unless` tag.
   # @liquid_syntax
   #   {% unless condition %}
   #     expression

lib/liquid/utils.rb

@@ -16,7 +16,11 @@ module Liquid
 
       # Maintains Ruby 1.8.7 String#each behaviour on 1.9
       if collection.is_a?(String)
-        return collection.empty? ? [] : [collection]
+        return [] if collection.empty?
+        if from > 0 || to == 0
+          Usage.increment("string_slice_bug")
+        end
+        return [collection]
       end
       return [] unless collection.respond_to?(:each)
 

performance/shopify/database.rb

@@ -49,8 +49,3 @@ module Database
     end
   end
 end
-
-if __FILE__ == $PROGRAM_NAME
-  p(Database.tables['collections']['frontpage'].keys)
-  # p Database.tables['blog']['articles']
-end

test/integration/context_test.rb

@@ -262,7 +262,7 @@ class ContextTest < Minitest::Test
     assigns = { 'product' => { 'variants' => [{ 'title' => 'draft151cm' }, { 'title' => 'element151cm' }] } }
     assert_template_result("draft151cm", '{{ product["variants"][0]["title"] }}', assigns)
     assert_template_result("element151cm", '{{ product["variants"][1]["title"] }}', assigns)
-    assert_template_result("draft151cm", '{{ product["variants"][0]["title"] }}', assigns)
+    assert_template_result("draft151cm", '{{ product["variants"].first["title"] }}', assigns)
     assert_template_result("element151cm", '{{ product["variants"].last["title"] }}', assigns)
   end
 

test/integration/tags/for_tag_test.rb

@@ -103,6 +103,7 @@ HERE
     assert_template_result('1234', '{%for i in array limit:4 %}{{ i }}{%endfor%}', assigns)
     assert_template_result('3456', '{%for i in array limit:4 offset:2 %}{{ i }}{%endfor%}', assigns)
     assert_template_result('3456', '{%for i in array limit: 4 offset: 2 %}{{ i }}{%endfor%}', assigns)
+    assert_template_result('3456', '{%for i in array, limit: 4, offset: 2 %}{{ i }}{%endfor%}', assigns)
   end
 
   def test_limiting_with_invalid_limit

test/integration/tags/if_else_tag_test.rb

@@ -62,7 +62,7 @@ class IfElseTagTest < Minitest::Test
   def test_if_and
     assert_template_result(' YES ', '{% if true and true %} YES {% endif %}')
     assert_template_result('', '{% if false and true %} YES {% endif %}')
-    assert_template_result('', '{% if false and true %} YES {% endif %}')
+    assert_template_result('', '{% if true and false %} YES {% endif %}')
   end
 
   def test_hash_miss_generates_false

test/integration/tags/raw_tag_test.rb

@@ -11,7 +11,8 @@ class RawTagTest < Minitest::Test
   end
 
   def test_output_in_raw
-    assert_template_result('{{ test }}', '{% raw %}{{ test }}{% endraw %}')
+    # assert_template_result('{{ test }}', '{% raw %}{{ test }}{% endraw %}')
+    assert_template_result('>{{ test }}<', '> {%- raw -%}{{ test }}{%- endraw -%} <')
   end
 
   def test_open_tag_in_raw

test/integration/tags/table_row_test.rb

@@ -80,6 +80,32 @@ class TableRowTest < Minitest::Test
       { "var" => nil })
   end
 
+  def test_nil_limit_is_treated_as_zero
+    expect = "<tr class=\"row1\">\n" \
+      "</tr>\n"
+
+    assert_template_result(expect,
+      "{% tablerow i in (1..2) limit:nil %}{{ i }}{% endtablerow %}")
+
+    assert_template_result(expect,
+      "{% tablerow i in (1..2) limit:var %}{{ i }}{% endtablerow %}",
+      { "var" => nil })
+  end
+
+  def test_nil_offset_is_treated_as_zero
+    expect = "<tr class=\"row1\">\n" \
+      "<td class=\"col1\">1:false</td>" \
+      "<td class=\"col2\">2:true</td>" \
+      "</tr>\n"
+
+    assert_template_result(expect,
+      "{% tablerow i in (1..2) offset:nil %}{{ i }}:{{ tablerowloop.col_last }}{% endtablerow %}")
+
+    assert_template_result(expect,
+      "{% tablerow i in (1..2) offset:var %}{{ i }}:{{ tablerowloop.col_last }}{% endtablerow %}",
+      { "var" => nil })
+  end
+
   def test_tablerow_loop_drop_attributes
     template = <<~LIQUID.chomp
       {% tablerow i in (1...2) %}
@@ -131,4 +157,24 @@ class TableRowTest < Minitest::Test
 
     assert_template_result(expected_output, template)
   end
+
+  def test_table_row_renders_correct_error_message_for_invalid_parameters
+    assert_template_result(
+      "Liquid error (line 1): invalid integer",
+      '{% tablerow n in (1...10) limit:true %} {{n}} {% endtablerow %}',
+      render_errors: true,
+    )
+
+    assert_template_result(
+      "Liquid error (line 1): invalid integer",
+      '{% tablerow n in (1...10) offset:true %} {{n}} {% endtablerow %}',
+      render_errors: true,
+    )
+
+    assert_template_result(
+      "Liquid error (line 1): invalid integer",
+      '{% tablerow n in (1...10) cols:true %} {{n}} {% endtablerow %}',
+      render_errors: true,
+    )
+  end
 end

test/integration/variable_test.rb

@@ -1,6 +1,7 @@
 # frozen_string_literal: true
 
 require 'test_helper'
+require 'timeout'
 
 class VariableTest < Minitest::Test
   include Liquid
@@ -24,17 +25,22 @@ class VariableTest < Minitest::Test
 
   def test_if_tag_calls_to_liquid_value
     assert_template_result('one', '{% if foo == 1 %}one{% endif %}', { 'foo' => IntegerDrop.new('1') })
+    assert_template_result('one', '{% if foo == eqv %}one{% endif %}', { 'foo' => IntegerDrop.new(1), 'eqv' => IntegerDrop.new(1) })
     assert_template_result('one', '{% if 0 < foo %}one{% endif %}', { 'foo' => IntegerDrop.new('1') })
     assert_template_result('one', '{% if foo > 0 %}one{% endif %}', { 'foo' => IntegerDrop.new('1') })
+    assert_template_result('one', '{% if b > a %}one{% endif %}', { 'b' => IntegerDrop.new(1), 'a' => IntegerDrop.new(0) })
     assert_template_result('true', '{% if foo == true %}true{% endif %}', { 'foo' => BooleanDrop.new(true) })
     assert_template_result('true', '{% if foo %}true{% endif %}', { 'foo' => BooleanDrop.new(true) })
 
     assert_template_result('', '{% if foo %}true{% endif %}', { 'foo' => BooleanDrop.new(false) })
     assert_template_result('', '{% if foo == true %}True{% endif %}', { 'foo' => BooleanDrop.new(false) })
+
+    assert_template_result('one', '{% if a contains x %}one{% endif %}', { 'a' => [1], 'x' => IntegerDrop.new(1) })
   end
 
   def test_unless_tag_calls_to_liquid_value
     assert_template_result('', '{% unless foo %}true{% endunless %}', { 'foo' => BooleanDrop.new(true) })
+    assert_template_result('true', '{% unless foo %}true{% endunless %}', { 'foo' => BooleanDrop.new(false) })
   end
 
   def test_case_tag_calls_to_liquid_value
@@ -130,4 +136,72 @@ class VariableTest < Minitest::Test
   def test_raw_value_variable
     assert_template_result('bar', '{{ [key] }}', { 'key' => 'foo', 'foo' => 'bar' })
   end
+
+  def test_dynamic_find_var_with_drop
+    assert_template_result(
+      'bar',
+      '{{ [list[settings.zero]] }}',
+      {
+        'list' => ['foo'],
+        'settings' => SettingsDrop.new("zero" => 0),
+        'foo' => 'bar',
+      }
+    )
+
+    assert_template_result(
+      'foo',
+      '{{ [list[settings.zero]["foo"]] }}',
+      {
+        'list' => [{ 'foo' => 'bar' }],
+        'settings' => SettingsDrop.new("zero" => 0),
+        'bar' => 'foo',
+      }
+    )
+  end
+
+  def test_double_nested_variable_lookup
+    assert_template_result(
+      'bar',
+      '{{ list[list[settings.zero]]["foo"] }}',
+      {
+        'list' => [1, { 'foo' => 'bar' }],
+        'settings' => SettingsDrop.new("zero" => 0),
+        'bar' => 'foo',
+      }
+    )
+  end
+
+  def test_variable_lookup_should_not_hang_with_invalid_syntax
+    Timeout.timeout(1) do
+      assert_template_result(
+        'bar',
+        "{{['foo'}}",
+        {
+          'foo' => 'bar',
+        },
+        error_mode: :lax,
+      )
+    end
+
+    very_long_key = "1234567890" * 100
+
+    template_list = [
+      "{{['#{very_long_key}']}}", # valid
+      "{{['#{very_long_key}'}}", # missing closing bracket
+      "{{[['#{very_long_key}']}}", # extra open bracket
+    ]
+
+    template_list.each do |template|
+      Timeout.timeout(1) do
+        assert_template_result(
+          'bar',
+          template,
+          {
+            very_long_key => 'bar',
+          },
+          error_mode: :lax,
+        )
+      end
+    end
+  end
 end

test/test_helper.rb

@@ -125,16 +125,23 @@ class ThingWithToLiquid
   end
 end
 
+class SettingsDrop < Liquid::Drop
+  def initialize(settings)
+    super()
+    @settings = settings
+  end
+
+  def liquid_method_missing(key)
+    @settings[key]
+  end
+end
+
 class IntegerDrop < Liquid::Drop
   def initialize(value)
     super()
     @value = value.to_i
   end
 
-  def ==(other)
-    @value == other
-  end
-
   def to_s
     @value.to_s
   end
@@ -150,10 +157,6 @@ class BooleanDrop < Liquid::Drop
     @value = value
   end
 
-  def ==(other)
-    @value == other
-  end
-
   def to_liquid_value
     @value
   end

test/unit/regexp_unit_test.rb

@@ -1,6 +1,7 @@
 # frozen_string_literal: true
 
 require 'test_helper'
+require 'timeout'
 
 class RegexpUnitTest < Minitest::Test
   include Liquid
@@ -37,10 +38,22 @@ class RegexpUnitTest < Minitest::Test
 
   def test_variable_parser
     assert_equal(['var'],                               'var'.scan(VariableParser))
+    assert_equal(['[var]'],                             '[var]'.scan(VariableParser))
     assert_equal(['var', 'method'],                     'var.method'.scan(VariableParser))
     assert_equal(['var', '[method]'],                   'var[method]'.scan(VariableParser))
     assert_equal(['var', '[method]', '[0]'],            'var[method][0]'.scan(VariableParser))
     assert_equal(['var', '["method"]', '[0]'],          'var["method"][0]'.scan(VariableParser))
     assert_equal(['var', '[method]', '[0]', 'method'],  'var[method][0].method'.scan(VariableParser))
   end
+
+  def test_variable_parser_with_large_input
+    Timeout.timeout(1) { assert_equal(['[var]'], '[var]'.scan(VariableParser)) }
+
+    very_long_string = "foo" * 1000
+
+    # valid dynamic lookup
+    Timeout.timeout(1) { assert_equal(["[#{very_long_string}]"], "[#{very_long_string}]".scan(VariableParser)) }
+    # invalid dynamic lookup with missing closing bracket
+    Timeout.timeout(1) { assert_equal([very_long_string], "[#{very_long_string}".scan(VariableParser)) }
+  end
 end # RegexpTest

test/unit/tags/for_tag_unit_test.rb

@@ -12,4 +12,34 @@ class ForTagUnitTest < Minitest::Test
     template = Liquid::Template.parse('{% for item in items %}FOR{% else %}ELSE{% endfor %}')
     assert_equal(['FOR', 'ELSE'], template.root.nodelist[0].nodelist.map(&:nodelist).flatten)
   end
+
+  def test_for_string_slice_bug_usage
+    template = Liquid::Template.parse("{% for x in str, offset: 1 %}{{ x }},{% endfor %}")
+    assert_usage("string_slice_bug") do
+      assert_equal("abc,", template.render({ "str" => "abc" }))
+    end
+  end
+
+  def test_for_string_0_limit_usage
+    template = Liquid::Template.parse("{% for x in str, limit: 0 %}{{ x }},{% endfor %}")
+    assert_usage("string_slice_bug") do
+      assert_equal("abc,", template.render({ "str" => "abc" }))
+    end
+  end
+
+  def test_for_string_no_slice_usage
+    template = Liquid::Template.parse("{% for x in str, offset: 0, limit: 1 %}{{ x }},{% endfor %}")
+    assert_usage("string_slice_bug", times: 0) do
+      assert_equal("abc,", template.render({ "str" => "abc" }))
+    end
+  end
+
+  private
+
+  def assert_usage(name, times: 1, &block)
+    count = 0
+    result = Liquid::Usage.stub(:increment, ->(n) { count += 1 if n == name }, &block)
+    assert_equal(times, count)
+    result
+  end
 end