From e46de3b6ab3815dd86aca6154cda160ce6244005 Mon Sep 17 00:00:00 2001
From: "Charles-P. Clermont" <charles@cpclermont.com>
Date: Tue, 30 Sep 2025 09:18:40 -0400
Subject: [PATCH] --wip-- [skip ci]

---
 lib/liquid/parser_switching.rb          | 18 ++++++++-
 lib/liquid/tags/cycle.rb                | 54 +++++++++++++++++++------
 lib/liquid/template.rb                  |  1 +
 test/integration/tags/cycle_tag_test.rb | 15 +++++++
 4 files changed, 75 insertions(+), 13 deletions(-)

diff --git a/lib/liquid/parser_switching.rb b/lib/liquid/parser_switching.rb
index 78afd58a..55f21b79 100644
--- a/lib/liquid/parser_switching.rb
+++ b/lib/liquid/parser_switching.rb
@@ -2,10 +2,17 @@
 
 module Liquid
   module ParserSwitching
+    # We want "rigid" which is like strict but more strict only in some cases.
+    # We want to make it so strict behaves as is
+    # We want "rigid" to be stricter (prob beta flag)
+    # It shouldn't be slower to run rigid than strict, it's not rigid -> strict -> lax
+    # It's rigid -> lax or it's strict -> lax
     def strict_parse_with_error_mode_fallback(markup)
-      strict_parse_with_error_context(markup)
+      rigid_parse_with_error_context(markup)
     rescue SyntaxError => e
       case parse_context.error_mode
+      when :rigid
+        raise
       when :strict
         raise
       when :warn
@@ -16,6 +23,7 @@ module Liquid
 
     def parse_with_selected_parser(markup)
       case parse_context.error_mode
+      when :rigid  then rigid_parse_with_error_context(markup)
       when :strict then strict_parse_with_error_context(markup)
       when :lax    then lax_parse(markup)
       when :warn
@@ -30,6 +38,14 @@ module Liquid
 
     private
 
+    def rigid_parse_with_error_context(markup)
+      respond_to?(:rigid_parse) ? rigid_parse(markup) : strict_parse(markup)
+    rescue SyntaxError => e
+      e.line_number    = line_number
+      e.markup_context = markup_context(markup)
+      raise e
+    end
+
     def strict_parse_with_error_context(markup)
       strict_parse(markup)
     rescue SyntaxError => e
diff --git a/lib/liquid/tags/cycle.rb b/lib/liquid/tags/cycle.rb
index c2d94d5f..e575265c 100644
--- a/lib/liquid/tags/cycle.rb
+++ b/lib/liquid/tags/cycle.rb
@@ -22,18 +22,7 @@ module Liquid
 
     def initialize(tag_name, markup, options)
       super
-      case markup
-      when NamedSyntax
-        @variables = variables_from_string(Regexp.last_match(2))
-        @name      = parse_expression(Regexp.last_match(1))
-        @is_named = true
-      when SimpleSyntax
-        @variables = variables_from_string(markup)
-        @name      = @variables.to_s
-        @is_named = !@name.match?(/\w+:0x\h{8}/)
-      else
-        raise SyntaxError, options[:locale].t("errors.syntax.cycle")
-      end
+      parse_with_selected_parser(markup)
     end
 
     def named?
@@ -65,6 +54,47 @@ module Liquid
 
     private
 
+    # cycle [name:] expression(, expression)*
+    def rigid_parse(markup)
+      $stderr.puts "using rigid"
+      p = @parse_context.new_parser(markup)
+
+      if p.look(:id) && p.peek(1) == :colon
+        @name = p.consume(:id)
+        @is_named = true
+        p.consume(:colon)
+      end
+
+      @variables = []
+      while (var = p.expression)
+        @variables << var
+        break unless p.consume?(:comma)
+      end
+
+      raise_syntax_error(options) if @variables.empty?
+    end
+
+    # Temporarily until we migrate
+    def strict_parse(markup)
+      $stderr.puts "using rigid"
+      lax_parse(markup)
+    end
+
+    def lax_parse(markup)
+      case markup
+      when NamedSyntax
+        @variables = variables_from_string(Regexp.last_match(2))
+        @name      = parse_expression(Regexp.last_match(1))
+        @is_named = true
+      when SimpleSyntax
+        @variables = variables_from_string(markup)
+        @name      = @variables.to_s
+        @is_named = !@name.match?(/\w+:0x\h{8}/)
+      else
+        raise SyntaxError, options[:locale].t("errors.syntax.cycle")
+      end
+    end
+
     def variables_from_string(markup)
       markup.split(',').collect do |var|
         var =~ /\s*(#{QuotedFragment})\s*/o
diff --git a/lib/liquid/template.rb b/lib/liquid/template.rb
index a6d80e0a..8602745e 100644
--- a/lib/liquid/template.rb
+++ b/lib/liquid/template.rb
@@ -25,6 +25,7 @@ module Liquid
       # :lax acts like liquid 2.5 and silently ignores malformed tags in most cases.
       # :warn is the default and will give deprecation warnings when invalid syntax is used.
       # :strict will enforce correct syntax.
+      # :rigid will is stricter even.
       def error_mode=(mode)
         Deprecations.warn("Template.error_mode=", "Environment#error_mode=")
         Environment.default.error_mode = mode
diff --git a/test/integration/tags/cycle_tag_test.rb b/test/integration/tags/cycle_tag_test.rb
index a034db17..8cd6daac 100644
--- a/test/integration/tags/cycle_tag_test.rb
+++ b/test/integration/tags/cycle_tag_test.rb
@@ -45,4 +45,19 @@ class CycleTagTest < Minitest::Test
 
     assert_template_result("11", template)
   end
+
+  def test_cycle_tag_with_error_mode
+    # QuotedFragment is more permissive than what Parser#expression allows.
+    [:lax, :strict].each do |mode|
+      with_error_mode(mode) do
+        assert_template_result("a", "{% cycle .5: 'a', 'b' %}")
+        assert_template_result("b", "{% assign 5 = 'b' %}{% cycle .5, .4 %}")
+      end
+    end
+
+    with_error_mode(:rigid) do
+      assert_raises(Liquid::SyntaxError) { Template.parse("{% cycle .5: 'a', 'b' %}") }
+      assert_raises(Liquid::SyntaxError) { Template.parse("{% cycle .5, .4 %}") }
+    end
+  end
 end