From 1310c4978d15023982b2edbf25a7f8ed86cdcd3c Mon Sep 17 00:00:00 2001
From: "Charles-P. Clermont" <charles@cpclermont.com>
Date: Fri, 11 Feb 2022 11:37:06 -0500
Subject: [PATCH] Fix kwarg parsing inconsistency with Liquid::C

Liquid::C parses liquid filter arguments with dashes in them, Liquid does not.

For tags that accept kwargs and dumps them on the HTML tag, this is an important feature.

e.g. {{ ... | image_tag: loading: 'lazy', data-something: 'value!' }}

Without this change, Liquid would incorrectly parse the
`data-something` kwarg as a single argument and would skip over the
invalid characters.

See https://github.com/Shopify/theme-check/issues/539 for more context
---
 lib/liquid.rb                         |  2 +-
 test/integration/filter_kwarg_test.rb | 24 ++++++++++++++++++++++++
 2 files changed, 25 insertions(+), 1 deletion(-)
 create mode 100644 test/integration/filter_kwarg_test.rb

diff --git a/lib/liquid.rb b/lib/liquid.rb
index 28337943..7772bb5f 100644
--- a/lib/liquid.rb
+++ b/lib/liquid.rb
@@ -36,7 +36,7 @@ module Liquid
   VariableIncompleteEnd       = /\}\}?/
   QuotedString                = /"[^"]*"|'[^']*'/
   QuotedFragment              = /#{QuotedString}|(?:[^\s,\|'"]|#{QuotedString})+/o
-  TagAttributes               = /(\w+)\s*\:\s*(#{QuotedFragment})/o
+  TagAttributes               = /(\w[\w-]*)\s*\:\s*(#{QuotedFragment})/o
   AnyStartingTag              = /#{TagStart}|#{VariableStart}/o
   PartialTemplateParser       = /#{TagStart}.*?#{TagEnd}|#{VariableStart}.*?#{VariableIncompleteEnd}/om
   TemplateParser              = /(#{PartialTemplateParser}|#{AnyStartingTag})/om
diff --git a/test/integration/filter_kwarg_test.rb b/test/integration/filter_kwarg_test.rb
new file mode 100644
index 00000000..2bd3cbdf
--- /dev/null
+++ b/test/integration/filter_kwarg_test.rb
@@ -0,0 +1,24 @@
+# frozen_string_literal: true
+
+require 'test_helper'
+
+class FilterKwargTest < Minitest::Test
+  module KwargFilter
+    def html_tag(_tag, attributes)
+      attributes
+        .map { |key, value| "#{key}='#{value}'" }
+        .join(' ')
+    end
+  end
+
+  include Liquid
+
+  def test_can_parse_data_kwargs
+    with_global_filter(KwargFilter) do
+      assert_equal(
+        "data-src='src' data-widths='100, 200'",
+        Template.parse("{{ 'img' | html_tag: data-src: 'src', data-widths: '100, 200' }}").render(nil, nil)
+      )
+    end
+  end
+end