From 96a44927b53b16b84826292b30aac5ce574553c0 Mon Sep 17 00:00:00 2001
From: Julia Boutin <julia.boutin@shopify.com>
Date: Tue, 21 Oct 2025 16:53:15 -0600
Subject: [PATCH] Support prop spreading

---
 lib/liquid/parser.rb                  |   8 +
 lib/liquid/tags/render.rb             |  60 ++++--
 test/integration/tags/snippet_test.rb | 274 ++++++++++++++++++++++++++
 3 files changed, 329 insertions(+), 13 deletions(-)

diff --git a/lib/liquid/parser.rb b/lib/liquid/parser.rb
index 645dfa3a..93cda908 100644
--- a/lib/liquid/parser.rb
+++ b/lib/liquid/parser.rb
@@ -12,6 +12,14 @@ module Liquid
       @p = point
     end
 
+    def read(type = nil)
+      token = @tokens[@p]
+      if type && token[0] != type
+        raise SyntaxError, "Expected #{type} but found #{@tokens[@p].first}"
+      end
+      token[1]
+    end
+
     def consume(type = nil)
       token = @tokens[@p]
       if type && token[0] != type
diff --git a/lib/liquid/tags/render.rb b/lib/liquid/tags/render.rb
index 3e9237f7..177c8f4d 100644
--- a/lib/liquid/tags/render.rb
+++ b/lib/liquid/tags/render.rb
@@ -76,10 +76,25 @@ module Liquid
         inner_context['forloop'] = forloop if forloop
 
         @attributes.each do |key, value|
-          if key == "..." && is_inline
-            context.scopes.each do |scope|
-              scope.each do |k, v|
-                inner_context[k] = v
+          if key.start_with?("...") && is_inline
+            if key == "..."
+              context.scopes.each do |scope|
+                scope.each do |k, v|
+                  inner_context[k] = v
+                end
+              end
+            else
+              obj = context.evaluate(value)
+              if obj.is_a?(Liquid::Drop)
+                (obj.class.invokable_methods - ['to_liquid']).each do |method_name|
+                  inner_context[method_name] = obj.invoke_drop(method_name)
+                end
+              elsif obj.is_a?(Hash)
+                obj.each do |k, v|
+                  inner_context[k] = v
+                end
+              else
+                raise ::ArgumentError
               end
             end
           else
@@ -117,11 +132,24 @@ module Liquid
       p.consume?(:comma)
 
       @attributes = {}
-      while p.look(:id)
-        key = p.consume
-        p.consume(:colon)
-        @attributes[key] = safe_parse_expression(p)
-        p.consume?(:comma)
+      while p.look(:dotdotdot) || p.look(:id)
+        if p.consume?(:dotdotdot)
+          if p.look(:id)
+            identifier = p.read(:id)
+            key = "...#{identifier}"
+            @attributes.delete(key)
+            @attributes[key] = safe_parse_expression(p)
+          else
+            @attributes.delete("...")
+            @attributes["..."] = true
+          end
+        else
+          key = p.consume
+          p.consume(:colon)
+          @attributes.delete(key)
+          @attributes[key] = safe_parse_expression(p)
+        end
+        p.consume?(:comma) # optional comma
       end
 
       p.consume(:end_of_string)
@@ -150,10 +178,16 @@ module Liquid
       @is_for_loop = (with_or_for == FOR)
 
       @attributes = {}
-      markup.scan(/(\.\.\.)(?=\s|,|$)|#{TagAttributes.source}/) do |context_marker, key, value|
-        if context_marker
-          @attributes.delete("...")
-          @attributes["..."] = true
+      markup.scan(/(\.\.\.)(\w+)?(?=\s|,|$)|#{TagAttributes.source}/) do |spread, identifier, key, value|
+        if spread
+          if identifier
+            spread_key = "...#{identifier}"
+            @attributes.delete(spread_key)
+            @attributes[spread_key] = parse_expression(identifier)
+          else
+            @attributes.delete("...")
+            @attributes["..."] = true
+          end
         elsif key && value
           @attributes.delete(key)
           @attributes[key] = parse_expression(value)
diff --git a/test/integration/tags/snippet_test.rb b/test/integration/tags/snippet_test.rb
index 4906437d..8830285a 100644
--- a/test/integration/tags/snippet_test.rb
+++ b/test/integration/tags/snippet_test.rb
@@ -446,6 +446,154 @@ class SnippetTest < Minitest::Test
       assert_template_result(expected, template)
     end
 
+    def test_render_inline_snippet_with_spread_hash
+      template = <<~LIQUID.strip
+        {% snippet header %}
+        <div>
+          {{ word }} {{ number }}
+        </div>
+        {% endsnippet %}
+
+        {% render header, ...details %}
+      LIQUID
+
+      expected = <<~OUTPUT
+
+
+
+        <div>
+          potato 5
+        </div>
+      OUTPUT
+
+      assert_template_result(expected, template, { 'details' => { 'word' => 'potato', 'number' => 5 } })
+    end
+
+    def test_render_inline_snippet_with_spread_drop
+      product_drop = Class.new(Liquid::Drop) do
+        def title
+          'Cool Product'
+        end
+
+        def price
+          99
+        end
+
+        def vendor
+          'Acme'
+        end
+      end
+
+      template = <<~LIQUID.strip
+        {% snippet card %}
+        <div>
+          {{ title }} - ${{ price }} by {{ vendor }}
+        </div>
+        {% endsnippet %}
+
+        {% render card, ...product %}
+      LIQUID
+
+      expected = <<~OUTPUT
+
+
+
+        <div>
+          Cool Product - $99 by Acme
+        </div>
+      OUTPUT
+
+      assert_template_result(expected, template, { 'product' => product_drop.new })
+    end
+
+    def test_render_inline_snippet_with_overwritten_spread_drop
+      product_drop = Class.new(Liquid::Drop) do
+        def title
+          'Cool Product'
+        end
+
+        def price
+          99
+        end
+
+        def vendor
+          'Acme'
+        end
+      end
+
+      template = <<~LIQUID.strip
+        {% snippet card %}
+        <div>
+          {{ title }} - ${{ price }} by {{ vendor }}
+        </div>
+        {% endsnippet %}
+
+        {% render card, ...product, price: 10 %}
+      LIQUID
+
+      expected = <<~OUTPUT
+
+
+
+        <div>
+          Cool Product - $10 by Acme
+        </div>
+      OUTPUT
+
+      assert_template_result(expected, template, { 'product' => product_drop.new })
+    end
+
+    def test_render_inline_snippet_spread_before_explicit_args
+      template = <<~LIQUID.strip
+        {% snippet card %}
+        <div>{{ price }}</div>
+        {% endsnippet %}
+
+        {% render card, ...details, price: 10 %}
+      LIQUID
+
+      expected = <<~OUTPUT
+
+
+
+        <div>10</div>
+      OUTPUT
+
+      assert_template_result(expected, template, { 'details' => { 'price' => 99 } })
+    end
+
+    def test_render_inline_snippet_multiple_spreads
+      product_drop = Class.new(Liquid::Drop) do
+        def title
+          'Cool Product'
+        end
+      end
+
+      template = <<~LIQUID.strip
+        {% snippet card %}
+        <div>{{ title }} - {{ price }} {{ color }}</div>
+        {% endsnippet %}
+
+        {% render card, ...defaults, ...product %}
+      LIQUID
+
+      expected = <<~OUTPUT
+
+
+
+        <div>Cool Product - 10 </div>
+      OUTPUT
+
+      assert_template_result(
+        expected,
+        template,
+        {
+          'defaults' => { 'title' => 'Default', 'price' => 10 },
+          'product' => product_drop.new,
+        },
+      )
+    end
+
     def test_render_captured_snippet
       template = <<~LIQUID
         {% assign color_scheme = 'dark' %}
@@ -1063,6 +1211,132 @@ class SnippetTest < Minitest::Test
       assert_template_result(expected, template, error_mode: :rigid)
     end
 
+    def test_render_inline_snippet_with_spread_drop
+      product_drop = Class.new(Liquid::Drop) do
+        def title
+          'Cool Product'
+        end
+
+        def price
+          99
+        end
+
+        def vendor
+          'Acme'
+        end
+      end
+
+      template = <<~LIQUID.strip
+        {% snippet card %}
+        <div>
+          {{ title }} - ${{ price }} by {{ vendor }}
+        </div>
+        {% endsnippet %}
+
+        {% render card, ...product %}
+      LIQUID
+
+      expected = <<~OUTPUT
+
+
+
+        <div>
+          Cool Product - $99 by Acme
+        </div>
+      OUTPUT
+
+      assert_template_result(expected, template, { 'product' => product_drop.new }, error_mode: :rigid)
+    end
+
+    def test_render_inline_snippet_with_overwritten_spread_drop
+      product_drop = Class.new(Liquid::Drop) do
+        def title
+          'Cool Product'
+        end
+
+        def price
+          99
+        end
+
+        def vendor
+          'Acme'
+        end
+      end
+
+      template = <<~LIQUID.strip
+        {% snippet card %}
+        <div>
+          {{ title }} - ${{ price }} by {{ vendor }}
+        </div>
+        {% endsnippet %}
+
+        {% render card, ...product, price: 10 %}
+      LIQUID
+
+      expected = <<~OUTPUT
+
+
+
+        <div>
+          Cool Product - $10 by Acme
+        </div>
+      OUTPUT
+
+      assert_template_result(expected, template, { 'product' => product_drop.new }, error_mode: :rigid)
+    end
+
+    def test_render_inline_snippet_spread_before_explicit_args
+      template = <<~LIQUID.strip
+        {% snippet card %}
+        <div>{{ price }}</div>
+        {% endsnippet %}
+
+        {% render card, ...details, price: 10 %}
+      LIQUID
+
+      expected = <<~OUTPUT
+
+
+
+        <div>10</div>
+      OUTPUT
+
+      assert_template_result(expected, template, { 'details' => { 'price' => 99 } }, error_mode: :rigid)
+    end
+
+    def test_render_inline_snippet_multiple_spreads
+      product_drop = Class.new(Liquid::Drop) do
+        def title
+          'Cool Product'
+        end
+      end
+
+      template = <<~LIQUID.strip
+        {% snippet card %}
+        <div>{{ title }} - {{ price }} {{ color }}</div>
+        {% endsnippet %}
+
+        {% render card, ...defaults, ...product %}
+      LIQUID
+
+      expected = <<~OUTPUT
+
+
+
+        <div>Cool Product - 10 </div>
+      OUTPUT
+
+      assert_template_result(
+        expected,
+        template,
+        {
+          'defaults' => { 'title' => 'Default', 'price' => 10 },
+          'product' => product_drop.new,
+        },
+        error_mode: :rigid,
+      )
+    end
+
     def test_render_captured_snippet
       template = <<~LIQUID
         {% assign color_scheme = 'dark' %}