From 3784020a8d087f6330580a74d72367c1ef96eb59 Mon Sep 17 00:00:00 2001
From: Mike Angell <53470248+shopmike@users.noreply.github.com>
Date: Thu, 17 Oct 2019 23:06:13 +1000
Subject: [PATCH] [New Feature] Add forloop inside render tag when using for
 syntax (#1191)

* Add forloop to render for syntax

* Remove forloop guard
---
 lib/liquid/tags/render.rb                | 11 +++++++++--
 test/integration/tags/render_tag_test.rb |  9 +++++++++
 2 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/lib/liquid/tags/render.rb b/lib/liquid/tags/render.rb
index c322247..73773ee 100644
--- a/lib/liquid/tags/render.rb
+++ b/lib/liquid/tags/render.rb
@@ -43,19 +43,26 @@ module Liquid
 
       context_variable_name = @alias_name || template_name.split('/').last
 
-      render_partial_func = ->(var) {
+      render_partial_func = ->(var, forloop) {
         inner_context = context.new_isolated_subcontext
         inner_context.template_name = template_name
         inner_context.partial = true
+        inner_context['forloop'] = forloop if forloop
         @attributes.each do |key, value|
           inner_context[key] = context.evaluate(value)
         end
         inner_context[context_variable_name] = var unless var.nil?
         partial.render_to_output_buffer(inner_context, output)
+        forloop&.send(:increment!)
       }
 
       variable = @variable_name_expr ? context.evaluate(@variable_name_expr) : nil
-      variable.is_a?(Array) ? variable.each(&render_partial_func) : render_partial_func.call(variable)
+      if variable.is_a?(Array)
+        forloop = Liquid::ForloopDrop.new(template_name, variable.count, nil)
+        variable.each { |var| render_partial_func.call(var, forloop) }
+      else
+        render_partial_func.call(variable, nil)
+      end
 
       output
     end
diff --git a/test/integration/tags/render_tag_test.rb b/test/integration/tags/render_tag_test.rb
index f2fbc55..f2940c3 100644
--- a/test/integration/tags/render_tag_test.rb
+++ b/test/integration/tags/render_tag_test.rb
@@ -205,4 +205,13 @@ class RenderTagTest < Minitest::Test
     assert_template_result("Product: Draft 151cm Product: Element 155cm ",
                            "{% render 'product' for products %}", "products" => [{ 'title' => 'Draft 151cm' }, { 'title' => 'Element 155cm' }])
   end
+
+  def test_render_tag_forloop
+    Liquid::Template.file_system = StubFileSystem.new(
+      'product' => "Product: {{ product.title }} {% if forloop.first %}first{% endif %} {% if forloop.last %}last{% endif %} index:{{ forloop.index }} ",
+    )
+
+    assert_template_result("Product: Draft 151cm first  index:1 Product: Element 155cm  last index:2 ",
+                           "{% render 'product' for products %}", "products" => [{ 'title' => 'Draft 151cm' }, { 'title' => 'Element 155cm' }])
+  end
 end