From 9075b428b143827c467e33fec2816423b1265b88 Mon Sep 17 00:00:00 2001
From: Florian Weingarten <flo@shopify.com>
Date: Fri, 31 May 2013 09:25:25 -0400
Subject: [PATCH] Resource limits: Don't raise Error but render error message
 (but abort after first error)

---
 lib/liquid/block.rb          |  4 ++--
 lib/liquid/template.rb       |  4 +++-
 test/liquid/template_test.rb | 21 +++++++++++++++++----
 3 files changed, 22 insertions(+), 7 deletions(-)

diff --git a/lib/liquid/block.rb b/lib/liquid/block.rb
index 9f888811..efd149be 100644
--- a/lib/liquid/block.rb
+++ b/lib/liquid/block.rb
@@ -108,9 +108,9 @@ module Liquid
 
           token_output = (token.respond_to?(:render) ? token.render(context) : token)
           context.resource_limits[:render_length_current] += (token_output.respond_to?(:length) ? token_output.length : 1)
-          raise Liquid::MemoryError, context.resource_limits if context.resource_limits_reached?
+          raise MemoryError.new("Memory limits exceeded") if context.resource_limits_reached?
           output << token_output
-        rescue Liquid::MemoryError => e
+        rescue MemoryError => e
           raise e
         rescue ::StandardError => e
           output << (context.handle_error(e))
diff --git a/lib/liquid/template.rb b/lib/liquid/template.rb
index 43c9318a..10a78049 100644
--- a/lib/liquid/template.rb
+++ b/lib/liquid/template.rb
@@ -120,9 +120,11 @@ module Liquid
 
       begin
         # render the nodelist.
-        # for performance reasons we get a array back here. join will make a string out of it
+        # for performance reasons we get an array back here. join will make a string out of it.
         result = @root.render(context)
         result.respond_to?(:join) ? result.join : result
+      rescue Liquid::MemoryError => e
+        context.handle_error(e)
       ensure
         @errors = context.errors
       end
diff --git a/test/liquid/template_test.rb b/test/liquid/template_test.rb
index 4e912c98..bc1c9a32 100644
--- a/test/liquid/template_test.rb
+++ b/test/liquid/template_test.rb
@@ -72,26 +72,39 @@ class TemplateTest < Test::Unit::TestCase
     @global = nil
   end
 
-  def test_resource_limits
+  def test_resource_limits_render_length
     t = Template.parse("0123456789")
     t.resource_limits = { :render_length_limit => 5 }
-    assert_raises(Liquid::MemoryError) { t.render() }
+    assert_equal "Liquid error: Memory limits exceeded", t.render()
     t.resource_limits = { :render_length_limit => 10 }
     assert_equal "0123456789", t.render()
     assert_not_nil t.resource_limits[:render_length_current]
+  end
 
+  def test_resource_limits_render_score
+    t = Template.parse("{% for a in (1..10) %} {% for a in (1..10) %} foo {% endfor %} {% endfor %}")
+    t.resource_limits = { :render_score_limit => 50 }
+    assert_equal "Liquid error: Memory limits exceeded", t.render()
     t = Template.parse("{% for a in (1..100) %} foo {% endfor %}")
     t.resource_limits = { :render_score_limit => 50 }
-    assert_raises(Liquid::MemoryError) { t.render() }
+    assert_equal "Liquid error: Memory limits exceeded", t.render()
     t.resource_limits = { :render_score_limit => 200 }
     assert_equal (" foo " * 100), t.render()
     assert_not_nil t.resource_limits[:render_score_current]
+  end
 
+  def test_resource_limits_assign_score
     t = Template.parse("{% assign foo = 42 %}{% assign bar = 23 %}")
     t.resource_limits = { :assign_score_limit => 1 }
-    assert_raises(Liquid::MemoryError) { t.render() }
+    assert_equal "Liquid error: Memory limits exceeded", t.render()
     t.resource_limits = { :assign_score_limit => 2 }
     assert_equal "", t.render()
     assert_not_nil t.resource_limits[:assign_score_current]
   end
+
+  def test_resource_limits_aborts_rendering_after_first_error
+    t = Template.parse("{% for a in (1..100) %} foo1 {% endfor %} bar {% for a in (1..100) %} foo2 {% endfor %}")
+    t.resource_limits = { :render_score_limit => 50 }
+    assert_equal "Liquid error: Memory limits exceeded", t.render()
+  end
 end # TemplateTest