Merge pull request #349 from Shopify/render_bang_allow_not_safe_contexts

render! will properly force rethrow of errors if context is passed as an argument

.travis.yml

@@ -1,7 +1,8 @@
 rvm:
   - 1.9.3
   - 2.0.0
-  - 2.1.0
+  - 2.1
+  - 2.1.1
   - jruby-19mode
   - jruby-head
   - rbx-19mode

History.md

@@ -3,6 +3,7 @@
 ## 3.0.0 / not yet released / branch "master"
 
 * ...
+* Properly set context rethrow_errors on render! #349 [Thierry Joyal, tjoyal]
 * Fix broken rendering of variables which are equal to false, see #345 [Florian Weingarten, fw42]
 * Remove ActionView template handler [Dylan Thacker-Smith, dylanahsmith]
 * Freeze lots of string literals for new Ruby 2.1 optimization, see #297 [Florian Weingarten, fw42]

lib/liquid/context.rb

@@ -15,6 +15,8 @@ module Liquid
   class Context
     attr_reader :scopes, :errors, :registers, :environments, :resource_limits
 
+    attr_accessor :rethrow_errors
+
     def initialize(environments = {}, outer_scope = {}, registers = {}, rethrow_errors = false, resource_limits = {})
       @environments    = [environments].flatten
       @scopes          = [(outer_scope || {})]

lib/liquid/template.rb

@@ -113,7 +113,9 @@ module Liquid
 
       context = case args.first
       when Liquid::Context
-        args.shift
+        c = args.shift
+        c.rethrow_errors = true if @rethrow_errors
+        c
       when Liquid::Drop
         drop = args.shift
         drop.context = Context.new([drop, assigns], instance_assigns, registers, @rethrow_errors, @resource_limits)
@@ -156,7 +158,8 @@ module Liquid
     end
 
     def render!(*args)
-      @rethrow_errors = true; render(*args)
+      @rethrow_errors = true
+      render(*args)
     end
 
     private

test/integration/template_test.rb

@@ -22,6 +22,12 @@ class SomethingWithLength
   liquid_methods :length
 end
 
+class ErroneousDrop < Liquid::Drop
+  def bad_method
+    raise 'ruby error in drop'
+  end
+end
+
 class TemplateTest < Test::Unit::TestCase
   include Liquid
 
@@ -137,4 +143,14 @@ class TemplateTest < Test::Unit::TestCase
     assert_equal 'bar', t.parse('{{bar}}').render!(drop)
     assert_equal 'haha', t.parse("{{baz}}").render!(drop)
   end
+
+  def test_render_bang_force_rethrow_errors_on_passed_context
+    context = Context.new({'drop' => ErroneousDrop.new})
+    t = Template.new.parse('{{ drop.bad_method }}')
+
+    e = assert_raises RuntimeError do
+      t.render!(context)
+    end
+    assert_equal 'ruby error in drop', e.message
+  end
 end