Proper warning support

Rakefile

@@ -14,6 +14,12 @@ Rake::TestTask.new(:base_test) do |t|
   t.verbose = false
 end
 
+desc 'run test suite with warn error mode'
+task :warn_test do
+  ENV['LIQUID_PARSER_MODE'] = 'warn'
+  Rake::Task['base_test'].invoke
+end
+
 desc 'runs test suite with both strict and lax parsers'
 task :test do
   ENV['LIQUID_PARSER_MODE'] = 'lax'

lib/liquid/tags/for.rb

@@ -58,6 +58,7 @@ module Liquid
     end
 
     def render(context)
+      context.errors.concat(@warnings) if @warnings
       context.registers[:for] ||= Hash.new(0)
 
       collection = context[@collection_name]

lib/liquid/tags/if.rb

@@ -29,7 +29,7 @@ module Liquid
     end
 
     def render(context)
-      context.errors += @warnings if @warnings
+      context.errors.concat(@warnings) if @warnings
       context.stack do
         @blocks.each do |block|
           if block.evaluate(context)

test/liquid/error_handling_test.rb

@@ -79,6 +79,13 @@ class ErrorHandlingTest < Test::Unit::TestCase
     end
   end
 
+  def test_warnings
+    template = Liquid::Template.parse('{% if ~~~ %}derp{% else %}wat{% endif %}', :error_mode => :warn)
+    assert_equal 'wat', template.render
+    assert_equal 1, template.errors.size
+    assert_equal 'Unexpected character ~.', template.errors.first.message
+  end
+
   # Liquid should not catch Exceptions that are not subclasses of StandardError, like Interrupt and NoMemoryError
   def test_exceptions_propagate
     assert_raise Exception do