Templates and Contexts differentiate between different sources of assigns

test/template_test.rb

@@ -23,4 +23,35 @@ class TemplateTest < Test::Unit::TestCase
     assert_equal ['  ', '{% comment %}', ' ', '{% endcomment %}', ' '], Template.new.send(:tokenize, "  {% comment %} {% endcomment %} ")    
   end                                                          
   
+  def test_instance_assigns_persist_on_same_template_object_between_parses
+    t = Template.new
+    assert_equal 'from instance assigns', t.parse("{% assign foo = 'from instance assigns' %}{{ foo }}").render
+    assert_equal 'from instance assigns', t.parse("{{ foo }}").render
+  end
+  
+  def test_instance_assigns_persist_on_same_template_parsing_between_renders
+    t = Template.new.parse("{{ foo }}{% assign foo = 'foo' %}{{ foo }}")
+    assert_equal 'foo', t.render
+    assert_equal 'foofoo', t.render
+  end
+  
+  def test_custom_assigns_do_not_persist_on_same_template
+    t = Template.new
+    assert_equal 'from custom assigns', t.parse("{{ foo }}").render('foo' => 'from custom assigns')
+    assert_equal '', t.parse("{{ foo }}").render
+  end
+  
+  def test_custom_assigns_squash_instance_assigns
+    t = Template.new
+    assert_equal 'from instance assigns', t.parse("{% assign foo = 'from instance assigns' %}{{ foo }}").render
+    assert_equal 'from custom assigns', t.parse("{{ foo }}").render('foo' => 'from custom assigns')
+  end
+  
+  def test_persistent_assigns_squash_instance_assigns
+    t = Template.new
+    assert_equal 'from instance assigns', t.parse("{% assign foo = 'from instance assigns' %}{{ foo }}").render
+    t.assigns['foo'] = 'from persistent assigns'
+    assert_equal 'from persistent assigns', t.parse("{{ foo }}").render
+  end
+  
 end