assert_template: validating option keys

actionpack/CHANGELOG.md

 ## Rails 4.0.0 (unreleased) ##
 
-*   `assert_template` is no more passing with empty string.
+*   `assert_template`:
+    - is no more passing with empty string.
+    - is now validating option keys. It accepts: `:layout`, `:partial`, `:locals` and `:count`.
 
     *Roberto Soares*
 

actionpack/lib/action_controller/test_case.rb

@@ -106,6 +106,8 @@ def assert_template(options = {}, message = nil)
           end
         assert matches_template, msg
       when Hash
+        options.assert_valid_keys(:layout, :partial, :locals, :count)
+
         if options.key?(:layout)
           expected_layout = options[:layout]
           msg = message || sprintf("expecting layout <%s> but action rendered <%s>",

actionpack/test/controller/action_pack_assertions_test.rb

@@ -430,6 +430,12 @@ def test_assert_response_failure_response_with_no_exception
 class AssertTemplateTest < ActionController::TestCase
   tests ActionPackAssertionsController
 
+  def test_with_invalid_hash_keys_raises_argument_error
+    assert_raise(ArgumentError) do
+      assert_template foo: "bar"
+    end
+  end
+
   def test_with_partial
     get :partial
     assert_template :partial => '_partial'