assert_template matches against Regexp

This allows for more strict template assertions,
while maintaining backward compatibility.

For example, if you use assert_template("foo/bar")
and "foo/bar/baz" was rendered, the test passes.

But if you use assert_template(%r{\Afoo/bar\Z}),
you will catch that a different template was
rendered.

Also, if you passed an unsupported argument to
assert_template() in the past, it would silently
succeed. Now it raises an ArgumentError.

1 files changed, 7 insertions, 2 deletions

diff --git a/actionpack/lib/action_controller/test_case.rb b/actionpack/lib/action_controller/test_case.rb
index e9a3ec5a22..7af30ed690 100644
--- a/actionpack/lib/action_controller/test_case.rb
+++ b/actionpack/lib/action_controller/test_case.rb
@@ -56,6 +56,9 @@ module ActionController
     #   # assert that the "new" view template was rendered
     #   assert_template "new"
     #
+    #   # assert that the exact template "admin/posts/new" was rendered
+    #   assert_template %r{\Aadmin/posts/new\Z}
+    #
     #   # assert that the "_customer" partial was rendered twice
     #   assert_template :partial => '_customer', :count => 2
     #
@@ -74,11 +77,11 @@ module ActionController
       response.body
 
       case options
-      when NilClass, String, Symbol
+      when NilClass, String, Symbol, Regexp
         options = options.to_s if Symbol === options
         rendered = @templates
         msg = message || sprintf("expecting <%s> but rendering with <%s>",
-                options, rendered.keys)
+                options.inspect, rendered.keys)
         assert_block(msg) do
           if options
             rendered.any? { |t,num| t.match(options) }
@@ -121,6 +124,8 @@ module ActionController
           assert @partials.empty?,
             "Expected no partials to be rendered"
         end
+      else
+        raise ArgumentError, "assert_template only accepts a String, Symbol, Hash, Regexp, or nil"
       end
     end
   end