Added test case for format_suffix_patterns to validate changes introduced with issue #593.

Signed-off-by: Kevin Stone <kevinastone@gmail.com>

rest_framework/tests/urlpatterns.py

+from collections import namedtuple
+
+from django.core import urlresolvers
+
+from django.test import TestCase
+from django.test.client import RequestFactory
+
+from rest_framework.compat import patterns, url, include
+from rest_framework.urlpatterns import format_suffix_patterns
+
+
+# A container class for test paths for the test case
+URLTestPath = namedtuple('URLTestPath', ['path', 'args', 'kwargs'])
+
+
+def test_view(request, *args, **kwargs):
+    pass
+
+
+class FormatSuffixTests(TestCase):
+    def _test_urlpatterns(self, urlpatterns, test_paths):
+        factory = RequestFactory()
+        try:
+            urlpatterns = format_suffix_patterns(urlpatterns)
+        except:
+            self.fail("Failed to apply `format_suffix_patterns` on  the supplied urlpatterns")
+        resolver = urlresolvers.RegexURLResolver(r'^/', urlpatterns)
+        for test_path in test_paths:
+            request = factory.get(test_path.path)
+            try:
+                callback, callback_args, callback_kwargs = resolver.resolve(request.path_info)
+            except:
+                self.fail("Failed to resolve URL: %s" % request.path_info)
+            self.assertEquals(callback_args, test_path.args)
+            self.assertEquals(callback_kwargs, test_path.kwargs)
+
+    def test_format_suffix(self):
+        urlpatterns = patterns(
+            '',
+            url(r'^test$', test_view),
+        )
+        test_paths = [
+            URLTestPath('/test', (), {}),
+            URLTestPath('/test.api', (), {'format': 'api'}),
+            URLTestPath('/test.asdf', (), {'format': 'asdf'}),
+        ]
+        self._test_urlpatterns(urlpatterns, test_paths)
+
+    def test_default_args(self):
+        urlpatterns = patterns(
+            '',
+            url(r'^test$', test_view, {'foo': 'bar'}),
+        )
+        test_paths = [
+            URLTestPath('/test', (), {'foo': 'bar', }),
+            URLTestPath('/test.api', (), {'foo': 'bar', 'format': 'api'}),
+            URLTestPath('/test.asdf', (), {'foo': 'bar', 'format': 'asdf'}),
+        ]
+        self._test_urlpatterns(urlpatterns, test_paths)
+
+    def test_included_urls(self):
+        nested_patterns = patterns(
+            '',
+            url(r'^path$', test_view)
+        )
+        urlpatterns = patterns(
+            '',
+            url(r'^test/', include(nested_patterns), {'foo': 'bar'}),
+        )
+        test_paths = [
+            URLTestPath('/test/path', (), {'foo': 'bar', }),
+            URLTestPath('/test/path.api', (), {'foo': 'bar', 'format': 'api'}),
+            URLTestPath('/test/path.asdf', (), {'foo': 'bar', 'format': 'asdf'}),
+        ]
+        self._test_urlpatterns(urlpatterns, test_paths)