Fixed #15838 -- Promoted assertFieldOutput to a general test utility. Thanks to Ramiro Morales for the patch.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@16653 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/test/testcases.py

@@ -8,11 +8,14 @@ from xml.dom.minidom import parseString, Node
 
 from django.conf import settings
 from django.core import mail
+from django.core.exceptions import ValidationError
 from django.core.management import call_command
 from django.core.signals import request_started
 from django.core.urlresolvers import clear_url_caches
+from django.core.validators import EMPTY_VALUES
 from django.db import (transaction, connection, connections, DEFAULT_DB_ALIAS,
     reset_queries)
+from django.forms.fields import CharField
 from django.http import QueryDict
 from django.test import _doctest as doctest
 from django.test.client import Client
@@ -271,6 +274,53 @@ class SimpleTestCase(ut2.TestCase):
         return self.assertRaisesRegexp(expected_exception,
                 re.escape(expected_message), callable_obj, *args, **kwargs)
 
+    def assertFieldOutput(self, fieldclass, valid, invalid, field_args=None,
+            field_kwargs=None, empty_value=u''):
+        """
+        Asserts that a form field behaves correctly with various inputs.
+
+        Args:
+            fieldclass: the class of the field to be tested.
+            valid: a dictionary mapping valid inputs to their expected
+                    cleaned values.
+            invalid: a dictionary mapping invalid inputs to one or more
+                    raised error messages.
+            field_args: the args passed to instantiate the field
+            field_kwargs: the kwargs passed to instantiate the field
+            empty_value: the expected clean output for inputs in EMPTY_VALUES
+
+        """
+        if field_args is None:
+            field_args = []
+        if field_kwargs is None:
+            field_kwargs = {}
+        required = fieldclass(*field_args, **field_kwargs)
+        optional = fieldclass(*field_args, **dict(field_kwargs, required=False))
+        # test valid inputs
+        for input, output in valid.items():
+            self.assertEqual(required.clean(input), output)
+            self.assertEqual(optional.clean(input), output)
+        # test invalid inputs
+        for input, errors in invalid.items():
+            with self.assertRaises(ValidationError) as context_manager:
+                required.clean(input)
+            self.assertEqual(context_manager.exception.messages, errors)
+
+            with self.assertRaises(ValidationError) as context_manager:
+                optional.clean(input)
+            self.assertEqual(context_manager.exception.messages, errors)
+        # test required inputs
+        error_required = [u'This field is required.']
+        for e in EMPTY_VALUES:
+            with self.assertRaises(ValidationError) as context_manager:
+                required.clean(e)
+            self.assertEqual(context_manager.exception.messages, error_required)
+            self.assertEqual(optional.clean(e), empty_value)
+        # test that max_length and min_length are always accepted
+        if issubclass(fieldclass, CharField):
+            field_kwargs.update({'min_length':2, 'max_length':20})
+            self.assertTrue(isinstance(fieldclass(*field_args, **field_kwargs), fieldclass))
+
 class TransactionTestCase(SimpleTestCase):
     # The class we'll use for the test client self.client.
     # Can be overridden in derived classes.
@@ -356,8 +406,8 @@ class TransactionTestCase(SimpleTestCase):
         # be created with the wrong time).
         # To make sure this doesn't happen, get a clean connection at the
         # start of every test.
-        for connection in connections.all():
-            connection.close()
+        for conn in connections.all():
+            conn.close()
 
     def _fixture_teardown(self):
         pass
@@ -552,9 +602,9 @@ class TransactionTestCase(SimpleTestCase):
 
     def assertNumQueries(self, num, func=None, *args, **kwargs):
         using = kwargs.pop("using", DEFAULT_DB_ALIAS)
-        connection = connections[using]
+        conn = connections[using]
 
-        context = _AssertNumQueriesContext(self, num, connection)
+        context = _AssertNumQueriesContext(self, num, conn)
         if func is None:
             return context