Fixed #24476 -- Added context manager/decorator for overriding script prefix.

Tests were using an undocumented keyword argument for easily overriding
script prefix while reversing. This is now changed into a test utility
which can be used as decorator or context manager.

6 files changed, 54 insertions, 45 deletions

diff --git a/django/core/urlresolvers.py b/django/core/urlresolvers.py
index cf42768add..563d4a7ade 100644
--- a/django/core/urlresolvers.py
+++ b/django/core/urlresolvers.py
@@ -527,15 +527,14 @@ def resolve(path, urlconf=None):
     return get_resolver(urlconf).resolve(path)
 
 
-def reverse(viewname, urlconf=None, args=None, kwargs=None, prefix=None, current_app=None):
+def reverse(viewname, urlconf=None, args=None, kwargs=None, current_app=None):
     if urlconf is None:
         urlconf = get_urlconf()
     resolver = get_resolver(urlconf)
     args = args or []
     kwargs = kwargs or {}
 
-    if prefix is None:
-        prefix = get_script_prefix()
+    prefix = get_script_prefix()
 
     if not isinstance(viewname, six.string_types):
         view = viewname
diff --git a/django/test/utils.py b/django/test/utils.py
index 5224bcfb71..0101919d11 100644
--- a/django/test/utils.py
+++ b/django/test/utils.py
@@ -12,11 +12,13 @@ from django.apps import apps
 from django.conf import UserSettingsHolder, settings
 from django.core import mail
 from django.core.signals import request_started
+from django.core.urlresolvers import get_script_prefix, set_script_prefix
 from django.db import reset_queries
 from django.http import request
 from django.template import Template
 from django.test.signals import setting_changed, template_rendered
 from django.utils import six
+from django.utils.decorators import ContextDecorator
 from django.utils.encoding import force_str
 from django.utils.translation import deactivate
 
@@ -595,3 +597,22 @@ def require_jinja2(test_func):
         'OPTIONS': {'keep_trailing_newline': True},
     }])(test_func)
     return test_func
+
+
+class ScriptPrefix(ContextDecorator):
+    def __enter__(self):
+        set_script_prefix(self.prefix)
+
+    def __exit__(self, exc_type, exc_val, traceback):
+        set_script_prefix(self.old_prefix)
+
+    def __init__(self, prefix):
+        self.prefix = prefix
+        self.old_prefix = get_script_prefix()
+
+
+def override_script_prefix(prefix):
+    """
+    Decorator or context manager to temporary override the script prefix.
+    """
+    return ScriptPrefix(prefix)
diff --git a/tests/admin_views/tests.py b/tests/admin_views/tests.py
index 44490f7a7d..429f9d7b6c 100644
--- a/tests/admin_views/tests.py
+++ b/tests/admin_views/tests.py
@@ -22,15 +22,13 @@ from django.contrib.staticfiles.storage import staticfiles_storage
 from django.core import mail
 from django.core.checks import Error
 from django.core.files import temp as tempfile
-from django.core.urlresolvers import (
-    NoReverseMatch, get_script_prefix, resolve, reverse, set_script_prefix,
-)
+from django.core.urlresolvers import NoReverseMatch, resolve, reverse
 from django.forms.utils import ErrorList
 from django.template.response import TemplateResponse
 from django.test import (
     TestCase, modify_settings, override_settings, skipUnlessDBFeature,
 )
-from django.test.utils import patch_logger
+from django.test.utils import override_script_prefix, patch_logger
 from django.utils import formats, six, translation
 from django.utils._os import upath
 from django.utils.cache import get_max_age
@@ -5822,16 +5820,12 @@ class AdminKeepChangeListFiltersTests(TestCase):
             add_preserved_filters(context, url),
         )
 
-        original_prefix = get_script_prefix()
-        try:
-            set_script_prefix('/prefix/')
+        with override_script_prefix('/prefix/'):
             url = reverse('admin:auth_user_changelist', current_app=self.admin_site.name)
             self.assertURLEqual(
                 self.get_changelist_url(),
                 add_preserved_filters(context, url),
             )
-        finally:
-            set_script_prefix(original_prefix)
 
 
 class NamespacedAdminKeepChangeListFiltersTests(AdminKeepChangeListFiltersTests):
diff --git a/tests/flatpages_tests/test_models.py b/tests/flatpages_tests/test_models.py
index c48dc38637..8c67450f40 100644
--- a/tests/flatpages_tests/test_models.py
+++ b/tests/flatpages_tests/test_models.py
@@ -3,8 +3,8 @@
 from __future__ import unicode_literals
 
 from django.contrib.flatpages.models import FlatPage
-from django.core.urlresolvers import clear_script_prefix, set_script_prefix
 from django.test import TestCase
+from django.test.utils import override_script_prefix
 
 
 class FlatpageModelTests(TestCase):
@@ -13,10 +13,7 @@ class FlatpageModelTests(TestCase):
         pf = FlatPage(title="Café!", url='/café/')
         self.assertEqual(pf.get_absolute_url(), '/caf%C3%A9/')
 
+    @override_script_prefix('/beverages/')
     def test_get_absolute_url_honors_script_prefix(self):
         pf = FlatPage(title="Tea!", url='/tea/')
-        set_script_prefix('/beverages/')
-        try:
-            self.assertEqual(pf.get_absolute_url(), '/beverages/tea/')
-        finally:
-            clear_script_prefix()
+        self.assertEqual(pf.get_absolute_url(), '/beverages/tea/')
diff --git a/tests/i18n/patterns/tests.py b/tests/i18n/patterns/tests.py
index 62ca49b67d..07a01f6d9b 100644
--- a/tests/i18n/patterns/tests.py
+++ b/tests/i18n/patterns/tests.py
@@ -3,13 +3,12 @@ from __future__ import unicode_literals
 import os
 
 from django.core.exceptions import ImproperlyConfigured
-from django.core.urlresolvers import (
-    clear_url_caches, reverse, set_script_prefix, translate_url,
-)
+from django.core.urlresolvers import clear_url_caches, reverse, translate_url
 from django.http import HttpResponsePermanentRedirect
 from django.middleware.locale import LocaleMiddleware
 from django.template import Context, Template
 from django.test import TestCase, override_settings
+from django.test.utils import override_script_prefix
 from django.utils import translation
 from django.utils._os import upath
 
@@ -314,19 +313,11 @@ class URLRedirectWithScriptAliasTests(URLTestCaseBase):
     """
     #21579 - LocaleMiddleware should respect the script prefix.
     """
-    def setUp(self):
-        super(URLRedirectWithScriptAliasTests, self).setUp()
-        self.script_prefix = '/script_prefix'
-        set_script_prefix(self.script_prefix)
-
-    def tearDown(self):
-        super(URLRedirectWithScriptAliasTests, self).tearDown()
-        # reset script prefix
-        set_script_prefix('')
-
     def test_language_prefix_with_script_prefix(self):
-        response = self.client.get('/prefixed/', HTTP_ACCEPT_LANGUAGE='en', SCRIPT_NAME=self.script_prefix)
-        self.assertRedirects(response, '%s/en/prefixed/' % self.script_prefix, target_status_code=404)
+        prefix = '/script_prefix'
+        with override_script_prefix(prefix):
+            response = self.client.get('/prefixed/', HTTP_ACCEPT_LANGUAGE='en', SCRIPT_NAME=prefix)
+            self.assertRedirects(response, '%s/en/prefixed/' % prefix, target_status_code=404)
 
 
 class URLTagTests(URLTestCaseBase):
diff --git a/tests/urlpatterns_reverse/tests.py b/tests/urlpatterns_reverse/tests.py
index 28f4ff4d0b..4e2fcd3a31 100644
--- a/tests/urlpatterns_reverse/tests.py
+++ b/tests/urlpatterns_reverse/tests.py
@@ -24,6 +24,7 @@ from django.shortcuts import redirect
 from django.test import (
     SimpleTestCase, TestCase, ignore_warnings, override_settings,
 )
+from django.test.utils import override_script_prefix
 from django.utils import six
 from django.utils.deprecation import RemovedInDjango20Warning
 
@@ -199,33 +200,38 @@ class URLPatternReverse(TestCase):
         # Reversing None should raise an error, not return the last un-named view.
         self.assertRaises(NoReverseMatch, reverse, None)
 
+    @override_script_prefix('/{{invalid}}/')
     def test_prefix_braces(self):
         self.assertEqual(
             '/%7B%7Binvalid%7D%7D/includes/non_path_include/',
-            reverse('non_path_include', prefix='/{{invalid}}/')
+            reverse('non_path_include')
         )
 
     def test_prefix_parenthesis(self):
         # Parentheses are allowed and should not cause errors or be escaped
-        self.assertEqual(
-            '/bogus)/includes/non_path_include/',
-            reverse('non_path_include', prefix='/bogus)/')
-        )
-        self.assertEqual(
-            '/(bogus)/includes/non_path_include/',
-            reverse('non_path_include', prefix='/(bogus)/')
-        )
+        with override_script_prefix('/bogus)/'):
+            self.assertEqual(
+                '/bogus)/includes/non_path_include/',
+                reverse('non_path_include')
+            )
+        with override_script_prefix('/(bogus)/'):
+            self.assertEqual(
+                '/(bogus)/includes/non_path_include/',
+                reverse('non_path_include')
+            )
 
+    @override_script_prefix('/bump%20map/')
     def test_prefix_format_char(self):
         self.assertEqual(
             '/bump%2520map/includes/non_path_include/',
-            reverse('non_path_include', prefix='/bump%20map/')
+            reverse('non_path_include')
         )
 
+    @override_script_prefix('/%7Eme/')
     def test_non_urlsafe_prefix_with_args(self):
         # Regression for #20022, adjusted for #24013 because ~ is an unreserved
         # character. Tests whether % is escaped.
-        self.assertEqual('/%257Eme/places/1/', reverse('places', args=[1], prefix='/%7Eme/'))
+        self.assertEqual('/%257Eme/places/1/', reverse('places', args=[1]))
 
     def test_patterns_reported(self):
         # Regression for #17076
@@ -240,9 +246,10 @@ class URLPatternReverse(TestCase):
             # exception
             self.fail("Expected a NoReverseMatch, but none occurred.")
 
+    @override_script_prefix('/script:name/')
     def test_script_name_escaping(self):
         self.assertEqual(
-            reverse('optional', args=['foo:bar'], prefix='/script:name/'),
+            reverse('optional', args=['foo:bar']),
             '/script:name/optional/foo:bar/'
         )