Don't show edit/create page buttons and page git changes when user doesn't have required permissions

[fpytloun]

Don't know if this is desired behavior but it makes sense to me to don't show
per-page button if user doesn't have permissions to edit given page.
Therefore it also makes sense to raise 404 when user access page that doesn't
exist and doesn't have permissions to create it (eg. anonymous user).

Fixing behavior of whatchanged makes it possible to have part of wiki hidden and available only for given users/groups.

[fpytloun]

Hm, I am not sure how to fix the tests. Tried following:

diff --git a/tests/test_views.py b/tests/test_views.py
index 649d366..0dfddbd 100644
--- a/tests/test_views.py
+++ b/tests/test_views.py
@@ -22,8 +22,8 @@ class TestPageView(TestCase):
         response = self.client.get(self.page.get_absolute_url())
         self.assertContains(response, self.page.title)
         self.assertContains(response, self.page.body)
+        # We don't have edit permissions, there should be no edit link
         self.assertContains(response, self.edit_url)
-        self.assertTemplateUsed(response, 'waliki/detail.html')

     def test_view_raw(self):
         response = self.client.get(self.page.get_absolute_url() + '/raw')
@@ -37,9 +37,10 @@ class TestPageView(TestCase):

     def test_view_auth(self):
         user = UserFactory()
+        ACLRuleFactory(slug=self.page.slug, permissions=['change_page'], users=[user])
         self.client.login(username=user.username, password='pass')
-        with mock.patch('waliki.acl.WALIKI_ANONYMOUS_USER_PERMISSIONS', return_value=()):
-            response = self.client.get(self.page.get_absolute_url())
+
+        response = self.client.get(self.page.get_absolute_url())
         self.assertContains(response, self.page.body)
         self.assertContains(response, self.edit_url)
         self.assertTemplateUsed(response, 'waliki/detail.html')

But test_view_auth still doesn't work. It seems that permissions were not applied correctly before self.client.get