feat(django 1.9): Replaced validation for whitespace-only title fields

Django now strips whitespace automatically making Wagtail's whitespace check obsolete.

This commit removes our old checks and replicates Django's new behaviour for users of 1.8 and below.

wagtail/wagtailadmin/tests/test_pages_views.py

@@ -1,6 +1,7 @@
 from datetime import timedelta
 import mock
 
+import django
 from django.test import TestCase
 from django.core.urlresolvers import reverse
 from django.contrib.auth import get_user_model
@@ -626,15 +627,48 @@ class TestPageCreation(TestCase, WagtailTestUtils):
             'content': "Some content",
             'slug': 'hello-world',
             'action-submit': "Submit",
-            'seo_title': '\t',
         }
         response = self.client.post(
             reverse('wagtailadmin_pages:add', args=('tests', 'simplepage', self.root_page.id)), post_data
         )
 
         # Check that a form error was raised
-        self.assertFormError(response, 'form', 'title', "Value cannot be entirely whitespace characters")
-        self.assertFormError(response, 'form', 'seo_title', "Value cannot be entirely whitespace characters")
+        if django.VERSION >= (1, 9):
+            self.assertFormError(response, 'form', 'title', "This field is required.")
+        else:
+            self.assertFormError(response, 'form', 'title', "This field cannot be blank.")
+
+    def test_whitespace_titles_with_tab(self):
+        post_data = {
+            'title': "\t",  # Single space on purpose
+            'content': "Some content",
+            'slug': 'hello-world',
+            'action-submit': "Submit",
+        }
+        response = self.client.post(reverse('wagtailadmin_pages:add', args=('tests', 'simplepage', self.root_page.id)), post_data)
+
+        # Check that a form error was raised
+        if django.VERSION >= (1, 9):
+            self.assertFormError(response, 'form', 'title', "This field is required.")
+        else:
+            self.assertFormError(response, 'form', 'title', "This field cannot be blank.")
+
+    def test_whitespace_titles_with_tab_in_seo_title(self):
+        post_data = {
+            'title': "Hello",
+            'content': "Some content",
+            'slug': 'hello-world',
+            'action-submit': "Submit",
+            'seo_title': '\t'
+        }
+        response = self.client.post(reverse('wagtailadmin_pages:add', args=('tests', 'simplepage', self.root_page.id)), post_data)
+
+        # Should be successful, as seo_title is not required
+        self.assertEqual(response.status_code, 302)
+
+        # The tab should be automatically stripped from the seo_title
+        page = Page.objects.order_by('-id').first()
+        self.assertEqual(page.seo_title, '')
 
     def test_long_slug(self):
         post_data = {

wagtail/wagtailadmin/views/pages.py

@@ -1,3 +1,4 @@
+import django
 from django.http import Http404, HttpResponse
 from django.shortcuts import render, redirect, get_object_or_404
 from django.core.exceptions import ValidationError, PermissionDenied
@@ -18,7 +19,6 @@ from wagtail.wagtailadmin import signals
 
 from wagtail.wagtailcore import hooks
 from wagtail.wagtailcore.models import Page, PageRevision, get_navigation_menu_items
-from wagtail.wagtailcore.validators import validate_not_whitespace
 
 from wagtail.wagtailadmin import messages
 
@@ -316,7 +316,19 @@ def edit(request, page_id):
 
 
 def validate_page_form(form, parent_page, instance=None):
-    # Perform default validation first
+    # Strip whitespace in title and seo_title fields
+    # This is done for us in Django 1.9 and above
+    if django.VERSION < (1, 9):
+        def clean_title():
+            return form.cleaned_data['title'].strip()
+
+        def clean_seo_title():
+            return form.cleaned_data['seo_title'].strip()
+
+        form.clean_title = clean_title
+        form.clean_seo_title = clean_seo_title
+
+    # Perform default validation
     form.full_clean()
 
     if 'slug' in form.cleaned_data:
@@ -329,20 +341,6 @@ def validate_page_form(form, parent_page, instance=None):
         if siblings.filter(slug=form.cleaned_data['slug']).exists():
             form.add_error('slug', ValidationError(_("This slug is already in use")))
 
-    # Check that the title and seo_title are not entirely whitespace
-    if 'title' in form.cleaned_data:
-        try:
-            validate_not_whitespace(form.cleaned_data['title'])
-        except ValidationError as error:
-            form.add_error('title', error)
-
-    if 'seo_title' in form.cleaned_data:
-        if form.cleaned_data['seo_title']:
-            try:
-                validate_not_whitespace(form.cleaned_data['seo_title'])
-            except ValidationError as error:
-                form.add_error('seo_title', error)
-
     # Check scheduled publishing fields
     go_live_at = form.cleaned_data.get('go_live_at')
     expire_at = form.cleaned_data.get('expire_at')

wagtail/wagtailcore/tests/test_validators.py

@@ -1,14 +0,0 @@
-from django.test import TestCase
-from django.core.exceptions import ValidationError
-
-from wagtail.wagtailcore.validators import validate_not_whitespace
-
-
-class TestValidators(TestCase):
-
-    def test_not_whitespace(self):
-        validate_not_whitespace('bar')
-
-        for test_value in (' ', '\t', '\r', '\n', '\r\n'):
-            with self.assertRaises(ValidationError):
-                validate_not_whitespace(test_value)

wagtail/wagtailcore/validators.py

@@ -1,15 +0,0 @@
-import re
-
-from django.core.exceptions import ValidationError
-from django.utils.translation import ugettext as _
-
-WHITESPACE_RE = re.compile(r'^\s+$')
-
-
-def validate_not_whitespace(value):
-    """
-    Validate that a value isn't all whitespace, for example in title and
-    seo_title
-    """
-    if value and WHITESPACE_RE.match(value):
-        raise ValidationError(_('Value cannot be entirely whitespace characters'))