Adds tag slugurl_trans and drop attempts to patch slugurl

- set_language context manager renamed to use_language
- updated docs about tags

docs/template tags.rst

@@ -11,4 +11,17 @@ Use this template tag to get the url of the current page in another language. Th
 
 .. code-block:: django
 
+    {% load wagtail_modeltranslation %}
     {% change_lang 'pt' %}
+
+slugurl_trans
+===========
+
+Use this template tag as a replacement for `slugurl`.
+
+.. code-block:: django
+
+    {% load wagtail_modeltranslation %}
+    {% slugurl_trans 'default_lang_slug' %}
+    {# or #}
+    {% slugurl_trans 'pt_lang_slug' 'pt' %}

wagtail_modeltranslation/apps.py

@@ -19,6 +19,3 @@ class ModeltranslationConfig(AppConfig):
 
         from .patch_wagtailadmin import patch_wagtail_models
         patch_wagtail_models()
-
-        from .patch_wagtailcore import patch_wagtail_tags
-        patch_wagtail_tags()

wagtail_modeltranslation/contextlib.py

@@ -2,12 +2,12 @@ from django.utils.translation import activate
 from modeltranslation.utils import get_language
 
 
-class set_language:
+class use_language:
     """
     Context manager to safely change language momentarily
 
     Usage:
-        with set_language('en'):
+        with use_language('en'):
             en_url = obj.get_absolute_url()
     """
     def __init__(self, lang):

wagtail_modeltranslation/patch_wagtailcore.py

@@ -1,26 +0,0 @@
-from wagtail.wagtailcore.models import Page
-from wagtail.wagtailcore.templatetags import wagtailcore_tags
-
-from modeltranslation.settings import DEFAULT_LANGUAGE
-
-from .contextlib import set_language
-
-
-# decorate MigrationAutodetector.changes so we can silently remove wagtailcore changes
-def slugurl_decorator(func):
-    def wrapper(context, slug):
-        with set_language(DEFAULT_LANGUAGE):
-            page = Page.objects.filter(slug=slug).first()
-
-        if page:
-            return page.relative_url(context['request'].site)
-        else:
-            # default to original function
-            return func(context, slug)
-
-    return wrapper
-
-
-def patch_wagtail_tags():
-    # decorate slugurl tag so `{% slugurl 'default_lang_slug' %}` always works with original slug
-    wagtailcore_tags.slugurl = slugurl_decorator(wagtailcore_tags.slugurl)

wagtail_modeltranslation/templatetags/wagtail_modeltranslation.py

@@ -5,8 +5,15 @@ import re
 from django import template
 from django.core.urlresolvers import resolve
 from django.utils.translation import activate, get_language
+
 from six import iteritems
 
+from wagtail.wagtailcore.models import Page
+
+from modeltranslation.settings import DEFAULT_LANGUAGE
+
+from wagtail_modeltranslation.contextlib import use_language
+
 register = template.Library()
 
 
@@ -43,3 +50,24 @@ def change_lang(context, lang=None, *args, **kwargs):
             return translated_url
 
     return ''
+
+
+# Alternative to slugurl which uses chosen or default language for language
+@register.simple_tag(takes_context=True)
+def slugurl_trans(context, slug, language=None):
+    """
+    Examples:
+        {% slugurl_trans 'default_lang_slug' %}
+        {% slugurl_trans 'de_lang_slug' 'de' %}
+
+    Returns the URL for the page that has the given slug.
+    """
+    language = language or DEFAULT_LANGUAGE
+
+    with use_language(language):
+        page = Page.objects.filter(slug=slug).first()
+
+    if page:
+        return page.relative_url(context['request'].site)
+    else:
+        return None

wagtail_modeltranslation/tests/tests.py

@@ -70,9 +70,8 @@ class WagtailModeltranslationTransactionTestBase(TransactionTestCase):
 
                 # Reload the patching class to update the imported translator
                 # in order to include the newly registered models
-                from wagtail_modeltranslation import patch_wagtailadmin, patch_wagtailcore
+                from wagtail_modeltranslation import patch_wagtailadmin
                 imp.reload(patch_wagtailadmin)
-                imp.reload(patch_wagtailcore)
 
                 # 3. Reset test models (because autodiscover have already run, those models
                 #    have translation fields, but for languages previously defined. We want
@@ -355,8 +354,11 @@ class WagtailModeltranslationTest(WagtailModeltranslationTestBase):
 
         self.assertRaises(ValidationError, child2.clean)
 
-    def test_slugurl(self):
-        from wagtail.wagtailcore.templatetags.wagtailcore_tags import slugurl
+    def test_slugurl_trans(self):
+        """
+        Assert tag slugurl_trans is immune to user's current language
+        """
+        from wagtail_modeltranslation.templatetags.wagtail_modeltranslation import slugurl_trans
         site_pages = {
             'model': models.TestRootPage,
             'kwargs': {'title': 'root slugurl', },
@@ -374,13 +376,15 @@ class WagtailModeltranslationTest(WagtailModeltranslationTestBase):
         setattr(request_mock, 'site', site)
         context = {'request': request_mock}
 
-        self.assertEqual(slugurl(context, 'root-slugurl'), '/de/')
-        self.assertEqual(slugurl(context, 'child-slugurl'), '/de/child-slugurl/')
+        self.assertEqual(slugurl_trans(context, 'root-slugurl'), '/de/')
+        self.assertEqual(slugurl_trans(context, 'child-slugurl'), '/de/child-slugurl/')
+        self.assertEqual(slugurl_trans(context, 'child-slugurl-en', 'en'), '/de/child-slugurl/')
 
         trans_real.activate('en')
 
-        self.assertEqual(slugurl(context, 'root-slugurl'), '/en/')
-        self.assertEqual(slugurl(context, 'child-slugurl'), '/en/child-slugurl-en/')
+        self.assertEqual(slugurl_trans(context, 'root-slugurl'), '/en/')
+        self.assertEqual(slugurl_trans(context, 'child-slugurl'), '/en/child-slugurl-en/')
+        self.assertEqual(slugurl_trans(context, 'child-slugurl-en', 'en'), '/en/child-slugurl-en/')
 
     def test_original_slug_update(self):
         from wagtail.wagtailcore.models import Page