add next and previous published siblings to Page model

wagtail/tests/fixtures/test.json

@@ -39,7 +39,7 @@
     "model": "wagtailcore.page",
     "fields": {
         "title": "Events",
-        "numchild": 3,
+        "numchild": 4,
         "show_in_menus": true,
         "live": true,
         "depth": 3,
@@ -186,6 +186,34 @@
     }
 },
 
+{
+    "pk": 9,
+    "model": "wagtailcore.page",
+    "fields": {
+        "title": "Ameristralia Day",
+        "numchild": 0,
+        "show_in_menus": true,
+        "live": true,
+        "depth": 4,
+        "content_type": ["tests", "eventpage"],
+        "path": "0001000100010004",
+        "url_path": "/home/events/final-event/",
+        "slug": "final-event",
+        "owner": 3
+    }
+},
+{
+    "pk": 9,
+    "model": "tests.eventpage",
+    "fields": {
+        "date_from": "2015-04-22",
+        "audience": "public",
+        "location": "Ameristralia",
+        "body": "<p>come celebrate the independence of Ameristralia</p>",
+        "cost": "Free"
+    }
+},
+
 {
     "pk": 1,
     "model": "tests.formfield",

wagtail/wagtailcore/models.py

@@ -649,6 +649,21 @@ class Page(MP_Node, ClusterableModel, Indexed):
     def get_siblings(self, inclusive=True):
         return Page.objects.sibling_of(self, inclusive)
 
+    def get_next_published_sibling(self):
+        next_sibling = self.get_next_sibling()
+
+        while next_sibling and not next_sibling.live:
+            next_sibling = next_sibling.get_next_sibling()
+
+        return next_sibling
+
+    def get_prev_published_sibling(self):
+        prev_sibling = self.get_prev_sibling()
+
+        while prev_sibling and not prev_sibling.live:
+            prev_sibling = prev_sibling.get_prev_sibling()
+
+        return prev_sibling
 
 def get_navigation_menu_items():
     # Get all pages that appear in the navigation menu: ones which have children,

wagtail/wagtailcore/tests/test_page_queryset.py

@@ -254,3 +254,21 @@ class TestPageQuerySet(TestCase):
         # Check that the homepage is in the results
         homepage = Page.objects.get(url_path='/home/')
         self.assertTrue(pages.filter(id=homepage.id).exists())
+
+    def test_published_next(self):
+        events_index = Page.objects.get(url_path='/home/events/')
+        current_page = Page.objects.descendant_of(events_index).live().first()
+
+        # All pages must be live
+        while current_page:
+            self.assertTrue(current_page.live)
+            current_page = current_page.get_next_published_sibling()
+
+    def test_published_prev(self):
+        events_index = Page.objects.get(url_path='/home/events/')
+        current_page = Page.objects.descendant_of(events_index).live().last()
+
+        # All pages must be live
+        while current_page:
+            self.assertTrue(current_page.live)
+            current_page = current_page.get_prev_published_sibling()