misc: add methods to get next/previous page (#13038)

combo/data/models.py

@@ -162,6 +162,25 @@ class Page(models.Model):
     def get_template_display_name(self):
         return settings.COMBO_PUBLIC_TEMPLATES[self.template_name]['name']
 
+    def get_next_page(self, user=None):
+        pages = Page.get_as_reordered_flat_hierarchy(Page.objects.all())
+        this_page = [x for x in pages if x.id == self.id][0]
+        pages = pages[pages.index(this_page)+1:]
+        for page in pages:
+            if page.is_visible(user):
+                return page
+        return None
+
+    def get_previous_page(self, user=None):
+        pages = Page.get_as_reordered_flat_hierarchy(Page.objects.all())
+        pages.reverse()
+        this_page = [x for x in pages if x.id == self.id][0]
+        pages = pages[pages.index(this_page)+1:]
+        for page in pages:
+            if page.is_visible(user):
+                return page
+        return None
+
     @classmethod
     def get_as_reordered_flat_hierarchy(cls, object_list):
         reordered = []

tests/test_pages.py

@@ -161,3 +161,39 @@ def test_import_export_pages_with_links():
     new_page_2 = Page.objects.all().order_by('order')[1]
     assert CellBase.get_cells(page_id=new_page_1.id)[0].link_page_id == new_page_2.id
     assert CellBase.get_cells(page_id=new_page_2.id)[0].link_page_id == new_page_1.id
+
+def test_next_previous():
+    Page.objects.all().delete()
+    page = Page()
+    page.slug = 'foo'
+    page.save()
+    page2 = Page()
+    page2.slug = 'bar'
+    page2.parent = page
+    page2.order = 1
+    page2.save()
+    page3 = Page()
+    page3.slug = 'baz'
+    page3.parent = page
+    page3.order = 2
+    page3.save()
+
+    assert page.get_next_page(None).id == page2.id
+    assert page.get_previous_page(None) is None
+
+    assert page2.get_next_page(None).id == page3.id
+    assert page2.get_previous_page(None).id == page.id
+
+    page2.public = False
+    page2.save()
+    assert page.get_next_page(None).id == page3.id
+    assert page3.get_previous_page(None).id == page.id
+
+    user1 = User(username='foo')
+    user1.save()
+    assert page.get_next_page(user1).id == page2.id
+    assert page3.get_previous_page(user1).id == page2.id
+
+    page3.public = False
+    page3.save()
+    assert page.get_next_page(None) is None