Change Route.level to be zero-indexed

conman/routes/managers.py

@@ -76,13 +76,13 @@ def move_branch(self, old_url, new_url):
 
     def with_level(self, level=None):
         """
-        Annotate the queryset with the (1-indexed) level of each item.
+        Annotate the queryset with the (0-indexed) level of each item.
 
         The level reflects the number of forward slashes in the path.
 
         If "level" is passed in, the queryset will be filtered by the level.
         """
-        qs = self.annotate(level=CharCount('url', char='/'))
+        qs = self.annotate(level=CharCount('url', char='/') - 1)
         if level is None:
             return qs
         return qs.filter(level=level)

conman/routes/models.py

@@ -138,8 +138,8 @@ def handle(self, request, path):
 
     @property
     def level(self):
-        """Fetch the one-indexed 'level' of this item in the URL tree."""
-        return self.url.count('/')
+        """Fetch the 'level' of this item in the URL tree."""
+        return self.url.count('/') - 1  # 0-indexed.
 
     @level.setter
     def level(self, new_value):

tests/routes/test_expressions.py

@@ -27,9 +27,10 @@ def test_query(self):
 
     def test_annotation(self):
         """Test the expression can be used for annotation."""
-        RouteFactory.create(url='/sixth/level/path/including/root/')
+        RouteFactory.create(url='/fifth/level/zero/indexed/path/')
         route = Route.objects.annotate(level=CharCount('url', char='/')).get()
-        self.assertEqual(route.level, 6)  # The number of "/" in the path.
+        # The number of "/" in the path minus one for zero-indexing.
+        self.assertEqual(route.level, 5)
 
     def test_calling_format(self):
         """Ensure the 'char' argument is always a keyword-arg."""

tests/routes/test_managers.py

@@ -209,9 +209,9 @@ def test_no_level_passed(self):
         RouteFactory.create(url='/branch/leaf/')
         result = Route.objects.with_level().values_list('level', 'url')
         expected = (
-            (1, '/'),
-            (2, '/branch/'),
-            (3, '/branch/leaf/'),
+            (0, '/'),
+            (1, '/branch/'),
+            (2, '/branch/leaf/'),
         )
         self.assertCountEqual(result, expected)
 
@@ -220,5 +220,5 @@ def test_level_passed(self):
         RouteFactory.create(url='/')  # Not in QS.
         branch = RouteFactory.create(url='/branch/')
         RouteFactory.create(url='/branch/leaf/')  # Not in QS.
-        result = Route.objects.with_level(2)
+        result = Route.objects.with_level(1)
         self.assertCountEqual(result, [branch])

tests/routes/test_models.py

@@ -48,11 +48,11 @@ def test_url_form_widget(self):
         self.assertIsInstance(widget, forms.TextInput)
 
     def test_level(self):
-        """Route.level is based on the url field."""
+        """Route.level is based on the url field, and is zero-indexed."""
         urls = (
-            (1, '/'),
-            (2, '/branch/'),
-            (3, '/branch/leaf/'),
+            (0, '/'),
+            (1, '/branch/'),
+            (2, '/branch/leaf/'),
         )
         for level, url in urls:
             with self.subTest(url=url):