Fix __latest__ to actually resolve to the latest migration

7 files changed, 58 insertions, 1 deletions

diff --git a/django/db/migrations/loader.py b/django/db/migrations/loader.py
index 26047b3a85..86987db02c 100644
--- a/django/db/migrations/loader.py
+++ b/django/db/migrations/loader.py
@@ -155,7 +155,7 @@ class MigrationLoader(object):
                 if key[1] == "__first__":
                     return list(self.graph.root_nodes(key[0]))[0]
                 else:
-                    return list(self.graph.root_nodes(key[0]))[-1]
+                    return list(self.graph.leaf_nodes(key[0]))[0]
             except IndexError:
                 if self.ignore_no_migrations:
                     return None
diff --git a/tests/migrations/test_loader.py b/tests/migrations/test_loader.py
index 224deb7374..364faf5e00 100644
--- a/tests/migrations/test_loader.py
+++ b/tests/migrations/test_loader.py
@@ -122,6 +122,26 @@ class LoaderTests(TestCase):
             ],
         )
 
+    @modify_settings(INSTALLED_APPS={'append': 'basic'})
+    @override_settings(MIGRATION_MODULES={
+        "migrations": "migrations.test_migrations_latest",
+        "basic": "migrations.test_migrations_latest_basic",
+    })
+    def test_latest(self):
+        """
+        Makes sure that __latest__ works correctly.
+        """
+        # Load and test the plan
+        migration_loader = MigrationLoader(connection)
+        self.assertEqual(
+            migration_loader.graph.forwards_plan(("migrations", "0001_initial")),
+            [
+                ("basic", "0001_initial"),
+                ("basic", "0002_second"),
+                ("migrations", "0001_initial"),
+            ],
+        )
+
     @override_settings(MIGRATION_MODULES={"migrations": "migrations.test_migrations"})
     def test_name_match(self):
         "Tests prefix name matching"
diff --git a/tests/migrations/test_migrations_latest/0001_initial.py b/tests/migrations/test_migrations_latest/0001_initial.py
new file mode 100644
index 0000000000..e16bb2152d
--- /dev/null
+++ b/tests/migrations/test_migrations_latest/0001_initial.py
@@ -0,0 +1,13 @@
+# -*- coding: utf-8 -*-
+from __future__ import unicode_literals
+
+from django.db import migrations
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("basic", "__latest__"),
+    ]
+
+    operations = []
diff --git a/tests/migrations/test_migrations_latest/__init__.py b/tests/migrations/test_migrations_latest/__init__.py
new file mode 100644
index 0000000000..e69de29bb2
--- /dev/null
+++ b/tests/migrations/test_migrations_latest/__init__.py
diff --git a/tests/migrations/test_migrations_latest_basic/0001_initial.py b/tests/migrations/test_migrations_latest_basic/0001_initial.py
new file mode 100644
index 0000000000..4df0594154
--- /dev/null
+++ b/tests/migrations/test_migrations_latest_basic/0001_initial.py
@@ -0,0 +1,11 @@
+# -*- coding: utf-8 -*-
+from __future__ import unicode_literals
+
+from django.db import migrations
+
+
+class Migration(migrations.Migration):
+
+    dependencies = []
+
+    operations = []
diff --git a/tests/migrations/test_migrations_latest_basic/0002_second.py b/tests/migrations/test_migrations_latest_basic/0002_second.py
new file mode 100644
index 0000000000..49f5b1966c
--- /dev/null
+++ b/tests/migrations/test_migrations_latest_basic/0002_second.py
@@ -0,0 +1,13 @@
+# -*- coding: utf-8 -*-
+from __future__ import unicode_literals
+
+from django.db import migrations
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("basic", "0001_initial"),
+    ]
+
+    operations = []
diff --git a/tests/migrations/test_migrations_latest_basic/__init__.py b/tests/migrations/test_migrations_latest_basic/__init__.py
new file mode 100644
index 0000000000..e69de29bb2
--- /dev/null
+++ b/tests/migrations/test_migrations_latest_basic/__init__.py