implement SchemaEditor.alter_index_together()

Author: timgraham

django_mongodb/features.py

@@ -102,9 +102,6 @@ class DatabaseFeatures(BaseDatabaseFeatures):
         # AlterField (unique)
         "schema.tests.SchemaTests.test_unique",
         "schema.tests.SchemaTests.test_unique_and_reverse_m2m",
-        # alter_index_together
-        "migrations.test_operations.OperationTests.test_alter_index_together",
-        "schema.tests.SchemaTests.test_index_together",
         # alter_unique_together
         "migrations.test_operations.OperationTests.test_alter_unique_together",
         "schema.tests.SchemaTests.test_unique_together",

django_mongodb/schema.py

@@ -79,7 +79,18 @@ def remove_field(self, model, field):
             self.connection.database[model._meta.db_table].update_many({}, {"$unset": {column: ""}})
 
     def alter_index_together(self, model, old_index_together, new_index_together):
-        pass
+        olds = {tuple(fields) for fields in old_index_together}
+        news = {tuple(fields) for fields in new_index_together}
+        # Deleted indexes
+        for field_names in olds.difference(news):
+            idx = Index(fields=field_names)
+            idx.set_name_with_model(model)
+            self.remove_index(model, idx)
+        # Created indexes
+        for field_names in news.difference(olds):
+            idx = Index(fields=field_names)
+            idx.set_name_with_model(model)
+            self.add_index(model, idx)
 
     def alter_unique_together(self, model, old_unique_together, new_unique_together):
         pass