From ff3d746e8d8e8fbe6de287bd0f4c3a9fa23c18dc Mon Sep 17 00:00:00 2001 From: Luke Plant Date: Tue, 25 Nov 2014 13:29:38 +0000 Subject: Fixed bug in circular dependency algo for migration dependencies. Previous algo only worked if the first item was a part of the loop, and you would get an infinite loop otherwise (see test). To fix this, it was much easier to do a pre-pass. A bonus is that you now get an error message that actually helps you debug the dependency problem. --- tests/migrations/test_graph.py | 14 ++++++++++++++ 1 file changed, 14 insertions(+) (limited to 'tests') diff --git a/tests/migrations/test_graph.py b/tests/migrations/test_graph.py index 5b3f5b8467..abb2b28dc1 100644 --- a/tests/migrations/test_graph.py +++ b/tests/migrations/test_graph.py @@ -134,6 +134,20 @@ class GraphTests(TestCase): graph.forwards_plan, ("app_a", "0003"), ) + def test_circular_graph_2(self): + graph = MigrationGraph() + graph.add_node(('A', '0001'), None) + graph.add_node(('C', '0001'), None) + graph.add_node(('B', '0001'), None) + graph.add_dependency('A.0001', ('A', '0001'),('B', '0001')) + graph.add_dependency('B.0001', ('B', '0001'),('A', '0001')) + graph.add_dependency('C.0001', ('C', '0001'),('B', '0001')) + + self.assertRaises( + CircularDependencyError, + graph.forwards_plan, ('C', '0001') + ) + def test_dfs(self): graph = MigrationGraph() root = ("app_a", "1") -- cgit v1.3