Rev 5: Handle when there is no common ancestor. in http://bzr.arbash-meinel.com/plugins/per_file_remerge

[John Arbash Meinel]

At http://bzr.arbash-meinel.com/plugins/per_file_remerge

------------------------------------------------------------
revno: 5
revision-id: john at arbash-meinel.com-20080618150604-agwb2hp79jfckpw5
parent: john at arbash-meinel.com-20080618140937-75riqlogk81ac8td
committer: John Arbash Meinel <john at arbash-meinel.com>
branch nick: per_file_remerge
timestamp: Wed 2008-06-18 10:06:04 -0500
message:
  Handle when there is no common ancestor.
-------------- next part --------------
=== modified file 'per_file_remerge.py'
--- a/per_file_remerge.py	2008-06-18 14:09:37 +0000
+++ b/per_file_remerge.py	2008-06-18 15:06:04 +0000
@@ -21,6 +21,8 @@
     errors,
     graph,
     merge,
+    revision,
+    trace,
     ui,
     )
 
@@ -112,10 +114,15 @@
     finally:
         basis_tree.unlock()
 
-    base_revision_id, num_steps = graph_obj.find_unique_lca(
-        this_last_modified_revision_id,
-        other_last_modified_revision_id,
-        count_steps=True)
+    try:
+        base_revision_id, num_steps = graph_obj.find_unique_lca(
+            this_last_modified_revision_id,
+            other_last_modified_revision_id,
+            count_steps=True)
+    except errors.NoCommonAncestor:
+        trace.warning('Could not find a common ancestor for %s, using null:',
+                      file_id)
+        base_revision_id = revision.NULL_REVISION
     return (this_last_modified_revision_id, base_revision_id,
             other_last_modified_revision_id)
 

=== modified file 'test_per_file_remerge.py'
--- a/test_per_file_remerge.py	2008-06-18 14:02:30 +0000
+++ b/test_per_file_remerge.py	2008-06-18 15:06:04 +0000
@@ -117,7 +117,7 @@
                              'new a contents\n'
                              '>>>>>>> MERGE-SOURCE\n', 'tree1/a')
 
-    def test_remerge(self):
+    def test_remerge_all_conflicts(self):
         tree1, tree2 = self.create_criss_cross_merge()
         # Add another file into tree2, to make sure it gets merged, but not
         # touched by remerge
@@ -132,3 +132,21 @@
         self.assertFileEqual('updated a contents\n', 'tree1/a')
         self.assertFileEqual('updated b contents\n', 'tree1/b')
         self.assertFileEqual('c contents\n', 'tree1/c')
+
+    def test_no_common_ancestry(self):
+        # The same file is introduced on both sides, it can conflict, or
+        # whatever, but we shouldn't fail to finish.
+        tree1 = self.make_branch_and_tree('tree1')
+        tree1.commit('common base')
+        tree2 = tree1.bzrdir.sprout('tree2').open_workingtree()
+
+        self.build_tree(['tree1/a', 'tree2/a'])
+        tree1.add(['a'], ['a-id'])
+        tree1.commit('add a')
+        tree2.add(['a'], ['a-id'])
+        tree2.commit('add a')
+
+        # That should conflict
+        self.assertEqual(1, tree1.merge_from_branch(tree2.branch))
+        # There should still be a conflict, but the remerge should complete
+        self.run_bzr(['per-file-remerge'], working_dir='tree1', retcode=1)