Rev 3377: Fix test_plan_file_merge in http://people.ubuntu.com/~robertc/baz2.0/versioned_files

[Robert Collins]

At http://people.ubuntu.com/~robertc/baz2.0/versioned_files

------------------------------------------------------------
revno: 3377
revision-id: robertc at robertcollins.net-20080612032525-hp52uf3wa7546c4u
parent: robertc at robertcollins.net-20080611072200-04p1qce41wbvipmf
committer: Robert Collins <robertc at robertcollins.net>
branch nick: VersionedFiles.add_api
timestamp: Thu 2008-06-12 13:25:25 +1000
message:
  Fix test_plan_file_merge
modified:
  bzrlib/versionedfile.py        versionedfile.py-20060222045106-5039c71ee3b65490
=== modified file 'bzrlib/versionedfile.py'
--- a/bzrlib/versionedfile.py	2008-06-11 07:22:00 +0000
+++ b/bzrlib/versionedfile.py	2008-06-12 03:25:25 +0000
@@ -1197,8 +1197,14 @@
         # We create a new provider because a fallback may have been added.
         # If we make fallbacks private we can update a stack list and avoid
         # object creation thrashing.
+        keys = set(keys)
+        result = {}
+        if revision.NULL_REVISION in keys:
+            keys.remove(revision.NULL_REVISION)
+            result[revision.NULL_REVISION] = ()
         self._providers = self._providers[:1] + self.fallback_versionedfiles
-        result = _StackedParentsProvider(self._providers).get_parent_map(keys)
+        result.update(
+            _StackedParentsProvider(self._providers).get_parent_map(keys))
         for key, parents in result.iteritems():
             if parents == ():
                 result[key] = (revision.NULL_REVISION,)