Merge lp:~a-s-usov/bzr-fastimport/no-temp-branches into lp:bzr-fastimport

[Alex Usov]

Correct way to emit "parentless" commit is by issuing reset command, not by creating a temporary branch for it.

Unmerged revisions

357. By Oleksandr Usov <email address hidden> on 2012-08-21

Emit 'reset' command for parentless & baseline commits.
This solves exporting branches with multiple roots without
resorting to use temporary branches

=== modified file 'exporter.py'
--- exporter.py	2012-02-28 16:16:13 +0000
+++ exporter.py	2012-09-06 16:58:20 +0000
@@ -317,6 +317,7 @@
         mark = 1
         self.revid_to_mark[revid] = mark
         file_cmds = self._get_filecommands(bzrlib.revision.NULL_REVISION, revid)
+        self.print_cmd(commands.ResetCommand(ref, None))
         self.print_cmd(self._get_commit_command(ref, mark, revobj, file_cmds))
 
     def emit_commit(self, revid, ref):
@@ -339,16 +340,15 @@
         ncommits = len(self.revid_to_mark)
         nparents = len(revobj.parent_ids)
         if nparents == 0:
-            if ncommits:
-                # This is a parentless commit but it's not the first one
-                # output. We need to create a new temporary branch for it
-                # otherwise git-fast-import will assume the previous commit
-                # was this one's parent
-                ref = self._next_tmp_ref()
             parent = bzrlib.revision.NULL_REVISION
         else:
             parent = revobj.parent_ids[0]
 
+        # For parentless commits we need to issue reset command first, otherwise
+        # git-fast-import will assume previous commit was this one's parent
+        if nparents == 0:
+            self.print_cmd(commands.ResetCommand(ref, None))
+
         # Print the commit
         mark = ncommits + 1
         self.revid_to_mark[revid] = mark
@@ -617,13 +617,3 @@
                                      'valid in git.', git_ref)
                         continue
                 self.print_cmd(commands.ResetCommand(git_ref, ":" + str(mark)))
-
-    def _next_tmp_ref(self):
-        """Return a unique branch name. The name will start with "tmp"."""
-        prefix = 'tmp'
-        if prefix not in self.branch_names:
-            self.branch_names[prefix] = 0
-        else:
-            self.branch_names[prefix] += 1
-            prefix = '%s.%d' % (prefix, self.branch_names[prefix])
-        return 'refs/heads/%s' % prefix

=== modified file 'tests/test_commands.py'
--- tests/test_commands.py	2012-03-01 21:17:18 +0000
+++ tests/test_commands.py	2012-09-06 16:58:20 +0000
@@ -59,7 +59,8 @@
         self.assertIsNot("bla", stream.read())
 
 
-fast_export_baseline_data = """commit refs/heads/master
+fast_export_baseline_data = """reset refs/heads/master
+commit refs/heads/master
 mark :1
 committer
 data 15
@@ -103,7 +104,7 @@
         tree = self.make_branch_and_tree("br")
         tree.commit("pointless")
         data = self.run_bzr("fast-export br")[0]
-        self.assertTrue(data.startswith('commit refs/heads/master\nmark :1\ncommitter'))
+        self.assertTrue(data.startswith('reset refs/heads/master\ncommit refs/heads/master\nmark :1\ncommitter'))
 
     def test_file(self):
         tree = self.make_branch_and_tree("br")