lorry: Set migrated working repositories to be bare

Since commit 50383f3bcce7 "lorry: Crash-proof updates to working git
repos with A/B switching", prepare_working_repos assumes that the
existing working repositories are bare.  migrate_oldstyle_repos did
not ensure that, although it did discard any working tree.

Run "git config" to set the core.bare and core.logallrefupdates flags
appropriately.

1 files changed, 7 insertions, 0 deletions

diff --git a/lorry b/lorry
index e37261c..279a175 100755
--- a/lorry
+++ b/lorry
@@ -423,6 +423,13 @@ class Lorry(cliapp.Application):
                 if not os.path.exists(old_gitdir):
                     old_gitdir = old_repo
 
+                # Ensure that it's bare
+                self.run_program(['git', 'config', 'core.bare', 'true'],
+                                 cwd=old_gitdir)
+                self.run_program(['git', 'config', 'core.logallrefupdates',
+                                  'false'],
+                                 cwd=old_gitdir)
+
                 self.write_update_count(old_gitdir, 1)
 
                 # Move it to new name, and remove top-level directory if we