Have git cache bootstrap repo if repo is corrupt

git_cache.py

Index: git_cache.py
diff --git a/git_cache.py b/git_cache.py
index 75fb29ac4a638cc87353e04b957a53f383bc7dc9..c7229062375619e0e3e7c13e34270195eae944e6 100755
--- a/git_cache.py
+++ b/git_cache.py
@@ -310,7 +310,7 @@ class Mirror(object):
     return os.path.isfile(os.path.join(self.mirror_path, 'config'))
 
   def populate(self, depth=None, shallow=False, bootstrap=False,
-               verbose=False, ignore_lock=False):
+               verbose=False, ignore_lock=False, recurse=True):
     assert self.GetCachePath()
     if shallow and not depth:
       depth = 10000
@@ -374,6 +374,13 @@ class Mirror(object):
         try:
           self.RunGit(fetch_cmd + [spec], cwd=rundir, retry=True)
         except subprocess.CalledProcessError:
+          if spec == '+refs/heads/*:refs/heads/*':
+            if not recurse:
+              # We definitely want to fail if the main refspec fails to fetch.
+              raise
+            # The cache is corrupt, bootstrap it.
+            os.remove(config_file)
+            self.populate(depth, shallow, True, verbose, ignore_lock, False)

[szager1, 2014/06/25 14:48:12]

I would like this better if you split out the logic into sub-methods along these
lines:

if needs_bootstrap():
  bootstrap()
else:
  try:
    fetch()
  except:
    bootstrap()
    fetch()

As it's currently written, this is getting pretty spaghetti-like, and I don't
fully understand the ramifications of, e.g., calling lockfile.lock() twice, or
potentially creating multiple temp dirs.

Also, minor point: os.remove(config_file) can fail on Windows, you need to catch
that (and maybe retry).

           logging.warn('Fetch of %s failed' % spec)
       if tempdir:
         os.rename(tempdir, self.mirror_path)