localrepo: add ignoremissing parameter to branchtip
Previously, in the namespaces api, the only caller of branchtip was singlenode
which happened to raise the same exception that branchtip raised: KeyError.
This is a minor change but will allow upcoming patches to use repo.branchtip to
not raise an exception if a branch doesn't exist. After that, it will be
possible for extensions to use the namespace api in a stable way.
#!/usr/bin/env python
import errno, os, sys
for f in sys.argv[1:]:
try:
print f, '->', os.readlink(f)
except OSError, err:
if err.errno != errno.EINVAL:
raise
print f, 'not a symlink'
sys.exit(0)