namespaces: add method to return a list of nodes for a given name
This is a helpful method that some extensions can make use of (e.g. for custom
revsets); currently not used in core.
#!/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)