py3: don?t subscript socket.error On Python 2, socket.error was subscriptable. On Python 3, socket.error is an alias to OSError and is not subscriptable. The except block passes the exception to self.send_error(). This fails on both Python 2 (if it was executed) and Python 3, as it expects a string. Getting the attribute .strerror works on Python 2 and Python 3, and has the same effect as the previous code on Python 2.

from __future__ import absolute_import, print_function
import sys

from mercurial import (
    pycompat,
    util,
)


def main(argv):
    enc = util.urlreq.quote(pycompat.sysbytes(argv[1]))
    if pycompat.iswindows:
        fmt = 'file:///%s'
    else:
        fmt = 'file://%s'
    print(fmt % pycompat.sysstr(enc))


if __name__ == '__main__':
    main(sys.argv)