hgext/fsmonitor/pywatchman/encoding.py

upgrade: register compression as a format variants

Compression is a promising vector for speedup, let us make it easier to check
the compression used and upgrade existing repository.

# Copyright 2016-present Facebook, Inc.
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from __future__ import absolute_import
from __future__ import division
from __future__ import print_function
# no unicode literals

'''Module to deal with filename encoding on the local system, as returned by
Watchman.'''

import sys

from . import (
    compat,
)

if compat.PYTHON3:
    default_local_errors = 'surrogateescape'

    def get_local_encoding():
        if sys.platform == 'win32':
            # Watchman always returns UTF-8 encoded strings on Windows.
            return 'utf-8'
        # On the Python 3 versions we support, sys.getfilesystemencoding never
        # returns None.
        return sys.getfilesystemencoding()
else:
    # Python 2 doesn't support surrogateescape, so use 'strict' by
    # default. Users can register a custom surrogateescape error handler and use
    # that if they so desire.
    default_local_errors = 'strict'

    def get_local_encoding():
        if sys.platform == 'win32':
            # Watchman always returns UTF-8 encoded strings on Windows.
            return 'utf-8'
        fsencoding = sys.getfilesystemencoding()
        if fsencoding is None:
            # This is very unlikely to happen, but if it does, just use UTF-8
            fsencoding = 'utf-8'
        return fsencoding

def encode_local(s):
    return s.encode(get_local_encoding(), default_local_errors)

def decode_local(bs):
    return bs.decode(get_local_encoding(), default_local_errors)