hgext/fsmonitor/pywatchman/encoding.py

debian: add less as a build dependency

For builds that run on hermetic environments, it's possible that the "less"
package is not installed by default, yet it's needed for tests to pass after
revision bf5e13e38390 (which sets less as the fallback pager).

# Copyright 2016-present Facebook, Inc.
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are met:
#
#  * Redistributions of source code must retain the above copyright notice,
#    this list of conditions and the following disclaimer.
#
#  * Redistributions in binary form must reproduce the above copyright notice,
#    this list of conditions and the following disclaimer in the documentation
#    and/or other materials provided with the distribution.
#
#  * Neither the name Facebook nor the names of its contributors may be used to
#    endorse or promote products derived from this software without specific
#    prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
# DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
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# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

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)