# Copyright 2015 Google Inc. All Rights Reserved.

#

# Licensed under the Apache License, Version 2.0 (the "License");

# you may not use this file except in compliance with the License.

# You may obtain a copy of the License at

#

# http://www.apache.org/licenses/LICENSE-2.0

#

# Unless required by applicable law or agreed to in writing, software

# distributed under the License is distributed on an "AS IS" BASIS,

# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

# See the License for the specific language governing permissions and

# limitations under the License.

"""Interface to file resources.

This module provides functions for interfacing with files: opening, writing, and

querying.

"""

import fnmatch

import os

import re

from lib2to3.pgen2 import tokenize

from yapf.yapflib import errors

from yapf.yapflib import py3compat

from yapf.yapflib import style

def GetDefaultStyleForDir(dirname):

"""Return default style name for a given directory.

Looks for .style.yapf or setup.cfg in the parent directories.

Arguments:

dirname: (unicode) The name of the directory.

Returns:

The filename if found, otherwise return the glboal default (pep8).

"""

dirname = os.path.abspath(dirname)

while True:

# See if we have a .style.yapf file.

style_file = os.path.join(dirname, style.LOCAL_STYLE)

if os.path.exists(style_file):

return style_file

# See if we have a setup.cfg file with a '[yapf]' section.

config_file = os.path.join(dirname, style.SETUP_CONFIG)

if os.path.exists(config_file):

with open(config_file) as fd:

config = py3compat.ConfigParser()

config.read_file(fd)

if config.has_section('yapf'):

return config_file

dirname = os.path.dirname(dirname)

if (not dirname or not os.path.basename(dirname) or

dirname == os.path.abspath(os.path.sep)):

break

global_file = os.path.expanduser(style.GLOBAL_STYLE)

if os.path.exists(global_file):

return global_file

return style.DEFAULT_STYLE

def GetCommandLineFiles(command_line_file_list, recursive, exclude):

"""Return the list of files specified on the command line."""

return _FindPythonFiles(command_line_file_list, recursive, exclude)

def WriteReformattedCode(filename, reformatted_code, in_place, encoding):

"""Emit the reformatted code.

Write the reformatted code into the file, if in_place is True. Otherwise,

write to stdout.

Arguments:

filename: (unicode) The name of the unformatted file.

reformatted_code: (unicode) The reformatted code.

in_place: (bool) If True, then write the reformatted code to the file.

encoding: (unicode) The encoding of the file.

"""

if in_place:

with py3compat.open_with_encoding(filename,

mode='w',

encoding=encoding) as fd:

fd.write(reformatted_code)

else:

py3compat.EncodeAndWriteToStdout(reformatted_code, encoding)

def _FindPythonFiles(filenames, recursive, exclude):

"""Find all Python files."""

python_files = []

for filename in filenames:

if os.path.isdir(filename):

if recursive:

# TODO(morbo): Look into a version of os.walk that can handle recursion.

python_files.extend(

os.path.join(dirpath, f)

for dirpath, _, filelist in os.walk(filename) for f in filelist

if IsPythonFile(os.path.join(dirpath, f)))

else:

raise errors.YapfError(

"directory specified without '--recursive' flag: %s" % filename)

elif os.path.isfile(filename):

python_files.append(filename)

if exclude:

return [f

for f in python_files

if not any(fnmatch.fnmatch(f, p) for p in exclude)]

return python_files

def IsPythonFile(filename):

"""Return True if filename is a Python file."""

if os.path.splitext(filename)[1] == '.py':

return True

try:

with open(filename, 'rb') as fd:

encoding = tokenize.detect_encoding(fd.readline)[0]

# Check for correctness of encoding.

with py3compat.open_with_encoding(filename, encoding=encoding) as fd:

fd.read()

except UnicodeDecodeError:

encoding = 'latin-1'

except (IOError, SyntaxError):

# If we fail to detect encoding (or the encoding cookie is incorrect - which

# will make detect_encoding raise SyntaxError), assume it's not a Python

# file.

return False

try:

with py3compat.open_with_encoding(filename,

mode='r',

encoding=encoding) as fd:

first_line = fd.readlines()[0]

except (IOError, IndexError):

return False

return re.match(r'^#!.*\bpython[23]?\b', first_line)