Remove None and NoneType from parameter types in docstrings.

cleannone.py

# Copyright 2016 Google Inc.
#
# 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.

# Run this with:
#  ag -l 'type ([^:]+): [^\s]+\s*,?\s*(or\s*)?(``None``|``NoneType``|None|NoneType|:class:`NoneType`)' | xargs python ~/Desktop/cleannone.py

import codecs
import re
import shutil
import sys


def insert_optional_at_first_non_space(line):
    line_chars = []

    for i, c in enumerate(line):
        if c == ' ':
            line_chars.append(c)
            continue

        end = line[i:]
        if not end.lower().startswith('(optional') and not end.lower().startswith('optional'):
            line_chars.extend("(Optional) ")
        line_chars.extend(end)
        break

    return ''.join(line_chars)


def main(paths):
    for path in paths:
        # Move to a backup location to edit path in-place.
        shutil.move(path, path + '.bak')

        with codecs.open(path + '.bak', 'r', 'utf-8') as f, codecs.open(path, 'w', 'utf-8') as outf:
            lastlinematched = False
            insertoptional = False

            for line in f:
                if insertoptional:
                    line = insert_optional_at_first_non_space(line)
                    insertoptional = False

                if lastlinematched:
                    # Insert (Optional) in front of param, if not already there.
                    indent, param, end = line.split(':', 2)

                    if len(end.strip()) == 0:
                        # Description starts on the next line, so insert the (Optional) there, instead.
                        insertoptional = True
                    elif not end.lower().startswith(' (optional') and not end.lower().startswith(' optional'):
                        line = indent + ':' + param + ': (Optional)' + end

                lastlinematched = re.search('type ([^:]+): [^\s]+\s*,?\s*(or\s*)?(``None``|``NoneType``|None|:class:`NoneType`)(Type)?', line)

                if lastlinematched:
                    # Delete the "or None" part of the line.
                    line = re.sub(',?\s*(or\s*)?(``None``|``NoneType``|None|:class:`NoneType`)(Type)?', '', line)

                outf.write(line)

if __name__ == '__main__':
    main(sys.argv[1:])