#
# Copyright (C) 2016 The Android Open Source Project
#
# 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.
#
import itertools
import os
DEFAULT_COMMENT_CHAR = '#'
def ItemsToStr(input_list):
'''Convert item in a list to string.
Args:
input_list: list of objects, the list to convert
Return:
A list of string where objects were converted to string using str function.
None if input list is None.
'''
if not input_list:
return input_list
return list(map(str, input_list))
def ExpandItemDelimiters(input_list,
delimiter,
strip=False,
to_str=False,
remove_empty=True):
'''Expand list items that contain the given delimiter.
Args:
input_list: list of string, a list whose item may contain a delimiter
delimiter: string
strip: bool, whether to strip items after expanding. Default is False
to_str: bool, whether to convert output items in string.
Default is False
remove_empty: bool, whether to remove empty string in result list.
Will not remove None items. Default: True
Returns:
The expended list, which may be the same with input list
if no delimiter found; None if input list is None
'''
if input_list is None:
return None
do_strip = lambda s: s.strip() if strip else s
do_str = lambda s: str(s) if to_str else s
expended_list_generator = (item.split(delimiter) for item in input_list)
result = [
do_strip(do_str(s))
for s in itertools.chain.from_iterable(expended_list_generator)
]
return filter(lambda s: str(s) != '', result) if remove_empty else result
def DeduplicateKeepOrder(input):
'''Remove duplicate items from a sequence while keeping the item order.
Args:
input: a sequence that might have duplicated items.
Returns:
A deduplicated list where item order is kept.
'''
return MergeUniqueKeepOrder(input)
def MergeUniqueKeepOrder(*lists):
'''Merge two list, remove duplicate items, and order.
Args:
lists: any number of lists
Returns:
A merged list where items are unique and original order is kept.
'''
seen = set()
return [
x for x in itertools.chain(*lists) if not (x in seen or seen.add(x))
]
def LoadListFromCommentedTextFile(file_path,
to_str=True,
to_strip=True,
exclude_empty_line=True,
exclude_comment_line=True,
exclude_trailing_comment=True,
remove_duplicates=False,
remove_line_breaks=True,
comment_char=DEFAULT_COMMENT_CHAR):
'''Read commented text file into a list of lines.
Comments or empty lines will be excluded by default.
Args:
file_path: string, path to file
to_str: bool, whether to convert lines to string in result list.
Default value is True.
to_strip: bool, whether to strip lines in result list.
Default value is True.
exclude_empty_line: bool, whether to exclude empty items in result list
Default value is True.
exclude_comment_line: bool, whether to exclude lines that only contains comments.
If a line starts with spaces and ends with comments it
will still be excluded even if to_trim is False.
Default value is True.
exclude_trailing_comment: bool, whether to remove trailing comments
from result items.
Default value is True.
remove_duplicates: bool, whether to remove duplicate items in output list.
Default value is False.
remove_line_breaks: bool, whether to remove trailing trailing
new line characters from result items.
Default value is True.
comment_char: string, character to denote comment.
Default value is pound (#).
Returns:
a list of string. None if file does not exist.
'''
if not os.path.isfile(file_path):
logging.error('The path provided is not a file or does not exist: %s',
file_path)
return None
with open(file_path, 'r') as f:
return LoadListFromCommentedText(
f.read(),
to_str,
to_strip,
exclude_empty_line,
exclude_comment_line,
exclude_trailing_comment,
remove_duplicates,
remove_line_breaks,
comment_char=DEFAULT_COMMENT_CHAR)
def LoadListFromCommentedText(text,
to_str=True,
to_strip=True,
exclude_empty_line=True,
exclude_comment_line=True,
exclude_trailing_comment=True,
remove_duplicates=False,
remove_line_breaks=True,
comment_char=DEFAULT_COMMENT_CHAR):
'''Read commented text into a list of lines.
Comments or empty lines will be excluded by default.
Args:
text: string, text to parse
to_str: bool, whether to convert lines to string in result list.
Default value is True.
to_strip: bool, whether to strip lines in result list.
Default value is True.
exclude_empty_line: bool, whether to exclude empty items in result list
Default value is True.
exclude_comment_line: bool, whether to exclude lines that only contains comments.
If a line starts with spaces and ends with comments it
will still be excluded even if to_trim is False.
Default value is True.
exclude_trailing_comment: bool, whether to remove trailing comments
from result items.
Default value is True.
remove_duplicates: bool, whether to remove duplicate items in output list.
Default value is False.
remove_line_breaks: bool, whether to remove trailing trailing
new line characters from result items.
Default value is True.
comment_char: string, character to denote comment.
Default value is pound (#).
Returns:
a list of string.
'''
lines = text.splitlines(not remove_line_breaks)
if to_str:
lines = map(str, lines)
if exclude_trailing_comment:
def RemoveComment(line):
idx = line.find(comment_char)
if idx < 0:
return line
else:
return line[:idx]
lines = map(RemoveComment, lines)
if to_strip:
lines = map(lambda line: line.strip(), lines)
if exclude_comment_line:
lines = filter(lambda line: not line.strip().startswith(comment_char),
lines)
if exclude_empty_line:
lines = filter(bool, lines)
if remove_duplicates:
lines = DeduplicateKeepOrder(lines)
return lines