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mirror of https://github.com/arsenetar/dupeguru.git synced 2024-11-16 12:19:03 +00:00
dupeguru/hscommon/util.py
Andrew Senetar 7ba8aa3514
Format files with black
- Format all files with black
- Update tox.ini flake8 arguments to be compatible
- Add black to requirements-extra.txt
- Reduce ignored flake8 rules and fix a few violations
2019-12-31 20:16:27 -06:00

451 lines
13 KiB
Python

# Created By: Virgil Dupras
# Created On: 2011-01-11
# Copyright 2015 Hardcoded Software (http://www.hardcoded.net)
#
# This software is licensed under the "GPLv3" License as described in the "LICENSE" file,
# which should be included with this package. The terms are also available at
# http://www.gnu.org/licenses/gpl-3.0.html
import sys
import os
import os.path as op
import re
from math import ceil
import glob
import shutil
from datetime import timedelta
from .path import Path, pathify, log_io_error
def nonone(value, replace_value):
"""Returns ``value`` if ``value`` is not ``None``. Returns ``replace_value`` otherwise.
"""
if value is None:
return replace_value
else:
return value
def tryint(value, default=0):
"""Tries to convert ``value`` to in ``int`` and returns ``default`` if it fails.
"""
try:
return int(value)
except (TypeError, ValueError):
return default
def minmax(value, min_value, max_value):
"""Returns `value` or one of the min/max bounds if `value` is not between them.
"""
return min(max(value, min_value), max_value)
# --- Sequence related
def dedupe(iterable):
"""Returns a list of elements in ``iterable`` with all dupes removed.
The order of the elements is preserved.
"""
result = []
seen = {}
for item in iterable:
if item in seen:
continue
seen[item] = 1
result.append(item)
return result
def flatten(iterables, start_with=None):
"""Takes a list of lists ``iterables`` and returns a list containing elements of every list.
If ``start_with`` is not ``None``, the result will start with ``start_with`` items, exactly as
if ``start_with`` would be the first item of lists.
"""
result = []
if start_with:
result.extend(start_with)
for iterable in iterables:
result.extend(iterable)
return result
def first(iterable):
"""Returns the first item of ``iterable``.
"""
try:
return next(iter(iterable))
except StopIteration:
return None
def stripfalse(seq):
"""Returns a sequence with all false elements stripped out of seq.
"""
return [x for x in seq if x]
def extract(predicate, iterable):
"""Separates the wheat from the shaft (`predicate` defines what's the wheat), and returns both.
"""
wheat = []
shaft = []
for item in iterable:
if predicate(item):
wheat.append(item)
else:
shaft.append(item)
return wheat, shaft
def allsame(iterable):
"""Returns whether all elements of 'iterable' are the same.
"""
it = iter(iterable)
try:
first_item = next(it)
except StopIteration:
raise ValueError("iterable cannot be empty")
return all(element == first_item for element in it)
def trailiter(iterable, skipfirst=False):
"""Yields (prev_element, element), starting with (None, first_element).
If skipfirst is True, there will be no (None, item1) element and we'll start
directly with (item1, item2).
"""
it = iter(iterable)
if skipfirst:
try:
prev = next(it)
except StopIteration:
return
else:
prev = None
for item in it:
yield prev, item
prev = item
def iterconsume(seq, reverse=True):
"""Iterate over ``seq`` and pops yielded objects.
Because we use the ``pop()`` method, we reverse ``seq`` before proceeding. If you don't need
to do that, set ``reverse`` to ``False``.
This is useful in tight memory situation where you are looping over a sequence of objects that
are going to be discarded afterwards. If you're creating other objects during that iteration
you might want to use this to avoid ``MemoryError``.
"""
if reverse:
seq.reverse()
while seq:
yield seq.pop()
# --- String related
def escape(s, to_escape, escape_with="\\"):
"""Returns ``s`` with characters in ``to_escape`` all prepended with ``escape_with``.
"""
return "".join((escape_with + c if c in to_escape else c) for c in s)
def get_file_ext(filename):
"""Returns the lowercase extension part of filename, without the dot.
"""
pos = filename.rfind(".")
if pos > -1:
return filename[pos + 1 :].lower()
else:
return ""
def rem_file_ext(filename):
"""Returns the filename without extension.
"""
pos = filename.rfind(".")
if pos > -1:
return filename[:pos]
else:
return filename
def pluralize(number, word, decimals=0, plural_word=None):
"""Returns a pluralized string with ``number`` in front of ``word``.
Adds a 's' to s if ``number`` > 1.
``number``: The number to go in front of s
``word``: The word to go after number
``decimals``: The number of digits after the dot
``plural_word``: If the plural rule for word is more complex than adding a 's', specify a plural
"""
number = round(number, decimals)
format = "%%1.%df %%s" % decimals
if number > 1:
if plural_word is None:
word += "s"
else:
word = plural_word
return format % (number, word)
def format_time(seconds, with_hours=True):
"""Transforms seconds in a hh:mm:ss string.
If ``with_hours`` if false, the format is mm:ss.
"""
minus = seconds < 0
if minus:
seconds *= -1
m, s = divmod(seconds, 60)
if with_hours:
h, m = divmod(m, 60)
r = "%02d:%02d:%02d" % (h, m, s)
else:
r = "%02d:%02d" % (m, s)
if minus:
return "-" + r
else:
return r
def format_time_decimal(seconds):
"""Transforms seconds in a strings like '3.4 minutes'.
"""
minus = seconds < 0
if minus:
seconds *= -1
if seconds < 60:
r = pluralize(seconds, "second", 1)
elif seconds < 3600:
r = pluralize(seconds / 60.0, "minute", 1)
elif seconds < 86400:
r = pluralize(seconds / 3600.0, "hour", 1)
else:
r = pluralize(seconds / 86400.0, "day", 1)
if minus:
return "-" + r
else:
return r
SIZE_DESC = ("B", "KB", "MB", "GB", "TB", "PB", "EB", "ZB", "YB")
SIZE_VALS = tuple(1024 ** i for i in range(1, 9))
def format_size(size, decimal=0, forcepower=-1, showdesc=True):
"""Transform a byte count in a formatted string (KB, MB etc..).
``size`` is the number of bytes to format.
``decimal`` is the number digits after the dot.
``forcepower`` is the desired suffix. 0 is B, 1 is KB, 2 is MB etc.. if kept at -1, the suffix
will be automatically chosen (so the resulting number is always below 1024).
if ``showdesc`` is ``True``, the suffix will be shown after the number.
Usage example::
>>> format_size(1234, decimal=2, showdesc=True)
'1.21 KB'
"""
if forcepower < 0:
i = 0
while size >= SIZE_VALS[i]:
i += 1
else:
i = forcepower
if i > 0:
div = SIZE_VALS[i - 1]
else:
div = 1
format = "%%%d.%df" % (decimal, decimal)
negative = size < 0
divided_size = (0.0 + abs(size)) / div
if decimal == 0:
divided_size = ceil(divided_size)
else:
divided_size = ceil(divided_size * (10 ** decimal)) / (10 ** decimal)
if negative:
divided_size *= -1
result = format % divided_size
if showdesc:
result += " " + SIZE_DESC[i]
return result
_valid_xml_range = "\x09\x0A\x0D\x20-\uD7FF\uE000-\uFFFD"
if sys.maxunicode > 0x10000:
_valid_xml_range += "%s-%s" % (chr(0x10000), chr(min(sys.maxunicode, 0x10FFFF)))
RE_INVALID_XML_SUB = re.compile("[^%s]" % _valid_xml_range, re.U).sub
def remove_invalid_xml(s, replace_with=" "):
return RE_INVALID_XML_SUB(replace_with, s)
def multi_replace(s, replace_from, replace_to=""):
"""A function like str.replace() with multiple replacements.
``replace_from`` is a list of things you want to replace. Ex: ['a','bc','d']
``replace_to`` is a list of what you want to replace to.
If ``replace_to`` is a list and has the same length as ``replace_from``, ``replace_from``
items will be translated to corresponding ``replace_to``. A ``replace_to`` list must
have the same length as ``replace_from``
If ``replace_to`` is a string, all ``replace_from`` occurence will be replaced
by that string.
``replace_from`` can also be a str. If it is, every char in it will be translated
as if ``replace_from`` would be a list of chars. If ``replace_to`` is a str and has
the same length as ``replace_from``, it will be transformed into a list.
"""
if isinstance(replace_to, str) and (len(replace_from) != len(replace_to)):
replace_to = [replace_to for r in replace_from]
if len(replace_from) != len(replace_to):
raise ValueError("len(replace_from) must be equal to len(replace_to)")
replace = list(zip(replace_from, replace_to))
for r_from, r_to in [r for r in replace if r[0] in s]:
s = s.replace(r_from, r_to)
return s
# --- Date related
# It might seem like needless namespace pollution, but the speedup gained by this constant is
# significant, so it stays.
ONE_DAY = timedelta(1)
def iterdaterange(start, end):
"""Yields every day between ``start`` and ``end``.
"""
date = start
while date <= end:
yield date
date += ONE_DAY
# --- Files related
@pathify
def modified_after(first_path: Path, second_path: Path):
"""Returns ``True`` if first_path's mtime is higher than second_path's mtime.
If one of the files doesn't exist or is ``None``, it is considered "never modified".
"""
try:
first_mtime = first_path.stat().st_mtime
except (EnvironmentError, AttributeError):
return False
try:
second_mtime = second_path.stat().st_mtime
except (EnvironmentError, AttributeError):
return True
return first_mtime > second_mtime
def find_in_path(name, paths=None):
"""Search for `name` in all directories of `paths` and return the absolute path of the first
occurrence. If `paths` is None, $PATH is used.
"""
if paths is None:
paths = os.environ["PATH"]
if isinstance(paths, str): # if it's not a string, it's already a list
paths = paths.split(os.pathsep)
for path in paths:
if op.exists(op.join(path, name)):
return op.join(path, name)
return None
@log_io_error
@pathify
def delete_if_empty(path: Path, files_to_delete=[]):
"""Deletes the directory at 'path' if it is empty or if it only contains files_to_delete.
"""
if not path.exists() or not path.isdir():
return
contents = path.listdir()
if any(p for p in contents if (p.name not in files_to_delete) or p.isdir()):
return False
for p in contents:
p.remove()
path.rmdir()
return True
def open_if_filename(infile, mode="rb"):
"""If ``infile`` is a string, it opens and returns it. If it's already a file object, it simply returns it.
This function returns ``(file, should_close_flag)``. The should_close_flag is True is a file has
effectively been opened (if we already pass a file object, we assume that the responsibility for
closing the file has already been taken). Example usage::
fp, shouldclose = open_if_filename(infile)
dostuff()
if shouldclose:
fp.close()
"""
if isinstance(infile, Path):
return (infile.open(mode), True)
if isinstance(infile, str):
return (open(infile, mode), True)
else:
return (infile, False)
def ensure_folder(path):
"Create `path` as a folder if it doesn't exist."
if not op.exists(path):
os.makedirs(path)
def ensure_file(path):
"Create `path` as an empty file if it doesn't exist."
if not op.exists(path):
open(path, "w").close()
def delete_files_with_pattern(folder_path, pattern, recursive=True):
"""Delete all files (or folders) in `folder_path` that match the glob `pattern`.
"""
to_delete = glob.glob(op.join(folder_path, pattern))
for fn in to_delete:
if op.isdir(fn):
shutil.rmtree(fn)
else:
os.remove(fn)
if recursive:
subpaths = [op.join(folder_path, fn) for fn in os.listdir(folder_path)]
subfolders = [p for p in subpaths if op.isdir(p)]
for p in subfolders:
delete_files_with_pattern(p, pattern, True)
class FileOrPath:
"""Does the same as :func:`open_if_filename`, but it can be used with a ``with`` statement.
Example::
with FileOrPath(infile):
dostuff()
"""
def __init__(self, file_or_path, mode="rb"):
self.file_or_path = file_or_path
self.mode = mode
self.mustclose = False
self.fp = None
def __enter__(self):
self.fp, self.mustclose = open_if_filename(self.file_or_path, self.mode)
return self.fp
def __exit__(self, exc_type, exc_value, traceback):
if self.fp and self.mustclose:
self.fp.close()