"""Filename globbing utility."""

import os
import re
import fnmatch

__all__ = ["glob", "iglob"]

def glob(pathname):
"""Return a list of paths matching a pathname pattern.

The pattern may contain simple shell-style wildcards a la
fnmatch. However, unlike fnmatch, filenames starting with a
dot are special cases that are not matched by '*' and '?'
patterns.

"""
return list(iglob(pathname))

def iglob(pathname):
"""Return an iterator which yields the paths matching a pathname pattern.

The pattern may contain simple shell-style wildcards a la
fnmatch. However, unlike fnmatch, filenames starting with a
dot are special cases that are not matched by '*' and '?'
patterns.

"""
if not has_magic(pathname):
if os.path.lexists(pathname):
yield pathname
return
dirname, basename = os.path.split(pathname)
if not dirname:
yield from glob1(None, basename)
return
# `os.path.split()` returns the argument itself as a dirname if it is a
# drive or UNC path. Prevent an infinite recursion if a drive or UNC path
# contains magic characters (i.e. r'\\?\C:').
if dirname != pathname and has_magic(dirname):
dirs = iglob(dirname)
else:
dirs = [dirname]
if has_magic(basename):
glob_in_dir = glob1
else:
glob_in_dir = glob0
for dirname in dirs:
for name in glob_in_dir(dirname, basename):
yield os.path.join(dirname, name)

# These 2 helper functions non-recursively glob inside a literal directory.
# They return a list of basenames. `glob1` accepts a pattern while `glob0`
# takes a literal basename (so it only has to check for its existence).

def glob1(dirname, pattern):
if not dirname:
if isinstance(pattern, bytes):
dirname = bytes(os.curdir, 'ASCII')
else:
dirname = os.curdir
try:
names = os.listdir(dirname)
except OSError:
return []
if not _ishidden(pattern):
names = [x for x in names if not _ishidden(x)]
return fnmatch.filter(names, pattern)

def glob0(dirname, basename):
if not basename:
# `os.path.split()` returns an empty basename for paths ending with a
# directory separator. 'q*x/' should match only directories.
if os.path.isdir(dirname):
return [basename]
else:
if os.path.lexists(os.path.join(dirname, basename)):
return [basename]
return []


magic_check = re.compile('([*?[])')
magic_check_bytes = re.compile(b'([*?[])')

def has_magic(s):
if isinstance(s, bytes):
match = magic_check_bytes.search(s)
else:
match = magic_check.search(s)
return match is not None

def _ishidden(path):
return path[0] in ('.', b'.'[0])

def escape(pathname):
"""Escape all special characters.
"""
# Escaping is done by wrapping any of "*?[" between square brackets.
# Metacharacters do not work in the drive part and shouldn't be escaped.
drive, pathname = os.path.splitdrive(pathname)
if isinstance(pathname, bytes):
pathname = magic_check_bytes.sub(br'[\1]', pathname)
else:
pathname = magic_check.sub(r'[\1]', pathname)
return drive + pathname