cpython/Lib/glob.py
Barney Gale 242c7498e5
GH-116380: Move pathlib-specific code from glob to pathlib._abc. (#120011)
In `glob._Globber`, move pathlib-specific methods to `pathlib._abc.PathGlobber` and replace them with abstract methods. Rename `glob._Globber` to `glob._GlobberBase`. As a result, the `glob` module is no longer befouled by code that can only ever apply to pathlib.

No change of behaviour.
2024-06-07 17:59:34 +01:00

552 lines
19 KiB
Python

"""Filename globbing utility."""
import contextlib
import os
import re
import fnmatch
import functools
import itertools
import operator
import stat
import sys
__all__ = ["glob", "iglob", "escape", "translate"]
def glob(pathname, *, root_dir=None, dir_fd=None, recursive=False,
include_hidden=False):
"""Return a list of paths matching a pathname pattern.
The pattern may contain simple shell-style wildcards a la
fnmatch. Unlike fnmatch, filenames starting with a
dot are special cases that are not matched by '*' and '?'
patterns by default.
If `include_hidden` is true, the patterns '*', '?', '**' will match hidden
directories.
If `recursive` is true, the pattern '**' will match any files and
zero or more directories and subdirectories.
"""
return list(iglob(pathname, root_dir=root_dir, dir_fd=dir_fd, recursive=recursive,
include_hidden=include_hidden))
def iglob(pathname, *, root_dir=None, dir_fd=None, recursive=False,
include_hidden=False):
"""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 recursive is true, the pattern '**' will match any files and
zero or more directories and subdirectories.
"""
sys.audit("glob.glob", pathname, recursive)
sys.audit("glob.glob/2", pathname, recursive, root_dir, dir_fd)
if root_dir is not None:
root_dir = os.fspath(root_dir)
else:
root_dir = pathname[:0]
it = _iglob(pathname, root_dir, dir_fd, recursive, False,
include_hidden=include_hidden)
if not pathname or recursive and _isrecursive(pathname[:2]):
try:
s = next(it) # skip empty string
if s:
it = itertools.chain((s,), it)
except StopIteration:
pass
return it
def _iglob(pathname, root_dir, dir_fd, recursive, dironly,
include_hidden=False):
dirname, basename = os.path.split(pathname)
if not has_magic(pathname):
assert not dironly
if basename:
if _lexists(_join(root_dir, pathname), dir_fd):
yield pathname
else:
# Patterns ending with a slash should match only directories
if _isdir(_join(root_dir, dirname), dir_fd):
yield pathname
return
if not dirname:
if recursive and _isrecursive(basename):
yield from _glob2(root_dir, basename, dir_fd, dironly,
include_hidden=include_hidden)
else:
yield from _glob1(root_dir, basename, dir_fd, dironly,
include_hidden=include_hidden)
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, root_dir, dir_fd, recursive, True,
include_hidden=include_hidden)
else:
dirs = [dirname]
if has_magic(basename):
if recursive and _isrecursive(basename):
glob_in_dir = _glob2
else:
glob_in_dir = _glob1
else:
glob_in_dir = _glob0
for dirname in dirs:
for name in glob_in_dir(_join(root_dir, dirname), basename, dir_fd, dironly,
include_hidden=include_hidden):
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, dir_fd, dironly, include_hidden=False):
names = _listdir(dirname, dir_fd, dironly)
if not (include_hidden or _ishidden(pattern)):
names = (x for x in names if not _ishidden(x))
return fnmatch.filter(names, pattern)
def _glob0(dirname, basename, dir_fd, dironly, include_hidden=False):
if basename:
if _lexists(_join(dirname, basename), dir_fd):
return [basename]
else:
# `os.path.split()` returns an empty basename for paths ending with a
# directory separator. 'q*x/' should match only directories.
if _isdir(dirname, dir_fd):
return [basename]
return []
_deprecated_function_message = (
"{name} is deprecated and will be removed in Python {remove}. Use "
"glob.glob and pass a directory to its root_dir argument instead."
)
def glob0(dirname, pattern):
import warnings
warnings._deprecated("glob.glob0", _deprecated_function_message, remove=(3, 15))
return _glob0(dirname, pattern, None, False)
def glob1(dirname, pattern):
import warnings
warnings._deprecated("glob.glob1", _deprecated_function_message, remove=(3, 15))
return _glob1(dirname, pattern, None, False)
# This helper function recursively yields relative pathnames inside a literal
# directory.
def _glob2(dirname, pattern, dir_fd, dironly, include_hidden=False):
assert _isrecursive(pattern)
if not dirname or _isdir(dirname, dir_fd):
yield pattern[:0]
yield from _rlistdir(dirname, dir_fd, dironly,
include_hidden=include_hidden)
# If dironly is false, yields all file names inside a directory.
# If dironly is true, yields only directory names.
def _iterdir(dirname, dir_fd, dironly):
try:
fd = None
fsencode = None
if dir_fd is not None:
if dirname:
fd = arg = os.open(dirname, _dir_open_flags, dir_fd=dir_fd)
else:
arg = dir_fd
if isinstance(dirname, bytes):
fsencode = os.fsencode
elif dirname:
arg = dirname
elif isinstance(dirname, bytes):
arg = bytes(os.curdir, 'ASCII')
else:
arg = os.curdir
try:
with os.scandir(arg) as it:
for entry in it:
try:
if not dironly or entry.is_dir():
if fsencode is not None:
yield fsencode(entry.name)
else:
yield entry.name
except OSError:
pass
finally:
if fd is not None:
os.close(fd)
except OSError:
return
def _listdir(dirname, dir_fd, dironly):
with contextlib.closing(_iterdir(dirname, dir_fd, dironly)) as it:
return list(it)
# Recursively yields relative pathnames inside a literal directory.
def _rlistdir(dirname, dir_fd, dironly, include_hidden=False):
names = _listdir(dirname, dir_fd, dironly)
for x in names:
if include_hidden or not _ishidden(x):
yield x
path = _join(dirname, x) if dirname else x
for y in _rlistdir(path, dir_fd, dironly,
include_hidden=include_hidden):
yield _join(x, y)
def _lexists(pathname, dir_fd):
# Same as os.path.lexists(), but with dir_fd
if dir_fd is None:
return os.path.lexists(pathname)
try:
os.lstat(pathname, dir_fd=dir_fd)
except (OSError, ValueError):
return False
else:
return True
def _isdir(pathname, dir_fd):
# Same as os.path.isdir(), but with dir_fd
if dir_fd is None:
return os.path.isdir(pathname)
try:
st = os.stat(pathname, dir_fd=dir_fd)
except (OSError, ValueError):
return False
else:
return stat.S_ISDIR(st.st_mode)
def _join(dirname, basename):
# It is common if dirname or basename is empty
if not dirname or not basename:
return dirname or basename
return os.path.join(dirname, basename)
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 _isrecursive(pattern):
if isinstance(pattern, bytes):
return pattern == b'**'
else:
return pattern == '**'
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
_special_parts = ('', '.', '..')
_dir_open_flags = os.O_RDONLY | getattr(os, 'O_DIRECTORY', 0)
_no_recurse_symlinks = object()
def translate(pat, *, recursive=False, include_hidden=False, seps=None):
"""Translate a pathname with shell wildcards to a regular expression.
If `recursive` is true, the pattern segment '**' will match any number of
path segments.
If `include_hidden` is true, wildcards can match path segments beginning
with a dot ('.').
If a sequence of separator characters is given to `seps`, they will be
used to split the pattern into segments and match path separators. If not
given, os.path.sep and os.path.altsep (where available) are used.
"""
if not seps:
if os.path.altsep:
seps = (os.path.sep, os.path.altsep)
else:
seps = os.path.sep
escaped_seps = ''.join(map(re.escape, seps))
any_sep = f'[{escaped_seps}]' if len(seps) > 1 else escaped_seps
not_sep = f'[^{escaped_seps}]'
if include_hidden:
one_last_segment = f'{not_sep}+'
one_segment = f'{one_last_segment}{any_sep}'
any_segments = f'(?:.+{any_sep})?'
any_last_segments = '.*'
else:
one_last_segment = f'[^{escaped_seps}.]{not_sep}*'
one_segment = f'{one_last_segment}{any_sep}'
any_segments = f'(?:{one_segment})*'
any_last_segments = f'{any_segments}(?:{one_last_segment})?'
results = []
parts = re.split(any_sep, pat)
last_part_idx = len(parts) - 1
for idx, part in enumerate(parts):
if part == '*':
results.append(one_segment if idx < last_part_idx else one_last_segment)
elif recursive and part == '**':
if idx < last_part_idx:
if parts[idx + 1] != '**':
results.append(any_segments)
else:
results.append(any_last_segments)
else:
if part:
if not include_hidden and part[0] in '*?':
results.append(r'(?!\.)')
results.extend(fnmatch._translate(part, f'{not_sep}*', not_sep))
if idx < last_part_idx:
results.append(any_sep)
res = ''.join(results)
return fr'(?s:{res})\Z'
@functools.lru_cache(maxsize=512)
def _compile_pattern(pat, sep, case_sensitive, recursive=True):
"""Compile given glob pattern to a re.Pattern object (observing case
sensitivity)."""
flags = re.NOFLAG if case_sensitive else re.IGNORECASE
regex = translate(pat, recursive=recursive, include_hidden=True, seps=sep)
return re.compile(regex, flags=flags).match
class _GlobberBase:
"""Abstract class providing shell-style pattern matching and globbing.
"""
def __init__(self, sep, case_sensitive, case_pedantic=False, recursive=False):
self.sep = sep
self.case_sensitive = case_sensitive
self.case_pedantic = case_pedantic
self.recursive = recursive
# Abstract methods
@staticmethod
def lexists(path):
"""Implements os.path.lexists().
"""
raise NotImplementedError
@staticmethod
def scandir(path):
"""Implements os.scandir().
"""
raise NotImplementedError
@staticmethod
def add_slash(path):
"""Returns a path with a trailing slash added.
"""
raise NotImplementedError
@staticmethod
def concat_path(path, text):
"""Implements path concatenation.
"""
raise NotImplementedError
@staticmethod
def parse_entry(entry):
"""Returns the path of an entry yielded from scandir().
"""
raise NotImplementedError
# High-level methods
def compile(self, pat):
return _compile_pattern(pat, self.sep, self.case_sensitive, self.recursive)
def selector(self, parts):
"""Returns a function that selects from a given path, walking and
filtering according to the glob-style pattern parts in *parts*.
"""
if not parts:
return self.select_exists
part = parts.pop()
if self.recursive and part == '**':
selector = self.recursive_selector
elif part in _special_parts:
selector = self.special_selector
elif not self.case_pedantic and magic_check.search(part) is None:
selector = self.literal_selector
else:
selector = self.wildcard_selector
return selector(part, parts)
def special_selector(self, part, parts):
"""Returns a function that selects special children of the given path.
"""
select_next = self.selector(parts)
def select_special(path, exists=False):
path = self.concat_path(self.add_slash(path), part)
return select_next(path, exists)
return select_special
def literal_selector(self, part, parts):
"""Returns a function that selects a literal descendant of a path.
"""
# Optimization: consume and join any subsequent literal parts here,
# rather than leaving them for the next selector. This reduces the
# number of string concatenation operations and calls to add_slash().
while parts and magic_check.search(parts[-1]) is None:
part += self.sep + parts.pop()
select_next = self.selector(parts)
def select_literal(path, exists=False):
path = self.concat_path(self.add_slash(path), part)
return select_next(path, exists=False)
return select_literal
def wildcard_selector(self, part, parts):
"""Returns a function that selects direct children of a given path,
filtering by pattern.
"""
match = None if part == '*' else self.compile(part)
dir_only = bool(parts)
if dir_only:
select_next = self.selector(parts)
def select_wildcard(path, exists=False):
try:
# We must close the scandir() object before proceeding to
# avoid exhausting file descriptors when globbing deep trees.
with self.scandir(path) as scandir_it:
entries = list(scandir_it)
except OSError:
pass
else:
for entry in entries:
if match is None or match(entry.name):
if dir_only:
try:
if not entry.is_dir():
continue
except OSError:
continue
entry_path = self.parse_entry(entry)
if dir_only:
yield from select_next(entry_path, exists=True)
else:
yield entry_path
return select_wildcard
def recursive_selector(self, part, parts):
"""Returns a function that selects a given path and all its children,
recursively, filtering by pattern.
"""
# Optimization: consume following '**' parts, which have no effect.
while parts and parts[-1] == '**':
parts.pop()
# Optimization: consume and join any following non-special parts here,
# rather than leaving them for the next selector. They're used to
# build a regular expression, which we use to filter the results of
# the recursive walk. As a result, non-special pattern segments
# following a '**' wildcard don't require additional filesystem access
# to expand.
follow_symlinks = self.recursive is not _no_recurse_symlinks
if follow_symlinks:
while parts and parts[-1] not in _special_parts:
part += self.sep + parts.pop()
match = None if part == '**' else self.compile(part)
dir_only = bool(parts)
select_next = self.selector(parts)
def select_recursive(path, exists=False):
path = self.add_slash(path)
match_pos = len(str(path))
if match is None or match(str(path), match_pos):
yield from select_next(path, exists)
stack = [path]
while stack:
yield from select_recursive_step(stack, match_pos)
def select_recursive_step(stack, match_pos):
path = stack.pop()
try:
# We must close the scandir() object before proceeding to
# avoid exhausting file descriptors when globbing deep trees.
with self.scandir(path) as scandir_it:
entries = list(scandir_it)
except OSError:
pass
else:
for entry in entries:
is_dir = False
try:
if entry.is_dir(follow_symlinks=follow_symlinks):
is_dir = True
except OSError:
pass
if is_dir or not dir_only:
entry_path = self.parse_entry(entry)
if match is None or match(str(entry_path), match_pos):
if dir_only:
yield from select_next(entry_path, exists=True)
else:
# Optimization: directly yield the path if this is
# last pattern part.
yield entry_path
if is_dir:
stack.append(entry_path)
return select_recursive
def select_exists(self, path, exists=False):
"""Yields the given path, if it exists.
"""
if exists:
# Optimization: this path is already known to exist, e.g. because
# it was returned from os.scandir(), so we skip calling lstat().
yield path
elif self.lexists(path):
yield path
class _StringGlobber(_GlobberBase):
"""Provides shell-style pattern matching and globbing for string paths.
"""
lexists = staticmethod(os.path.lexists)
scandir = staticmethod(os.scandir)
parse_entry = operator.attrgetter('path')
concat_path = operator.add
if os.name == 'nt':
@staticmethod
def add_slash(pathname):
tail = os.path.splitroot(pathname)[2]
if not tail or tail[-1] in '\\/':
return pathname
return f'{pathname}\\'
else:
@staticmethod
def add_slash(pathname):
if not pathname or pathname[-1] == '/':
return pathname
return f'{pathname}/'