bpo-45582: Port getpath[p].c to Python (GH-29041)

The getpath.py file is frozen at build time and executed as code over a namespace. It is never imported, nor is it meant to be importable or reusable. However, it should be easier to read, modify, and patch than the previous code.

This commit attempts to preserve every previously tested quirk, but these may be changed in the future to better align platforms.
This commit is contained in:
Steve Dower 2021-12-03 00:08:42 +00:00 committed by GitHub
parent 9f2f7e4226
commit 99fcf15052
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
40 changed files with 3686 additions and 3838 deletions

View file

@ -334,43 +334,55 @@ def expandvars(path):
# It should be understood that this may change the meaning of the path
# if it contains symbolic links!
def normpath(path):
"""Normalize path, eliminating double slashes, etc."""
path = os.fspath(path)
if isinstance(path, bytes):
sep = b'/'
empty = b''
dot = b'.'
dotdot = b'..'
else:
sep = '/'
empty = ''
dot = '.'
dotdot = '..'
if path == empty:
return dot
initial_slashes = path.startswith(sep)
# POSIX allows one or two initial slashes, but treats three or more
# as single slash.
# (see http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap04.html#tag_04_13)
if (initial_slashes and
path.startswith(sep*2) and not path.startswith(sep*3)):
initial_slashes = 2
comps = path.split(sep)
new_comps = []
for comp in comps:
if comp in (empty, dot):
continue
if (comp != dotdot or (not initial_slashes and not new_comps) or
(new_comps and new_comps[-1] == dotdot)):
new_comps.append(comp)
elif new_comps:
new_comps.pop()
comps = new_comps
path = sep.join(comps)
if initial_slashes:
path = sep*initial_slashes + path
return path or dot
try:
from posix import _path_normpath
except ImportError:
def normpath(path):
"""Normalize path, eliminating double slashes, etc."""
path = os.fspath(path)
if isinstance(path, bytes):
sep = b'/'
empty = b''
dot = b'.'
dotdot = b'..'
else:
sep = '/'
empty = ''
dot = '.'
dotdot = '..'
if path == empty:
return dot
initial_slashes = path.startswith(sep)
# POSIX allows one or two initial slashes, but treats three or more
# as single slash.
# (see http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap04.html#tag_04_13)
if (initial_slashes and
path.startswith(sep*2) and not path.startswith(sep*3)):
initial_slashes = 2
comps = path.split(sep)
new_comps = []
for comp in comps:
if comp in (empty, dot):
continue
if (comp != dotdot or (not initial_slashes and not new_comps) or
(new_comps and new_comps[-1] == dotdot)):
new_comps.append(comp)
elif new_comps:
new_comps.pop()
comps = new_comps
path = sep.join(comps)
if initial_slashes:
path = sep*initial_slashes + path
return path or dot
else:
def normpath(path):
"""Normalize path, eliminating double slashes, etc."""
path = os.fspath(path)
if isinstance(path, bytes):
return os.fsencode(_path_normpath(os.fsdecode(path))) or b"."
return _path_normpath(path) or "."
def abspath(path):