Mini Shell
import atexit
import contextlib
import fnmatch
import importlib.util
import itertools
import os
import shutil
import sys
import types
import uuid
import warnings
from enum import Enum
from errno import EBADF
from errno import ELOOP
from errno import ENOENT
from errno import ENOTDIR
from functools import partial
from os.path import expanduser
from os.path import expandvars
from os.path import isabs
from os.path import sep
from pathlib import Path
from pathlib import PurePath
from posixpath import sep as posix_sep
from types import ModuleType
from typing import Callable
from typing import Dict
from typing import Iterable
from typing import Iterator
from typing import List
from typing import Optional
from typing import Set
from typing import Tuple
from typing import Type
from typing import TypeVar
from typing import Union
from _pytest.compat import assert_never
from _pytest.outcomes import skip
from _pytest.warning_types import PytestWarning
LOCK_TIMEOUT = 60 * 60 * 24 * 3
_AnyPurePath = TypeVar("_AnyPurePath", bound=PurePath)
# The following function, variables and comments were
# copied from cpython 3.9 Lib/pathlib.py file.
# EBADF - guard against macOS `stat` throwing EBADF
_IGNORED_ERRORS = (ENOENT, ENOTDIR, EBADF, ELOOP)
_IGNORED_WINERRORS = (
21, # ERROR_NOT_READY - drive exists but is not accessible
1921, # ERROR_CANT_RESOLVE_FILENAME - fix for broken symlink pointing to itself
)
def _ignore_error(exception):
return (
getattr(exception, "errno", None) in _IGNORED_ERRORS
or getattr(exception, "winerror", None) in _IGNORED_WINERRORS
)
def get_lock_path(path: _AnyPurePath) -> _AnyPurePath:
return path.joinpath(".lock")
def on_rm_rf_error(
func,
path: str,
excinfo: Union[
BaseException,
Tuple[Type[BaseException], BaseException, Optional[types.TracebackType]],
],
*,
start_path: Path,
) -> bool:
"""Handle known read-only errors during rmtree.
The returned value is used only by our own tests.
"""
if isinstance(excinfo, BaseException):
exc = excinfo
else:
exc = excinfo[1]
# Another process removed the file in the middle of the "rm_rf" (xdist for example).
# More context: https://github.com/pytest-dev/pytest/issues/5974#issuecomment-543799018
if isinstance(exc, FileNotFoundError):
return False
if not isinstance(exc, PermissionError):
warnings.warn(
PytestWarning(f"(rm_rf) error removing {path}\n{type(exc)}: {exc}")
)
return False
if func not in (os.rmdir, os.remove, os.unlink):
if func not in (os.open,):
warnings.warn(
PytestWarning(
"(rm_rf) unknown function {} when removing {}:\n{}: {}".format(
func, path, type(exc), exc
)
)
)
return False
# Chmod + retry.
import stat
def chmod_rw(p: str) -> None:
mode = os.stat(p).st_mode
os.chmod(p, mode | stat.S_IRUSR | stat.S_IWUSR)
# For files, we need to recursively go upwards in the directories to
# ensure they all are also writable.
p = Path(path)
if p.is_file():
for parent in p.parents:
chmod_rw(str(parent))
# Stop when we reach the original path passed to rm_rf.
if parent == start_path:
break
chmod_rw(str(path))
func(path)
return True
def ensure_extended_length_path(path: Path) -> Path:
"""Get the extended-length version of a path (Windows).
On Windows, by default, the maximum length of a path (MAX_PATH) is 260
characters, and operations on paths longer than that fail. But it is possible
to overcome this by converting the path to "extended-length" form before
performing the operation:
https://docs.microsoft.com/en-us/windows/win32/fileio/naming-a-file#maximum-path-length-limitation
On Windows, this function returns the extended-length absolute version of path.
On other platforms it returns path unchanged.
"""
if sys.platform.startswith("win32"):
path = path.resolve()
path = Path(get_extended_length_path_str(str(path)))
return path
def get_extended_length_path_str(path: str) -> str:
"""Convert a path to a Windows extended length path."""
long_path_prefix = "\\\\?\\"
unc_long_path_prefix = "\\\\?\\UNC\\"
if path.startswith((long_path_prefix, unc_long_path_prefix)):
return path
# UNC
if path.startswith("\\\\"):
return unc_long_path_prefix + path[2:]
return long_path_prefix + path
def rm_rf(path: Path) -> None:
"""Remove the path contents recursively, even if some elements
are read-only."""
path = ensure_extended_length_path(path)
onerror = partial(on_rm_rf_error, start_path=path)
if sys.version_info >= (3, 12):
shutil.rmtree(str(path), onexc=onerror)
else:
shutil.rmtree(str(path), onerror=onerror)
def find_prefixed(root: Path, prefix: str) -> Iterator[Path]:
"""Find all elements in root that begin with the prefix, case insensitive."""
l_prefix = prefix.lower()
for x in root.iterdir():
if x.name.lower().startswith(l_prefix):
yield x
def extract_suffixes(iter: Iterable[PurePath], prefix: str) -> Iterator[str]:
"""Return the parts of the paths following the prefix.
:param iter: Iterator over path names.
:param prefix: Expected prefix of the path names.
"""
p_len = len(prefix)
for p in iter:
yield p.name[p_len:]
def find_suffixes(root: Path, prefix: str) -> Iterator[str]:
"""Combine find_prefixes and extract_suffixes."""
return extract_suffixes(find_prefixed(root, prefix), prefix)
def parse_num(maybe_num) -> int:
"""Parse number path suffixes, returns -1 on error."""
try:
return int(maybe_num)
except ValueError:
return -1
def _force_symlink(
root: Path, target: Union[str, PurePath], link_to: Union[str, Path]
) -> None:
"""Helper to create the current symlink.
It's full of race conditions that are reasonably OK to ignore
for the context of best effort linking to the latest test run.
The presumption being that in case of much parallelism
the inaccuracy is going to be acceptable.
"""
current_symlink = root.joinpath(target)
try:
current_symlink.unlink()
except OSError:
pass
try:
current_symlink.symlink_to(link_to)
except Exception:
pass
def make_numbered_dir(root: Path, prefix: str, mode: int = 0o700) -> Path:
"""Create a directory with an increased number as suffix for the given prefix."""
for i in range(10):
# try up to 10 times to create the folder
max_existing = max(map(parse_num, find_suffixes(root, prefix)), default=-1)
new_number = max_existing + 1
new_path = root.joinpath(f"{prefix}{new_number}")
try:
new_path.mkdir(mode=mode)
except Exception:
pass
else:
_force_symlink(root, prefix + "current", new_path)
return new_path
else:
raise OSError(
"could not create numbered dir with prefix "
"{prefix} in {root} after 10 tries".format(prefix=prefix, root=root)
)
def create_cleanup_lock(p: Path) -> Path:
"""Create a lock to prevent premature folder cleanup."""
lock_path = get_lock_path(p)
try:
fd = os.open(str(lock_path), os.O_WRONLY | os.O_CREAT | os.O_EXCL, 0o644)
except FileExistsError as e:
raise OSError(f"cannot create lockfile in {p}") from e
else:
pid = os.getpid()
spid = str(pid).encode()
os.write(fd, spid)
os.close(fd)
if not lock_path.is_file():
raise OSError("lock path got renamed after successful creation")
return lock_path
def register_cleanup_lock_removal(lock_path: Path, register=atexit.register):
"""Register a cleanup function for removing a lock, by default on atexit."""
pid = os.getpid()
def cleanup_on_exit(lock_path: Path = lock_path, original_pid: int = pid) -> None:
current_pid = os.getpid()
if current_pid != original_pid:
# fork
return
try:
lock_path.unlink()
except OSError:
pass
return register(cleanup_on_exit)
def maybe_delete_a_numbered_dir(path: Path) -> None:
"""Remove a numbered directory if its lock can be obtained and it does
not seem to be in use."""
path = ensure_extended_length_path(path)
lock_path = None
try:
lock_path = create_cleanup_lock(path)
parent = path.parent
garbage = parent.joinpath(f"garbage-{uuid.uuid4()}")
path.rename(garbage)
rm_rf(garbage)
except OSError:
# known races:
# * other process did a cleanup at the same time
# * deletable folder was found
# * process cwd (Windows)
return
finally:
# If we created the lock, ensure we remove it even if we failed
# to properly remove the numbered dir.
if lock_path is not None:
try:
lock_path.unlink()
except OSError:
pass
def ensure_deletable(path: Path, consider_lock_dead_if_created_before: float) -> bool:
"""Check if `path` is deletable based on whether the lock file is expired."""
if path.is_symlink():
return False
lock = get_lock_path(path)
try:
if not lock.is_file():
return True
except OSError:
# we might not have access to the lock file at all, in this case assume
# we don't have access to the entire directory (#7491).
return False
try:
lock_time = lock.stat().st_mtime
except Exception:
return False
else:
if lock_time < consider_lock_dead_if_created_before:
# We want to ignore any errors while trying to remove the lock such as:
# - PermissionDenied, like the file permissions have changed since the lock creation;
# - FileNotFoundError, in case another pytest process got here first;
# and any other cause of failure.
with contextlib.suppress(OSError):
lock.unlink()
return True
return False
def try_cleanup(path: Path, consider_lock_dead_if_created_before: float) -> None:
"""Try to cleanup a folder if we can ensure it's deletable."""
if ensure_deletable(path, consider_lock_dead_if_created_before):
maybe_delete_a_numbered_dir(path)
def cleanup_candidates(root: Path, prefix: str, keep: int) -> Iterator[Path]:
"""List candidates for numbered directories to be removed - follows py.path."""
max_existing = max(map(parse_num, find_suffixes(root, prefix)), default=-1)
max_delete = max_existing - keep
paths = find_prefixed(root, prefix)
paths, paths2 = itertools.tee(paths)
numbers = map(parse_num, extract_suffixes(paths2, prefix))
for path, number in zip(paths, numbers):
if number <= max_delete:
yield path
def cleanup_dead_symlinks(root: Path):
for left_dir in root.iterdir():
if left_dir.is_symlink():
if not left_dir.resolve().exists():
left_dir.unlink()
def cleanup_numbered_dir(
root: Path, prefix: str, keep: int, consider_lock_dead_if_created_before: float
) -> None:
"""Cleanup for lock driven numbered directories."""
if not root.exists():
return
for path in cleanup_candidates(root, prefix, keep):
try_cleanup(path, consider_lock_dead_if_created_before)
for path in root.glob("garbage-*"):
try_cleanup(path, consider_lock_dead_if_created_before)
cleanup_dead_symlinks(root)
def make_numbered_dir_with_cleanup(
root: Path,
prefix: str,
keep: int,
lock_timeout: float,
mode: int,
) -> Path:
"""Create a numbered dir with a cleanup lock and remove old ones."""
e = None
for i in range(10):
try:
p = make_numbered_dir(root, prefix, mode)
# Only lock the current dir when keep is not 0
if keep != 0:
lock_path = create_cleanup_lock(p)
register_cleanup_lock_removal(lock_path)
except Exception as exc:
e = exc
else:
consider_lock_dead_if_created_before = p.stat().st_mtime - lock_timeout
# Register a cleanup for program exit
atexit.register(
cleanup_numbered_dir,
root,
prefix,
keep,
consider_lock_dead_if_created_before,
)
return p
assert e is not None
raise e
def resolve_from_str(input: str, rootpath: Path) -> Path:
input = expanduser(input)
input = expandvars(input)
if isabs(input):
return Path(input)
else:
return rootpath.joinpath(input)
def fnmatch_ex(pattern: str, path: Union[str, "os.PathLike[str]"]) -> bool:
"""A port of FNMatcher from py.path.common which works with PurePath() instances.
The difference between this algorithm and PurePath.match() is that the
latter matches "**" glob expressions for each part of the path, while
this algorithm uses the whole path instead.
For example:
"tests/foo/bar/doc/test_foo.py" matches pattern "tests/**/doc/test*.py"
with this algorithm, but not with PurePath.match().
This algorithm was ported to keep backward-compatibility with existing
settings which assume paths match according this logic.
References:
* https://bugs.python.org/issue29249
* https://bugs.python.org/issue34731
"""
path = PurePath(path)
iswin32 = sys.platform.startswith("win")
if iswin32 and sep not in pattern and posix_sep in pattern:
# Running on Windows, the pattern has no Windows path separators,
# and the pattern has one or more Posix path separators. Replace
# the Posix path separators with the Windows path separator.
pattern = pattern.replace(posix_sep, sep)
if sep not in pattern:
name = path.name
else:
name = str(path)
if path.is_absolute() and not os.path.isabs(pattern):
pattern = f"*{os.sep}{pattern}"
return fnmatch.fnmatch(name, pattern)
def parts(s: str) -> Set[str]:
parts = s.split(sep)
return {sep.join(parts[: i + 1]) or sep for i in range(len(parts))}
def symlink_or_skip(src, dst, **kwargs):
"""Make a symlink, or skip the test in case symlinks are not supported."""
try:
os.symlink(str(src), str(dst), **kwargs)
except OSError as e:
skip(f"symlinks not supported: {e}")
class ImportMode(Enum):
"""Possible values for `mode` parameter of `import_path`."""
prepend = "prepend"
append = "append"
importlib = "importlib"
class ImportPathMismatchError(ImportError):
"""Raised on import_path() if there is a mismatch of __file__'s.
This can happen when `import_path` is called multiple times with different filenames that has
the same basename but reside in packages
(for example "/tests1/test_foo.py" and "/tests2/test_foo.py").
"""
def import_path(
p: Union[str, "os.PathLike[str]"],
*,
mode: Union[str, ImportMode] = ImportMode.prepend,
root: Path,
) -> ModuleType:
"""Import and return a module from the given path, which can be a file (a module) or
a directory (a package).
The import mechanism used is controlled by the `mode` parameter:
* `mode == ImportMode.prepend`: the directory containing the module (or package, taking
`__init__.py` files into account) will be put at the *start* of `sys.path` before
being imported with `importlib.import_module`.
* `mode == ImportMode.append`: same as `prepend`, but the directory will be appended
to the end of `sys.path`, if not already in `sys.path`.
* `mode == ImportMode.importlib`: uses more fine control mechanisms provided by `importlib`
to import the module, which avoids having to muck with `sys.path` at all. It effectively
allows having same-named test modules in different places.
:param root:
Used as an anchor when mode == ImportMode.importlib to obtain
a unique name for the module being imported so it can safely be stored
into ``sys.modules``.
:raises ImportPathMismatchError:
If after importing the given `path` and the module `__file__`
are different. Only raised in `prepend` and `append` modes.
"""
mode = ImportMode(mode)
path = Path(p)
if not path.exists():
raise ImportError(path)
if mode is ImportMode.importlib:
module_name = module_name_from_path(path, root)
for meta_importer in sys.meta_path:
spec = meta_importer.find_spec(module_name, [str(path.parent)])
if spec is not None:
break
else:
spec = importlib.util.spec_from_file_location(module_name, str(path))
if spec is None:
raise ImportError(f"Can't find module {module_name} at location {path}")
mod = importlib.util.module_from_spec(spec)
sys.modules[module_name] = mod
spec.loader.exec_module(mod) # type: ignore[union-attr]
insert_missing_modules(sys.modules, module_name)
return mod
pkg_path = resolve_package_path(path)
if pkg_path is not None:
pkg_root = pkg_path.parent
names = list(path.with_suffix("").relative_to(pkg_root).parts)
if names[-1] == "__init__":
names.pop()
module_name = ".".join(names)
else:
pkg_root = path.parent
module_name = path.stem
# Change sys.path permanently: restoring it at the end of this function would cause surprising
# problems because of delayed imports: for example, a conftest.py file imported by this function
# might have local imports, which would fail at runtime if we restored sys.path.
if mode is ImportMode.append:
if str(pkg_root) not in sys.path:
sys.path.append(str(pkg_root))
elif mode is ImportMode.prepend:
if str(pkg_root) != sys.path[0]:
sys.path.insert(0, str(pkg_root))
else:
assert_never(mode)
importlib.import_module(module_name)
mod = sys.modules[module_name]
if path.name == "__init__.py":
return mod
ignore = os.environ.get("PY_IGNORE_IMPORTMISMATCH", "")
if ignore != "1":
module_file = mod.__file__
if module_file is None:
raise ImportPathMismatchError(module_name, module_file, path)
if module_file.endswith((".pyc", ".pyo")):
module_file = module_file[:-1]
if module_file.endswith(os.sep + "__init__.py"):
module_file = module_file[: -(len(os.sep + "__init__.py"))]
try:
is_same = _is_same(str(path), module_file)
except FileNotFoundError:
is_same = False
if not is_same:
raise ImportPathMismatchError(module_name, module_file, path)
return mod
# Implement a special _is_same function on Windows which returns True if the two filenames
# compare equal, to circumvent os.path.samefile returning False for mounts in UNC (#7678).
if sys.platform.startswith("win"):
def _is_same(f1: str, f2: str) -> bool:
return Path(f1) == Path(f2) or os.path.samefile(f1, f2)
else:
def _is_same(f1: str, f2: str) -> bool:
return os.path.samefile(f1, f2)
def module_name_from_path(path: Path, root: Path) -> str:
"""
Return a dotted module name based on the given path, anchored on root.
For example: path="projects/src/tests/test_foo.py" and root="/projects", the
resulting module name will be "src.tests.test_foo".
"""
path = path.with_suffix("")
try:
relative_path = path.relative_to(root)
except ValueError:
# If we can't get a relative path to root, use the full path, except
# for the first part ("d:\\" or "/" depending on the platform, for example).
path_parts = path.parts[1:]
else:
# Use the parts for the relative path to the root path.
path_parts = relative_path.parts
return ".".join(path_parts)
def insert_missing_modules(modules: Dict[str, ModuleType], module_name: str) -> None:
"""
Used by ``import_path`` to create intermediate modules when using mode=importlib.
When we want to import a module as "src.tests.test_foo" for example, we need
to create empty modules "src" and "src.tests" after inserting "src.tests.test_foo",
otherwise "src.tests.test_foo" is not importable by ``__import__``.
"""
module_parts = module_name.split(".")
while module_name:
if module_name not in modules:
try:
# If sys.meta_path is empty, calling import_module will issue
# a warning and raise ModuleNotFoundError. To avoid the
# warning, we check sys.meta_path explicitly and raise the error
# ourselves to fall back to creating a dummy module.
if not sys.meta_path:
raise ModuleNotFoundError
importlib.import_module(module_name)
except ModuleNotFoundError:
module = ModuleType(
module_name,
doc="Empty module created by pytest's importmode=importlib.",
)
modules[module_name] = module
module_parts.pop(-1)
module_name = ".".join(module_parts)
def resolve_package_path(path: Path) -> Optional[Path]:
"""Return the Python package path by looking for the last
directory upwards which still contains an __init__.py.
Returns None if it can not be determined.
"""
result = None
for parent in itertools.chain((path,), path.parents):
if parent.is_dir():
if not parent.joinpath("__init__.py").is_file():
break
if not parent.name.isidentifier():
break
result = parent
return result
def scandir(path: Union[str, "os.PathLike[str]"]) -> List["os.DirEntry[str]"]:
"""Scan a directory recursively, in breadth-first order.
The returned entries are sorted.
"""
entries = []
with os.scandir(path) as s:
# Skip entries with symlink loops and other brokenness, so the caller
# doesn't have to deal with it.
for entry in s:
try:
entry.is_file()
except OSError as err:
if _ignore_error(err):
continue
raise
entries.append(entry)
entries.sort(key=lambda entry: entry.name)
return entries
def visit(
path: Union[str, "os.PathLike[str]"], recurse: Callable[["os.DirEntry[str]"], bool]
) -> Iterator["os.DirEntry[str]"]:
"""Walk a directory recursively, in breadth-first order.
The `recurse` predicate determines whether a directory is recursed.
Entries at each directory level are sorted.
"""
entries = scandir(path)
yield from entries
for entry in entries:
if entry.is_dir() and recurse(entry):
yield from visit(entry.path, recurse)
def absolutepath(path: Union[Path, str]) -> Path:
"""Convert a path to an absolute path using os.path.abspath.
Prefer this over Path.resolve() (see #6523).
Prefer this over Path.absolute() (not public, doesn't normalize).
"""
return Path(os.path.abspath(str(path)))
def commonpath(path1: Path, path2: Path) -> Optional[Path]:
"""Return the common part shared with the other path, or None if there is
no common part.
If one path is relative and one is absolute, returns None.
"""
try:
return Path(os.path.commonpath((str(path1), str(path2))))
except ValueError:
return None
def bestrelpath(directory: Path, dest: Path) -> str:
"""Return a string which is a relative path from directory to dest such
that directory/bestrelpath == dest.
The paths must be either both absolute or both relative.
If no such path can be determined, returns dest.
"""
assert isinstance(directory, Path)
assert isinstance(dest, Path)
if dest == directory:
return os.curdir
# Find the longest common directory.
base = commonpath(directory, dest)
# Can be the case on Windows for two absolute paths on different drives.
# Can be the case for two relative paths without common prefix.
# Can be the case for a relative path and an absolute path.
if not base:
return str(dest)
reldirectory = directory.relative_to(base)
reldest = dest.relative_to(base)
return os.path.join(
# Back from directory to base.
*([os.pardir] * len(reldirectory.parts)),
# Forward from base to dest.
*reldest.parts,
)
# Originates from py. path.local.copy(), with siginficant trims and adjustments.
# TODO(py38): Replace with shutil.copytree(..., symlinks=True, dirs_exist_ok=True)
def copytree(source: Path, target: Path) -> None:
"""Recursively copy a source directory to target."""
assert source.is_dir()
for entry in visit(source, recurse=lambda entry: not entry.is_symlink()):
x = Path(entry)
relpath = x.relative_to(source)
newx = target / relpath
newx.parent.mkdir(exist_ok=True)
if x.is_symlink():
newx.symlink_to(os.readlink(x))
elif x.is_file():
shutil.copyfile(x, newx)
elif x.is_dir():
newx.mkdir(exist_ok=True)
Zerion Mini Shell 1.0