diff options
Diffstat (limited to 'third_party/python/setuptools/setuptools/_vendor/importlib_resources/abc.py')
-rw-r--r-- | third_party/python/setuptools/setuptools/_vendor/importlib_resources/abc.py | 170 |
1 files changed, 170 insertions, 0 deletions
diff --git a/third_party/python/setuptools/setuptools/_vendor/importlib_resources/abc.py b/third_party/python/setuptools/setuptools/_vendor/importlib_resources/abc.py new file mode 100644 index 0000000000..23b6aeafe4 --- /dev/null +++ b/third_party/python/setuptools/setuptools/_vendor/importlib_resources/abc.py @@ -0,0 +1,170 @@ +import abc +import io +import itertools +import pathlib +from typing import Any, BinaryIO, Iterable, Iterator, NoReturn, Text, Optional + +from ._compat import runtime_checkable, Protocol, StrPath + + +__all__ = ["ResourceReader", "Traversable", "TraversableResources"] + + +class ResourceReader(metaclass=abc.ABCMeta): + """Abstract base class for loaders to provide resource reading support.""" + + @abc.abstractmethod + def open_resource(self, resource: Text) -> BinaryIO: + """Return an opened, file-like object for binary reading. + + The 'resource' argument is expected to represent only a file name. + If the resource cannot be found, FileNotFoundError is raised. + """ + # This deliberately raises FileNotFoundError instead of + # NotImplementedError so that if this method is accidentally called, + # it'll still do the right thing. + raise FileNotFoundError + + @abc.abstractmethod + def resource_path(self, resource: Text) -> Text: + """Return the file system path to the specified resource. + + The 'resource' argument is expected to represent only a file name. + If the resource does not exist on the file system, raise + FileNotFoundError. + """ + # This deliberately raises FileNotFoundError instead of + # NotImplementedError so that if this method is accidentally called, + # it'll still do the right thing. + raise FileNotFoundError + + @abc.abstractmethod + def is_resource(self, path: Text) -> bool: + """Return True if the named 'path' is a resource. + + Files are resources, directories are not. + """ + raise FileNotFoundError + + @abc.abstractmethod + def contents(self) -> Iterable[str]: + """Return an iterable of entries in `package`.""" + raise FileNotFoundError + + +class TraversalError(Exception): + pass + + +@runtime_checkable +class Traversable(Protocol): + """ + An object with a subset of pathlib.Path methods suitable for + traversing directories and opening files. + + Any exceptions that occur when accessing the backing resource + may propagate unaltered. + """ + + @abc.abstractmethod + def iterdir(self) -> Iterator["Traversable"]: + """ + Yield Traversable objects in self + """ + + def read_bytes(self) -> bytes: + """ + Read contents of self as bytes + """ + with self.open('rb') as strm: + return strm.read() + + def read_text(self, encoding: Optional[str] = None) -> str: + """ + Read contents of self as text + """ + with self.open(encoding=encoding) as strm: + return strm.read() + + @abc.abstractmethod + def is_dir(self) -> bool: + """ + Return True if self is a directory + """ + + @abc.abstractmethod + def is_file(self) -> bool: + """ + Return True if self is a file + """ + + def joinpath(self, *descendants: StrPath) -> "Traversable": + """ + Return Traversable resolved with any descendants applied. + + Each descendant should be a path segment relative to self + and each may contain multiple levels separated by + ``posixpath.sep`` (``/``). + """ + if not descendants: + return self + names = itertools.chain.from_iterable( + path.parts for path in map(pathlib.PurePosixPath, descendants) + ) + target = next(names) + matches = ( + traversable for traversable in self.iterdir() if traversable.name == target + ) + try: + match = next(matches) + except StopIteration: + raise TraversalError( + "Target not found during traversal.", target, list(names) + ) + return match.joinpath(*names) + + def __truediv__(self, child: StrPath) -> "Traversable": + """ + Return Traversable child in self + """ + return self.joinpath(child) + + @abc.abstractmethod + def open(self, mode='r', *args, **kwargs): + """ + mode may be 'r' or 'rb' to open as text or binary. Return a handle + suitable for reading (same as pathlib.Path.open). + + When opening as text, accepts encoding parameters such as those + accepted by io.TextIOWrapper. + """ + + @property + @abc.abstractmethod + def name(self) -> str: + """ + The base name of this object without any parent references. + """ + + +class TraversableResources(ResourceReader): + """ + The required interface for providing traversable + resources. + """ + + @abc.abstractmethod + def files(self) -> "Traversable": + """Return a Traversable object for the loaded package.""" + + def open_resource(self, resource: StrPath) -> io.BufferedReader: + return self.files().joinpath(resource).open('rb') + + def resource_path(self, resource: Any) -> NoReturn: + raise FileNotFoundError(resource) + + def is_resource(self, path: StrPath) -> bool: + return self.files().joinpath(path).is_file() + + def contents(self) -> Iterator[str]: + return (item.name for item in self.files().iterdir()) |