diff options
Diffstat (limited to 'Lib/importlib/metadata.py')
| -rw-r--r-- | Lib/importlib/metadata.py | 185 |
1 files changed, 119 insertions, 66 deletions
diff --git a/Lib/importlib/metadata.py b/Lib/importlib/metadata.py index 302d61d..36bb42e 100644 --- a/Lib/importlib/metadata.py +++ b/Lib/importlib/metadata.py @@ -1,4 +1,3 @@ -import io import os import re import abc @@ -18,6 +17,7 @@ from contextlib import suppress from importlib import import_module from importlib.abc import MetaPathFinder from itertools import starmap +from typing import Any, List, Optional, Protocol, TypeVar, Union __all__ = [ @@ -31,7 +31,7 @@ __all__ = [ 'metadata', 'requires', 'version', - ] +] class PackageNotFoundError(ModuleNotFoundError): @@ -43,7 +43,7 @@ class PackageNotFoundError(ModuleNotFoundError): @property def name(self): - name, = self.args + (name,) = self.args return name @@ -60,7 +60,7 @@ class EntryPoint( r'(?P<module>[\w.]+)\s*' r'(:\s*(?P<attr>[\w.]+))?\s*' r'(?P<extras>\[.*\])?\s*$' - ) + ) """ A regular expression describing the syntax for an entry point, which might look like: @@ -77,6 +77,8 @@ class EntryPoint( following the attr, and following any extras. """ + dist: Optional['Distribution'] = None + def load(self): """Load the entry point from its definition. If only a module is indicated by the value, return that module. Otherwise, @@ -104,23 +106,27 @@ class EntryPoint( @classmethod def _from_config(cls, config): - return [ + return ( cls(name, value, group) for group in config.sections() for name, value in config.items(group) - ] + ) @classmethod def _from_text(cls, text): config = ConfigParser(delimiters='=') # case sensitive: https://stackoverflow.com/q/1611799/812183 config.optionxform = str - try: - config.read_string(text) - except AttributeError: # pragma: nocover - # Python 2 has no read_string - config.readfp(io.StringIO(text)) - return EntryPoint._from_config(config) + config.read_string(text) + return cls._from_config(config) + + @classmethod + def _from_text_for(cls, text, dist): + return (ep._for(dist) for ep in cls._from_text(text)) + + def _for(self, dist): + self.dist = dist + return self def __iter__(self): """ @@ -132,7 +138,7 @@ class EntryPoint( return ( self.__class__, (self.name, self.value, self.group), - ) + ) class PackagePath(pathlib.PurePosixPath): @@ -159,6 +165,25 @@ class FileHash: return '<FileHash mode: {} value: {}>'.format(self.mode, self.value) +_T = TypeVar("_T") + + +class PackageMetadata(Protocol): + def __len__(self) -> int: + ... # pragma: no cover + + def __contains__(self, item: str) -> bool: + ... # pragma: no cover + + def __getitem__(self, key: str) -> str: + ... # pragma: no cover + + def get_all(self, name: str, failobj: _T = ...) -> Union[List[Any], _T]: + """ + Return all values associated with a possibly multi-valued key. + """ + + class Distribution: """A Python distribution package.""" @@ -210,9 +235,8 @@ class Distribution: raise ValueError("cannot accept context and kwargs") context = context or DistributionFinder.Context(**kwargs) return itertools.chain.from_iterable( - resolver(context) - for resolver in cls._discover_resolvers() - ) + resolver(context) for resolver in cls._discover_resolvers() + ) @staticmethod def at(path): @@ -227,24 +251,24 @@ class Distribution: def _discover_resolvers(): """Search the meta_path for resolvers.""" declared = ( - getattr(finder, 'find_distributions', None) - for finder in sys.meta_path - ) + getattr(finder, 'find_distributions', None) for finder in sys.meta_path + ) return filter(None, declared) @classmethod def _local(cls, root='.'): from pep517 import build, meta + system = build.compat_system(root) builder = functools.partial( meta.build, source_dir=root, system=system, - ) + ) return PathDistribution(zipfile.Path(meta.build_as_zip(builder))) @property - def metadata(self): + def metadata(self) -> PackageMetadata: """Return the parsed metadata for this Distribution. The returned object will have keys that name the various bits of @@ -257,17 +281,22 @@ class Distribution: # effect is to just end up using the PathDistribution's self._path # (which points to the egg-info file) attribute unchanged. or self.read_text('') - ) + ) return email.message_from_string(text) @property + def name(self): + """Return the 'Name' metadata for the distribution package.""" + return self.metadata['Name'] + + @property def version(self): """Return the 'Version' metadata for the distribution package.""" return self.metadata['Version'] @property def entry_points(self): - return EntryPoint._from_text(self.read_text('entry_points.txt')) + return list(EntryPoint._from_text_for(self.read_text('entry_points.txt'), self)) @property def files(self): @@ -324,9 +353,10 @@ class Distribution: section_pairs = cls._read_sections(source.splitlines()) sections = { section: list(map(operator.itemgetter('line'), results)) - for section, results in - itertools.groupby(section_pairs, operator.itemgetter('section')) - } + for section, results in itertools.groupby( + section_pairs, operator.itemgetter('section') + ) + } return cls._convert_egg_info_reqs_to_simple_reqs(sections) @staticmethod @@ -350,6 +380,7 @@ class Distribution: requirement. This method converts the former to the latter. See _test_deps_from_requires_text for an example. """ + def make_condition(name): return name and 'extra == "{name}"'.format(name=name) @@ -438,48 +469,69 @@ class FastPath: names = zip_path.root.namelist() self.joinpath = zip_path.joinpath - return dict.fromkeys( - child.split(posixpath.sep, 1)[0] - for child in names - ) - - def is_egg(self, search): - base = self.base - return ( - base == search.versionless_egg_name - or base.startswith(search.prefix) - and base.endswith('.egg')) + return dict.fromkeys(child.split(posixpath.sep, 1)[0] for child in names) def search(self, name): - for child in self.children(): - n_low = child.lower() - if (n_low in name.exact_matches - or n_low.startswith(name.prefix) - and n_low.endswith(name.suffixes) - # legacy case: - or self.is_egg(name) and n_low == 'egg-info'): - yield self.joinpath(child) + return ( + self.joinpath(child) + for child in self.children() + if name.matches(child, self.base) + ) class Prepared: """ A prepared search for metadata on a possibly-named package. """ - normalized = '' - prefix = '' + + normalized = None suffixes = '.dist-info', '.egg-info' exact_matches = [''][:0] - versionless_egg_name = '' def __init__(self, name): self.name = name if name is None: return - self.normalized = name.lower().replace('-', '_') - self.prefix = self.normalized + '-' - self.exact_matches = [ - self.normalized + suffix for suffix in self.suffixes] - self.versionless_egg_name = self.normalized + '.egg' + self.normalized = self.normalize(name) + self.exact_matches = [self.normalized + suffix for suffix in self.suffixes] + + @staticmethod + def normalize(name): + """ + PEP 503 normalization plus dashes as underscores. + """ + return re.sub(r"[-_.]+", "-", name).lower().replace('-', '_') + + @staticmethod + def legacy_normalize(name): + """ + Normalize the package name as found in the convention in + older packaging tools versions and specs. + """ + return name.lower().replace('-', '_') + + def matches(self, cand, base): + low = cand.lower() + pre, ext = os.path.splitext(low) + name, sep, rest = pre.partition('-') + return ( + low in self.exact_matches + or ext in self.suffixes + and (not self.normalized or name.replace('.', '_') == self.normalized) + # legacy case: + or self.is_egg(base) + and low == 'egg-info' + ) + + def is_egg(self, base): + normalized = self.legacy_normalize(self.name or '') + prefix = normalized + '-' if normalized else '' + versionless_egg_name = normalized + '.egg' if self.name else '' + return ( + base == versionless_egg_name + or base.startswith(prefix) + and base.endswith('.egg') + ) class MetadataPathFinder(DistributionFinder): @@ -500,9 +552,8 @@ class MetadataPathFinder(DistributionFinder): def _search_paths(cls, name, paths): """Find metadata directories in paths heuristically.""" return itertools.chain.from_iterable( - path.search(Prepared(name)) - for path in map(FastPath, paths) - ) + path.search(Prepared(name)) for path in map(FastPath, paths) + ) class PathDistribution(Distribution): @@ -515,9 +566,15 @@ class PathDistribution(Distribution): self._path = path def read_text(self, filename): - with suppress(FileNotFoundError, IsADirectoryError, KeyError, - NotADirectoryError, PermissionError): + with suppress( + FileNotFoundError, + IsADirectoryError, + KeyError, + NotADirectoryError, + PermissionError, + ): return self._path.joinpath(filename).read_text(encoding='utf-8') + read_text.__doc__ = Distribution.read_text.__doc__ def locate_file(self, path): @@ -541,11 +598,11 @@ def distributions(**kwargs): return Distribution.discover(**kwargs) -def metadata(distribution_name): +def metadata(distribution_name) -> PackageMetadata: """Get the metadata for the named package. :param distribution_name: The name of the distribution package to query. - :return: An email.Message containing the parsed metadata. + :return: A PackageMetadata containing the parsed metadata. """ return Distribution.from_name(distribution_name).metadata @@ -565,15 +622,11 @@ def entry_points(): :return: EntryPoint objects for all installed packages. """ - eps = itertools.chain.from_iterable( - dist.entry_points for dist in distributions()) + eps = itertools.chain.from_iterable(dist.entry_points for dist in distributions()) by_group = operator.attrgetter('group') ordered = sorted(eps, key=by_group) grouped = itertools.groupby(ordered, by_group) - return { - group: tuple(eps) - for group, eps in grouped - } + return {group: tuple(eps) for group, eps in grouped} def files(distribution_name): |