diff --git a/lib/importlib_metadata/__init__.py b/lib/importlib_metadata/__init__.py index ed481355..2c71d33c 100644 --- a/lib/importlib_metadata/__init__.py +++ b/lib/importlib_metadata/__init__.py @@ -25,7 +25,7 @@ from ._compat import ( install, ) from ._functools import method_cache, pass_none -from ._itertools import always_iterable, unique_everseen +from ._itertools import always_iterable, bucket, unique_everseen from ._meta import PackageMetadata, SimplePath from contextlib import suppress @@ -39,6 +39,7 @@ __all__ = [ 'DistributionFinder', 'PackageMetadata', 'PackageNotFoundError', + 'SimplePath', 'distribution', 'distributions', 'entry_points', @@ -388,7 +389,7 @@ class Distribution(metaclass=abc.ABCMeta): if not name: raise ValueError("A distribution name is required.") try: - return next(iter(cls.discover(name=name))) + return next(iter(cls._prefer_valid(cls.discover(name=name)))) except StopIteration: raise PackageNotFoundError(name) @@ -412,6 +413,16 @@ class Distribution(metaclass=abc.ABCMeta): resolver(context) for resolver in cls._discover_resolvers() ) + @staticmethod + def _prefer_valid(dists: Iterable[Distribution]) -> Iterable[Distribution]: + """ + Prefer (move to the front) distributions that have metadata. + + Ref python/importlib_resources#489. + """ + buckets = bucket(dists, lambda dist: bool(dist.metadata)) + return itertools.chain(buckets[True], buckets[False]) + @staticmethod def at(path: str | os.PathLike[str]) -> Distribution: """Return a Distribution for the indicated metadata path. diff --git a/lib/importlib_metadata/_itertools.py b/lib/importlib_metadata/_itertools.py index d4ca9b91..79d37198 100644 --- a/lib/importlib_metadata/_itertools.py +++ b/lib/importlib_metadata/_itertools.py @@ -1,3 +1,4 @@ +from collections import defaultdict, deque from itertools import filterfalse @@ -71,3 +72,100 @@ def always_iterable(obj, base_type=(str, bytes)): return iter(obj) except TypeError: return iter((obj,)) + + +# Copied from more_itertools 10.3 +class bucket: + """Wrap *iterable* and return an object that buckets the iterable into + child iterables based on a *key* function. + + >>> iterable = ['a1', 'b1', 'c1', 'a2', 'b2', 'c2', 'b3'] + >>> s = bucket(iterable, key=lambda x: x[0]) # Bucket by 1st character + >>> sorted(list(s)) # Get the keys + ['a', 'b', 'c'] + >>> a_iterable = s['a'] + >>> next(a_iterable) + 'a1' + >>> next(a_iterable) + 'a2' + >>> list(s['b']) + ['b1', 'b2', 'b3'] + + The original iterable will be advanced and its items will be cached until + they are used by the child iterables. This may require significant storage. + + By default, attempting to select a bucket to which no items belong will + exhaust the iterable and cache all values. + If you specify a *validator* function, selected buckets will instead be + checked against it. + + >>> from itertools import count + >>> it = count(1, 2) # Infinite sequence of odd numbers + >>> key = lambda x: x % 10 # Bucket by last digit + >>> validator = lambda x: x in {1, 3, 5, 7, 9} # Odd digits only + >>> s = bucket(it, key=key, validator=validator) + >>> 2 in s + False + >>> list(s[2]) + [] + + """ + + def __init__(self, iterable, key, validator=None): + self._it = iter(iterable) + self._key = key + self._cache = defaultdict(deque) + self._validator = validator or (lambda x: True) + + def __contains__(self, value): + if not self._validator(value): + return False + + try: + item = next(self[value]) + except StopIteration: + return False + else: + self._cache[value].appendleft(item) + + return True + + def _get_values(self, value): + """ + Helper to yield items from the parent iterator that match *value*. + Items that don't match are stored in the local cache as they + are encountered. + """ + while True: + # If we've cached some items that match the target value, emit + # the first one and evict it from the cache. + if self._cache[value]: + yield self._cache[value].popleft() + # Otherwise we need to advance the parent iterator to search for + # a matching item, caching the rest. + else: + while True: + try: + item = next(self._it) + except StopIteration: + return + item_value = self._key(item) + if item_value == value: + yield item + break + elif self._validator(item_value): + self._cache[item_value].append(item) + + def __iter__(self): + for item in self._it: + item_value = self._key(item) + if self._validator(item_value): + self._cache[item_value].append(item) + + yield from self._cache.keys() + + def __getitem__(self, value): + if not self._validator(value): + return iter(()) + + return self._get_values(value) diff --git a/package/requirements-package.txt b/package/requirements-package.txt index 2f21fea4..0eed49c9 100644 --- a/package/requirements-package.txt +++ b/package/requirements-package.txt @@ -1,5 +1,5 @@ apscheduler==3.10.1 -importlib-metadata==8.0.0 +importlib-metadata==8.2.0 importlib-resources==6.4.0 pyinstaller==6.8.0 pyopenssl==24.1.0 diff --git a/requirements.txt b/requirements.txt index b1eb7ca1..e553b686 100644 --- a/requirements.txt +++ b/requirements.txt @@ -16,7 +16,7 @@ gntp==1.0.3 html5lib==1.1 httpagentparser==1.9.5 idna==3.7 -importlib-metadata==8.0.0 +importlib-metadata==8.2.0 importlib-resources==6.4.0 git+https://github.com/Tautulli/ipwhois.git@master#egg=ipwhois IPy==1.01