Merge branch 'master' into bugfix/pickleable-ep

Author: jaraco

.gitlab-ci.yml

@@ -13,18 +13,18 @@ qa:
 
 tests:
   script:
-    - tox -e py27,py34,py35,py36,py37,py38
+    - tox -e py27,py35,py36,py37,py38
 
 coverage:
   script:
-    - tox -e py27-cov,py34-cov,py35-cov,py36-cov,py37-cov,py38-cov
+    - tox -e py27-cov,py35-cov,py36-cov,py37-cov,py38-cov
   artifacts:
     paths:
       - coverage.xml
 
 diffcov:
   script:
-    - tox -e py27-diffcov,py34-diffcov,py35-diffcov,py36-diffcov,py37-diffcov,py38-diffcov
+    - tox -e py27-diffcov,py35-diffcov,py36-diffcov,py37-diffcov,py38-diffcov
 
 docs:
   script:
@@ -41,6 +41,6 @@ codecov:
 release:
   stage: deploy
   only:
-    - /^\d+\.\d+(\.\d+)?([abc]\d*)?$/
+    - /^v\d+\.\d+(\.\d+)?([abc]\d*)?$/
   script:
     - tox -e release

importlib_metadata/__init__.py

@@ -27,7 +27,6 @@
     ModuleNotFoundError,
     MetaPathFinder,
     email_message_from_string,
-    ensure_is_path,
     )
 from importlib import import_module
 from itertools import starmap
@@ -184,8 +183,7 @@ def from_name(cls, name):
             metadata cannot be found.
         """
         for resolver in cls._discover_resolvers():
-            context = DistributionFinder.Context(name=name)
-            dists = cls._maybe_bind(resolver, context)
+            dists = resolver(DistributionFinder.Context(name=name))
             dist = next(dists, None)
             if dist is not None:
                 return dist
@@ -207,32 +205,18 @@ def discover(cls, **kwargs):
             raise ValueError("cannot accept context and kwargs")
         context = context or DistributionFinder.Context(**kwargs)
         return itertools.chain.from_iterable(
-            cls._maybe_bind(resolver, context)
+            resolver(context)
             for resolver in cls._discover_resolvers()
             )
 
-    @staticmethod
-    def _maybe_bind(resolver, context):
-        """
-        Only bind the context to the resolver if as a callable,
-        the resolver accepts the context parameter.
-
-        Workaround for
-        https://gitlab.com/python-devs/importlib_metadata/issues/86
-        """
-        try:  # pragma: nocover
-            return resolver(context)
-        except TypeError:  # pragma: nocover
-            return resolver(name=context.name, path=context.path)
-
     @staticmethod
     def at(path):
         """Return a Distribution for the indicated metadata path
 
         :param path: a string or path-like object
         :return: a concrete Distribution instance for the path
         """
-        return PathDistribution(ensure_is_path(path))
+        return PathDistribution(pathlib.Path(path))
 
     @staticmethod
     def _discover_resolvers():

importlib_metadata/_compat.py

@@ -51,11 +51,35 @@ class MetaPathFinder(object):
 
 
 def install(cls):
-    """Class decorator for installation on sys.meta_path."""
+    """
+    Class decorator for installation on sys.meta_path.
+
+    Adds the backport DistributionFinder to sys.meta_path and
+    attempts to disable the finder functionality of the stdlib
+    DistributionFinder.
+    """
     sys.meta_path.append(cls())
+    disable_stdlib_finder()
     return cls
 
 
+def disable_stdlib_finder():
+    """
+    Give the backport primacy for discovering path-based distributions
+    by monkey-patching the stdlib O_O.
+
+    See #91 for more background for rationale on this sketchy
+    behavior.
+    """
+    def matches(finder):
+        return (
+            finder.__module__ == '_frozen_importlib_external'
+            and hasattr(finder, 'find_distributions')
+            )
+    for finder in filter(matches, sys.meta_path):  # pragma: nocover
+        del finder.find_distributions
+
+
 class NullFinder:
     """
     A "Finder" (aka "MetaClassFinder") that never finds any modules,
@@ -89,12 +113,3 @@ def py2_message_from_string(text):  # nocoverpy3
 
 # https://bitbucket.org/pypy/pypy/issues/3021/ioopen-directory-leaks-a-file-descriptor
 PYPY_OPEN_BUG = getattr(sys, 'pypy_version_info', (9, 9, 9))[:3] <= (7, 1, 1)
-
-
-def ensure_is_path(ob):
-    """Construct a Path from ob even if it's already one.
-    Specialized for Python 3.4.
-    """
-    if (3,) < sys.version_info < (3, 5):
-        ob = str(ob)  # pragma: nocover
-    return pathlib.Path(ob)

importlib_metadata/docs/changelog.rst

@@ -2,11 +2,25 @@
  importlib_metadata NEWS
 =========================
 
-0.24
-====
+v1.1.0
+======
 
+* Dropped support for Python 3.4.
 * EntryPoints are now pickleable. Closes #96.
 
+v1.0.0
+======
+
+* Project adopts semver for versioning.
+
+* Removed compatibility shim introduced in 0.23.
+
+* For better compatibility with the stdlib implementation and to
+  avoid the same distributions being discovered by the stdlib and
+  backport implementations, the backport now disables the
+  stdlib DistributionFinder during initialization (import time).
+  Closes #91 and closes #100.
+
 0.23
 ====
 * Added a compatibility shim to prevent failures on beta releases

importlib_metadata/docs/index.rst

@@ -12,8 +12,9 @@ efficient ``pkg_resources`` package.
 
 ``importlib_metadata`` is a backport of Python 3.8's standard library
 `importlib.metadata`_ module for Python 2.7, and 3.4 through 3.7.  Users of
-Python 3.8 and beyond are encouraged to use the standard library module, and
-in fact for these versions, ``importlib_metadata`` just shadows that module.
+Python 3.8 and beyond are encouraged to use the standard library module.
+When imported on Python 3.8 and later, ``importlib_metadata`` replaces the
+DistributionFinder behavior from the stdlib, but leaves the API in tact.
 Developers looking for detailed API descriptions should refer to the Python
 3.8 standard library documentation.
 
@@ -50,4 +51,4 @@ Indices and tables
 .. _`metadata API`: https://setuptools.readthedocs.io/en/latest/pkg_resources.html#metadata-api
 .. _`Python 3.7 and newer`: https://docs.python.org/3/library/importlib.html#module-importlib.resources
 .. _`importlib_resources`: https://importlib-resources.readthedocs.io/en/latest/index.html
-.. _`importlib.metadata`: TBD
+.. _`importlib.metadata`: https://docs.python.org/3/library/importlib.metadata.html

setup.cfg

@@ -15,11 +15,11 @@ classifiers =
     Programming Language :: Python :: 2
 
 [options]
-python_requires = >=2.7,!=3.0,!=3.1,!=3.2,!=3.3
+python_requires = >=2.7,!=3.0,!=3.1,!=3.2,!=3.3,!=3.4
 setup_requires = setuptools-scm
 install_requires =
     zipp>=0.5
-    pathlib2; python_version=='3.4.*' or python_version < '3'
+    pathlib2; python_version < '3'
     contextlib2; python_version < '3'
     configparser>=3.5; python_version < '3'
 packages = find:

tox.ini

@@ -1,5 +1,5 @@
 [tox]
-envlist = {py27,py34,py35,py36,py37,py38}{,-cov,-diffcov},qa,docs
+envlist = {py27,py35,py36,py37,py38}{,-cov,-diffcov},qa,docs
 skip_missing_interpreters = True
 
 
@@ -33,7 +33,7 @@ setenv =
     cov: COVERAGE_OPTIONS="-p"
     cov: COVERAGE_FILE={toxinidir}/.coverage
     py27: PYV=2
-    py34,py35,py36,py37,py38: PYV=3
+    py35,py36,py37,py38: PYV=3
     # workaround deprecation warnings in pip's vendored packages
     PYTHONWARNINGS=ignore:Using or importing the ABCs:DeprecationWarning:pip._vendor
 extras =