metadata: remove Distribution._local

CHANGES.rst

@@ -1,3 +1,13 @@
+v4.10.0
+=======
+
+* #354: Removed ``Distribution._local`` factory. This
+  functionality was created as a demonstration of the
+  possible implementation. Now, the
+  `pep517 <https://pypi.org/project/pep517>`_ package
+  provides this functionality directly through
+  `pep517.meta.load <https://github.com/pypa/pep517/blob/a942316305395f8f757f210e2b16f738af73f8b8/pep517/meta.py#L63-L73>`_.
+
 v4.9.0
 ======
 

importlib_metadata/__init__.py

@@ -576,18 +576,6 @@ def _discover_resolvers():
         )
         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(zipp.Path(meta.build_as_zip(builder)))
-
     @property
     def metadata(self) -> _meta.PackageMetadata:
         """Return the parsed metadata for this Distribution.

pytest.ini

@@ -3,3 +3,5 @@ norecursedirs=dist build .tox .eggs
 addopts=--doctest-modules
 doctest_optionflags=ALLOW_UNICODE ELLIPSIS
 filterwarnings=
+	# Suppress deprecation warning in flake8
+	ignore:SelectableGroups dict interface is deprecated::flake8

setup.cfg

@@ -46,7 +46,6 @@ testing =
 	# local
 	importlib_resources>=1.3; python_version < "3.9"
 	packaging
-	pep517
 	pyfakefs
 	flufl.flake8
 	pytest-perf >= 0.9.2

tests/fixtures.py

@@ -231,21 +231,6 @@ def setUp(self):
         build_files(EggInfoFile.files, prefix=self.site_dir)
 
 
-class LocalPackage:
-    files: FilesDef = {
-        "setup.py": """
-            import setuptools
-            setuptools.setup(name="local-pkg", version="2.0.1")
-            """,
-    }
-
-    def setUp(self):
-        self.fixtures = contextlib.ExitStack()
-        self.addCleanup(self.fixtures.close)
-        self.fixtures.enter_context(tempdir_as_cwd())
-        build_files(self.files)
-
-
 def build_files(file_defs, prefix=pathlib.Path()):
     """Build a set of files/directories, as described by the
 

tests/test_integration.py

@@ -4,7 +4,6 @@
 
 from . import fixtures
 from importlib_metadata import (
-    Distribution,
     MetadataPathFinder,
     _compat,
     distributions,
@@ -44,13 +43,6 @@ def __getattribute__(self, name):
         _compat.disable_stdlib_finder()
 
 
-class LocalProjectTests(fixtures.LocalPackage, unittest.TestCase):
-    def test_find_local(self):
-        dist = Distribution._local()
-        assert dist.metadata['Name'] == 'local-pkg'
-        assert dist.version == '2.0.1'
-
-
 class DistSearch(unittest.TestCase):
     def test_search_dist_dirs(self):
         """