Merge branch 'maint/2.x'

docs/changelog.rst

@@ -2,6 +2,18 @@
  importlib_metadata NEWS
 =========================
 
+v3.1.0
+======
+
+* Merge with 2.1.0.
+
+v2.1.0
+======
+
+* #253: When querying for package metadata, the lookup
+  now honors
+  `package normalization rules <https://packaging.python.org/specifications/recording-installed-packages/>`_.
+
 v3.0.0
 ======
 

importlib_metadata/__init__.py

@@ -461,7 +461,7 @@ 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)
+                    or n_low.replace('.', '_').startswith(name.prefix)
                     and n_low.endswith(name.suffixes)
                     # legacy case:
                     or self.is_egg(name) and n_low == 'egg-info'):
@@ -482,12 +482,19 @@ def __init__(self, name):
         self.name = name
         if name is None:
             return
-        self.normalized = name.lower().replace('-', '_')
+        self.normalized = self.normalize(name)
         self.prefix = self.normalized + '-'
         self.exact_matches = [
             self.normalized + suffix for suffix in self.suffixes]
         self.versionless_egg_name = self.normalized + '.egg'
 
+    @staticmethod
+    def normalize(name):
+        """
+        PEP 503 normalization plus dashes as underscores.
+        """
+        return re.sub(r"[-_.]+", "-", name).lower().replace('-', '_')
+
 
 @install
 class MetadataPathFinder(NullFinder, DistributionFinder):

setup.cfg

@@ -38,6 +38,7 @@ testing =
     importlib_resources>=1.3; python_version < "3.9"
     packaging
     pep517
+    unittest2; python_version < "3"
 docs =
     sphinx
     rst.linker

tests/fixtures.py

@@ -99,6 +99,36 @@ def setUp(self):
         build_files(DistInfoPkg.files, self.site_dir)
 
 
+class DistInfoPkgWithDot(OnSysPath, SiteDir):
+    files = {
+        "pkg_dot-1.0.0.dist-info": {
+            "METADATA": """
+                Name: pkg.dot
+                Version: 1.0.0
+                """,
+            },
+        }
+
+    def setUp(self):
+        super(DistInfoPkgWithDot, self).setUp()
+        build_files(DistInfoPkgWithDot.files, self.site_dir)
+
+
+class DistInfoPkgWithDotLegacy(OnSysPath, SiteDir):
+    files = {
+        "pkg.dot-1.0.0.dist-info": {
+            "METADATA": """
+                Name: pkg.dot
+                Version: 1.0.0
+                """,
+            },
+        }
+
+    def setUp(self):
+        super(DistInfoPkgWithDotLegacy, self).setUp()
+        build_files(DistInfoPkgWithDotLegacy.files, self.site_dir)
+
+
 class DistInfoPkgOffPath(SiteDir):
     def setUp(self):
         super(DistInfoPkgOffPath, self).setUp()

tests/test_api.py

@@ -1,6 +1,10 @@
 import re
 import textwrap
-import unittest
+
+try:
+    import unittest2 as unittest
+except ImportError:
+    import unittest
 
 from . import fixtures
 from importlib_metadata import (
@@ -12,6 +16,7 @@
 class APITests(
         fixtures.EggInfoPkg,
         fixtures.DistInfoPkg,
+        fixtures.DistInfoPkgWithDot,
         fixtures.EggInfoFile,
         unittest.TestCase):
 
@@ -31,6 +36,12 @@ def test_for_name_does_not_exist(self):
         with self.assertRaises(PackageNotFoundError):
             distribution('does-not-exist')
 
+    def test_name_normalization(self):
+        names = 'pkg.dot', 'pkg_dot', 'pkg-dot', 'pkg..dot', 'Pkg.Dot'
+        for name in names:
+            with self.subTest(name):
+                assert distribution(name).metadata['Name'] == 'pkg.dot'
+
     def test_for_top_level(self):
         self.assertEqual(
             distribution('egginfo-pkg').read_text('top_level.txt').strip(),
@@ -146,6 +157,14 @@ def test_more_complex_deps_requires_text(self):
         assert deps == expected
 
 
+class LegacyDots(fixtures.DistInfoPkgWithDotLegacy, unittest.TestCase):
+    def test_name_normalization(self):
+        names = 'pkg.dot', 'pkg_dot', 'pkg-dot', 'pkg..dot', 'Pkg.Dot'
+        for name in names:
+            with self.subTest(name):
+                assert distribution(name).metadata['Name'] == 'pkg.dot'
+
+
 class OffSysPathTests(fixtures.DistInfoPkgOffPath, unittest.TestCase):
     def test_find_distributions_specified_path(self):
         dists = Distribution.discover(path=[str(self.site_dir)])