Add tests for find_packages_ns()

setuptools/tests/test_find_packages.py

@@ -7,14 +7,15 @@ import platform
 
 import pytest
 
-import setuptools
+from setuptools.extern.six import PY3
 from setuptools import find_packages
 
-find_420_packages = setuptools.PEP420PackageFinder.find
+py3_only = pytest.mark.xfail(not PY3, reason="Test runs on Python 3 only")
+if PY3:
+  from setuptools import find_packages_ns
 
 # modeled after CPython's test.support.can_symlink
 
-
 def can_symlink():
     TESTFN = tempfile.mktemp()
     symlink_path = TESTFN + "can_symlink"
@@ -153,30 +154,35 @@ class TestFindPackages:
     def _assert_packages(self, actual, expected):
         assert set(actual) == set(expected)
 
+    @py3_only
     def test_pep420_ns_package(self):
-        packages = find_420_packages(
+        packages = find_packages_ns(
             self.dist_dir, include=['pkg*'], exclude=['pkg.subpkg.assets'])
         self._assert_packages(packages, ['pkg', 'pkg.nspkg', 'pkg.subpkg'])
 
+    @py3_only
     def test_pep420_ns_package_no_includes(self):
-        packages = find_420_packages(
+        packages = find_packages_ns(
             self.dist_dir, exclude=['pkg.subpkg.assets'])
         self._assert_packages(packages, ['docs', 'pkg', 'pkg.nspkg', 'pkg.subpkg'])
 
+    @py3_only
     def test_pep420_ns_package_no_includes_or_excludes(self):
-        packages = find_420_packages(self.dist_dir)
-        expected = [
-            'docs', 'pkg', 'pkg.nspkg', 'pkg.subpkg', 'pkg.subpkg.assets']
+        packages = find_packages_ns(self.dist_dir)
+        expected = ['docs', 'pkg', 'pkg.nspkg', 'pkg.subpkg', 'pkg.subpkg.assets']
         self._assert_packages(packages, expected)
 
+    @py3_only
     def test_regular_package_with_nested_pep420_ns_packages(self):
         self._touch('__init__.py', self.pkg_dir)
-        packages = find_420_packages(
+        packages = find_packages_ns(
             self.dist_dir, exclude=['docs', 'pkg.subpkg.assets'])
         self._assert_packages(packages, ['pkg', 'pkg.nspkg', 'pkg.subpkg'])
 
+    @py3_only
     def test_pep420_ns_package_no_non_package_dirs(self):
         shutil.rmtree(self.docs_dir)
         shutil.rmtree(os.path.join(self.dist_dir, 'pkg/subpkg/assets'))
-        packages = find_420_packages(self.dist_dir)
+        packages = find_packages_ns(self.dist_dir)
         self._assert_packages(packages, ['pkg', 'pkg.nspkg', 'pkg.subpkg'])
+