@@ -0,0 +1,677 @@
+import pytest%0Afrom pip._vendor.packaging import specifiers%0A%0Afrom pip._internal.utils.packaging import check_requires_python%0A%0A%0A@pytest.mark.parametrize('version_info, requires_python, expected', %5B%0A    ((3, 6, 5), '== 3.6.4', False),%0A    ((3, 6, 5), '== 3.6.5', True),%0A    ((3, 6, 5), None, True),%0A%5D)%0Adef test_check_requires_python(version_info, requires_python, expected):%0A    actual = check_requires_python(requires_python, version_info)%0A    assert actual == expected%0A%0A%0Adef test_check_requires_python__invalid():%0A    %22%22%22%0A    Test an invalid Requires-Python value.%0A    %22%22%22%0A    with pytest.raises(specifiers.InvalidSpecifier):%0A        check_requires_python('invalid', (3, 6, 5))%0A

Add some tests for check_requires_python().