1 files changed, 37 insertions, 0 deletions
diff --git a/Lib/test/test_cmath.py b/Lib/test/test_cmath.py
index 1f884e52a2..0451fb0aa2 100644
--- a/Lib/test/test_cmath.py
+++ b/Lib/test/test_cmath.py
@@ -4,6 +4,8 @@ import test.test_math as test_math
 import unittest
 import cmath, math
 from cmath import phase, polar, rect, pi
+import platform
+import sys
 import sysconfig
 
 INF = float('inf')
@@ -154,6 +156,23 @@ class CMathTests(unittest.TestCase):
         self.assertAlmostEqual(cmath.e, e_expected, places=9,
             msg="cmath.e is {}; should be {}".format(cmath.e, e_expected))
 
+    def test_infinity_and_nan_constants(self):
+        self.assertEqual(cmath.inf.real, math.inf)
+        self.assertEqual(cmath.inf.imag, 0.0)
+        self.assertEqual(cmath.infj.real, 0.0)
+        self.assertEqual(cmath.infj.imag, math.inf)
+
+        self.assertTrue(math.isnan(cmath.nan.real))
+        self.assertEqual(cmath.nan.imag, 0.0)
+        self.assertEqual(cmath.nanj.real, 0.0)
+        self.assertTrue(math.isnan(cmath.nanj.imag))
+
+        # Check consistency with reprs.
+        self.assertEqual(repr(cmath.inf), "inf")
+        self.assertEqual(repr(cmath.infj), "infj")
+        self.assertEqual(repr(cmath.nan), "nan")
+        self.assertEqual(repr(cmath.nanj), "nanj")
+
     def test_user_object(self):
         # Test automatic calling of __complex__ and __float__ by cmath
         # functions
@@ -315,6 +334,18 @@ class CMathTests(unittest.TestCase):
 
     @requires_IEEE_754
     def test_specific_values(self):
+        # Some tests need to be skipped on ancient OS X versions.
+        # See issue #27953.
+        SKIP_ON_TIGER = {'tan0064'}
+
+        osx_version = None
+        if sys.platform == 'darwin':
+            version_txt = platform.mac_ver()[0]
+            try:
+                osx_version = tuple(map(int, version_txt.split('.')))
+            except ValueError:
+                pass
+
         def rect_complex(z):
             """Wrapped version of rect that accepts a complex number instead of
             two float arguments."""
@@ -328,6 +359,12 @@ class CMathTests(unittest.TestCase):
         for id, fn, ar, ai, er, ei, flags in parse_testfile(test_file):
             arg = complex(ar, ai)
             expected = complex(er, ei)
+
+            # Skip certain tests on OS X 10.4.
+            if osx_version is not None and osx_version < (10, 5):
+                if id in SKIP_ON_TIGER:
+                    continue
+
             if fn == 'rect':
                 function = rect_complex
             elif fn == 'polar':