Issue #22604: Fix assertion error in debug mode when dividing a complex number by (nan+0j).

1 files changed, 7 insertions, 2 deletions

diff --git a/Lib/test/test_complex.py b/Lib/test/test_complex.py
index cd55375..0ef9a7a 100644
--- a/Lib/test/test_complex.py
+++ b/Lib/test/test_complex.py
@@ -27,7 +27,7 @@ class ComplexTest(unittest.TestCase):
                 unittest.TestCase.assertAlmostEqual(self, a, b)
 
     def assertCloseAbs(self, x, y, eps=1e-9):
-        """Return true iff floats x and y "are close\""""
+        """Return true iff floats x and y "are close"."""
         # put the one with larger magnitude second
         if abs(x) > abs(y):
             x, y = y, x
@@ -62,7 +62,7 @@ class ComplexTest(unittest.TestCase):
         self.fail(msg.format(x, y))
 
     def assertClose(self, x, y, eps=1e-9):
-        """Return true iff complexes x and y "are close\""""
+        """Return true iff complexes x and y "are close"."""
         self.assertCloseAbs(x.real, y.real, eps)
         self.assertCloseAbs(x.imag, y.imag, eps)
 
@@ -104,6 +104,11 @@ class ComplexTest(unittest.TestCase):
         self.assertAlmostEqual(complex.__truediv__(2+0j, 1+1j), 1-1j)
         self.assertRaises(ZeroDivisionError, complex.__truediv__, 1+1j, 0+0j)
 
+        for denom_real, denom_imag in [(0, NAN), (NAN, 0), (NAN, NAN)]:
+            z = complex(0, 0) / complex(denom_real, denom_imag)
+            self.assertTrue(isnan(z.real))
+            self.assertTrue(isnan(z.imag))
+
     def test_floordiv(self):
         self.assertRaises(TypeError, complex.__floordiv__, 3+0j, 1.5+0j)
         self.assertRaises(TypeError, complex.__floordiv__, 3+0j, 0+0j)