Issue 20968. unittest.mock.MagicMock now supports division

Lib/unittest/mock.py

@@ -1634,7 +1634,9 @@ magic_methods = (
     "bool next "
 )
 
-numerics = "add sub mul div floordiv mod lshift rshift and xor or pow "
+numerics = (
+    "add sub mul div floordiv mod lshift rshift and xor or pow truediv"
+)
 inplace = ' '.join('i%s' % n for n in numerics.split())
 right = ' '.join('r%s' % n for n in numerics.split())
 

Lib/unittest/test/testmock/testmagicmethods.py

@@ -126,6 +126,31 @@ class TestMockingMagicMethods(unittest.TestCase):
         self.assertEqual(7 + mock, mock)
         self.assertEqual(mock.value, 16)
 
+    def test_division(self):
+        original = mock = Mock()
+        mock.value = 32
+        self.assertRaises(TypeError, lambda: mock / 2)
+
+        def truediv(self, other):
+            mock.value /= other
+            return self
+        mock.__truediv__ = truediv
+        self.assertEqual(mock / 2, mock)
+        self.assertEqual(mock.value, 16)
+
+        del mock.__truediv__
+        def itruediv(mock):
+            mock /= 4
+        self.assertRaises(TypeError, itruediv, mock)
+        mock.__itruediv__ = truediv
+        mock /= 8
+        self.assertEqual(mock, original)
+        self.assertEqual(mock.value, 2)
+
+        self.assertRaises(TypeError, lambda: 8 / mock)
+        mock.__rtruediv__ = truediv
+        self.assertEqual(0.5 / mock, mock)
+        self.assertEqual(mock.value, 4)
 
     def test_hash(self):
         mock = Mock()

Misc/NEWS

@@ -30,6 +30,9 @@ Core and Builtins
 Library
 -------
 
+- Issue #20968: unittest.mock.MagicMock now supports division.
+  Patch by Johannes Baiter.
+
 - Fix arbitrary memory access in JSONDecoder.raw_decode with a negative second
   parameter. Bug reported by Guido Vranken.