diff -r 39697dcd97e3 Lib/test/test_json/test_enum.py
--- a/Lib/test/test_json/test_enum.py	Mon Aug 12 06:51:41 2013 -0700
+++ b/Lib/test/test_json/test_enum.py	Wed Aug 28 00:12:31 2013 -0700
@@ -1,11 +1,12 @@
 from enum import Enum, IntEnum
+from math import isnan
 from test.test_json import PyTest, CTest
 
 SMALL = 1
 BIG = 1<<32
 HUGE = 1<<64
 REALLY_HUGE = 1<<96
 
 class BigNum(IntEnum):
     small = SMALL
     big = BIG
@@ -14,68 +15,119 @@ class BigNum(IntEnum):
 
 E = 2.718281
 PI = 3.141593
 TAU = 2 * PI
 
 class FloatNum(float, Enum):
     e = E
     pi = PI
     tau = TAU
 
+INF = float('inf')
+NEG_INF = float('-inf')
+NAN = float('nan')
+
+class NotNum(float, Enum):
+    inf = INF
+    neg_inf = NEG_INF
+    nan = NAN
+
 class TestEnum:
 
     def test_floats(self):
         for enum in FloatNum:
             self.assertEqual(self.dumps(enum), repr(enum.value))
             self.assertEqual(float(self.dumps(enum)), enum)
             self.assertEqual(self.loads(self.dumps(enum)), enum)
 
+    def test_weird_floats(self):
+        for enum, expected in zip(NotNum, ('Infinity', '-Infinity', 'NaN')):
+            self.assertEqual(self.dumps(enum), expected)
+            if not isnan(enum):
+                self.assertEqual(float(self.dumps(enum)), enum)
+                self.assertEqual(self.loads(self.dumps(enum)), enum)
+            else:
+                self.assertTrue(isnan(float(self.dumps(enum))))
+                self.assertTrue(isnan(self.loads(self.dumps(enum))))
+
+
     def test_ints(self):
         for enum in BigNum:
             self.assertEqual(self.dumps(enum), str(enum.value))
             self.assertEqual(int(self.dumps(enum)), enum)
             self.assertEqual(self.loads(self.dumps(enum)), enum)
 
     def test_list(self):
         self.assertEqual(
                 self.dumps(list(BigNum)),
                 str([SMALL, BIG, HUGE, REALLY_HUGE]),
                 )
-        self.assertEqual(self.dumps(list(FloatNum)), str([E, PI, TAU]))
+        self.assertEqual(
+                self.loads(self.dumps(list(BigNum))),
+                list(BigNum),
+                )
+        self.assertEqual(
+                self.dumps(list(FloatNum)),
+                str([E, PI, TAU]),
+                )
+        self.assertEqual(
+                self.loads(self.dumps(list(FloatNum))),
+                list(FloatNum),
+                )
+        self.assertEqual(
+                self.dumps(list(NotNum)),
+                '[Infinity, -Infinity, NaN]',
+                )
+        self.assertEqual(
+                self.loads(self.dumps(list(NotNum)))[:2],
+                list(NotNum)[:2],
+                )
+        self.assertTrue(isnan(self.loads(self.dumps(list(NotNum)))[2]))
 
     def test_dict_keys(self):
         s, b, h, r = BigNum
         e, p, t = FloatNum
+        i, j, n = NotNum
         d = {
             s:'tiny', b:'large', h:'larger', r:'largest',
             e:"Euler's number", p:'pi', t:'tau',
+            i:'Infinity', j:'-Infinity', n:'NaN',
             }
         nd = self.loads(self.dumps(d))
         self.assertEqual(nd[str(SMALL)], 'tiny')
         self.assertEqual(nd[str(BIG)], 'large')
         self.assertEqual(nd[str(HUGE)], 'larger')
         self.assertEqual(nd[str(REALLY_HUGE)], 'largest')
         self.assertEqual(nd[repr(E)], "Euler's number")
         self.assertEqual(nd[repr(PI)], 'pi')
         self.assertEqual(nd[repr(TAU)], 'tau')
+        self.assertEqual(nd['Infinity'], 'Infinity')
+        self.assertEqual(nd['-Infinity'], '-Infinity')
+        self.assertEqual(nd['NaN'], 'NaN')
 
     def test_dict_values(self):
         d = dict(
                 tiny=BigNum.small,
                 large=BigNum.big,
                 larger=BigNum.huge,
                 largest=BigNum.really_huge,
                 e=FloatNum.e,
                 pi=FloatNum.pi,
                 tau=FloatNum.tau,
+                i=NotNum.inf,
+                j=NotNum.neg_inf,
+                n=NotNum.nan,
                 )
         nd = self.loads(self.dumps(d))
         self.assertEqual(nd['tiny'], SMALL)
         self.assertEqual(nd['large'], BIG)
         self.assertEqual(nd['larger'], HUGE)
         self.assertEqual(nd['largest'], REALLY_HUGE)
         self.assertEqual(nd['e'], E)
         self.assertEqual(nd['pi'], PI)
         self.assertEqual(nd['tau'], TAU)
+        self.assertEqual(nd['i'], INF)
+        self.assertEqual(nd['j'], NEG_INF)
+        self.assertTrue(isnan(nd['n']))
 
 class TestPyEnum(TestEnum, PyTest): pass
 class TestCEnum(TestEnum, CTest): pass