Issue #10572: Moved json tests to Lib/test/json_tests.

Approved by Raymond Hettinger.

Lib/test/json_tests/test_dump.py

@@ -0,0 +1,21 @@
+from unittest import TestCase
+from io import StringIO
+
+import json
+
+class TestDump(TestCase):
+    def test_dump(self):
+        sio = StringIO()
+        json.dump({}, sio)
+        self.assertEqual(sio.getvalue(), '{}')
+
+    def test_dumps(self):
+        self.assertEqual(json.dumps({}), '{}')
+
+    def test_encode_truefalse(self):
+        self.assertEqual(json.dumps(
+                 {True: False, False: True}, sort_keys=True),
+                 '{"false": true, "true": false}')
+        self.assertEqual(json.dumps(
+                {2: 3.0, 4.0: 5, False: 1, 6: True}, sort_keys=True),
+                '{"false": 1, "2": 3.0, "4.0": 5, "6": true}')