#18273: merge with 3.3.

1 files changed, 49 insertions, 0 deletions

diff --git a/Lib/test/test_json/test_dump.py b/Lib/test/test_json/test_dump.py
new file mode 100644
index 0000000..af19258
--- /dev/null
+++ b/Lib/test/test_json/test_dump.py
@@ -0,0 +1,49 @@
+from io import StringIO
+from test.test_json import PyTest, CTest
+
+from test.support import bigmemtest, _1G
+
+class TestDump:
+    def test_dump(self):
+        sio = StringIO()
+        self.json.dump({}, sio)
+        self.assertEqual(sio.getvalue(), '{}')
+
+    def test_dumps(self):
+        self.assertEqual(self.dumps({}), '{}')
+
+    def test_encode_truefalse(self):
+        self.assertEqual(self.dumps(
+                 {True: False, False: True}, sort_keys=True),
+                 '{"false": true, "true": false}')
+        self.assertEqual(self.dumps(
+                {2: 3.0, 4.0: 5, False: 1, 6: True}, sort_keys=True),
+                '{"false": 1, "2": 3.0, "4.0": 5, "6": true}')
+
+    # Issue 16228: Crash on encoding resized list
+    def test_encode_mutated(self):
+        a = [object()] * 10
+        def crasher(obj):
+            del a[-1]
+        self.assertEqual(self.dumps(a, default=crasher),
+                 '[null, null, null, null, null]')
+
+
+class TestPyDump(TestDump, PyTest): pass
+
+class TestCDump(TestDump, CTest):
+
+    # The size requirement here is hopefully over-estimated (actual
+    # memory consumption depending on implementation details, and also
+    # system memory management, since this may allocate a lot of
+    # small objects).
+
+    @bigmemtest(size=_1G, memuse=1)
+    def test_large_list(self, size):
+        N = int(30 * 1024 * 1024 * (size / _1G))
+        l = [1] * N
+        encoded = self.dumps(l)
+        self.assertEqual(len(encoded), N * 3)
+        self.assertEqual(encoded[:1], "[")
+        self.assertEqual(encoded[-2:], "1]")
+        self.assertEqual(encoded[1:-2], "1, " * (N - 1))