1 files changed, 63 insertions, 0 deletions
diff --git a/Lib/test/test_json/test_indent.py b/Lib/test/test_json/test_indent.py
new file mode 100644
index 0000000000..a4d4d20142
--- /dev/null
+++ b/Lib/test/test_json/test_indent.py
@@ -0,0 +1,63 @@
+import textwrap
+from io import StringIO
+from test.test_json import PyTest, CTest
+
+
+class TestIndent:
+    def test_indent(self):
+        h = [['blorpie'], ['whoops'], [], 'd-shtaeou', 'd-nthiouh', 'i-vhbjkhnth',
+             {'nifty': 87}, {'field': 'yes', 'morefield': False} ]
+
+        expect = textwrap.dedent("""\
+        [
+        \t[
+        \t\t"blorpie"
+        \t],
+        \t[
+        \t\t"whoops"
+        \t],
+        \t[],
+        \t"d-shtaeou",
+        \t"d-nthiouh",
+        \t"i-vhbjkhnth",
+        \t{
+        \t\t"nifty": 87
+        \t},
+        \t{
+        \t\t"field": "yes",
+        \t\t"morefield": false
+        \t}
+        ]""")
+
+        d1 = self.dumps(h)
+        d2 = self.dumps(h, indent=2, sort_keys=True, separators=(',', ': '))
+        d3 = self.dumps(h, indent='\t', sort_keys=True, separators=(',', ': '))
+
+        h1 = self.loads(d1)
+        h2 = self.loads(d2)
+        h3 = self.loads(d3)
+
+        self.assertEqual(h1, h)
+        self.assertEqual(h2, h)
+        self.assertEqual(h3, h)
+        self.assertEqual(d2, expect.expandtabs(2))
+        self.assertEqual(d3, expect)
+
+    def test_indent0(self):
+        h = {3: 1}
+        def check(indent, expected):
+            d1 = self.dumps(h, indent=indent)
+            self.assertEqual(d1, expected)
+
+            sio = StringIO()
+            self.json.dump(h, sio, indent=indent)
+            self.assertEqual(sio.getvalue(), expected)
+
+        # indent=0 should emit newlines
+        check(0, '{\n"3": 1\n}')
+        # indent=None is more compact
+        check(None, '{"3": 1}')
+
+
+class TestPyIndent(TestIndent, PyTest): pass
+class TestCIndent(TestIndent, CTest): pass