json.tool: --tab identation option

Author: dhimmel

Lib/json/tool.py

@@ -33,6 +33,8 @@ def main():
                        'pretty-printing. Defaults to 4.')
     group.add_argument('--no-indent', action='store_const', dest='indent',
                        const=None, help='Use compact mode.')
+    group.add_argument('--tab', action='store_const', dest='indent',
+                       const='\t', help='Use tabs for indentation.')
     parser.add_argument('--sort-keys', action='store_true',
                         help='sort the output of dictionaries by key')
     options = parser.parse_args()

Lib/test/test_json/test_tool.py

@@ -128,3 +128,12 @@ def test_no_indent(self):
             json_stdout, err = proc.communicate(json_stdin)
         self.assertEqual(expect.splitlines(), json_stdout.splitlines())
         self.assertEqual(err, b'')
+
+    def test_tab(self):
+        json_stdin = b'[1, 2]'
+        expect = b'[\n\t1,\n\t2\n]\n'
+        args = sys.executable, '-m', 'json.tool', '--tab'
+        with Popen(args, stdin=PIPE, stdout=PIPE, stderr=PIPE) as proc:
+            json_stdout, err = proc.communicate(json_stdin)
+        self.assertEqual(expect.splitlines(), json_stdout.splitlines())
+        self.assertEqual(err, b'')