[tidy] check for duplicate keys in .json files

2 files changed, 12 insertions, 0 deletions

diff --git a/python/tidy/servo_tidy_tests/duplicate_key.json b/python/tidy/servo_tidy_tests/duplicate_key.json
new file mode 100644
index 00000000000..6998c789ac9
--- /dev/null
+++ b/python/tidy/servo_tidy_tests/duplicate_key.json
@@ -0,0 +1,7 @@
+{
+    "key": "value",
+    "other_key": {
+        "the_duplicated_key": 1,
+        "the_duplicated_key": 2
+    }
+}
diff --git a/python/tidy/servo_tidy_tests/test_tidy.py b/python/tidy/servo_tidy_tests/test_tidy.py
index 096fb5676b2..8db19a5efd7 100644
--- a/python/tidy/servo_tidy_tests/test_tidy.py
+++ b/python/tidy/servo_tidy_tests/test_tidy.py
@@ -109,6 +109,11 @@ class CheckTidiness(unittest.TestCase):
         self.assertEqual('Invalid control character at: line 3 column 40 (char 61)', errors.next()[2])
         self.assertNoMoreErrors(errors)
 
+    def test_json_with_duplicate_key(self):
+        errors = tidy.collect_errors_for_files(iterFile('duplicate_key.json'), [tidy.check_json], [], print_text=False)
+        self.assertEqual('Duplicated Key (the_duplicated_key)', errors.next()[2])
+        self.assertNoMoreErrors(errors)
+
     def test_lock(self):
         errors = tidy.collect_errors_for_files(iterFile('duplicated_package.lock'), [tidy.check_lock], [], print_text=False)
         msg = """duplicate versions for package "test"