Auto merge of #11190 - mrmiywj:Root-tidy-checker, r=jdm

add &Root<T> checker

Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `__` with appropriate data:
- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #11137  (github issue number if applicable).

Either:
- [X] There are tests for these changes OR
- [ ] These changes do not require tests because _____

Pull requests that do not address these steps are welcome, but they will require additional verification as part of the review process.

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2 files changed, 2 insertions, 1 deletions

diff --git a/python/tidy/servo_tidy_tests/rust_tidy.rs b/python/tidy/servo_tidy_tests/rust_tidy.rs
index ef0a53b4b24..bf6437f806d 100644
--- a/python/tidy/servo_tidy_tests/rust_tidy.rs
+++ b/python/tidy/servo_tidy_tests/rust_tidy.rs
@@ -36,7 +36,7 @@ impl test {
         }
     }
 
-    fn test_fun2(y : &String, z : &Vec<f32>) -> f32 {
+    fn test_fun2(y : &String, z : &Vec<f32>, r: &Root<isize>) -> f32 {
         let x = true;
         x
             && x;
diff --git a/python/tidy/servo_tidy_tests/test_tidy.py b/python/tidy/servo_tidy_tests/test_tidy.py
index c9291c1c2f2..a50532fbade 100644
--- a/python/tidy/servo_tidy_tests/test_tidy.py
+++ b/python/tidy/servo_tidy_tests/test_tidy.py
@@ -74,6 +74,7 @@ class CheckTidiness(unittest.TestCase):
         self.assertEqual('extra space before :', errors.next()[2])
         self.assertEqual('use &[T] instead of &Vec<T>', errors.next()[2])
         self.assertEqual('use &str instead of &String', errors.next()[2])
+        self.assertEqual('use &T instead of &Root<T>', errors.next()[2])
         self.assertEqual('operators should go at the end of the first line', errors.next()[2])
         self.assertNoMoreErrors(errors)