Auto merge of #18553 - mdboom:tidy-support-multiline-strings, r=wafflespeanut

Make tidy aware of Rust multiline strings

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This makes the internal tidy script properly ignore the contents of Rust multiline strings.

---
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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #18551 (github issue number if applicable).

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

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1 files changed, 5 insertions, 0 deletions

diff --git a/python/tidy/servo_tidy_tests/test_tidy.py b/python/tidy/servo_tidy_tests/test_tidy.py
index 73a37cd4612..4631d20ded7 100644
--- a/python/tidy/servo_tidy_tests/test_tidy.py
+++ b/python/tidy/servo_tidy_tests/test_tidy.py
@@ -266,6 +266,11 @@ class CheckTidiness(unittest.TestCase):
         lst = list(file_list)
         self.assertEqual([os.path.join(base_path, 'whee', 'test.rs')], lst)
 
+    def test_multiline_string(self):
+        errors = tidy.collect_errors_for_files(iterFile('multiline_string.rs'), [], [tidy.check_rust], print_text=True)
+        self.assertNoMoreErrors(errors)
+
+
 def do_tests():
     suite = unittest.TestLoader().loadTestsFromTestCase(CheckTidiness)
     return 0 if unittest.TextTestRunner(verbosity=2).run(suite).wasSuccessful() else 1