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, 28 insertions, 0 deletions

diff --git a/python/tidy/servo_tidy_tests/multiline_string.rs b/python/tidy/servo_tidy_tests/multiline_string.rs
new file mode 100644
index 00000000000..06f7fda7a96
--- /dev/null
+++ b/python/tidy/servo_tidy_tests/multiline_string.rs
@@ -0,0 +1,28 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+
+// This puts a "multi-line string
+// inside of a comment" and then subsequently has a hyphenated-phrase
+
+
+const FOO: &'static str = "Do not confuse 'apostrophes',
+    They can be 'lifetimes' or 'characters'";
+
+
+fn main() {
+    assert!(foo("test
+                 foo-bar"));
+
+    assert!(foo("test
+                 test2 \"
+                 foo-bar"));
+
+    assert!(foo("test
+                 test2 \
+                 foo-bar"));
+
+    println!("This is a multiline string with a URL, which kinda, \
+             sorta looks like a comment https://github.com/servo/servo/");
+}