Auto merge of #15822 - charlesvdv:unicode-panic, r=emilio

Correct unicode handling for text input

<!-- Please describe your changes on the following line: -->
Allow proprer handling of unicode sequence in text input.

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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 #15819

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

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1 files changed, 10 insertions, 0 deletions

diff --git a/tests/unit/script/textinput.rs b/tests/unit/script/textinput.rs
index a9e5a9fc08b..620368b4d8f 100644
--- a/tests/unit/script/textinput.rs
+++ b/tests/unit/script/textinput.rs
@@ -602,3 +602,13 @@ fn test_textinput_set_selection_with_direction() {
     assert_eq!(textinput.selection_begin.unwrap().line, 0);
     assert_eq!(textinput.selection_begin.unwrap().index, 6);
 }
+
+#[test]
+fn test_textinput_unicode_handling() {
+    let mut textinput = text_input(Lines::Single, "éèùµ$£");
+    assert_eq!(textinput.edit_point.index, 0);
+    textinput.set_edit_point_index(1);
+    assert_eq!(textinput.edit_point.index, 2);
+    textinput.set_edit_point_index(4);
+    assert_eq!(textinput.edit_point.index, 8);
+}