Auto merge of #12301 - ConnorGBrewster:selection_direction, r=asajeffrey

Take selection direction into account when setting selection

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r? @asajeffrey

---
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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 #12300 (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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tests/unit/script/textinput.rs

@@ -458,3 +458,26 @@ fn test_textinput_cursor_position_correct_after_clearing_selection() {
     assert_eq!(textinput.edit_point.index, 0);
     assert_eq!(textinput.edit_point.line, 0);
 }
+
+
+#[test]
+fn test_textinput_set_selection_with_direction() {
+    let mut textinput = text_input(Lines::Single, "abcdef");
+    textinput.selection_direction = SelectionDirection::Forward;
+    textinput.set_selection_range(2, 6);
+    assert_eq!(textinput.edit_point.line, 0);
+    assert_eq!(textinput.edit_point.index, 6);
+
+    assert!(textinput.selection_begin.is_some());
+    assert_eq!(textinput.selection_begin.unwrap().line, 0);
+    assert_eq!(textinput.selection_begin.unwrap().index, 2);
+
+    textinput.selection_direction = SelectionDirection::Backward;
+    textinput.set_selection_range(2, 6);
+    assert_eq!(textinput.edit_point.line, 0);
+    assert_eq!(textinput.edit_point.index, 2);
+
+    assert!(textinput.selection_begin.is_some());
+    assert_eq!(textinput.selection_begin.unwrap().line, 0);
+    assert_eq!(textinput.selection_begin.unwrap().index, 6);
+}