Diagnostics and semantic tokens get incorrectly highlighted after doing some specific actions in a line

[blaumeise20]

Does this issue occur when all extensions are disabled?: Yes

• VS Code Version: 1.81.1
• OS Version: Windows 11 (10.0.22621)

Steps to Reproduce:

1. Make a new file and set the language to JavaScript or TypeScript.
2. Paste this code:

   function bug(
       test // true = test test 123
   ) {}

3. Put your cursor next to the second slash of the comment.
4. Press backspace.
5. Type * twice. (This will automatically extend to /**| */ as JSDoc comments are marked as auto closing pairs)
6. Move your cursor three characters to the right using the arrow keys (It should be after the closing slash).
7. Press backspace three times.
   Your code should now look like this:

   function bug(
       test /**| true = test test 123
   ) {}

   Where | is the cursor position.
8. Now press End (Windows) or Cmd+RightArrow (Mac) to go to the end of the line.
9. Type */.
10. Enjoy the bug ;-)

If anyone can't reproduce it, this is the outcome for me:

[alexdima]

@blaumeise20 Appologies for the slow reaction. Thank you for the very good repro steps!

@mjbvz I can totally reproduce and I see a lot of errors coming in from the ts server:

 ERR <syntax> TypeScript Server Error (5.2.2)
Debug Failure. False expression.
Error: Debug Failure. False expression.
    at Object.updateSourceFile2
...

[sheetalkamat]

Testcase for the root cause is incremental parser going off the rails:

 it("when comment is completed", () => {
        const source = "function bug(\r\n    test /** */ true = test test 123\r\n) {}";
        const oldText = ts.ScriptSnapshot.fromString(source);
        const index = source.indexOf("/");
        const newTextAndChange = withChange(oldText, index, 1, "");

        compareTrees(oldText, newTextAndChange.text, newTextAndChange.textChangeRange, 0);
    });