Bug(lint): variable detected as unused when used as index accessor

[marvinhagemeister]

Steps to reproduce

1. Create file foo.ts with these contents:

export function updateDiffStats(stats, diff, childCount) {
  const idx = getChildCountIdx(childCount);
  if (diff === 1) {
    stats.keyed[idx]++;
  } else if (diff === 2) {
    stats.unkeyed[idx]++;
  } else if (diff === 3) {
    stats.mixed[idx]++;
  }
}

const getChildCountIdx = (n) => n;

2. Run npx oxlint foo.ts

Output:

$ npx oxlint foo.ts

  ⚠ eslint(no-unused-vars): Variable 'idx' is declared but never used.
   ╭─[foo.ts:2:8]
 1 │ export function updateDiffStats(stats, diff, childCount) {
 2 │     const idx = getChildCountIdx(childCount);
   ·           ─┬─
   ·            ╰── 'idx' is declared here
 3 │     if (diff === 1) {
   ╰────
  help: Consider removing this declaration.

Finished in 3ms on 1 file with 94 rules using 10 threads.
Found 1 warning and 0 errors.

[Boshen]

This is already fixed, will release soon!

[camc314]

https://github.com/oxc-project/oxc/pull/5722/files

[marvinhagemeister]

Awesome, closing as resolved by #5722 in this case.