bug: finally block in async function indicates incorrect missing block coverage

Observed Behavior

The following code:

async function abc() {
  try {
    return 'abc';
  } finally {
    console.log('in finally');
  } // this is a covered line but uncovered branch
}

abc()

Ends up having the following coverage output:

{
          "functionName": "abc",
          "ranges": [
            {
              "startOffset": 0,
              "endOffset": 146,
              "count": 1
            },
            {
              "startOffset": 97,
              "endOffset": 145,
              "count": 0
            }
          ],
          "isBlockCoverage": true
        }
}

This indicates that the following characters were tracked as an uncovered block:

// this is a covered line but uncovered branch\n

Expected behavior

Coverage should be 100% in the above example.

[evocateur]

@bcoe Perfectly fair! Especially considering it’s going into maintenance mode in like, 2 months? So I’ll probably drop v12 before I even finish this wee babby of a tool, lol.

[bcoe]

@xolott would you be able to provide a minimal breaking example, this would help in investigating the underlying cause.