Function subscribe

test/parallel/test-diagnostics-channel-web-locks.js:8–20

({ start, grant, miss, end })

const dc = require('node:diagnostics_channel');

function subscribe({ start, grant, miss, end }) {
  if (start) dc.subscribe('locks.request.start', start);
  if (grant) dc.subscribe('locks.request.grant', grant);
  if (miss) dc.subscribe('locks.request.miss', miss);
  if (end) dc.subscribe('locks.request.end', end);

  return () => {
    if (start) dc.unsubscribe('locks.request.start', start);
    if (grant) dc.unsubscribe('locks.request.grant', grant);
    if (miss) dc.unsubscribe('locks.request.miss', miss);
    if (end) dc.unsubscribe('locks.request.end', end);
  };
}

describe('Web Locks diagnostics channel', () => {
  it('emits start, grant, and end on success', async () => {