nodejs log locator

log-locator.js

const regex = /([^ ]+) [^(]*\(([^:]+):(\d+)/;

function getLocator() {
  // stack 3
  const { stack } = new Error();
  if (!stack) {
    return null;
  }
  // how far is your stdout? std write is 2 steps away
  const match = stack.split("    at ")?.[3].match(regex);
  if (match) {
    const [, fn, file, line] = match;
    return { file, fn, line };
  }
  return null;
}

function log(level, message, meta) {
  // stack 2
  const locator = getLocator();
  console[level](message, { locator, meta });
}

// stack 1
log("info", "Hello World!");