Function calculateStartDuration

lib/internal/perf/usertiming.js:174–223

(startOrMeasureOptions, endMark)

}

function calculateStartDuration(startOrMeasureOptions, endMark) {
  startOrMeasureOptions ??= 0;
  let start;
  let end;
  let duration;
  let optionsValid = false;
  if (typeof startOrMeasureOptions === 'object') {
    ({ start, end, duration } = startOrMeasureOptions);
    optionsValid = start !== undefined || end !== undefined;
  }
  if (optionsValid) {
    if (endMark !== undefined) {
      throw new ERR_PERFORMANCE_MEASURE_INVALID_OPTIONS(
        'endMark must not be specified');
    }

    if (start === undefined && end === undefined) {
      throw new ERR_PERFORMANCE_MEASURE_INVALID_OPTIONS(
        'One of options.start or options.end is required');
    }
    if (start !== undefined && end !== undefined && duration !== undefined) {
      throw new ERR_PERFORMANCE_MEASURE_INVALID_OPTIONS(
        'Must not have options.start, options.end, and ' +
        'options.duration specified');
    }
  }

  if (endMark !== undefined) {
    end = getMark(endMark);
  } else if (optionsValid && end !== undefined) {
    end = getMark(end);
  } else if (optionsValid && start !== undefined && duration !== undefined) {
    end = getMark(start) + getMark(duration);
  } else {
    end = now();
  }

  if (typeof startOrMeasureOptions === 'string') {
    start = getMark(startOrMeasureOptions);
  } else if (optionsValid && start !== undefined) {
    start = getMark(start);
  } else if (optionsValid && duration !== undefined && end !== undefined) {
    start = end - getMark(duration);
  } else {
    start = 0;
  }

  duration = end - start;
  return { start, duration };
}

function measure(name, startOrMeasureOptions, endMark) {
  validateString(name, 'name');