processTimelineEvent() — react Function Reference

Source Code

packages/react-devtools-timeline/src/import-worker/preprocessData.js lines 430–805

function processTimelineEvent(
  event: TimelineEvent,
  /** Finalized profiler data up to `event`. May be mutated. */
  currentProfilerData: TimelineData,
  /** Intermediate processor state. May be mutated. */
  state: ProcessorState,
) {
  const {cat, name, ts, ph} = event;

  const startTime = (ts - currentProfilerData.startTime) / 1000;

  switch (cat) {
    case 'disabled-by-default-devtools.screenshot':
      processScreenshot(event, startTime, currentProfilerData, state);
      break;
    case 'devtools.timeline':
      switch (name) {
        case 'EventDispatch':
          processEventDispatch(event, startTime, currentProfilerData, state);
          break;
        case 'ResourceFinish':
          processResourceFinish(event, startTime, currentProfilerData, state);
          break;
        case 'ResourceReceivedData':
          processResourceReceivedData(
            event,
            startTime,
            currentProfilerData,
            state,
          );
          break;
        case 'ResourceReceiveResponse':
          processResourceReceiveResponse(
            event,
            startTime,
            currentProfilerData,
            state,
          );
          break;
        case 'ResourceSendRequest':
          processResourceSendRequest(
            event,
            startTime,
            currentProfilerData,
            state,
          );
          break;
      }
      break;
    case 'blink.user_timing':
      if (name.startsWith('--react-version-')) {
        const [reactVersion] = name.slice(16).split('-');
        currentProfilerData.reactVersion = reactVersion;
      } else if (name.startsWith('--profiler-version-')) {
        const [versionString] = name.slice(19).split('-');
        profilerVersion = parseInt(versionString, 10);
        if (profilerVersion !== SCHEDULING_PROFILER_VERSION) {
          throw new InvalidProfileError(
            `This version of profiling data (${versionString}) is not supported by the current profiler.`,
          );
        }
      } else if (name.startsWith('--react-lane-labels-')) {
        const [laneLabelTuplesString] = name.slice(20).split('-');
        updateLaneToLabelMap(currentProfilerData, laneLabelTuplesString);
      } else if (name.startsWith('--component-')) {
        processReactComponentMeasure(
          name,
          startTime,
          currentProfilerData,
          state,
        );
      } else if (name.startsWith('--schedule-render-')) {
        const [laneBitmaskString] = name.slice(18).split('-');

        currentProfilerData.schedulingEvents.push({
          type: 'schedule-render',
          lanes: getLanesFromTransportDecimalBitmask(laneBitmaskString),
          timestamp: startTime,
          warning: null,
        });
      } else if (name.startsWith('--schedule-forced-update-')) {