static computeValidLCPAllFrames()

in src/sdk/lh-trace-processor.ts [602:634]

• 24 lines of code
• 9 McCabe index (conditional complexity)

  static computeValidLCPAllFrames(events, timeOriginEvent) {
    const lcpEvents = events.filter(this.isLCPEvent).reverse();

    /** @type {Map<string, LCPEvent>} */
    const finalLcpEventsByFrame = new Map();
    for (const e of lcpEvents) {
      if (e.ts <= timeOriginEvent.ts) break;

      // Already found final LCP state of this frame.
      const frame = e.args.frame;
      if (finalLcpEventsByFrame.has(frame)) continue;

      finalLcpEventsByFrame.set(frame, e);
    }

    /** @type {LCPCandidateEvent | undefined} */
    let maxLcpAcrossFrames;
    for (const lcp of finalLcpEventsByFrame.values()) {
      if (!this.isLCPCandidateEvent(lcp)) continue;
      if (
        !maxLcpAcrossFrames ||
        lcp.args.data.size > maxLcpAcrossFrames.args.data.size
      ) {
        maxLcpAcrossFrames = lcp;
      }
    }

    return {
      lcp: maxLcpAcrossFrames,
      // LCP events were found, but final LCP event of every frame was an invalidate event.
      invalidated: Boolean(!maxLcpAcrossFrames && finalLcpEventsByFrame.size),
    };
  }