static filteredTraceSort()

in src/sdk/lh-trace-processor.ts [212:258]
33 lines of code
8 McCabe index (conditional complexity)

  static filteredTraceSort(traceEvents, filter) {
    // create an array of the indices that we want to keep
    const indices = [];
    for (let srcIndex = 0; srcIndex < traceEvents.length; srcIndex++) {
      if (filter(traceEvents[srcIndex])) {
        indices.push(srcIndex);
      }
    }

    // Sort by ascending timestamp first.
    indices.sort(
      (indexA, indexB) => traceEvents[indexA].ts - traceEvents[indexB].ts
    );

    // Now we find groups with equal timestamps and order them by their nesting structure.
    for (let i = 0; i < indices.length - 1; i++) {
      const ts = traceEvents[indices[i]].ts;
      const tsGroupIndices = [i];
      for (let j = i + 1; j < indices.length; j++) {
        if (traceEvents[indices[j]].ts !== ts) break;
        tsGroupIndices.push(j);
      }

      // We didn't find any other events with the same timestamp, just keep going.
      if (tsGroupIndices.length === 1) continue;

      // Sort the group by other criteria and replace our index array with it.
      const finalIndexOrder = TraceProcessor._sortTimestampEventGroup(
        tsGroupIndices,
        indices,
        i,
        traceEvents
      );
      indices.splice(i, finalIndexOrder.length, ...finalIndexOrder);
      // We just sorted this set of identical timestamps, so skip over the rest of the group.
      // -1 because we already have i++.
      i += tsGroupIndices.length - 1;
    }

    // create a new array using the target indices from previous sort step
    const sorted = [];
    for (let i = 0; i < indices.length; i++) {
      sorted.push(traceEvents[indices[i]]);
    }

    return sorted;
  }