int inputOffsetField = inputCount > 0 ? payloadStart : 0;
        int outputOffsetField = outputCount > 0 ? payloadStart + inputCount : 0;

        // inputOffset (relative to header start)
        SMBUtil.writeInt4(inputOffsetField, buf, pos);
        pos += 4;
        // inputCount
        SMBUtil.writeInt4(inputCount, buf, pos);
        pos += 4;

        this.outputData = this.outputBuffer == null ? createOutputDecodable() : null;

        if (this.inputData != null) {
            this.inputData.decode(buffer, inputOffset, inputCount);
        }
        bufferIndex = Math.max(inputOffset + inputCount, bufferIndex);

        if (this.outputBuffer != null) {
            if (outputCount > this.outputBuffer.length) {

  @GwtIncompatible // used only in GwtIncompatible tests
  private static void runExtensiveMergerTest(Merger merger) throws InterruptedException {
    int inputCount = new TestFutureBatch().allFutures.size();

    for (int i = 0; i < inputCount; i++) {
      for (int j = 0; j < inputCount; j++) {
        for (boolean iBeforeJ : new boolean[] {true, false}) {
          TestFutureBatch inputs = new TestFutureBatch();

  @GwtIncompatible // used only in GwtIncompatible tests
  private static void runExtensiveMergerTest(Merger merger) throws InterruptedException {
    int inputCount = new TestFutureBatch().allFutures.size();

    for (int i = 0; i < inputCount; i++) {
      for (int j = 0; j < inputCount; j++) {
        for (boolean iBeforeJ : new boolean[] {true, false}) {
          TestFutureBatch inputs = new TestFutureBatch();

      if (localState != null) {
        // Don't print the actual array! We don't want inCompletionOrder(list).toString() to have
        // quadratic output.
        return "inputCount=["
            + localState.inputFutures.length
            + "], remaining=["
            + localState.incompleteOutputCount.get()
            + "]";
      }
      return null;
    }
  }