What can't loopback test be more like full stack test?

webrtc/video/video_loopback.cc

Index: webrtc/video/video_loopback.cc
diff --git a/webrtc/video/video_loopback.cc b/webrtc/video/video_loopback.cc
index 6c2a1630fda8c1c4c16f63f56cbb4d7f6cb5fd1f..66bafbb6f00165bb0c894ec1d6f05a216ca746d3 100644
--- a/webrtc/video/video_loopback.cc
+++ b/webrtc/video/video_loopback.cc
@@ -10,7 +10,7 @@
 
 #include <stdio.h>
 
-#include "gflags/gflags.h"
+#include "webrtc/base/flags.h"
 #include "webrtc/test/field_trial.h"
 #include "webrtc/test/gtest.h"
 #include "webrtc/test/run_test.h"
@@ -20,171 +20,177 @@ namespace webrtc {
 namespace flags {
 
 // Flags common with screenshare loopback, with different default values.
-DEFINE_int32(width, 640, "Video width.");
+DEFINE_int(width, 640, "Video width.");
 size_t Width() {
-  return static_cast<size_t>(FLAGS_width);
+  return static_cast<size_t>(FLAG_width);
 }
 
-DEFINE_int32(height, 480, "Video height.");
+DEFINE_int(height, 480, "Video height.");
 size_t Height() {
-  return static_cast<size_t>(FLAGS_height);
+  return static_cast<size_t>(FLAG_height);
 }
 
-DEFINE_int32(fps, 30, "Frames per second.");
+DEFINE_int(fps, 30, "Frames per second.");
 int Fps() {
-  return static_cast<int>(FLAGS_fps);
+  return static_cast<int>(FLAG_fps);
 }
 
-DEFINE_int32(capture_device_index, 0, "Capture device to select");
+DEFINE_int(capture_device_index, 0, "Capture device to select");
 size_t GetCaptureDevice() {
-  return static_cast<size_t>(FLAGS_capture_device_index);
+  return static_cast<size_t>(FLAG_capture_device_index);
 }
 
-DEFINE_int32(min_bitrate, 50, "Call and stream min bitrate in kbps.");
+DEFINE_int(min_bitrate, 50, "Call and stream min bitrate in kbps.");
 int MinBitrateKbps() {
-  return static_cast<int>(FLAGS_min_bitrate);
+  return static_cast<int>(FLAG_min_bitrate);
 }
 
-DEFINE_int32(start_bitrate, 300, "Call start bitrate in kbps.");
+DEFINE_int(start_bitrate, 300, "Call start bitrate in kbps.");
 int StartBitrateKbps() {
-  return static_cast<int>(FLAGS_start_bitrate);
+  return static_cast<int>(FLAG_start_bitrate);
 }
 
-DEFINE_int32(target_bitrate, 800, "Stream target bitrate in kbps.");
+DEFINE_int(target_bitrate, 800, "Stream target bitrate in kbps.");
 int TargetBitrateKbps() {
-  return static_cast<int>(FLAGS_target_bitrate);
+  return static_cast<int>(FLAG_target_bitrate);
 }
 
-DEFINE_int32(max_bitrate, 800, "Call and stream max bitrate in kbps.");
+DEFINE_int(max_bitrate, 800, "Call and stream max bitrate in kbps.");
 int MaxBitrateKbps() {
-  return static_cast<int>(FLAGS_max_bitrate);
+  return static_cast<int>(FLAG_max_bitrate);
 }
 
 DEFINE_bool(suspend_below_min_bitrate,
             false,
             "Suspends video below the configured min bitrate.");
 
-DEFINE_int32(num_temporal_layers,
-             1,
-             "Number of temporal layers. Set to 1-4 to override.");
+DEFINE_int(num_temporal_layers,
+           1,
+           "Number of temporal layers. Set to 1-4 to override.");
 int NumTemporalLayers() {
-  return static_cast<int>(FLAGS_num_temporal_layers);
+  return static_cast<int>(FLAG_num_temporal_layers);
 }
 
 // Flags common with screenshare loopback, with equal default values.
 DEFINE_string(codec, "VP8", "Video codec to use.");
 std::string Codec() {
-  return static_cast<std::string>(FLAGS_codec);
+  return static_cast<std::string>(FLAG_codec);
 }
 
-DEFINE_int32(selected_tl,
-             -1,
-             "Temporal layer to show or analyze. -1 to disable filtering.");
+DEFINE_int(selected_tl,
+           -1,
+           "Temporal layer to show or analyze. -1 to disable filtering.");
 int SelectedTL() {
-  return static_cast<int>(FLAGS_selected_tl);
+  return static_cast<int>(FLAG_selected_tl);
 }
 
-DEFINE_int32(
+DEFINE_int(
     duration,
     0,
     "Duration of the test in seconds. If 0, rendered will be shown instead.");
 int DurationSecs() {
-  return static_cast<int>(FLAGS_duration);
+  return static_cast<int>(FLAG_duration);
 }
 
 DEFINE_string(output_filename, "", "Target graph data filename.");
 std::string OutputFilename() {
-  return static_cast<std::string>(FLAGS_output_filename);
+  return static_cast<std::string>(FLAG_output_filename);
 }
 
 DEFINE_string(graph_title,
               "",
               "If empty, title will be generated automatically.");
 std::string GraphTitle() {
-  return static_cast<std::string>(FLAGS_graph_title);
+  return static_cast<std::string>(FLAG_graph_title);
 }
 
-DEFINE_int32(loss_percent, 0, "Percentage of packets randomly lost.");
+DEFINE_int(loss_percent, 0, "Percentage of packets randomly lost.");
 int LossPercent() {
-  return static_cast<int>(FLAGS_loss_percent);
+  return static_cast<int>(FLAG_loss_percent);
 }
 
-DEFINE_int32(avg_burst_loss_length,
-             -1,
-             "Average burst length of lost packets.");
+DEFINE_int(avg_burst_loss_length, -1, "Average burst length of lost packets.");
 int AvgBurstLossLength() {
-  return static_cast<int>(FLAGS_avg_burst_loss_length);
+  return static_cast<int>(FLAG_avg_burst_loss_length);
 }
 
-DEFINE_int32(link_capacity,
-             0,
-             "Capacity (kbps) of the fake link. 0 means infinite.");
+DEFINE_int(link_capacity,
+           0,
+           "Capacity (kbps) of the fake link. 0 means infinite.");
 int LinkCapacityKbps() {
-  return static_cast<int>(FLAGS_link_capacity);
+  return static_cast<int>(FLAG_link_capacity);
 }
 
-DEFINE_int32(queue_size, 0, "Size of the bottleneck link queue in packets.");
+DEFINE_int(queue_size, 0, "Size of the bottleneck link queue in packets.");
 int QueueSize() {
-  return static_cast<int>(FLAGS_queue_size);
+  return static_cast<int>(FLAG_queue_size);
 }
 
-DEFINE_int32(avg_propagation_delay_ms,
-             0,
-             "Average link propagation delay in ms.");
+DEFINE_int(avg_propagation_delay_ms,
+           0,
+           "Average link propagation delay in ms.");
 int AvgPropagationDelayMs() {
-  return static_cast<int>(FLAGS_avg_propagation_delay_ms);
+  return static_cast<int>(FLAG_avg_propagation_delay_ms);
 }
 
-DEFINE_int32(std_propagation_delay_ms,
-             0,
-             "Link propagation delay standard deviation in ms.");
+DEFINE_int(std_propagation_delay_ms,
+           0,
+           "Link propagation delay standard deviation in ms.");
 int StdPropagationDelayMs() {
-  return static_cast<int>(FLAGS_std_propagation_delay_ms);
+  return static_cast<int>(FLAG_std_propagation_delay_ms);
 }
 
-DEFINE_int32(selected_stream, 0, "ID of the stream to show or analyze.");
+DEFINE_int(num_streams, 0, "Number of streams to show or analyze.");
+int NumStreams() {
+  return static_cast<int>(FLAG_num_streams);
+}
+
+DEFINE_int(selected_stream,
+           0,
+           "ID of the stream to show or analyze. "
+           "Set to the number of streams to show them all.");
 int SelectedStream() {
-  return static_cast<int>(FLAGS_selected_stream);
+  return static_cast<int>(FLAG_selected_stream);
 }
 
-DEFINE_int32(num_spatial_layers, 1, "Number of spatial layers to use.");
+DEFINE_int(num_spatial_layers, 1, "Number of spatial layers to use.");
 int NumSpatialLayers() {
-  return static_cast<int>(FLAGS_num_spatial_layers);
+  return static_cast<int>(FLAG_num_spatial_layers);
 }
 
-DEFINE_int32(selected_sl,
-             -1,
-             "Spatial layer to show or analyze. -1 to disable filtering.");
+DEFINE_int(selected_sl,
+           -1,
+           "Spatial layer to show or analyze. -1 to disable filtering.");
 int SelectedSL() {
-  return static_cast<int>(FLAGS_selected_sl);
+  return static_cast<int>(FLAG_selected_sl);
 }
 
 DEFINE_string(stream0,
               "",
               "Comma separated values describing VideoStream for stream #0.");
 std::string Stream0() {
-  return static_cast<std::string>(FLAGS_stream0);
+  return static_cast<std::string>(FLAG_stream0);
 }
 
 DEFINE_string(stream1,
               "",
               "Comma separated values describing VideoStream for stream #1.");
 std::string Stream1() {
-  return static_cast<std::string>(FLAGS_stream1);
+  return static_cast<std::string>(FLAG_stream1);
 }
 
 DEFINE_string(sl0,
               "",
               "Comma separated values describing SpatialLayer for layer #0.");
 std::string SL0() {
-  return static_cast<std::string>(FLAGS_sl0);
+  return static_cast<std::string>(FLAG_sl0);
 }
 
 DEFINE_string(sl1,
               "",
               "Comma separated values describing SpatialLayer for layer #1.");
 std::string SL1() {
-  return static_cast<std::string>(FLAGS_sl1);
+  return static_cast<std::string>(FLAG_sl1);
 }
 
 DEFINE_string(encoded_frame_path,
@@ -192,7 +198,7 @@ DEFINE_string(encoded_frame_path,
               "The base path for encoded frame logs. Created files will have "
               "the form <encoded_frame_path>.<n>.(recv|send.<m>).ivf");
 std::string EncodedFramePath() {
-  return static_cast<std::string>(FLAGS_encoded_frame_path);
+  return static_cast<std::string>(FLAG_encoded_frame_path);
 }
 
 DEFINE_bool(logs, false, "print logs to stderr");
@@ -227,9 +233,11 @@ DEFINE_string(clip,
               "",
               "Name of the clip to show. If empty, using chroma generator.");
 std::string Clip() {
-  return static_cast<std::string>(FLAGS_clip);
+  return static_cast<std::string>(FLAG_clip);
 }
 
+DEFINE_bool(help, false, "prints this message");
+
 }  // namespace flags
 
 void Loopback() {
@@ -240,7 +248,7 @@ void Loopback() {
   pipe_config.queue_length_packets = flags::QueueSize();
   pipe_config.queue_delay_ms = flags::AvgPropagationDelayMs();
   pipe_config.delay_standard_deviation_ms = flags::StdPropagationDelayMs();
-  pipe_config.allow_reordering = flags::FLAGS_allow_reordering;
+  pipe_config.allow_reordering = flags::FLAG_allow_reordering;
 
   Call::Config::BitrateConfig call_bitrate_config;
   call_bitrate_config.min_bitrate_bps = flags::MinBitrateKbps() * 1000;
@@ -248,31 +256,36 @@ void Loopback() {
   call_bitrate_config.max_bitrate_bps = flags::MaxBitrateKbps() * 1000;
 
   VideoQualityTest::Params params;
-  params.call = {flags::FLAGS_send_side_bwe, call_bitrate_config};
-  params.video = {flags::FLAGS_video,
+  params.call = {flags::FLAG_send_side_bwe, call_bitrate_config};
+  params.video = {flags::FLAG_video,
                   flags::Width(),
                   flags::Height(),
                   flags::Fps(),
                   flags::MinBitrateKbps() * 1000,
                   flags::TargetBitrateKbps() * 1000,
                   flags::MaxBitrateKbps() * 1000,
-                  flags::FLAGS_suspend_below_min_bitrate,
+                  flags::FLAG_suspend_below_min_bitrate,
                   flags::Codec(),
                   flags::NumTemporalLayers(),
                   flags::SelectedTL(),
                   0,  // No min transmit bitrate.
-                  flags::FLAGS_use_ulpfec,
-                  flags::FLAGS_use_flexfec,
+                  flags::FLAG_use_ulpfec,
+                  flags::FLAG_use_flexfec,
                   flags::EncodedFramePath(),
                   flags::Clip(),
                   flags::GetCaptureDevice()};
-  params.audio = {flags::FLAGS_audio, flags::FLAGS_audio_video_sync,
-      flags::FLAGS_audio_dtx};
+  params.audio = {flags::FLAG_audio, flags::FLAG_audio_video_sync,
+                  flags::FLAG_audio_dtx};
   params.screenshare.enabled = false;
   params.analyzer = {"video", 0.0, 0.0, flags::DurationSecs(),
       flags::OutputFilename(), flags::GraphTitle()};
   params.pipe = pipe_config;
-  params.logs = flags::FLAGS_logs;
+  params.logs = flags::FLAG_logs;
+
+  if (flags::NumStreams() > 1 && flags::Stream0().empty() &&
+      flags::Stream1().empty()) {
+    params.ss.infer_streams = true;
+  }
 
   std::vector<std::string> stream_descriptors;
   stream_descriptors.push_back(flags::Stream0());
@@ -281,7 +294,7 @@ void Loopback() {
   SL_descriptors.push_back(flags::SL0());
   SL_descriptors.push_back(flags::SL1());
   VideoQualityTest::FillScalabilitySettings(
-      &params, stream_descriptors, flags::SelectedStream(),
+      &params, stream_descriptors, flags::NumStreams(), flags::SelectedStream(),
       flags::NumSpatialLayers(), flags::SelectedSL(), SL_descriptors);
 
   VideoQualityTest test;
@@ -295,9 +308,16 @@ void Loopback() {
 
 int main(int argc, char* argv[]) {
   ::testing::InitGoogleTest(&argc, argv);
-  google::ParseCommandLineFlags(&argc, &argv, true);
-  webrtc::test::InitFieldTrialsFromString(
-      webrtc::flags::FLAGS_force_fieldtrials);
+  rtc::FlagList::SetFlagsFromCommandLine(&argc, argv, true);
+  if (webrtc::flags::FLAG_help) {
+    rtc::FlagList::Print(nullptr, false);
+    return 0;
+  }
+
+  // InitFieldTrialsFromString needs a reference to an std::string instance,
+  // with a scope that outlives the test.
+  std::string field_trials = webrtc::flags::FLAG_force_fieldtrials;
+  webrtc::test::InitFieldTrialsFromString(field_trials);
   webrtc::test::RunTest(webrtc::Loopback);
   return 0;
 }