Non-constraint interfaces for all constrainable interfaces

webrtc/api/mediaconstraintsinterface_unittest.cc

Index: webrtc/api/mediaconstraintsinterface_unittest.cc
diff --git a/webrtc/api/mediaconstraintsinterface_unittest.cc b/webrtc/api/mediaconstraintsinterface_unittest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..9807ab7231f79d232dbd0110e72fdbd31ac3d126
--- /dev/null
+++ b/webrtc/api/mediaconstraintsinterface_unittest.cc
@@ -0,0 +1,61 @@
+/*
+ *  Copyright 2016 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include "webrtc/api/mediaconstraintsinterface.h"
+
+#include "webrtc/api/test/fakeconstraints.h"
+#include "webrtc/base/gunit.h"
+
+namespace webrtc {
+
+namespace {
+
+bool Matches(const PeerConnectionInterface::RTCConfiguration& a,
+             const PeerConnectionInterface::RTCConfiguration& b) {
+  return a.audio_jitter_buffer_max_packets ==
+             b.audio_jitter_buffer_max_packets &&
+         a.disable_prerenderer_smoothing == b.disable_prerenderer_smoothing;
+}
+
+TEST(MediaConstraintsInterface, CopyConstraintsIntoRtcConfiguration) {
+  FakeConstraints constraints;
+  PeerConnectionInterface::RTCConfiguration old_configuration;
+  PeerConnectionInterface::RTCConfiguration configuration;
+
+  CopyConstraintsIntoRtcConfiguration(&constraints, &configuration);
+  EXPECT_TRUE(Matches(old_configuration, configuration));
+
+  constraints.SetMandatory(MediaConstraintsInterface::kEnableIPv6, "true");
+  CopyConstraintsIntoRtcConfiguration(&constraints, &configuration);
+  EXPECT_EQ(false, configuration.disable_ipv6);
+  constraints.SetMandatory(MediaConstraintsInterface::kEnableIPv6, "false");
+  CopyConstraintsIntoRtcConfiguration(&constraints, &configuration);
+  EXPECT_EQ(true, configuration.disable_ipv6);
+
+  constraints.SetMandatory(MediaConstraintsInterface::kScreencastMinBitrate,
+                           27);
+  CopyConstraintsIntoRtcConfiguration(&constraints, &configuration);
+  EXPECT_TRUE(configuration.screencast_min_bitrate);
+  EXPECT_EQ(27, *(configuration.screencast_min_bitrate));
+
+  // Setting with an empty configuration will overwrite optional<> fields,
+  // but leave other fields alone.

[nisse-webrtc, 2016/03/03 12:09:39]

I don't understand the logic. If no constraint related to dtls_srtp is present,
why is the configuration flag modified? If that's intended, I think it ought to
be explained why, in a comment in the CopyCon... function.

[hta-webrtc, 2016/03/03 12:32:38]

It came out when I wrote the unittest... when I added the fields, I thought
"they will be empty, setting them to empty again in the CopyCon.. won't harm
anything, nothing else writes to them."

Now that I see it from this side, it looks odd. So I chose to document the
behavior. The alternative is to rewrite the functions inside
mediaconstraintsinterface.cc to not overwrite.

+  constraints = FakeConstraints();
+  configuration = old_configuration;
+  configuration.enable_dtls_srtp = rtc::Optional<bool>(true);
+  configuration.audio_jitter_buffer_max_packets = 34;
+  CopyConstraintsIntoRtcConfiguration(&constraints, &configuration);
+  EXPECT_FALSE(configuration.enable_dtls_srtp);
+  EXPECT_EQ(34, configuration.audio_jitter_buffer_max_packets);
+}
+
+}  // namespace
+
+}  // namespace webrtc