Keep track of the user-facing number of channels in a ChannelBuffer

webrtc/common_audio/channel_buffer_unittest.cc

+/*
+ *  Copyright (c) 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 "testing/gtest/include/gtest/gtest.h"
+#include "webrtc/common_audio/channel_buffer.h"
+
+namespace webrtc {
+
+namespace {
+
+void ExpectNumChannels(const IFChannelBuffer& ifchb, size_t num_channels) {
+  EXPECT_EQ(ifchb.ibuf_const()->num_channels(), num_channels);
+  EXPECT_EQ(ifchb.fbuf_const()->num_channels(), num_channels);
+  EXPECT_EQ(ifchb.num_channels(), num_channels);
+}
+
+}  // namespace
+

[tlegrand-webrtc, 2016/06/28 13:48:04]

You haven't added any tests where you try to break things, like setting a larger
number of channels than what the Channel was configured for.

[aluebs-webrtc, 2016/06/29 00:48:40]

I don't think there is a way to catch DCHECKs, right?

[aluebs-webrtc, 2016/06/29 23:02:58]

Now I added death tests.

+TEST(ChannelBufferTest, SetNumChannelsSetsNumChannels) {
+  const size_t kNumFrames = 480u;
+  const size_t kStereo = 2u;
+  const size_t kMono = 1u;
+  ChannelBuffer<float> chb(kNumFrames, kStereo);
+  EXPECT_EQ(chb.num_channels(), kStereo);
+  chb.set_num_channels(kMono);
+  EXPECT_EQ(chb.num_channels(), kMono);
+}
+
+TEST(IFChannelBufferTest, SetNumChannelsSetsChannelBuffersNumChannels) {
+  const size_t kNumFrames = 480u;
+  const size_t kStereo = 2u;
+  const size_t kMono = 1u;
+  IFChannelBuffer ifchb(kNumFrames, kStereo);
+  ExpectNumChannels(ifchb, kStereo);
+  ifchb.set_num_channels(kMono);
+  ExpectNumChannels(ifchb, kMono);
+}
+
+TEST(IFChannelBufferTest, SettingNumChannelsOfOneChannelBufferSetsTheOther) {
+  const size_t kNumFrames = 480u;
+  const size_t kStereo = 2u;
+  const size_t kMono = 1u;
+  IFChannelBuffer ifchb(kNumFrames, kStereo);
+  ExpectNumChannels(ifchb, kStereo);
+  ifchb.ibuf()->set_num_channels(kMono);
+  ExpectNumChannels(ifchb, kMono);
+  ifchb.fbuf()->set_num_channels(kStereo);
+  ExpectNumChannels(ifchb, kStereo);
+}
+
+}  // namespace webrtc