| Index: webrtc/modules/audio_processing/aec3/output_selector_unittest.cc
 | 
| diff --git a/webrtc/modules/audio_processing/aec3/output_selector_unittest.cc b/webrtc/modules/audio_processing/aec3/output_selector_unittest.cc
 | 
| new file mode 100644
 | 
| index 0000000000000000000000000000000000000000..49f671d2b1edd6fc485856d32089777be9d0b580
 | 
| --- /dev/null
 | 
| +++ b/webrtc/modules/audio_processing/aec3/output_selector_unittest.cc
 | 
| @@ -0,0 +1,71 @@
 | 
| +/*
 | 
| + *  Copyright (c) 2017 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/modules/audio_processing/aec3/output_selector.h"
 | 
| +
 | 
| +#include <algorithm>
 | 
| +#include <array>
 | 
| +
 | 
| +#include "webrtc/modules/audio_processing/aec3/aec3_common.h"
 | 
| +#include "webrtc/test/gtest.h"
 | 
| +
 | 
| +namespace webrtc {
 | 
| +
 | 
| +// Verifies that the switching between the signals in the output works as
 | 
| +// intended.
 | 
| +TEST(OutputSelector, ProperSwitching) {
 | 
| +  OutputSelector selector;
 | 
| +
 | 
| +  constexpr int kNumBlocksToSwitchToSubtractor = 3;
 | 
| +  constexpr int kNumBlocksToSwitchFromSubtractor = 10;
 | 
| +
 | 
| +  std::array<float, kBlockSize> weaker;
 | 
| +  std::array<float, kBlockSize> stronger;
 | 
| +  std::array<float, kBlockSize> y;
 | 
| +  std::array<float, kBlockSize> e;
 | 
| +  weaker.fill(10.f);
 | 
| +  stronger.fill(20.f);
 | 
| +
 | 
| +  bool y_is_weakest = false;
 | 
| +
 | 
| +  const auto form_e_and_y = [&](bool y_equals_weaker) {
 | 
| +    if (y_equals_weaker) {
 | 
| +      std::copy(weaker.begin(), weaker.end(), y.begin());
 | 
| +      std::copy(stronger.begin(), stronger.end(), e.begin());
 | 
| +    } else {
 | 
| +      std::copy(stronger.begin(), stronger.end(), y.begin());
 | 
| +      std::copy(weaker.begin(), weaker.end(), e.begin());
 | 
| +    }
 | 
| +  };
 | 
| +
 | 
| +  for (int k = 0; k < 30; ++k) {
 | 
| +    // Verify that it takes a while for the signals transition to take effect.
 | 
| +    const int num_blocks_to_switch = y_is_weakest
 | 
| +                                         ? kNumBlocksToSwitchFromSubtractor
 | 
| +                                         : kNumBlocksToSwitchToSubtractor;
 | 
| +    for (int j = 0; j < num_blocks_to_switch; ++j) {
 | 
| +      form_e_and_y(y_is_weakest);
 | 
| +      selector.FormLinearOutput(e, y);
 | 
| +      EXPECT_EQ(stronger, y);
 | 
| +      EXPECT_EQ(y_is_weakest, selector.UseSubtractorOutput());
 | 
| +    }
 | 
| +
 | 
| +    // Verify that the transition block is a mix between the signals.
 | 
| +    form_e_and_y(y_is_weakest);
 | 
| +    selector.FormLinearOutput(e, y);
 | 
| +    EXPECT_NE(weaker, y);
 | 
| +    EXPECT_NE(stronger, y);
 | 
| +    EXPECT_EQ(!y_is_weakest, selector.UseSubtractorOutput());
 | 
| +
 | 
| +    y_is_weakest = !y_is_weakest;
 | 
| +  }
 | 
| +}
 | 
| +
 | 
| +}  // namespace webrtc
 | 
| 
 |