Support for AudioContextOptions latencyHint.

third_party/WebKit/Source/modules/webaudio/AudioContextTest.cpp

Index: third_party/WebKit/Source/modules/webaudio/AudioContextTest.cpp
diff --git a/third_party/WebKit/Source/modules/webaudio/AudioContextTest.cpp b/third_party/WebKit/Source/modules/webaudio/AudioContextTest.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..a76bd7beb6c200d93fd7d62602ea9445a5f9a5b9
--- /dev/null
+++ b/third_party/WebKit/Source/modules/webaudio/AudioContextTest.cpp
@@ -0,0 +1,104 @@
+// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "modules/webaudio/AudioContext.h"
+
+#include "core/dom/Document.h"
+#include "core/testing/DummyPageHolder.h"
+#include "platform/testing/TestingPlatformSupport.h"
+#include "public/platform/WebAudioDevice.h"
+#include "public/platform/WebAudioLatencyHint.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace blink {
+
+namespace {
+
+class MockWebAudioDevice : public WebAudioDevice {
+ public:
+  explicit MockWebAudioDevice(double sampleRate, int framesPerBuffer)
+      : m_sampleRate(sampleRate), m_framesPerBuffer(framesPerBuffer) {}
+  ~MockWebAudioDevice() override = default;
+
+  void start() override {}
+  void stop() override {}
+  double sampleRate() override { return m_sampleRate; }
+  int framesPerBuffer() override { return m_framesPerBuffer; }
+
+ private:
+  double m_sampleRate;
+  int m_framesPerBuffer;
+};
+
+class AudioContextTestPlatform : public TestingPlatformSupport {
+ public:
+  WebAudioDevice* createAudioDevice(unsigned numberOfInputChannels,
+                                    unsigned numberOfChannels,
+                                    const WebAudioLatencyHint& latencyHint,
+                                    WebAudioDevice::RenderCallback*,
+                                    const WebString& deviceId,
+                                    const WebSecurityOrigin&) override {
+    double bufferSize = 0;
+    switch (latencyHint.category()) {
+      case WebAudioLatencyHint::kCategoryInteractive:
+        bufferSize = audioHardwareBufferSize();
+        break;
+      case WebAudioLatencyHint::kCategoryBalanced:
+        bufferSize = audioHardwareBufferSize() * 2;
+        break;
+      case WebAudioLatencyHint::kCategoryPlayback:
+        bufferSize = audioHardwareBufferSize() * 4;
+        break;
+      default:
+        NOTREACHED();
+        break;
+    }
+
+    return new MockWebAudioDevice(audioHardwareSampleRate(), bufferSize);
+  }
+
+  double audioHardwareSampleRate() override { return 44100; }
+  size_t audioHardwareBufferSize() override { return 128; }
+};
+
+}  // anonymous namespace
+
+class AudioContextTest : public ::testing::Test {
+ protected:
+  void SetUp() override { m_dummyPageHolder = DummyPageHolder::create(); }
+
+  Document& document() { return m_dummyPageHolder->document(); }
+
+ private:
+  std::unique_ptr<DummyPageHolder> m_dummyPageHolder;
+};
+
+TEST_F(AudioContextTest, AudioContextOptions_WebAudioLatencyHint) {
+  ScopedTestingPlatformSupport<AudioContextTestPlatform> platform;
+
+  AudioContextOptions interactiveOptions;
+  interactiveOptions.setLatencyHint(
+      AudioContextLatencyCategoryOrDouble::fromAudioContextLatencyCategory(
+          "interactive"));
+  AudioContext* interactiveContext =
+      AudioContext::create(document(), interactiveOptions, ASSERT_NO_EXCEPTION);
+
+  AudioContextOptions balancedOptions;
+  balancedOptions.setLatencyHint(
+      AudioContextLatencyCategoryOrDouble::fromAudioContextLatencyCategory(
+          "balanced"));
+  AudioContext* balancedContext =
+      AudioContext::create(document(), balancedOptions, ASSERT_NO_EXCEPTION);
+  EXPECT_GT(balancedContext->baseLatency(), interactiveContext->baseLatency());
+
+  AudioContextOptions playbackOptions;
+  playbackOptions.setLatencyHint(
+      AudioContextLatencyCategoryOrDouble::fromAudioContextLatencyCategory(
+          "playback"));
+  AudioContext* playbackContext =
+      AudioContext::create(document(), playbackOptions, ASSERT_NO_EXCEPTION);
+  EXPECT_GT(playbackContext->baseLatency(), balancedContext->baseLatency());
+}
+
+}  // namespace blink