Refactor FFmpegDemuxerTest to use gmock and eliminate flakiness.

media/base/mock_ffmpeg.h

Index: media/base/mock_ffmpeg.h
diff --git a/media/base/mock_ffmpeg.h b/media/base/mock_ffmpeg.h
index 711cf1520605344510fd50a890469e79a56334f7..597898e0b739a76ba162735dd43852f7936f70c3 100644
--- a/media/base/mock_ffmpeg.h
+++ b/media/base/mock_ffmpeg.h
@@ -7,25 +7,101 @@
 
 // TODO(scherkus): See if we can remove ffmpeg_common from this file.
 #include "media/filters/ffmpeg_common.h"
-
 #include "testing/gmock/include/gmock/gmock.h"
 
 namespace media {
 
 class MockFFmpeg {
  public:
+  MockFFmpeg();
+  ~MockFFmpeg();
+
   MOCK_METHOD1(AVCodecFindDecoder, AVCodec*(enum CodecID id));
   MOCK_METHOD2(AVCodecOpen, int(AVCodecContext* avctx, AVCodec* codec));
   MOCK_METHOD2(AVCodecThreadInit, int(AVCodecContext* avctx, int threads));
 
+  MOCK_METHOD5(AVOpenInputFile, int(AVFormatContext** format,
+                                    const char* filename,
+                                    AVInputFormat* input_format,
+                                    int buffer_size,
+                                    AVFormatParameters* parameters));
+  MOCK_METHOD1(AVFindStreamInfo, int(AVFormatContext* format));
+  MOCK_METHOD2(AVReadFrame, int(AVFormatContext* format, AVPacket* packet));
+  MOCK_METHOD4(AVSeekFrame, int(AVFormatContext *format,
+                                int stream_index,
+                                int64_t timestamp,
+                                int flags));
+
+  MOCK_METHOD2(AVNewPacket, int(AVPacket* packet, int size));
+  MOCK_METHOD1(AVFree, void(void* ptr));
+  MOCK_METHOD1(AVFreePacket, void(AVPacket* packet));
+
+  // Used for verifying check points during tests.
+  MOCK_METHOD1(CheckPoint, void(int id));
+
   // Setter/getter for the global instance of MockFFmpeg.
   static void set(MockFFmpeg* instance);
   static MockFFmpeg* get();
 
+  // AVPacket destructor for packets allocated by av_new_packet().
+  static void DestructPacket(AVPacket* packet);
+
+  // Modifies the number of outstanding packets.
+  void inc_outstanding_packets();
+  void dec_outstanding_packets();
+
  private:
   static MockFFmpeg* instance_;
+
+  // Tracks the number of packets allocated by calls to av_read_frame() and
+  // av_free_packet().  We crash the unit test if this is not zero at time of
+  // destruction.
+  int outstanding_packets_;
 };
 
+// Used for simulating av_read_frame().
+ACTION_P3(CreatePacket, stream_index, data, size) {
+  // Confirm we're dealing with AVPacket so we can safely const_cast<>.
+  ::testing::StaticAssertTypeEq<AVPacket*, arg1_type>();
+  memset(arg1, 0, sizeof(*arg1));
+  arg1->stream_index = stream_index;
+  arg1->data = const_cast<uint8*>(data);
+  arg1->size = size;
+
+  // Increment number of packets allocated.
+  MockFFmpeg::get()->inc_outstanding_packets();
+
+  return 0;
+}
+
+// Used for simulating av_new_packet().
+ACTION(NewPacket) {
+  ::testing::StaticAssertTypeEq<AVPacket*, arg0_type>();
+  int size = arg1;
+  memset(arg0, 0, sizeof(*arg0));
+  arg0->data = new uint8[size];
+  arg0->size = size;
+  arg0->destruct = &MockFFmpeg::DestructPacket;
+
+  // Increment number of packets allocated.
+  MockFFmpeg::get()->inc_outstanding_packets();
+
+  return 0;
+}
+
+// Used for simulating av_free_packet().
+ACTION(FreePacket) {
+  ::testing::StaticAssertTypeEq<AVPacket*, arg0_type>();
+
+  // Call the destructor if present, such as the one assigned in NewPacket().
+  if (arg0->destruct) {
+    arg0->destruct(arg0);
+  }
+
+  // Decrement number of packets allocated.
+  MockFFmpeg::get()->dec_outstanding_packets();
+}
+
 }  // namespace media
 
 #endif  // MEDIA_BASE_MOCK_FFMPEG_H_