Add unit tests for avfoundation format mapper functions and fix wrong implementation.

webrtc/sdk/objc/Framework/Classes/avfoundationformatmapper.mm

 /*
  *  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 "avfoundationformatmapper.h"
 
 #import "WebRTC/RTCLogging.h"
 
 // TODO(denicija): add support for higher frame rates.
 // See http://crbug/webrtc/6355 for more info.
 static const int kFramesPerSecond = 30;
 
 static inline BOOL IsMediaSubTypeSupported(FourCharCode mediaSubType) {
   return (mediaSubType == kCVPixelFormatType_420YpCbCr8PlanarFullRange ||
           mediaSubType == kCVPixelFormatType_420YpCbCr8BiPlanarVideoRange);
 }
 
 static inline BOOL IsFrameRateWithinRange(int fps, AVFrameRateRange* range) {
   return range.minFrameRate <= fps && range.maxFrameRate >= fps;
 }
 
 // Returns filtered array of device formats based on predefined constraints our
 // stack imposes.
-static NSArray<AVCaptureDeviceFormat*>* GetEligibleDeviceFormats(
+NSArray<AVCaptureDeviceFormat*>* GetEligibleDeviceFormats(

[magjed_webrtc, 2016/11/28 12:21:23]

You are not allowed to expose implementation details from .cc or .mm files.
Every exposed function needs to be present in the header file. I understand you
want to test these functions directly, but I discourage you from doing that
since they are implementation details. Test only the public functions
GetSupportedVideoFormatsForDevice and SetFormatForCaptureDevice.

     const AVCaptureDevice* device,
     int supportedFps) {
   NSMutableArray<AVCaptureDeviceFormat*>* eligibleDeviceFormats =
       [NSMutableArray array];
 
   for (AVCaptureDeviceFormat* format in device.formats) {
     // Filter out subTypes that we currently don't support in the stack
     FourCharCode mediaSubType =
         CMFormatDescriptionGetMediaSubType(format.formatDescription);
     if (!IsMediaSubTypeSupported(mediaSubType)) {
       continue;
     }
 
     // Filter out frame rate ranges that we currently don't support in the stack
     for (AVFrameRateRange* frameRateRange in format.videoSupportedFrameRateRanges) {
       if (IsFrameRateWithinRange(supportedFps, frameRateRange)) {
         [eligibleDeviceFormats addObject:format];
         break;
       }
     }
   }
 
   return [eligibleDeviceFormats copy];
 }
 
 // Mapping from cricket::VideoFormat to AVCaptureDeviceFormat.
-static AVCaptureDeviceFormat* GetDeviceFormatForVideoFormat(
+AVCaptureDeviceFormat* GetDeviceFormatForVideoFormat(
     const AVCaptureDevice* device,
     const cricket::VideoFormat& videoFormat) {
   AVCaptureDeviceFormat* desiredDeviceFormat = nil;
   NSArray<AVCaptureDeviceFormat*>* eligibleFormats =
       GetEligibleDeviceFormats(device, videoFormat.framerate());
 
   for (AVCaptureDeviceFormat* deviceFormat in eligibleFormats) {
     CMVideoDimensions dimension =
         CMVideoFormatDescriptionGetDimensions(deviceFormat.formatDescription);
     FourCharCode mediaSubType =
@@ skipping 58 matching lines @@
   } else {
     RTCLogError(@"Failed to lock device %@. Error: %@", device, error.userInfo);
     success = false;
   }
   [session commitConfiguration];
 
   return success;
 }
 
 }  // namespace webrtc