fixed an issue where the frame rate could not be configured when attaching a video using attachVideo.

[shogo4405]

Description & motivation

• fixed memory-leak MediaMixer.
• fixed an issue where the frame rate could not be configured when attaching a video using attachVideo.

try await mixer.attachVideo(AVCaptureDevice.default(for: .video), track: 0) { unit in
  try unit.setFrameRate(60)
}

Type of change

• Bug fix (non-breaking change which fixes an issue)

Screenshots:

[Copilot]

Pull Request Overview

This PR fixes two issues: a memory leak in MediaMixer and the inability to configure frame rate when attaching video devices. The key changes refactor device initialization to occur at attachment time rather than lazily, allowing configuration blocks to execute before devices are added to the capture session.

Key Changes:

• Moved device initialization from lazy creation to attachment time, enabling proper configuration
• Changed isMultiTrackAudioMixingEnabled from computed to stored property to fix memory leak
• Added test coverage for memory leak fixes and video configuration functionality

Reviewed Changes

Copilot reviewed 9 out of 10 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
HaishinKit/Sources/Mixer/MediaMixer.swift	Removed initialization task and changed isMultiTrackAudioMixingEnabled to stored property; simplified attachVideo to delegate configuration to VideoCaptureUnit
HaishinKit/Sources/Mixer/VideoCaptureUnit.swift	Refactored attachVideo to create VideoDeviceUnit instances at attachment time and apply configuration before session attachment
HaishinKit/Sources/Mixer/VideoDeviceUnit.swift	Changed initialization to require device parameter; moved device setup from attachDevice to initializer; renamed data output class
HaishinKit/Sources/Mixer/AudioCaptureUnit.swift	Refactored attachAudio to create AudioDeviceUnit at attachment time; added isMultiTrackAudioMixingEnabled parameter to initializer
HaishinKit/Sources/Mixer/AudioDeviceUnit.swift	Changed initializer to require device parameter and perform full initialization; removed attachDevice method
HaishinKit/Sources/Mixer/DeviceUnit.swift	Updated protocol to require device parameter in initializer
HaishinKit/Tests/Mixer/MediaMixerTests.swift	Added test for video configuration and uncommented memory leak test
HaishinKit/Tests/Mixer/VideoDeviceUnitTests.swift	Added new test file for VideoDeviceUnit memory leak verification
HaishinKit/Tests/Mixer/AudioDeviceUnitTests.swift	Added new test file for AudioDeviceUnit memory leak verification

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[Copilot]

Potential crash when detaching a nil device. If devices[track] is nil (e.g., on first attachment), calling detachCapture with nil may cause issues depending on the implementation. Consider checking if the device exists before detaching: if let device = self.devices[track] { session.detachCapture(device) }

Suggested change

	session.detachCapture(self.devices[track])
	if let device = self.devices[track] {
	session.detachCapture(device)
	}

[Copilot]

Potential crash when detaching a nil device. If devices[track] is nil (e.g., on first attachment), calling detachCapture with nil may cause issues depending on the implementation. Consider checking if the device exists before detaching: if let device = self.devices[track] { session.detachCapture(device) }

Suggested change

	session.detachCapture(self.devices[track])
	if let device = self.devices[track] {
	session.detachCapture(device)
	}