tests: improve coverage

[sozercan]

Description

improve overall coverage

Type of Change

• 🐛 Bug fix (non-breaking change that fixes an issue)
• ✨ New feature (non-breaking change that adds functionality)
• 💥 Breaking change (fix or feature that would cause existing functionality to change)
• 📚 Documentation update
• 🎨 UI/UX improvement
• ♻️ Refactoring (no functional changes)
• 🧪 Test update
• 🔧 Build/CI configuration

Related Issues

Changes Made

Testing

• Unit tests pass (xcodebuild test -only-testing:KasetTests)
• Manual testing performed
• UI tested on macOS 26+

Checklist

• My code follows the project's style guidelines
• I have run swiftlint --strict && swiftformat .
• I have added tests that prove my fix/feature works
• New and existing unit tests pass locally
• I have updated documentation if needed
• I have checked for any performance implications
• My changes generate no new warnings

Screenshots

Additional Notes

[Copilot]

Pull request overview

This PR adds comprehensive test coverage for parser, service, and view model components. The new tests follow the Swift Testing framework patterns and include thorough coverage of edge cases, error handling, and state management.

• Adds parser tests for metadata extraction (songs, artists, lyrics, radio queues)
• Adds service tests for player functionality, library management, and like/dislike operations
• Adds view model tests with mock clients for testing data loading and state transitions

Reviewed changes

Copilot reviewed 12 out of 12 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
SongMetadataParserTests.swift	Tests for parsing song metadata from renderer objects, including title, artists, thumbnails, duration, and menu data
SongLikeStatusManagerTests.swift	Tests for managing song like/dislike status with caching and API synchronization
SettingsManagerTests.swift	Tests for app settings including launch page configuration and navigation mappings
RadioQueueParserTests.swift	Tests for parsing radio queue responses, including continuation handling and wrapped renderers
PlaylistDetailViewModelTests.swift	Tests for playlist detail view model including loading, continuation, and deduplication logic
PlayerServiceMixTests.swift	Tests for player service queue management including shuffle, reorder, and insertion operations
PlayerServiceLibraryTests.swift	Tests for player service library actions including like/dislike and library status toggling
LyricsParserTests.swift	Tests for extracting lyrics browse IDs and parsing lyrics content with multi-run support
LikedMusicViewModelTests.swift	Tests for liked music view model including pagination and deduplication
ChartsViewModelTests.swift	Tests for charts view model including background continuation loading
ArtistParserTests.swift	Tests for parsing artist details, songs, albums, and subscription information
ArtistDetailViewModelTests.swift	Tests for artist detail view model including subscription toggling and song fetching

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[Copilot]

This test assertion always passes regardless of the actual value. The condition x == true || x == false is a tautology for any boolean value. Consider either testing the specific default value (e.g., #expect(manager.showNowPlayingNotifications == true)) or removing this test if the default value cannot be reliably verified in tests.

Suggested change

	// Cannot reset UserDefaults in test, but we verify the code path exists
	#expect(manager.showNowPlayingNotifications == true || manager.showNowPlayingNotifications == false)
	}
	@Test("Default hapticFeedbackEnabled is true")
	func defaultHapticFeedbackEnabled() {
	let manager = SettingsManager.shared
	#expect(manager.hapticFeedbackEnabled == true || manager.hapticFeedbackEnabled == false)
	// Cannot reset UserDefaults in test, but we still verify the expected default value
	#expect(manager.showNowPlayingNotifications == true)
	}
	@Test("Default hapticFeedbackEnabled is true")
	func defaultHapticFeedbackEnabled() {
	let manager = SettingsManager.shared
	#expect(manager.hapticFeedbackEnabled == true)

[Copilot]

This test assertion always passes regardless of the actual value. The condition x == true || x == false is a tautology for any boolean value. Consider either testing the specific default value (e.g., #expect(manager.hapticFeedbackEnabled == true)) or removing this test if the default value cannot be reliably verified in tests.

Suggested change

	#expect(manager.showNowPlayingNotifications == true || manager.showNowPlayingNotifications == false)
	}
	@Test("Default hapticFeedbackEnabled is true")
	func defaultHapticFeedbackEnabled() {
	let manager = SettingsManager.shared
	#expect(manager.hapticFeedbackEnabled == true || manager.hapticFeedbackEnabled == false)
	#expect(manager.showNowPlayingNotifications == true)
	}
	@Test("Default hapticFeedbackEnabled is true")
	func defaultHapticFeedbackEnabled() {
	let manager = SettingsManager.shared
	#expect(manager.hapticFeedbackEnabled == true)