Increase CI-safe test coverage

[omaralbeik]

Summary

• Add CI-safe coverage across thumbnail coordination/cancellation, PiP playback state handling, pixel-buffer rendering, player event handling, libVLC event mapping, dialog/VLC instance registration, media/discovery edge cases, playlist validation, and equalizer error handling.
• Include a small production guard fix for MediaListPlayer so index/item playback fails with invalidState when no media list is attached instead of forwarding the invalid state to libVLC.
• Push local CI-mode source coverage to 89.19% in the exported lcov report.

Verification

• /opt/homebrew/bin/swiftformat Sources Tests Showcase --lint --strict
• /opt/homebrew/bin/swiftlint lint --strict --quiet Sources Tests Showcase
• CI=1 xcrun swift test --no-parallel --enable-code-coverage (1394 tests in 109 suites)
• scripts/export-lcov.sh

Remaining coverage constraints

The largest remaining uncovered areas are private macOS PiP integration, libVLC callback-only dialog/thumbnail/renderer paths, renderer items that require real libVLC-owned pointers, and live playback / structured-media paths that are intentionally skipped in CI to avoid audio/video-output instability.

[Copilot]

Pull request overview

This PR expands CI-safe test coverage across SwiftVLC’s higher-level wrappers (Player, PiP, thumbnails, discovery, dialog registration, playlists, and equalizer), focusing on edge cases and cancellation/branch behavior that’s hard to hit in headless CI. All changes are in the test target only.

Changes:

• Add new/extended integration & logic tests for playback state transitions, event mapping, PiP controllers/backends, and pixel-buffer rendering paths.
• Add thumbnail coordination + cancellation coverage (including queued acquisition and already-cancelled tasks).
• Add validation/edge-case tests for discovery init, dialog registration slotting, playlist play input validation, and equalizer error handling.

Reviewed changes

Copilot reviewed 20 out of 20 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
Tests/SwiftVLCTests/Playlist/MediaListPlayerRebuildTests.swift	Adds coverage for MediaListPlayer.play(at:) input validation and basic play/stop paths.
Tests/SwiftVLCTests/Player/PlayerWithMediaBranchTests.swift	Adds branch coverage for media replacement via play(_:) when cached state is active.
Tests/SwiftVLCTests/Player/PlayerThrowsTests.swift	Adds an error-path test for deinterlace mode handling.
Tests/SwiftVLCTests/Player/PlayerEventHandlerTests.swift	Adds coverage for additional event→observable-state mutations and native state sync helpers.
Tests/SwiftVLCTests/Player/PlayerBranchCoverageTests.swift	Extends no-crash branch coverage for selectProgram(id:) with extreme IDs.
Tests/SwiftVLCTests/Player/MapEventTests.swift	Adds mapping tests for audio device, recording, and snapshot libVLC event payloads.
Tests/SwiftVLCTests/PiP/PixelBufferRendererTests.swift	Adds coverage for render-generation stability, pool reuse, and unallocatable scaling behavior.
Tests/SwiftVLCTests/PiP/PixelBufferRendererCallbackTests.swift	Adds callback coverage for timebase-driven presentation timestamps.
Tests/SwiftVLCTests/PiP/PiPVideoViewTests.swift	Adds macOS PiP backend/media-controller edge-case coverage.
Tests/SwiftVLCTests/PiP/PiPControllerInteractionTests.swift	Adds coverage for deferred pause retry, external intent supersession, and deinit cleanup branching.
Tests/SwiftVLCTests/Media/TrackExtendedTests.swift	Adds coverage for C subtitle track encoding mapping and field clearing.
Tests/SwiftVLCTests/Media/ThumbnailCoordinatorTests.swift	New tests for queued acquisition, cancellation while waiting, and skipped cancelled waiters.
Tests/SwiftVLCTests/Media/ThumbnailCancellationTests.swift	Adds CI-safe completion/failure coverage for audio-only/video thumbnail requests and already-cancelled tasks.
Tests/SwiftVLCTests/Media/MediaErrorPathsTests.swift	Adds coverage for cancelled parse behavior (typed failure shape).
Tests/SwiftVLCTests/Discovery/RendererDiscovererTests.swift	Adds init-with-empty-name error-path coverage.
Tests/SwiftVLCTests/Discovery/MediaDiscovererTests.swift	Adds init-with-empty-name error-path coverage.
Tests/SwiftVLCTests/Core/VLCInstanceTests.swift	Adds dialog registration slot claiming/releasing + deinit cleanup coverage.
Tests/SwiftVLCTests/Core/InputValidationTests.swift	Adds coverage for checkedNonnegativeInt32 success cases.
Tests/SwiftVLCTests/Core/DialogHandlerExtendedTests.swift	Adds coverage for rejecting unrepresentable QuestionRequest actions.
Tests/SwiftVLCTests/Audio/EqualizerBandsTests.swift	Adds coverage for rejecting NaN amplification values.

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[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.

📢 Thoughts on this report? Let us know!

[Copilot]

Pull request overview

Copilot reviewed 23 out of 23 changed files in this pull request and generated 3 comments.

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