---
title: "testUnknownCommand(completion:)"
framework: matter
role: symbol
role_heading: Instance Method
path: "matter/mtrbaseclusterunittesting/testunknowncommand(completion:)"
---

# testUnknownCommand(completion:)

## Declaration

```swift
func testUnknownCommand(completion: @escaping @Sendable ((any Error)?) -> Void)
```

```swift
func testUnknownCommand() async throws
```