---
title: "testUnknownCommand(with:completionHandler:)"
framework: matter
role: symbol
role_heading: Instance Method
path: "matter/mtrbaseclustertestcluster/testunknowncommand(with:completionhandler:)"
---

# testUnknownCommand(with:completionHandler:)

## Declaration

```swift
func testUnknownCommand(with params: MTRTestClusterClusterTestUnknownCommandParams?, completionHandler: @escaping @Sendable ((any Error)?) -> Void)
```

```swift
func testUnknownCommand(with params: MTRTestClusterClusterTestUnknownCommandParams?) async throws
```