Function
waitUntilExactlyOneExists
Common
```kotlin
@ExperimentalTestApi
fun ComposeUiTest.waitUntilExactlyOneExists(
matcher: SemanticsMatcher,
timeoutMillis: Long = 1_000L,
) = waitUntilNodeCount(matcher, 1, timeoutMillis)
```
Blocks until exactly one node matches the given `matcher`.
#### Parameters
| | |
| --- | --- |
| matcher | The matcher that will be used to filter nodes. |
| timeoutMillis | The time after which this method throws an exception if exactly one node does not match the given `matcher`. This observes wall clock time, not frame time. |