kotlin-fork/compiler/testData/diagnostics/tests/when/ExhaustiveBooleanNullable.kt

// FIR_IDENTICAL
// See also: KT-3743
fun foo(arg: Boolean?): String {
    // Must be exhaustive
    return when(arg) {
        true -> "truth"
        false -> "falsehood"
        null -> "unknown"
    }
}