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

/*
 * KOTLIN DIAGNOSTICS SPEC TEST (POSITIVE)
 *
 * SPEC VERSION: 0.1-152
 * PRIMARY LINKS: expressions, when-expression -> paragraph 5 -> sentence 1
 * expressions, when-expression, exhaustive-when-expressions -> paragraph 2 -> sentence 9
 * type-inference, smart-casts, smart-cast-types -> paragraph 9 -> sentence 1
 * control--and-data-flow-analysis, control-flow-graph, expressions-1, conditional-expressions -> paragraph 1 -> sentence 1
 * control--and-data-flow-analysis, control-flow-graph, expressions-1, boolean-operators -> paragraph 0 -> sentence 0
 */

// KT-7857: when exhaustiveness does not take previous nullability checks into account
enum class X { A, B }
fun foo(arg: X?): Int {
    if (arg == null) {
        return 0
    }
    else {
        return when (<!DEBUG_INFO_SMARTCAST!>arg<!>) {
            X.A -> 1
            X.B -> 2
            // else or null branch should not be required here!
        }
    } 
}