Files
kotlin-fork/compiler/testData/diagnostics/tests/dataFlowInfoTraversal/When.fir.kt
T
Tianyu Geng c7272f6986 FIR checker: SENSELESS_(COMPARISON|NULL_IN_WHEN)
Currently DFA does not set "definitely equal to null" for access to variables that got assigned `null`. For example, FIR should mark the following line as SENSELESS_COMPARISON due to `s = null` above.
 https://github.com/JetBrains/kotlin/blob/d1531f9cdd5852352c0133198706125dc63b6007/compiler/testData/diagnostics/tests/smartCasts/alwaysNull.fir.kt#L6

The problem is at https://github.com/JetBrains/kotlin/blob/7e9f27436a77de1c76e3705da7aa1fbe8938336b/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/dfa/FirDataFlowAnalyzer.kt#L1104

For null assignment, ideally the type should be `Nothing?`. This is
addressed in a followup commit instead.
2021-08-06 22:57:16 +03:00

19 lines
312 B
Kotlin
Vendored

fun bar(x: Int): Int = x + 1
fun foo() {
val x: Int? = null
if (x != null) {
when (x) {
0 -> bar(x)
else -> {}
}
}
when (x) {
0 -> { if (<!SENSELESS_COMPARISON!>x == null<!>) return }
else -> { if (x == null) return }
}
bar(x)
}