kotlin-fork/compiler/testData/diagnostics/tests/smartCasts/kt2865.fir.kt

// !WITH_NEW_INFERENCE
operator fun <K, V> MutableMap<K, V>.set(k: K, v: V) {}

fun foo(a: MutableMap<String, String>, x: String?) {
    a[x!!] = x
    a[x] = x!!
}

fun foo1(a: MutableMap<String, String>, x: String?) {
    a[x] = x!!
    a[x!!] = x
}