class Host {
  constructor() /* primary */ {
    super/*Any*/()
    /* <init>() */

  }

  operator fun plusAssign(x: Int) {
  }

  fun test1() {
    <this>.plusAssign(x = 1)
  }

}

fun foo(): Host {
  return Host()
}

fun Host.test2() {
  <this>.plusAssign(x = 1)
}

fun test3() {
  foo().plusAssign(x = 1)
}

fun test4(a: Function0<Host>) {
  a.invoke().plusAssign(x = 1)
}