<@U0E7VBZS7>: in that case `Action1` is from RxJav...

# test

[artem_zin]

@savekirk: in that case Action1 is from RxJava, but you can create your own similar functional interface:

fun test() {
  val subj = mock(Action1<String>()::class.java)

  foo({ subj.call(it) })
  
  verify(subj).call(expectedArg)
}