Description and example is here: #3286

Is was planning to add third commit ( PiotrPrzybylak@5fe1060 ) that replaces code in Only with calls to other verifiers, but I will do it in other PR since it breaks some tests for now:

public class Only implements VerificationMode {

    private final Times once = new Times(1);

    private final NoMoreInteractions noMoreInteractions = new NoMoreInteractions();

    @Override
    public void verify(VerificationData data) {
        once.verify(data);
        noMoreInteractions.verify(data);
    }

    @Override
    public String toString() {
        return "Wanted invocations count: 1 and no other method invoked";
    }
}

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