Proof using.
intros.
unfold handleRequestVoteReply, advanceCurrentTerm in *.
repeat break_match; subst; simpl in *; auto; congruence.
Qed.

Lemma handleRequestVoteReply_votesReceived :
forall h st src t v st' crony,
handleRequestVoteReply h st src t v = st' ->
In crony (votesReceived st') ->
((crony = src /\ v = true /\ currentTerm st' = t) \/ In crony (votesReceived st)).