Proof using.
unfold handleRequestVoteReply.
intros.
repeat break_match; simpl; auto using advanceCurrentTerm_matchIndex_preserved;
simpl in *; try congruence.
unfold assoc_default. simpl.
repeat break_match; simpl in *; try congruence; find_inversion; auto.
Qed.

Lemma doLeader_matchIndex_preserved :
forall st h os st' ms,
doLeader st h = (os, st', ms) ->
matchIndex_preserved st st'.