e2e: clean up generation of evidence (#6904)

types/evidence.go

@@ -46,15 +46,20 @@ type DuplicateVoteEvidence struct {
 var _ Evidence = &DuplicateVoteEvidence{}
 
 // NewDuplicateVoteEvidence creates DuplicateVoteEvidence with right ordering given
-// two conflicting votes. If one of the votes is nil, evidence returned is nil as well
-func NewDuplicateVoteEvidence(vote1, vote2 *Vote, blockTime time.Time, valSet *ValidatorSet) *DuplicateVoteEvidence {
+// two conflicting votes. If either of the votes is nil, the val set is nil or the voter is
+// not in the val set, an error is returned
+func NewDuplicateVoteEvidence(vote1, vote2 *Vote, blockTime time.Time, valSet *ValidatorSet,
+) (*DuplicateVoteEvidence, error) {
 	var voteA, voteB *Vote
-	if vote1 == nil || vote2 == nil || valSet == nil {
-		return nil
+	if vote1 == nil || vote2 == nil {
+		return nil, errors.New("missing vote")
+	}
+	if valSet == nil {
+		return nil, errors.New("missing validator set")
 	}
 	idx, val := valSet.GetByAddress(vote1.ValidatorAddress)
 	if idx == -1 {
-		return nil
+		return nil, errors.New("validator not in validator set")
 	}
 
 	if strings.Compare(vote1.BlockID.Key(), vote2.BlockID.Key()) == -1 {
@@ -70,7 +75,7 @@ func NewDuplicateVoteEvidence(vote1, vote2 *Vote, blockTime time.Time, valSet *V
 		TotalVotingPower: valSet.TotalVotingPower(),
 		ValidatorPower:   val.VotingPower,
 		Timestamp:        blockTime,
-	}
+	}, nil
 }
 
 // ABCI returns the application relevant representation of the evidence
@@ -92,7 +97,7 @@ func (dve *DuplicateVoteEvidence) Bytes() []byte {
 	pbe := dve.ToProto()
 	bz, err := pbe.Marshal()
 	if err != nil {
-		panic(err)
+		panic("marshaling duplicate vote evidence to bytes: " + err.Error())
 	}
 
 	return bz
@@ -260,11 +265,11 @@ func (l *LightClientAttackEvidence) ABCI() []abci.Evidence {
 func (l *LightClientAttackEvidence) Bytes() []byte {
 	pbe, err := l.ToProto()
 	if err != nil {
-		panic(err)
+		panic("converting light client attack evidence to proto: " + err.Error())
 	}
 	bz, err := pbe.Marshal()
 	if err != nil {
-		panic(err)
+		panic("marshaling light client attack evidence to bytes: " + err.Error())
 	}
 	return bz
 }
@@ -684,7 +689,11 @@ func NewMockDuplicateVoteEvidenceWithValidator(height int64, time time.Time,
 	vB := voteB.ToProto()
 	_ = pv.SignVote(context.Background(), chainID, vB)
 	voteB.Signature = vB.Signature
-	return NewDuplicateVoteEvidence(voteA, voteB, time, NewValidatorSet([]*Validator{val}))
+	ev, err := NewDuplicateVoteEvidence(voteA, voteB, time, NewValidatorSet([]*Validator{val}))
+	if err != nil {
+		panic("constructing mock duplicate vote evidence: " + err.Error())
+	}
+	return ev
 }
 
 func makeMockVote(height int64, round, index int32, addr Address,

types/evidence_test.go

@@ -85,7 +85,8 @@ func TestDuplicateVoteEvidenceValidation(t *testing.T) {
 			vote1 := makeVote(t, val, chainID, math.MaxInt32, math.MaxInt64, math.MaxInt32, 0x02, blockID, defaultVoteTime)
 			vote2 := makeVote(t, val, chainID, math.MaxInt32, math.MaxInt64, math.MaxInt32, 0x02, blockID2, defaultVoteTime)
 			valSet := NewValidatorSet([]*Validator{val.ExtractIntoValidator(10)})
-			ev := NewDuplicateVoteEvidence(vote1, vote2, defaultVoteTime, valSet)
+			ev, err := NewDuplicateVoteEvidence(vote1, vote2, defaultVoteTime, valSet)
+			require.NoError(t, err)
 			tc.malleateEvidence(ev)
 			assert.Equal(t, tc.expectErr, ev.ValidateBasic() != nil, "Validate Basic had an unexpected result")
 		})