From 08aa4765b07641a7d1e9f84e9b1be7b6172dbd78 Mon Sep 17 00:00:00 2001
From: Callum <cmwaters19@gmail.com>
Date: Tue, 28 Apr 2020 12:54:13 +0200
Subject: [PATCH] create tests for validating evidence

---
 state/validation.go      |  2 +-
 state/validation_test.go | 66 +++++++++++++++++++++++++++++++++++++---
 types/evidence.go        |  8 ++++-
 3 files changed, 69 insertions(+), 7 deletions(-)

diff --git a/state/validation.go b/state/validation.go
index aecfd42c8..c3231c270 100644
--- a/state/validation.go
+++ b/state/validation.go
@@ -137,7 +137,7 @@ func validateBlock(evidencePool EvidencePool, stateDB dbm.DB, state State, block
 				return types.NewErrEvidenceInvalid(ev, errors.New("evidence was already committed"))
 			}
 			if evidencePool.IsPending(ev) {
-				return nil
+				continue
 			}
 		}
 		if err := VerifyEvidence(stateDB, state, ev, &block.Header); err != nil {
diff --git a/state/validation_test.go b/state/validation_test.go
index 10ff4c8ea..1be09c8dc 100644
--- a/state/validation_test.go
+++ b/state/validation_test.go
@@ -8,6 +8,7 @@ import (
 
 	"github.com/tendermint/tendermint/crypto/ed25519"
 	"github.com/tendermint/tendermint/crypto/tmhash"
+	evmock "github.com/tendermint/tendermint/evidence/mock"
 	"github.com/tendermint/tendermint/libs/log"
 	"github.com/tendermint/tendermint/mock"
 	sm "github.com/tendermint/tendermint/state"
@@ -98,7 +99,7 @@ func TestValidateBlockCommit(t *testing.T) {
 		log.TestingLogger(),
 		proxyApp.Consensus(),
 		mock.Mempool{},
-		sm.MockEvidencePool{},
+		evmock.NewDefaultEvidencePool(),
 	)
 	lastCommit := types.NewCommit(0, 0, types.BlockID{}, nil)
 	wrongSigsCommit := types.NewCommit(1, 0, types.BlockID{}, nil)
@@ -205,7 +206,7 @@ func TestValidateBlockEvidence(t *testing.T) {
 		log.TestingLogger(),
 		proxyApp.Consensus(),
 		mock.Mempool{},
-		sm.MockEvidencePool{},
+		evmock.NewDefaultEvidencePool(),
 	)
 	lastCommit := types.NewCommit(0, 0, types.BlockID{}, nil)
 
@@ -260,15 +261,70 @@ func TestValidateFailBlockOnCommittedEvidence(t *testing.T) {
 	var height int64 = 1
 	state, stateDB, _ := makeState(1, int(height))
 
-	blockExec := sm.NewBlockExecutor(stateDB, log.TestingLogger(), nil, nil, mockEvPoolAlwaysCommitted{})
+	evpool := evmock.NewDefaultEvidencePool()
+	blockExec := sm.NewBlockExecutor(
+		stateDB, log.TestingLogger(),
+		nil,
+		nil,
+		evpool)
 	// A block with a couple pieces of evidence passes.
 	block := makeBlock(state, height)
 	addr, _ := state.Validators.GetByIndex(0)
-	alreadyCommittedEvidence := types.NewMockEvidence(height, time.Now(), addr)
-	block.Evidence.Evidence = []types.Evidence{alreadyCommittedEvidence}
+	evpool.CommitEvidence(evpool.AddMockEvidence(height, addr))
+	block.Evidence.Evidence = evpool.CommittedEvidenceList
 	block.EvidenceHash = block.Evidence.Hash()
 	err := blockExec.ValidateBlock(state, block)
 
 	require.Error(t, err)
 	require.IsType(t, err, &types.ErrEvidenceInvalid{})
 }
+
+func TestValidateAlreadyPendingEvidence(t *testing.T) {
+	var height int64 = 1
+	state, stateDB, _ := makeState(2, int(height))
+
+	evpool := evmock.NewDefaultEvidencePool()
+	blockExec := sm.NewBlockExecutor(
+		stateDB, log.TestingLogger(),
+		nil,
+		nil,
+		evpool)
+	// A block with a couple pieces of evidence passes.
+	block := makeBlock(state, height)
+	addr, _ := state.Validators.GetByIndex(0)
+	addr2, _ := state.Validators.GetByIndex(0)
+	// add pending evidence
+	pendingEv := evpool.AddMockEvidence(height, addr)
+	// add evidence that hasn't seen before
+	ev := types.NewMockEvidence(height, time.Now(), addr2)
+	block.Evidence.Evidence = []types.Evidence{pendingEv, ev}
+	block.EvidenceHash = block.Evidence.Hash()
+	err := blockExec.ValidateBlock(state, block)
+
+	require.NoError(t, err)
+}
+
+// TODO: prevent committing duplicate votes
+//func TestValidateDuplicateEvidenceShouldFail(t *testing.T) {
+//	var height int64 = 1
+//	var evidence []types.Evidence
+//	state, stateDB, _ := makeState(1, int(height))
+//
+//	evpool := evmock.NewDefaultEvidencePool()
+//	blockExec := sm.NewBlockExecutor(
+//		stateDB, log.TestingLogger(),
+//		nil,
+//		nil,
+//		evpool)
+//	// A block with a couple pieces of evidence passes.
+//	block := makeBlock(state, height)
+//	addr, _ := state.Validators.GetByIndex(0)
+//	for i := 0; i < 2; i++ {
+//		evidence = append(evidence, types.NewMockEvidence(height, time.Now(), addr))
+//	}
+//	block.Evidence.Evidence = evidence
+//	block.EvidenceHash = block.Evidence.Hash()
+//	err := blockExec.ValidateBlock(state, block)
+//
+//	require.Error(t, err)
+//}
diff --git a/types/evidence.go b/types/evidence.go
index 9dd7c9823..fef9977c0 100644
--- a/types/evidence.go
+++ b/types/evidence.go
@@ -975,7 +975,13 @@ func (e MockEvidence) Bytes() []byte {
 	return []byte(fmt.Sprintf("%d-%x-%s",
 		e.EvidenceHeight, e.EvidenceAddress, e.EvidenceTime))
 }
-func (e MockEvidence) Verify(chainID string, pubKey crypto.PubKey) error { return nil }
+func (e MockEvidence) Verify(chainID string, pubKey crypto.PubKey) error {
+	if !bytes.Equal(pubKey.Address(), e.Address()) {
+		return fmt.Errorf("address (%X) doesn't match pubkey (%v - %X)",
+			e.Address(), pubKey, pubKey.Address())
+	}
+	return nil
+}
 func (e MockEvidence) Equal(ev Evidence) bool {
 	e2 := ev.(MockEvidence)
 	return e.EvidenceHeight == e2.EvidenceHeight &&