From 6112578d07c97033380ac4c5902c5bcb108d8340 Mon Sep 17 00:00:00 2001
From: Ethan Buchman <ethan@coinculture.info>
Date: Thu, 28 Dec 2017 19:35:56 -0500
Subject: [PATCH] ValidateBlock is a method on blockExec

---
 consensus/state.go  |  7 ++++---
 node/node.go        |  2 +-
 state/execution.go  | 10 +++++++++-
 state/validation.go |  7 ++++---
 4 files changed, 18 insertions(+), 8 deletions(-)

diff --git a/consensus/state.go b/consensus/state.go
index 69858da08..518d81c58 100644
--- a/consensus/state.go
+++ b/consensus/state.go
@@ -153,6 +153,7 @@ func (cs *ConsensusState) SetLogger(l log.Logger) {
 // SetEventBus sets event bus.
 func (cs *ConsensusState) SetEventBus(b *types.EventBus) {
 	cs.eventBus = b
+	cs.blockExec.SetEventBus(b)
 }
 
 // String returns a string.
@@ -922,7 +923,7 @@ func (cs *ConsensusState) defaultDoPrevote(height int64, round int) {
 	}
 
 	// Validate proposal block
-	err := sm.ValidateBlock(cs.state, cs.ProposalBlock)
+	err := cs.blockExec.ValidateBlock(cs.state, cs.ProposalBlock)
 	if err != nil {
 		// ProposalBlock is invalid, prevote nil.
 		logger.Error("enterPrevote: ProposalBlock is invalid", "err", err)
@@ -1030,7 +1031,7 @@ func (cs *ConsensusState) enterPrecommit(height int64, round int) {
 	if cs.ProposalBlock.HashesTo(blockID.Hash) {
 		cs.Logger.Info("enterPrecommit: +2/3 prevoted proposal block. Locking", "hash", blockID.Hash)
 		// Validate the block.
-		if err := sm.ValidateBlock(cs.state, cs.ProposalBlock); err != nil {
+		if err := cs.blockExec.ValidateBlock(cs.state, cs.ProposalBlock); err != nil {
 			cmn.PanicConsensus(cmn.Fmt("enterPrecommit: +2/3 prevoted for an invalid block: %v", err))
 		}
 		cs.LockedRound = round
@@ -1165,7 +1166,7 @@ func (cs *ConsensusState) finalizeCommit(height int64) {
 	if !block.HashesTo(blockID.Hash) {
 		cmn.PanicSanity(cmn.Fmt("Cannot finalizeCommit, ProposalBlock does not hash to commit hash"))
 	}
-	if err := sm.ValidateBlock(cs.state, block); err != nil {
+	if err := cs.blockExec.ValidateBlock(cs.state, block); err != nil {
 		cmn.PanicConsensus(cmn.Fmt("+2/3 committed an invalid block: %v", err))
 	}
 
diff --git a/node/node.go b/node/node.go
index fe51b941c..04b1fb140 100644
--- a/node/node.go
+++ b/node/node.go
@@ -291,7 +291,7 @@ func NewNode(config *cfg.Config,
 	eventBus.SetLogger(logger.With("module", "events"))
 
 	// services which will be publishing and/or subscribing for messages (events)
-	blockExec.SetEventBus(eventBus)
+	// consensusReactor will set it on consensusState and blockExecutor
 	consensusReactor.SetEventBus(eventBus)
 
 	// Transaction indexing
diff --git a/state/execution.go b/state/execution.go
index 8b05733a7..b3acd711f 100644
--- a/state/execution.go
+++ b/state/execution.go
@@ -56,6 +56,14 @@ func (blockExec *BlockExecutor) SetEventBus(eventBus types.BlockEventPublisher)
 	blockExec.eventBus = eventBus
 }
 
+// ValidateBlock validates the given block against the given state.
+// If the block is invalid, it returns an error.
+// Validation does not mutate state, but does require historical information from the stateDB,
+// ie. to verify evidence from a validator at an old height.
+func (blockExec *BlockExecutor) ValidateBlock(s State, block *types.Block) error {
+	return validateBlock(blockExec.db, s, block)
+}
+
 // ApplyBlock validates the block against the state, executes it against the app,
 // fires the relevent events, commits the app, and saves the new state and responses.
 // It's the only function that needs to be called
@@ -63,7 +71,7 @@ func (blockExec *BlockExecutor) SetEventBus(eventBus types.BlockEventPublisher)
 // It takes a blockID to avoid recomputing the parts hash.
 func (blockExec *BlockExecutor) ApplyBlock(s State, blockID types.BlockID, block *types.Block) (State, error) {
 
-	if err := validateBlock(s, block); err != nil {
+	if err := blockExec.ValidateBlock(s, block); err != nil {
 		return s, ErrInvalidBlock(err)
 	}
 
diff --git a/state/validation.go b/state/validation.go
index 692008406..5c9197bcc 100644
--- a/state/validation.go
+++ b/state/validation.go
@@ -6,17 +6,18 @@ import (
 	"fmt"
 
 	"github.com/tendermint/tendermint/types"
+	dbm "github.com/tendermint/tmlibs/db"
 )
 
 //-----------------------------------------------------
 // Validate block
 
 // ValidateBlock validates the block against the state.
-func ValidateBlock(s State, block *types.Block) error {
-	return validateBlock(s, block)
+func _ValidateBlock(s State, block *types.Block) error {
+	return validateBlock(dbm.NewMemDB(), s, block)
 }
 
-func validateBlock(s State, b *types.Block) error {
+func validateBlock(stateDB dbm.DB, s State, b *types.Block) error {
 	// validate internal consistency
 	if err := b.ValidateBasic(); err != nil {
 		return err