Add occ flag check to context (#340)

## Describe your changes and provide context
- Allows sei-chain to ask isOCCEnabled() so that it can choose to use
the OCC logic
- Sei-chain can set this to true according to desired logic

## Testing performed to validate your change
- unit test that sets flag and verifies value

types/context.go

@@ -34,6 +34,7 @@ type Context struct {
 	voteInfo      []abci.VoteInfo
 	gasMeter      GasMeter
 	blockGasMeter GasMeter
+	occEnabled    bool
 	checkTx       bool
 	recheckTx     bool // if recheckTx == true, then checkTx must also be true
 	minGasPrice   DecCoins
@@ -104,6 +105,10 @@ func (c Context) IsReCheckTx() bool {
 	return c.recheckTx
 }
 
+func (c Context) IsOCCEnabled() bool {
+	return c.occEnabled
+}
+
 func (c Context) MinGasPrices() DecCoins {
 	return c.minGasPrice
 }
@@ -281,6 +286,12 @@ func (c Context) WithIsCheckTx(isCheckTx bool) Context {
 	return c
 }
 
+// WithIsOCCEnabled enables or disables whether OCC is used as the concurrency algorithm
+func (c Context) WithIsOCCEnabled(isOCCEnabled bool) Context {
+	c.occEnabled = isOCCEnabled
+	return c
+}
+
 // WithIsRecheckTx called with true will also set true on checkTx in order to
 // enforce the invariant that if recheckTx = true then checkTx = true as well.
 func (c Context) WithIsReCheckTx(isRecheckTx bool) Context {

types/context_test.go

@@ -87,6 +87,7 @@ func (s *contextTestSuite) TestContextWithCustom() {
 	height := int64(1)
 	chainid := "chainid"
 	ischeck := true
+	isOCC := true
 	txbytes := []byte("txbytes")
 	logger := mocks.NewMockLogger(ctrl)
 	voteinfos := []abci.VoteInfo{{}}
@@ -106,10 +107,13 @@ func (s *contextTestSuite) TestContextWithCustom() {
 		WithGasMeter(meter).
 		WithMinGasPrices(minGasPrices).
 		WithBlockGasMeter(blockGasMeter).
-		WithHeaderHash(headerHash)
+		WithHeaderHash(headerHash).
+		WithIsOCCEnabled(isOCC)
+
 	s.Require().Equal(height, ctx.BlockHeight())
 	s.Require().Equal(chainid, ctx.ChainID())
 	s.Require().Equal(ischeck, ctx.IsCheckTx())
+	s.Require().Equal(isOCC, ctx.IsOCCEnabled())
 	s.Require().Equal(txbytes, ctx.TxBytes())
 	s.Require().Equal(logger, ctx.Logger())
 	s.Require().Equal(voteinfos, ctx.VoteInfos())