Add compile-time checks that actors interfaces are correctly implemented

chain/actors/builtin/account/v0.go

@@ -6,6 +6,8 @@ import (
 	"github.com/filecoin-project/specs-actors/actors/builtin/account"
 )
 
+var _ State = (*state0)(nil)
+
 type state0 struct {
 	account.State
 	store adt.Store

chain/actors/builtin/init/v0.go

@@ -13,6 +13,8 @@ import (
 	adt0 "github.com/filecoin-project/specs-actors/actors/util/adt"
 )
 
+var _ State = (*state0)(nil)
+
 type state0 struct {
 	init_.State
 	store adt.Store

chain/actors/builtin/market/v0.go

@@ -12,6 +12,8 @@ import (
 	cbg "github.com/whyrusleeping/cbor-gen"
 )
 
+var _ State = (*state0)(nil)
+
 type state0 struct {
 	market.State
 	store adt.Store

chain/actors/builtin/miner/v0.go

@@ -17,6 +17,8 @@ import (
 	miner0 "github.com/filecoin-project/specs-actors/actors/builtin/miner"
 )
 
+var _ State = (*state0)(nil)
+
 type state0 struct {
 	miner0.State
 	store adt.Store

chain/actors/builtin/multisig/v0.go

@@ -6,6 +6,8 @@ import (
 	"github.com/filecoin-project/specs-actors/actors/builtin/multisig"
 )
 
+var _ State = (*state0)(nil)
+
 type state0 struct {
 	multisig.State
 	store adt.Store

chain/actors/builtin/paych/v0.go

@@ -9,6 +9,8 @@ import (
 	adt0 "github.com/filecoin-project/specs-actors/actors/util/adt"
 )
 
+var _ State = (*state0)(nil)
+
 type state0 struct {
 	paych.State
 	store adt.Store

chain/actors/builtin/power/v0.go

@@ -8,6 +8,8 @@ import (
 	"github.com/filecoin-project/specs-actors/actors/util/adt"
 )
 
+var _ State = (*state0)(nil)
+
 type state0 struct {
 	power0.State
 	store adt.Store

chain/actors/builtin/reward/v0.go

@@ -9,6 +9,8 @@ import (
 	"github.com/filecoin-project/specs-actors/actors/util/smoothing"
 )
 
+var _ State = (*state0)(nil)
+
 type state0 struct {
 	reward.State
 	store adt.Store

chain/actors/builtin/verifreg/v0.go

@@ -11,6 +11,8 @@ import (
 	"github.com/filecoin-project/lotus/chain/actors/adt"
 )
 
+var _ State = (*state0)(nil)
+
 type state0 struct {
 	verifreg0.State
 	store adt.Store