From 8747c6083e6ecc1c60620c8dcf67bb07a304d8d4 Mon Sep 17 00:00:00 2001
From: Steven Allen <steven@stebalien.com>
Date: Fri, 18 Sep 2020 14:20:53 -0700
Subject: [PATCH] abstract over account actor

---
 chain/actors/builtin/account/account.go | 31 +++++++++++++++++++++++++
 chain/actors/builtin/account/v0.go      | 16 +++++++++++++
 chain/vm/vm.go                          | 13 ++++-------
 3 files changed, 52 insertions(+), 8 deletions(-)
 create mode 100644 chain/actors/builtin/account/account.go
 create mode 100644 chain/actors/builtin/account/v0.go

diff --git a/chain/actors/builtin/account/account.go b/chain/actors/builtin/account/account.go
new file mode 100644
index 000000000..d4cbe4177
--- /dev/null
+++ b/chain/actors/builtin/account/account.go
@@ -0,0 +1,31 @@
+package account
+
+import (
+	"golang.org/x/xerrors"
+
+	"github.com/filecoin-project/go-address"
+	"github.com/filecoin-project/go-state-types/cbor"
+	v0builtin "github.com/filecoin-project/specs-actors/actors/builtin"
+
+	"github.com/filecoin-project/lotus/chain/actors/adt"
+	"github.com/filecoin-project/lotus/chain/types"
+)
+
+func Load(store adt.Store, act *types.Actor) (State, error) {
+	switch act.Code {
+	case v0builtin.AccountActorCodeID:
+		out := v0State{store: store}
+		err := store.Get(store.Context(), act.Head, &out)
+		if err != nil {
+			return nil, err
+		}
+		return &out, nil
+	}
+	return nil, xerrors.Errorf("unknown actor code %s", act.Code)
+}
+
+type State interface {
+	cbor.Marshaler
+
+	PubkeyAddress() (address.Address, error)
+}
diff --git a/chain/actors/builtin/account/v0.go b/chain/actors/builtin/account/v0.go
new file mode 100644
index 000000000..6001dd7bf
--- /dev/null
+++ b/chain/actors/builtin/account/v0.go
@@ -0,0 +1,16 @@
+package account
+
+import (
+	"github.com/filecoin-project/go-address"
+	"github.com/filecoin-project/lotus/chain/actors/adt"
+	"github.com/filecoin-project/specs-actors/actors/builtin/account"
+)
+
+type v0State struct {
+	account.State
+	store adt.Store
+}
+
+func (s *v0State) PubkeyAddress() (address.Address, error) {
+	return s.Address, nil
+}
diff --git a/chain/vm/vm.go b/chain/vm/vm.go
index 542dfee69..25c937ca3 100644
--- a/chain/vm/vm.go
+++ b/chain/vm/vm.go
@@ -23,10 +23,11 @@ import (
 	"github.com/filecoin-project/go-state-types/exitcode"
 	"github.com/filecoin-project/go-state-types/network"
 	"github.com/filecoin-project/specs-actors/actors/builtin"
-	"github.com/filecoin-project/specs-actors/actors/builtin/account"
 
 	"github.com/filecoin-project/lotus/build"
+	"github.com/filecoin-project/lotus/chain/actors/adt"
 	"github.com/filecoin-project/lotus/chain/actors/aerrors"
+	"github.com/filecoin-project/lotus/chain/actors/builtin/account"
 	"github.com/filecoin-project/lotus/chain/state"
 	"github.com/filecoin-project/lotus/chain/types"
 	"github.com/filecoin-project/lotus/lib/blockstore"
@@ -49,16 +50,12 @@ func ResolveToKeyAddr(state types.StateTree, cst cbor.IpldStore, addr address.Ad
 		return address.Undef, xerrors.Errorf("failed to find actor: %s", addr)
 	}
 
-	if act.Code != builtin.AccountActorCodeID {
-		return address.Undef, xerrors.Errorf("address %s was not for an account actor", addr)
-	}
-
-	var aast account.State
-	if err := cst.Get(context.TODO(), act.Head, &aast); err != nil {
+	aast, err := account.Load(adt.WrapStore(context.TODO(), cst), act)
+	if err != nil {
 		return address.Undef, xerrors.Errorf("failed to get account actor state for %s: %w", addr, err)
 	}
 
-	return aast.Address, nil
+	return aast.PubkeyAddress()
 }
 
 var _ cbor.IpldBlockstore = (*gasChargingBlocks)(nil)