Remove mock for Versions interface (#3312)

scripts/mocks.mockgen.txt

@@ -29,7 +29,7 @@ github.com/ava-labs/avalanchego/vms/avm/txs/mempool=Mempool=vms/avm/txs/mempool/
 github.com/ava-labs/avalanchego/vms/components/avax=TransferableIn=vms/components/avax/mock_transferable_in.go
 github.com/ava-labs/avalanchego/vms/components/verify=Verifiable=vms/components/verify/mock_verifiable.go
 github.com/ava-labs/avalanchego/vms/platformvm/block=Block=vms/platformvm/block/mock_block.go
-github.com/ava-labs/avalanchego/vms/platformvm/state=Chain,Diff,State,Versions=vms/platformvm/state/mock_state.go
+github.com/ava-labs/avalanchego/vms/platformvm/state=Chain,Diff,State=vms/platformvm/state/mock_state.go
 github.com/ava-labs/avalanchego/vms/platformvm/state=StakerIterator=vms/platformvm/state/mock_staker_iterator.go
 github.com/ava-labs/avalanchego/vms/platformvm/txs/mempool=Mempool=vms/platformvm/txs/mempool/mock_mempool.go
 github.com/ava-labs/avalanchego/vms/platformvm/utxo=Verifier=vms/platformvm/utxo/mock_verifier.go

vms/platformvm/state/diff_test.go

@@ -22,15 +22,15 @@ import (
 	"github.com/ava-labs/avalanchego/vms/platformvm/txs"
 )
 
-func TestDiffMissingState(t *testing.T) {
-	ctrl := gomock.NewController(t)
+type nilStateGetter struct{}
 
-	versions := NewMockVersions(ctrl)
+func (nilStateGetter) GetState(ids.ID) (Chain, bool) {
+	return nil, false
+}
 
+func TestDiffMissingState(t *testing.T) {
 	parentID := ids.GenerateTestID()
-	versions.EXPECT().GetState(parentID).Times(1).Return(nil, false)
-
-	_, err := NewDiff(parentID, versions)
+	_, err := NewDiff(parentID, nilStateGetter{})
 	require.ErrorIs(t, err, ErrMissingParentState)
 }
 
@@ -587,16 +587,9 @@ func TestDiffSubnetOwner(t *testing.T) {
 }
 
 func TestDiffSubnetManager(t *testing.T) {
-	require := require.New(t)
-	ctrl := gomock.NewController(t)
-
-	state := newTestState(t, memdb.New())
-
-	states := NewMockVersions(ctrl)
-	lastAcceptedID := ids.GenerateTestID()
-	states.EXPECT().GetState(lastAcceptedID).Return(state, true).AnyTimes()
-
 	var (
+		require    = require.New(t)
+		state      = newTestState(t, memdb.New())
 		newManager = chainIDAndAddr{ids.GenerateTestID(), []byte{1, 2, 3, 4}}
 		subnetID   = ids.GenerateTestID()
 	)
@@ -606,7 +599,7 @@ func TestDiffSubnetManager(t *testing.T) {
 	require.Equal(ids.Empty, chainID)
 	require.Nil(addr)
 
-	d, err := NewDiff(lastAcceptedID, states)
+	d, err := NewDiffOn(state)
 	require.NoError(err)
 
 	chainID, addr, err = d.GetSubnetManager(subnetID)