diff --git a/storage/sector_2.go b/storage/sector_fsm.go
similarity index 100%
rename from storage/sector_2.go
rename to storage/sector_fsm.go
diff --git a/storage/sectors_fsm_test.go b/storage/sectors_fsm_test.go
new file mode 100644
index 000000000..115a928b5
--- /dev/null
+++ b/storage/sectors_fsm_test.go
@@ -0,0 +1,79 @@
+package storage
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+
+	"github.com/filecoin-project/lotus/api"
+	"github.com/filecoin-project/lotus/lib/statemachine"
+)
+
+func (t *test) planSingle(evt interface{}) {
+	_, err := t.m.plan([]statemachine.Event{{evt}}, t.state)
+	require.NoError(t.t, err)
+}
+
+type test struct {
+	m     *Miner
+	t     *testing.T
+	state *SectorInfo
+
+	next func(statemachine.Context, SectorInfo) error
+}
+
+func TestHappyPath(t *testing.T) {
+	m := test{
+		m:     &Miner{},
+		t:     t,
+		state: &SectorInfo{State: api.Packing},
+	}
+
+	m.planSingle(SectorPacked{})
+	require.Equal(m.t, m.state.State, api.Unsealed)
+
+	m.planSingle(SectorSealed{})
+	require.Equal(m.t, m.state.State, api.PreCommitting)
+
+	m.planSingle(SectorPreCommitted{})
+	require.Equal(m.t, m.state.State, api.PreCommitted)
+
+	m.planSingle(SectorSeedReady{})
+	require.Equal(m.t, m.state.State, api.Committing)
+
+	m.planSingle(SectorCommitted{})
+	require.Equal(m.t, m.state.State, api.CommitWait)
+
+	m.planSingle(SectorProving{})
+	require.Equal(m.t, m.state.State, api.Proving)
+}
+
+func TestSeedRevert(t *testing.T) {
+	m := test{
+		m:     &Miner{},
+		t:     t,
+		state: &SectorInfo{State: api.Packing},
+	}
+
+	m.planSingle(SectorPacked{})
+	require.Equal(m.t, m.state.State, api.Unsealed)
+
+	m.planSingle(SectorSealed{})
+	require.Equal(m.t, m.state.State, api.PreCommitting)
+
+	m.planSingle(SectorPreCommitted{})
+	require.Equal(m.t, m.state.State, api.PreCommitted)
+
+	m.planSingle(SectorSeedReady{})
+	require.Equal(m.t, m.state.State, api.Committing)
+
+	_, err := m.m.plan([]statemachine.Event{{SectorSeedReady{}}, {SectorCommitted{}}}, m.state)
+	require.NoError(t, err)
+	require.Equal(m.t, m.state.State, api.Committing)
+
+	m.planSingle(SectorCommitted{})
+	require.Equal(m.t, m.state.State, api.CommitWait)
+
+	m.planSingle(SectorProving{})
+	require.Equal(m.t, m.state.State, api.Proving)
+}