diff --git a/protofsm/state_machine_test.go b/protofsm/state_machine_test.go
index 42e7a80d4..3dcb35099 100644
--- a/protofsm/state_machine_test.go
+++ b/protofsm/state_machine_test.go
@@ -321,12 +321,20 @@ func (d *dummyStateSpent) IsTerminal() bool {
 	return true
 }
 
-func assertState[Event any, Env Environment](t *testing.T,
-	m *StateMachine[Event, Env], expectedState State[Event, Env]) {
+// assertState asserts that the state machine is currently in the expected
+// state type and returns the state cast to that type.
+func assertState[Event any, Env Environment, S State[Event, Env]](t *testing.T,
+	m *StateMachine[Event, Env], expectedState S) S {
 
 	state, err := m.CurrentState()
 	require.NoError(t, err)
 	require.IsType(t, expectedState, state)
+
+	// Perform the type assertion to return the concrete type.
+	concreteState, ok := state.(S)
+	require.True(t, ok, "state type assertion failed")
+
+	return concreteState
 }
 
 func assertStateTransitions[Event any, Env Environment](
@@ -626,18 +634,15 @@ func TestStateMachineConfMapper(t *testing.T) {
 	assertStateTransitions(t, stateSub, expectedStates)
 
 	// Final state assertion.
-	finalState, err := stateMachine.CurrentState()
-	require.NoError(t, err)
-	require.IsType(t, &dummyStateConfirmed{}, finalState)
+	finalState := assertState(t, &stateMachine, &dummyStateConfirmed{})
 
 	// Assert that the details from the confirmation event were correctly
 	// propagated to the final state.
-	finalStateDetails := finalState.(*dummyStateConfirmed)
 	require.Equal(t,
-		*simulatedConf.BlockHash, finalStateDetails.blockHash,
+		*simulatedConf.BlockHash, finalState.blockHash,
 	)
 	require.Equal(t,
-		simulatedConf.BlockHeight, finalStateDetails.blockHeight,
+		simulatedConf.BlockHeight, finalState.blockHeight,
 	)
 
 	adapters.AssertExpectations(t)
@@ -706,18 +711,15 @@ func TestStateMachineSpendMapper(t *testing.T) {
 	assertStateTransitions(t, stateSub, expectedStates)
 
 	// Final state assertion.
-	finalState, err := stateMachine.CurrentState()
-	require.NoError(t, err)
-	require.IsType(t, &dummyStateSpent{}, finalState)
+	finalState := assertState(t, &stateMachine, &dummyStateSpent{})
 
 	// Assert that the details from the spend event were correctly
 	// propagated to the final state.
-	finalStateDetails := finalState.(*dummyStateSpent)
 	require.Equal(t,
-		*simulatedSpend.SpenderTxHash, finalStateDetails.spenderTxHash,
+		*simulatedSpend.SpenderTxHash, finalState.spenderTxHash,
 	)
 	require.Equal(t,
-		simulatedSpend.SpendingHeight, finalStateDetails.spendingHeight,
+		simulatedSpend.SpendingHeight, finalState.spendingHeight,
 	)
 
 	adapters.AssertExpectations(t)