properly handle actions without config

internal/plans/action_invocation.go

@@ -34,25 +34,31 @@ type ActionInvocationInstance struct {
 // serialized so it can be written to a plan file. Pass the implied type of the
 // corresponding resource type schema for correct operation.
 func (ai *ActionInvocationInstance) Encode(schema *providers.ActionSchema) (*ActionInvocationInstanceSrc, error) {
-	ty := cty.DynamicPseudoType
-	if schema != nil {
-		ty = schema.ConfigSchema.ImpliedType()
-	}
-
-	configValue, err := NewDynamicValue(ai.ConfigValue, ty)
-	if err != nil {
-		return nil, err
-	}
 
-	return &ActionInvocationInstanceSrc{
+	ret := &ActionInvocationInstanceSrc{
 		Addr:                    ai.Addr,
 		TriggeringResourceAddr:  ai.TriggeringResourceAddr,
 		TriggerEvent:            ai.TriggerEvent,
 		ActionTriggerBlockIndex: ai.ActionTriggerBlockIndex,
 		ActionsListIndex:        ai.ActionsListIndex,
 		ProviderAddr:            ai.ProviderAddr,
-		ConfigValue:             configValue,
-	}, nil
+	}
+
+	if ai.ConfigValue != cty.NilVal {
+		ty := cty.DynamicPseudoType
+		if schema != nil {
+			ty = schema.ConfigSchema.ImpliedType()
+		}
+
+		var err error
+		ret.ConfigValue, err = NewDynamicValue(ai.ConfigValue, ty)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	return ret, nil
+
 }
 
 type ActionInvocationInstances []*ActionInvocationInstance

internal/plans/planfile/tfplan.go

@@ -1291,11 +1291,13 @@ func actionInvocationFromTfplan(rawAction *planproto.ActionInvocationInstance) (
 	}
 	ret.ProviderAddr = providerAddr
 
-	configVal, err := valueFromTfplan(rawAction.ConfigValue)
-	if err != nil {
-		return nil, fmt.Errorf("invalid config value: %s", err)
+	if rawAction.ConfigValue != nil {
+		configVal, err := valueFromTfplan(rawAction.ConfigValue)
+		if err != nil {
+			return nil, fmt.Errorf("invalid config value: %s", err)
+		}
+		ret.ConfigValue = configVal
 	}
-	ret.ConfigValue = configVal
 
 	return ret, nil
 }
@@ -1320,7 +1322,6 @@ func actionInvocationToTfPlan(action *plans.ActionInvocationInstanceSrc) (*planp
 	case configs.AfterDestroy:
 		triggerEvent = planproto.ActionTriggerEvent_AFTER_DESTROY
 	}
-	configValue := valueToTfplan(action.ConfigValue)
 
 	ret := &planproto.ActionInvocationInstance{
 		Addr:                    action.Addr.String(),
@@ -1329,7 +1330,11 @@ func actionInvocationToTfPlan(action *plans.ActionInvocationInstanceSrc) (*planp
 		ActionsListIndex:        int64(action.ActionsListIndex),
 		ActionTriggerBlockIndex: int64(action.ActionTriggerBlockIndex),
 		TriggerEvent:            triggerEvent,
-		ConfigValue:             configValue,
 	}
+
+	if action.ConfigValue != nil {
+		ret.ConfigValue = valueToTfplan(action.ConfigValue)
+	}
+
 	return ret, nil
 }

internal/plans/planfile/tfplan_test.go

@@ -316,6 +316,21 @@ func examplePlanForTest(t *testing.T) *plans.Plan {
 						Name: "woot",
 					}.Instance(addrs.IntKey(0)).Absolute(addrs.RootModuleInstance),
 				},
+				{
+					Addr:                    addrs.Action{Type: "example", Name: "bar"}.Instance(addrs.NoKey).Absolute(addrs.RootModuleInstance),
+					ProviderAddr:            provider,
+					TriggerEvent:            configs.BeforeCreate,
+					ActionTriggerBlockIndex: 2,
+					ActionsListIndex:        1,
+					TriggeringResourceAddr: addrs.Resource{
+						Mode: addrs.ManagedResourceMode,
+						Type: "test_thing",
+						Name: "woot",
+					}.Instance(addrs.IntKey(0)).Absolute(addrs.RootModuleInstance),
+					ConfigValue: mustNewDynamicValue(cty.ObjectVal(map[string]cty.Value{
+						"id": cty.StringVal("testing"),
+					}), objTy),
+				},
 			},
 		},
 		DriftedResources: []*plans.ResourceInstanceChangeSrc{