stack: stacks should be applyable even if no components are (#35498)

internal/rpcapi/stacks_test.go

@@ -449,13 +449,13 @@ func TestStacksPlanStackChanges(t *testing.T) {
 				PlannedChange: &terraform1.PlannedChange{
 					Raw: []*anypb.Any{
 						mustMarshalAnyPb(&tfstackdata1.PlanApplyable{
-							Applyable: false,
+							Applyable: true,
 						}),
 					},
 					Descriptions: []*terraform1.PlannedChange_ChangeDescription{
 						{
 							Description: &terraform1.PlannedChange_ChangeDescription_PlanApplyable{
-								PlanApplyable: false,
+								PlanApplyable: true,
 							},
 						},
 					},

internal/stacks/stackruntime/plan.go

@@ -39,7 +39,7 @@ func Plan(ctx context.Context, req *PlanRequest, resp *PlanResponse) {
 		close(resp.PlannedChanges) // MUST be the last channel to close
 	}()
 
-	var errored, applyable bool
+	var errored bool
 
 	planTimestamp := time.Now().UTC()
 	if req.ForcePlanTimestamp != nil {
@@ -58,11 +58,6 @@ func Plan(ctx context.Context, req *PlanRequest, resp *PlanResponse) {
 	main.PlanAll(ctx, stackeval.PlanOutput{
 		AnnouncePlannedChange: func(ctx context.Context, change stackplan.PlannedChange) {
 			resp.PlannedChanges <- change
-			if componentChange, ok := change.(*stackplan.PlannedChangeComponentInstance); ok {
-				if componentChange.PlanApplyable {
-					applyable = true
-				}
-			}
 		},
 		AnnounceDiagnostics: func(ctx context.Context, diags tfdiags.Diagnostics) {
 			for _, diag := range diags {
@@ -82,9 +77,8 @@ func Plan(ctx context.Context, req *PlanRequest, resp *PlanResponse) {
 		resp.Diagnostics <- diag
 	}
 
-	// An overall stack plan is applyable if at least one of its component
-	// instances is applyable and we had no error diagnostics.
-	resp.Applyable = !errored && applyable
+	// An overall stack plan is applyable if it has no error diagnostics.
+	resp.Applyable = !errored
 
 	// Before we return we'll emit one more special planned change just to
 	// remember in the raw plan sequence whether we considered this plan to be

internal/stacks/stackruntime/plan_test.go

@@ -359,7 +359,7 @@ func TestPlanWithVariableDefaults(t *testing.T) {
 
 			wantChanges := []stackplan.PlannedChange{
 				&stackplan.PlannedChangeApplyable{
-					Applyable: false,
+					Applyable: true,
 				},
 				&stackplan.PlannedChangeHeader{
 					TerraformVersion: version.SemVer,
@@ -891,7 +891,7 @@ func TestPlanWithEphemeralInputVariables(t *testing.T) {
 
 		wantChanges := []stackplan.PlannedChange{
 			&stackplan.PlannedChangeApplyable{
-				Applyable: false,
+				Applyable: true,
 			},
 			&stackplan.PlannedChangeHeader{
 				TerraformVersion: version.SemVer,
@@ -949,7 +949,7 @@ func TestPlanWithEphemeralInputVariables(t *testing.T) {
 
 		wantChanges := []stackplan.PlannedChange{
 			&stackplan.PlannedChangeApplyable{
-				Applyable: false,
+				Applyable: true,
 			},
 			&stackplan.PlannedChangeHeader{
 				TerraformVersion: version.SemVer,
@@ -1008,7 +1008,7 @@ func TestPlanVariableOutputRoundtripNested(t *testing.T) {
 
 	wantChanges := []stackplan.PlannedChange{
 		&stackplan.PlannedChangeApplyable{
-			Applyable: false,
+			Applyable: true,
 		},
 		&stackplan.PlannedChangeHeader{
 			TerraformVersion: version.SemVer,
@@ -2145,7 +2145,7 @@ func TestPlanWithDeferredResource(t *testing.T) {
 
 	wantChanges := []stackplan.PlannedChange{
 		&stackplan.PlannedChangeApplyable{
-			Applyable: false,
+			Applyable: true,
 		},
 		&stackplan.PlannedChangeComponentInstance{
 			Addr: stackaddrs.Absolute(
@@ -2787,7 +2787,7 @@ func TestPlanWithDeferredEmbeddedStackForEach(t *testing.T) {
 
 	wantChanges := []stackplan.PlannedChange{
 		&stackplan.PlannedChangeApplyable{
-			Applyable: false,
+			Applyable: true,
 		},
 		&stackplan.PlannedChangeHeader{
 			TerraformVersion: version.SemVer,
@@ -2933,7 +2933,7 @@ func TestPlanWithDeferredEmbeddedStackAndComponentForEach(t *testing.T) {
 
 	wantChanges := []stackplan.PlannedChange{
 		&stackplan.PlannedChangeApplyable{
-			Applyable: false,
+			Applyable: true,
 		},
 		&stackplan.PlannedChangeHeader{
 			TerraformVersion: version.SemVer,
@@ -3140,7 +3140,7 @@ func TestPlanWithDeferredProviderForEach(t *testing.T) {
 
 	wantChanges := []stackplan.PlannedChange{
 		&stackplan.PlannedChangeApplyable{
-			Applyable: false,
+			Applyable: true,
 		},
 		&stackplan.PlannedChangeComponentInstance{
 			Addr: stackaddrs.Absolute(