Add 'fwplanmodifiers.NormalizeEmptyMap'.

internal/fwplanmodifiers/normalize_empty_map.go

@@ -0,0 +1,60 @@
+package fwplanmodifiers
+
+import (
+ "context"
+
+ "github.com/hashicorp/terraform-plugin-framework/tfsdk"
+ "github.com/hashicorp/terraform-plugin-framework/types"
+)
+
+type normalizeEmptyMap struct{}
+
+// NormalizeEmptyMap return an AttributePlanModifier that normalizes a missing Map.
+// Useful for resolving null vs. empty differences for resource tags.
+func NormalizeEmptyMap() tfsdk.AttributePlanModifier {
+ return normalizeEmptyMap{}
+}
+
+func (m normalizeEmptyMap) Description(context.Context) string {
+ return "Resolve differences between null and empty maps"
+}
+
+func (m normalizeEmptyMap) MarkdownDescription(ctx context.Context) string {
+ return m.Description(ctx)
+}
+
+func (m normalizeEmptyMap) Modify(ctx context.Context, request tfsdk.ModifyAttributePlanRequest, response *tfsdk.ModifyAttributePlanResponse) {
+ if request.AttributeState == nil {
+ response.AttributePlan = request.AttributePlan
+
+ return
+ }
+
+ // If the current value is semantically equivalent to the planned value
+ // then return the current value, else return the planned value.
+
+ var planned types.Map
+
+ response.Diagnostics = append(response.Diagnostics, tfsdk.ValueAs(ctx, request.AttributePlan, &planned)...)
+
+ if response.Diagnostics.HasError() {
+ return
+ }
+
+ var current types.Map
+
+ response.Diagnostics = append(response.Diagnostics, tfsdk.ValueAs(ctx, request.AttributeState, &current)...)
+
+ if response.Diagnostics.HasError() {
+ return
+ }
+
+ if planned.IsNull() && (current.IsNull() || len(current.Elems) == 0) ||
+ (current.IsNull() && (planned.IsNull() || len(planned.Elems) == 0)) {
+ response.AttributePlan = request.AttributeState
+
+ return
+ }
+
+ response.AttributePlan = request.AttributePlan
+}

internal/fwplanmodifiers/normalize_empty_map_test.go

@@ -0,0 +1,100 @@
+package fwplanmodifiers
+
+import (
+ "context"
+ "testing"
+
+ "github.com/google/go-cmp/cmp"
+ "github.com/hashicorp/terraform-plugin-framework/attr"
+ "github.com/hashicorp/terraform-plugin-framework/path"
+ "github.com/hashicorp/terraform-plugin-framework/tfsdk"
+ "github.com/hashicorp/terraform-plugin-framework/types"
+)
+
+func TestNormalizeEmptyMap(t *testing.T) {
+ t.Parallel()
+
+ type testCase struct {
+ plannedValue attr.Value
+ currentValue attr.Value
+ expectedValue attr.Value
+ expectError bool
+ }
+ tests := map[string]testCase{
+ "planned non-empty Map, current non-empty Map": {
+ plannedValue: types.Map{ElemType: types.StringType, Elems: map[string]attr.Value{
+ "2": types.String{Value: "TWO"},
+ }},
+ currentValue: types.Map{ElemType: types.StringType, Elems: map[string]attr.Value{
+ "1": types.String{Value: "ONE"},
+ }},
+ expectedValue: types.Map{ElemType: types.StringType, Elems: map[string]attr.Value{
+ "2": types.String{Value: "TWO"},
+ }},
+ },
+ "planned non-empty Map, current Null Map": {
+ plannedValue: types.Map{ElemType: types.StringType, Elems: map[string]attr.Value{
+ "2": types.String{Value: "TWO"},
+ }},
+ currentValue: types.Map{ElemType: types.StringType, Null: true},
+ expectedValue: types.Map{ElemType: types.StringType, Elems: map[string]attr.Value{
+ "2": types.String{Value: "TWO"},
+ }},
+ },
+ "planned Null Map, current non-empty Map": {
+ plannedValue: types.Map{ElemType: types.StringType, Null: true},
+ currentValue: types.Map{ElemType: types.StringType, Elems: map[string]attr.Value{
+ "1": types.String{Value: "ONE"},
+ }},
+ expectedValue: types.Map{ElemType: types.StringType, Null: true},
+ },
+ "planned empty Map, current Null Map": {
+ plannedValue: types.Map{ElemType: types.StringType, Elems: map[string]attr.Value{}},
+ currentValue: types.Map{ElemType: types.StringType, Null: true},
+ expectedValue: types.Map{ElemType: types.StringType, Null: true},
+ },
+ "planned Null Map, current empty Map": {
+ plannedValue: types.Map{ElemType: types.StringType, Null: true},
+ currentValue: types.Map{ElemType: types.StringType, Elems: map[string]attr.Value{}},
+ expectedValue: types.Map{ElemType: types.StringType, Elems: map[string]attr.Value{}},
+ },
+ "planned empty Map, current empty Map": {
+ plannedValue: types.Map{ElemType: types.StringType, Elems: map[string]attr.Value{}},
+ currentValue: types.Map{ElemType: types.StringType, Elems: map[string]attr.Value{}},
+ expectedValue: types.Map{ElemType: types.StringType, Elems: map[string]attr.Value{}},
+ },
+ "planned Null Map, current Null Map": {
+ plannedValue: types.Map{ElemType: types.StringType, Null: true},
+ currentValue: types.Map{ElemType: types.StringType, Null: true},
+ expectedValue: types.Map{ElemType: types.StringType, Null: true},
+ },
+ }
+
+ for name, test := range tests {
+ name, test := name, test
+ t.Run(name, func(t *testing.T) {
+ ctx := context.Background()
+ request := tfsdk.ModifyAttributePlanRequest{
+ AttributePath: path.Root("test"),
+ AttributePlan: test.plannedValue,
+ AttributeState: test.currentValue,
+ }
+ response := tfsdk.ModifyAttributePlanResponse{
+ AttributePlan: request.AttributePlan,
+ }
+ NormalizeEmptyMap().Modify(ctx, request, &response)
+
+ if !response.Diagnostics.HasError() && test.expectError {
+ t.Fatal("expected error, got no error")
+ }
+
+ if response.Diagnostics.HasError() && !test.expectError {
+ t.Fatalf("got unexpected error: %s", response.Diagnostics)
+ }
+
+ if diff := cmp.Diff(response.AttributePlan, test.expectedValue); diff != "" {
+ t.Errorf("unexpected diff (+wanted, -got): %s", diff)
+ }
+ })
+ }
+}