Prevent declaration of unused variables (#93)

* Only generate variables if AttrTypes value passed into template is non-empty (#92)

* Adding tests for ValueFromObject and ToTerraformValue when no attributes present (#92)

* Adding changelog entry (#92)

.changes/unreleased/BUG FIXES-20231122-070804.yaml

@@ -0,0 +1,5 @@
+kind: BUG FIXES
+body: 'schema: Prevent compilation errors due to the generation of unused variables'
+time: 2023-11-22T07:08:04.939979Z
+custom:
+  Issue: "93"

internal/schema/custom_nested_object_test.go

@@ -457,6 +457,23 @@ return ExampleValue{
 ExampleType: typeVal,
 state: attr.ValueStateKnown,
 }, diags
+}`),
+		},
+		"no-attributes": {
+			name: "Example",
+			expected: []byte(`
+func (t ExampleType) ValueFromObject(ctx context.Context, in basetypes.ObjectValue) (basetypes.ObjectValuable, diag.Diagnostics) {
+var diags diag.Diagnostics
+
+
+
+if diags.HasError() {
+return nil, diags
+}
+
+return ExampleValue{
+state: attr.ValueStateKnown,
+}, diags
 }`),
 		},
 	}
@@ -1410,6 +1427,35 @@ vals["type"] = val
 
 
 
+if err := tftypes.ValidateValue(objectType, vals); err != nil {
+return tftypes.NewValue(objectType, tftypes.UnknownValue), err
+}
+
+return tftypes.NewValue(objectType, vals), nil
+case attr.ValueStateNull:
+return tftypes.NewValue(objectType, nil), nil
+case attr.ValueStateUnknown:
+return tftypes.NewValue(objectType, tftypes.UnknownValue), nil
+default:
+panic(fmt.Sprintf("unhandled Object state in ToTerraformValue: %s", v.state))
+}
+}`),
+		},
+		"no-attributes": {
+			name: "Example",
+			expected: []byte(`func (v ExampleValue) ToTerraformValue(ctx context.Context) (tftypes.Value, error) {
+attrTypes := make(map[string]tftypes.Type, 0)
+
+
+
+objectType := tftypes.Object{AttributeTypes: attrTypes}
+
+switch v.state {
+case attr.ValueStateKnown:
+vals := make(map[string]tftypes.Value, 0)
+
+
+
 if err := tftypes.ValidateValue(objectType, vals); err != nil {
 return tftypes.NewValue(objectType, tftypes.UnknownValue), err
 }

internal/schema/templates/nested_object_type_value_from_object.gotmpl

@@ -2,7 +2,10 @@
 func (t {{.Name}}Type) ValueFromObject(ctx context.Context, in basetypes.ObjectValue) (basetypes.ObjectValuable, diag.Diagnostics) {
 var diags diag.Diagnostics
 
+{{- if .AttrValues}}
+
 attributes := in.Attributes()
+{{- end}}
 
 {{range $key, $value := .AttrValues }}
 {{$key.ToCamelCase}}Attribute, ok := attributes["{{$key}}"]

internal/schema/templates/nested_object_value_to_terraform_value.gotmpl

@@ -1,8 +1,11 @@
 func (v {{.Name}}Value) ToTerraformValue(ctx context.Context) (tftypes.Value, error) {
 attrTypes := make(map[string]tftypes.Type, {{len .AttrTypes}})
 
+{{- if .AttrTypes}}
+
 var val tftypes.Value
 var err error
+{{- end}}
 
 {{range $key, $value := .AttrTypes }}
 attrTypes["{{$key}}"] = {{$value}}.TerraformType(ctx)