fix: fix apijson.Port for embedded structs (#3846)

Author: stainless-app[bot]

internal/apijson/port.go

@@ -36,14 +36,16 @@ func Port(from any, to any) error {
 
 	// Iterate through the fields of v and load all the "normal" fields in the struct to the map of
 	// string to reflect.Value, as well as their raw .JSON.Foo counterpart indicated by j.
-	var getFields func(t reflect.Type, v, j reflect.Value)
-	getFields = func(t reflect.Type, v, j reflect.Value) {
+	var getFields func(t reflect.Type, v reflect.Value)
+	getFields = func(t reflect.Type, v reflect.Value) {
+		j := v.FieldByName("JSON")
+
 		// Recurse into anonymous fields first, since the fields on the object should win over the fields in the
 		// embedded object.
 		for i := 0; i < t.NumField(); i++ {
 			field := t.Field(i)
 			if field.Anonymous {
-				getFields(field.Type, v.Field(i), v.FieldByName("JSON"))
+				getFields(field.Type, v.Field(i))
 				continue
 			}
 		}
@@ -60,7 +62,7 @@ func Port(from any, to any) error {
 			}
 		}
 	}
-	getFields(fromType, fromVal, fromJSON)
+	getFields(fromType, fromVal)
 
 	// Use the values from the previous step to populate the 'to' struct.
 	for i := 0; i < toType.NumField(); i++ {

internal/apijson/port_test.go

@@ -97,12 +97,15 @@ type CardMastercardData struct {
 type CommonFields struct {
 	Metadata Metadata `json:"metadata"`
 	Value    string   `json:"value"`
+
+	JSON commonFieldsJSON
 }
 
 type commonFieldsJSON struct {
 	Metadata    Field
 	Value       Field
 	ExtraFields map[string]Field
+	raw         string
 }
 
 type CardEmbedded struct {
@@ -115,7 +118,6 @@ type CardEmbedded struct {
 }
 
 type cardEmbeddedJSON struct {
-	commonFieldsJSON
 	Processor   Field
 	Data        Field
 	IsFoo       Field
@@ -196,18 +198,19 @@ var portTests = map[string]struct {
 					CreatedAt: "Mar 29 2024",
 				},
 				Value: "embedded_value",
+				JSON: commonFieldsJSON{
+					Metadata: Field{raw: `{"created_at":"Mar 29 2024"}`, status: valid},
+					Value:    Field{raw: `"embedded_value"`, status: valid},
+					raw:      `should not matter`,
+				},
 			},
 			Processor: "visa",
 			IsFoo:     true,
 			Data: CardVisaData{
 				Foo: "embedded_foo",
 			},
 			JSON: cardEmbeddedJSON{
-				commonFieldsJSON: commonFieldsJSON{
-					Metadata: Field{raw: `{"created_at":"Mar 29 2024"}`, status: valid},
-					Value:    Field{raw: `"embedded_value"`, status: valid},
-				},
-				raw:       `{"processor":"visa","is_foo":true,"data":{"foo":"embedded_foo"}}`,
+				raw:       `{"processor":"visa","is_foo":true,"data":{"foo":"embedded_foo"},"metadata":{"created_at":"Mar 29 2024"},"value":"embedded_value"}`,
 				Processor: Field{raw: `"visa"`, status: valid},
 				IsFoo:     Field{raw: `true`, status: valid},
 				Data:      Field{raw: `{"foo":"embedded_foo"}`, status: valid},
@@ -225,7 +228,7 @@ var portTests = map[string]struct {
 			},
 			Value: "embedded_value",
 			JSON: cardJSON{
-				raw:       "{\"processor\":\"visa\",\"is_foo\":true,\"data\":{\"foo\":\"embedded_foo\"}}",
+				raw:       `{"processor":"visa","is_foo":true,"data":{"foo":"embedded_foo"},"metadata":{"created_at":"Mar 29 2024"},"value":"embedded_value"}`,
 				Processor: Field{raw: `"visa"`, status: 0x3},
 				IsFoo:     Field{raw: "true", status: 0x3},
 				Data:      Field{raw: `{"foo":"embedded_foo"}`, status: 0x3},