fix(es/decorators): Fix metadata for accessors (#9444)

**Related issue:**
 - Closes https://github.com/swc-project/swc/issues/9435

.changeset/four-onions-wash.md

@@ -0,0 +1,6 @@
+---
+swc_ecma_transforms_proposal: patch
+swc_core: patch
+---
+
+fix(es/proposal): Metadata for accessor

crates/swc_ecma_transforms/tests/fixture/legacy-metadata/issues/9435/input.ts

@@ -0,0 +1,44 @@
+import { Entity, Column } from "typeorm";
+import { Field, ObjectType, registerEnumType } from "type-graphql";
+import { Enum1, Enum2 } from "./enum.js";
+
+export enum Enum3 {
+    A = "A",
+    B = "B",
+    C = "C",
+    D = "D",
+}
+
+registerEnumType(Enum3, { name: "Enum3" });
+
+@Entity("user", { schema: "public" })
+@ObjectType("User")
+export class User {
+    @Column({ name: "first_name" })
+    @Field({ nullable: true })
+    firstName?: string;
+
+    @Column({ name: "last_name" })
+    @Field({ nullable: true })
+    lastName?: string;
+
+    @Field()
+    get fullName(): string {
+        if (!this.firstName && !this.lastName) {
+            return "";
+        }
+        return `${this.firstName} ${this.lastName}`.trim();
+    }
+
+    @Column()
+    @Field(() => Enum1)
+    enum1: Enum1;
+
+    @Column()
+    @Field(() => Enum2)
+    enum2: Enum2;
+
+    @Column()
+    @Field(() => Enum3)
+    enum3: Enum3;
+}

crates/swc_ecma_transforms/tests/fixture/legacy-metadata/issues/9435/output.ts

@@ -0,0 +1,69 @@
+import { Entity, Column } from "typeorm";
+import { Field, ObjectType, registerEnumType } from "type-graphql";
+import { Enum1, Enum2 } from "./enum.js";
+export enum Enum3 {
+    A = "A",
+    B = "B",
+    C = "C",
+    D = "D"
+}
+registerEnumType(Enum3, {
+    name: "Enum3"
+});
+export class User {
+    firstName?: string;
+    lastName?: string;
+    get fullName(): string {
+        if (!this.firstName && !this.lastName) {
+            return "";
+        }
+        return `${this.firstName} ${this.lastName}`.trim();
+    }
+    enum1: Enum1;
+    enum2: Enum2;
+    enum3: Enum3;
+}
+_ts_decorate([
+    Column({
+        name: "first_name"
+    }),
+    Field({
+        nullable: true
+    }),
+    _ts_metadata("design:type", String)
+], User.prototype, "firstName", void 0);
+_ts_decorate([
+    Column({
+        name: "last_name"
+    }),
+    Field({
+        nullable: true
+    }),
+    _ts_metadata("design:type", String)
+], User.prototype, "lastName", void 0);
+_ts_decorate([
+    Field(),
+    _ts_metadata("design:type", String),
+    _ts_metadata("design:paramtypes", [])
+], User.prototype, "fullName", null);
+_ts_decorate([
+    Column(),
+    Field(()=>Enum1),
+    _ts_metadata("design:type", typeof Enum1 === "undefined" ? Object : Enum1)
+], User.prototype, "enum1", void 0);
+_ts_decorate([
+    Column(),
+    Field(()=>Enum2),
+    _ts_metadata("design:type", typeof Enum2 === "undefined" ? Object : Enum2)
+], User.prototype, "enum2", void 0);
+_ts_decorate([
+    Column(),
+    Field(()=>Enum3),
+    _ts_metadata("design:type", String)
+], User.prototype, "enum3", void 0);
+User = _ts_decorate([
+    Entity("user", {
+        schema: "public"
+    }),
+    ObjectType("User")
+], User);

crates/swc_ecma_transforms_proposal/src/decorators/legacy/metadata.rs

@@ -192,8 +192,25 @@ impl VisitMut for Metadata<'_> {
         }
 
         {
-            let dec = self
-                .create_metadata_design_decorator("design:type", quote_ident!("Function").as_arg());
+            let type_arg = match m.kind {
+                MethodKind::Method => quote_ident!("Function").as_arg(),
+                MethodKind::Getter => {
+                    let return_type = m.function.return_type.as_deref();
+
+                    if let Some(kind) = self.enums.get_kind_as_str(return_type) {
+                        quote_ident!(kind).as_arg()
+                    } else {
+                        serialize_type(self.class_name, return_type).as_arg()
+                    }
+                }
+                MethodKind::Setter => serialize_type(
+                    self.class_name,
+                    get_type_ann_of_pat(&m.function.params[0].pat),
+                )
+                .as_arg(),
+            };
+
+            let dec = self.create_metadata_design_decorator("design:type", type_arg);
             m.function.decorators.push(dec);
         }
         {
@@ -217,7 +234,9 @@ impl VisitMut for Metadata<'_> {
             );
             m.function.decorators.push(dec);
         }
-        {
+
+        // https://github.com/microsoft/TypeScript/blob/2a8865e6ba95c9bdcdb9e2c9c08f10c5f5c75391/src/compiler/transformers/ts.ts#L1180
+        if m.kind == MethodKind::Method {
             // Copy tsc behaviour
             // https://github.com/microsoft/TypeScript/blob/5e8c261b6ab746213f19ee3501eb8c48a6215dd7/src/compiler/transformers/typeSerializer.ts#L242
             let dec = self.create_metadata_design_decorator(