fix(es/codegen): Emit override keyword (#8449)

**Description:**

Emits the `override` keyword.

crates/swc_ecma_codegen/src/lib.rs

@@ -1466,6 +1466,12 @@ where
                 formatting_space!();
             }
         }
+
+        if n.is_override {
+            keyword!("override");
+            space!()
+        }
+
         match n.kind {
             MethodKind::Method => {
                 if n.function.is_async {
@@ -1544,6 +1550,11 @@ where
             space!();
         }
 
+        if n.is_override {
+            keyword!("override");
+            space!()
+        }
+
         if n.readonly {
             keyword!("readonly");
             space!();
@@ -1590,15 +1601,18 @@ where
             emit!(dec)
         }
 
-        if n.accessibility != Some(Accessibility::Public) {
-            self.emit_accessibility(n.accessibility)?;
-        }
+        self.emit_accessibility(n.accessibility)?;
 
         if n.is_static {
             keyword!("static");
             space!();
         }
 
+        if n.is_override {
+            keyword!("override");
+            space!()
+        }
+
         if n.readonly {
             keyword!("readonly");
             space!()

crates/swc_ecma_codegen/tests/fixture/typescript/class_method/input.js

@@ -0,0 +1,4 @@
+class MyClass extends Base {
+    public override method(param: number): string {
+    }
+}

crates/swc_ecma_codegen/tests/fixture/typescript/class_method/output.js

@@ -0,0 +1,3 @@
+class MyClass extends Base {
+    public override method(param: number): string {}
+}

crates/swc_ecma_codegen/tests/fixture/typescript/class_method/output.min.js

@@ -0,0 +1 @@
+class MyClass extends Base{public override method(param:number):string{}}

crates/swc_ecma_codegen/tests/fixture/typescript/class_prop/input.js

@@ -1,8 +1,10 @@
-class MyClass {
+class MyClass extends Base {
     prop1?: string;
     prop2!: string;
     #prop3?: string;
     #prop4?: string = "test";
     static readonly prop5!: string;
     readonly #prop6 = "asdf";
+    public override readonly prop7 = 5;
+    override readonly #prop8 = 5;
 }

crates/swc_ecma_codegen/tests/fixture/typescript/class_prop/output.js

@@ -1,8 +1,10 @@
-class MyClass {
+class MyClass extends Base {
     prop1?: string;
     prop2!: string;
     #prop3?: string;
     #prop4?: string = "test";
     static readonly prop5!: string;
     readonly #prop6 = "asdf";
+    public override readonly prop7 = 5;
+    override readonly #prop8 = 5;
 }

crates/swc_ecma_codegen/tests/fixture/typescript/class_prop/output.min.js

@@ -1 +1 @@
-class MyClass{prop1?: string;prop2!: string;#prop3?: string;#prop4?: string="test";static readonly prop5!: string;readonly #prop6="asdf"}
+class MyClass extends Base{prop1?: string;prop2!: string;#prop3?: string;#prop4?: string="test";static readonly prop5!: string;readonly #prop6="asdf";public override readonly prop7=5;override readonly #prop8=5}

crates/swc_ecma_parser/tests/typescript/class/override/input.ts

@@ -0,0 +1,5 @@
+class C extends B {
+  override prop = 5;
+  override method() {
+  }
+}

crates/swc_ecma_parser/tests/typescript/class/override/input.ts.json

@@ -0,0 +1,131 @@
+{
+  "type": "Script",
+  "span": {
+    "start": 1,
+    "end": 69,
+    "ctxt": 0
+  },
+  "body": [
+    {
+      "type": "ClassDeclaration",
+      "identifier": {
+        "type": "Identifier",
+        "span": {
+          "start": 7,
+          "end": 8,
+          "ctxt": 0
+        },
+        "value": "C",
+        "optional": false
+      },
+      "declare": false,
+      "span": {
+        "start": 1,
+        "end": 69,
+        "ctxt": 0
+      },
+      "decorators": [],
+      "body": [
+        {
+          "type": "ClassProperty",
+          "span": {
+            "start": 23,
+            "end": 41,
+            "ctxt": 0
+          },
+          "key": {
+            "type": "Identifier",
+            "span": {
+              "start": 32,
+              "end": 36,
+              "ctxt": 0
+            },
+            "value": "prop",
+            "optional": false
+          },
+          "value": {
+            "type": "NumericLiteral",
+            "span": {
+              "start": 39,
+              "end": 40,
+              "ctxt": 0
+            },
+            "value": 5.0,
+            "raw": "5"
+          },
+          "typeAnnotation": null,
+          "isStatic": false,
+          "decorators": [],
+          "accessibility": null,
+          "isAbstract": false,
+          "isOptional": false,
+          "isOverride": true,
+          "readonly": false,
+          "declare": false,
+          "definite": false
+        },
+        {
+          "type": "ClassMethod",
+          "span": {
+            "start": 44,
+            "end": 67,
+            "ctxt": 0
+          },
+          "key": {
+            "type": "Identifier",
+            "span": {
+              "start": 53,
+              "end": 59,
+              "ctxt": 0
+            },
+            "value": "method",
+            "optional": false
+          },
+          "function": {
+            "params": [],
+            "decorators": [],
+            "span": {
+              "start": 44,
+              "end": 67,
+              "ctxt": 0
+            },
+            "body": {
+              "type": "BlockStatement",
+              "span": {
+                "start": 62,
+                "end": 67,
+                "ctxt": 0
+              },
+              "stmts": []
+            },
+            "generator": false,
+            "async": false,
+            "typeParameters": null,
+            "returnType": null
+          },
+          "kind": "method",
+          "isStatic": false,
+          "accessibility": null,
+          "isAbstract": false,
+          "isOptional": false,
+          "isOverride": true
+        }
+      ],
+      "superClass": {
+        "type": "Identifier",
+        "span": {
+          "start": 17,
+          "end": 18,
+          "ctxt": 0
+        },
+        "value": "B",
+        "optional": false
+      },
+      "isAbstract": false,
+      "typeParams": null,
+      "superTypeParams": null,
+      "implements": []
+    }
+  ],
+  "interpreter": null
+}

crates/swc_ecma_transforms/tests/fixture/legacy-only/issues/862/1/output.ts

@@ -1,10 +1,10 @@
 export class Product extends TimestampedEntity {
-    id!: string;
-    price!: number;
-    type!: ProductType;
-    productEntityId!: string;
-    /* ANCHOR: Relations ------------------------------------------------------ */ orders!: Order[];
-    discounts!: Discount[];
+    public id!: string;
+    public price!: number;
+    public type!: ProductType;
+    public productEntityId!: string;
+    /* ANCHOR: Relations ------------------------------------------------------ */ public orders!: Order[];
+    public discounts!: Discount[];
 }
 _ts_decorate([
     PrimaryGeneratedColumn("uuid")

crates/swc_ecma_transforms/tests/fixture/legacy-only/issues/862/2/output.ts

@@ -1,5 +1,5 @@
 export class Product extends TimestampedEntity {
-    id!: string;
+    public id!: string;
 }
 _ts_decorate([
     PrimaryGeneratedColumn("uuid")

crates/swc_ecma_transforms_typescript/src/strip_type.rs

@@ -137,6 +137,7 @@ impl VisitMut for StripType {
 
     fn visit_mut_class_method(&mut self, n: &mut ClassMethod) {
         n.accessibility = None;
+        n.is_override = false;
         n.visit_mut_children_with(self);
     }