Referencing Decorated Class in Parameter-Decorator #1278
Description
Describe the bug
If the decorated class is referenced in a parameter-decorator, swc produced an "invalid" output. The output tries to access the class before it's initialized causing the following error message: ReferenceError: Cannot access 'MyClass' before initialization
Input code
type Klass<T = any> = {new (...args: any[]): T};
function MyDecorator(klass: Klass): PropertyDecorator {
return () => {
// do something
console.log(klass);
}
}
class MyClass {
@MyDecorator(MyClass) prop: '';
}
console.log(new MyClass());Config
{
"jsc": {
"parser": {
"syntax": "typescript",
"tsx": false,
"decorators": true,
"dynamicImport": false
},
"externalHelpers": false,
"target": "es2020",
"loose": true,
"transform": {
"legacyDecorator": false,
"decoratorMetadata": true
}
},
"module": {
"type": "commonjs",
"strictMode": true
}
}Expected behavior
Compiling the same code with tsc --experimentalDecorators true -t ES2020 yields the following result:
var __decorate // ...
function MyDecorator(klass) {
return ()=>{
// do something
console.log(klass);
};
}
class MyClass {
}
__decorate([
MyDecorator(MyClass)
], MyClass.prototype, "prop", void 0);
console.log(new MyClass());SWC Output
This is (part of) the code, swc outputs:
function _applyDecoratedDescriptor(target, property, decorators, descriptor, context) {/* ... */}
function _initializerDefineProperty(target, property, descriptor, context) {/* ... */}
var _class, _descriptor;
function MyDecorator(klass) {
return ()=>{
// do something
console.log(klass);
};
}
// here, the class is accessed
var _dec = MyDecorator(MyClass), _dec1 = typeof Reflect !== "undefined" && typeof Reflect.metadata === "function" && Reflect.metadata("design:type", String);
let MyClass = ((_class = function() {
class MyClass1 {
constructor(){
_initializerDefineProperty(this, "prop", _descriptor, this);
}
}
return MyClass1;
}()) || _class, _descriptor = _applyDecoratedDescriptor(_class.prototype, "prop", [
_dec,
_dec1
], {
configurable: true,
enumerable: true,
writable: true,
initializer: void 0
}), _class);
console.log(new MyClass());Version
The version of @swc/core: 1.2.40