minifier removes too much code, leaving variable undefined

[mischnic]

Describe the bug

The minified removes too much code

Input code

var $eb2fd35624c84372$exports = {};
var $eb2fd35624c84372$var$__esDecorate = $eb2fd35624c84372$exports && $eb2fd35624c84372$exports.__esDecorate || function(ctor, descriptorIn, decorators, contextIn, initializers, extraInitializers) {
    function accept(f) {
        if (f !== void 0 && typeof f !== "function") throw new TypeError("Function expected");
        return f;
    }
    var kind = contextIn.kind, key = kind === "getter" ? "get" : kind === "setter" ? "set" : "value";
    var target = !descriptorIn && ctor ? contextIn["static"] ? ctor : ctor.prototype : null;
    var descriptor = descriptorIn || (target ? Object.getOwnPropertyDescriptor(target, contextIn.name) : {});
    var _, done = false;
    for(var i = decorators.length - 1; i >= 0; i--){
        var context = {};
        for(var p in contextIn)context[p] = p === "access" ? {} : contextIn[p];
        for(var p in contextIn.access)context.access[p] = contextIn.access[p];
        context.addInitializer = function(f) {
            if (done) throw new TypeError("Cannot add initializers after decoration has completed");
            extraInitializers.push(accept(f || null));
        };
        var result = (0, decorators[i])(kind === "accessor" ? {
            get: descriptor.get,
            set: descriptor.set
        } : descriptor[key], context);
        if (kind === "accessor") {
            if (result === void 0) continue;
            if (result === null || typeof result !== "object") throw new TypeError("Object expected");
            if (_ = accept(result.get)) descriptor.get = _;
            if (_ = accept(result.set)) descriptor.set = _;
            if (_ = accept(result.init)) initializers.unshift(_);
        } else if (_ = accept(result)) {
            if (kind === "field") initializers.unshift(_);
            else descriptor[key] = _;
        }
    }
    if (target) Object.defineProperty(target, contextIn.name, descriptor);
    done = true;
};
var $eb2fd35624c84372$var$__runInitializers = $eb2fd35624c84372$exports && $eb2fd35624c84372$exports.__runInitializers || function(thisArg, initializers, value) {
    var useValue = arguments.length > 2;
    for(var i = 0; i < initializers.length; i++)value = useValue ? initializers[i].call(thisArg, value) : initializers[i].call(thisArg);
    return useValue ? value : void 0;
};
Symbol.metadata ??= Symbol("Symbol.metadata");
const $eb2fd35624c84372$var$CustomElement = (tag)=>{
    return (ctor, context)=>{
        context.addInitializer(function() {
            customElements.define(tag, this);
            console.log("metadata:", context.metadata);
        });
        return ctor;
    };
};
let $eb2fd35624c84372$var$A = (()=>{
    let _classDecorators = [
        $eb2fd35624c84372$var$CustomElement("component-a")
    ];
    let _classDescriptor;
    let _classExtraInitializers = [];
    let _classThis;
    let _classSuper = HTMLElement;
    var A = class extends _classSuper {
        static{
            _classThis = this;
        }
        static{
            const _metadata = typeof Symbol === "function" && Symbol.metadata ? Object.create(_classSuper[Symbol.metadata] ?? null) : void 0;
            $eb2fd35624c84372$var$__esDecorate(null, _classDescriptor = {
                value: _classThis
            }, _classDecorators, {
                kind: "class",
                name: _classThis.name,
                metadata: _metadata
            }, null, _classExtraInitializers);
            A = _classThis = _classDescriptor.value;
            if (_metadata) Object.defineProperty(_classThis, Symbol.metadata, {
                enumerable: true,
                configurable: true,
                writable: true,
                value: _metadata
            });
            $eb2fd35624c84372$var$__runInitializers(_classThis, _classExtraInitializers);
        }
        constructor(){
            super();
            this.innerHTML = "Component A is working";
        }
    };
    return A = _classThis;
})();
console.log(new $eb2fd35624c84372$var$A().tagName);

Config

const config = {
  jsc: {
    target: "es2022",
    minify: {
      mangle: true,
      compress: true,
      toplevel: false,
      module: false,
    },
  },
  minify: true,
  sourceMaps: false,
  configFile: false,
  swcrc: false,
};

await swc.transform(fs.readFileSync(input, "utf8"), config);

Playground link (or link to the minimal reproduction)

https://play.swc.rs/?version=1.3.94-nightly-20231016.1&code=H4sIAAAAAAAAA6VXbW%2FbNhD%2B7l%2FBakEhoY6apt1L7DlGkWZYgXYd1mxfjMBgZMpWK5MCSeWlqf9770RSol6cBJgCxBbveHd87rk7%2BppKcsCujtPV659%2FOX6T%2FPbm9a%2FHB%2By2EFIrMiP3u%2BnoelAHVg%2BWS6besURIqhko7zf0%2FPl%2BYdyy8v07SUue6EzwMNFCjsmKqURmBXx%2Fz%2FGtUhRSjUkiuGa3GpcznumM5tk3hgJYlPS9txSR%2BxGBx5kmNElYocPUCfDJUhKm5NlsRq5FtiJHGLW%2BK5hIiVkO3PYgInojxQ3h7IZcgMq5lEKGwR%2FOPByNJZqtgmham5dMl5KT1Kzsqv8I7deMrwC8%2BjAxLozJV3YHq0aIvtdMayYDMq%2B%2BBmTiyVQjU0YWXNO8ZMG09qKphG1g8ZmPJx4RUYadtf9FoDTVWRJc4ioKJ9VHXEihBQICC7zM88Z4YxIctOxDOkPrek4%2BXX0BVGJ4%2BXTD%2F5aiYFLfvavVraKX15jTLYvA3f0uarwtgQWCI%2BFSmitmBCnsR2FWReA4EueMr%2FWGHJJXUxCdzsgRfB4eRk3WcZN1aPnuJM5kAexqYorst0VxCfqFSQDSSSlMwP0O4aqxLC4fsxebvc6sfTXWu0otc%2FWG1cqjOqLi6qfFbsdwhG4Pfc8o50ITMNiqJ0JTYJdDFem9oQrcb4ucdTiOT6%2F44qJUm9BVHFIC2RN52zzQESDJVJljNsIjv%2BAX2WUUNqQ3kIiK9u1jAokmHg2RcOOWguoowHsTC%2FFFCyjDy5qRXsgI5UAsQ4i749SNJarsZbxk04eUESVEy%2FYgK6kakagqaV8bMnU22IScmyWgazNi7CJIUdRBDZSWT9mrunvV0%2Fci02CzT7i45GqTpTpc%2BhwhDIp92Eg0BHuTnTRjOaDwuI%2BKvuilQ4D2WXZeA0dHpm1Frr2tWJpx5trbnqbmjzUbgO1pWiItHhm7suR%2Bhf2f2ds15Q9gvcnUW7nujtdqtjjIMcxSsf9wDfMi1%2BWWcV233lNy3O%2FQ2IXJ7%2B2EGH0QvHgRXVtrteF5Sxc6QZzQPG8CtCFNHlSzQNtB7Nk27ia2PCv0P99tr0Qeb5mmK6opmc9nxKyFQUeG9QXZVXpPus5KpcX2PGeIC3Y1TdfR7PTeD8bedVyfcVJ8hvt8WCepy%2F3Ed6csHdHnmCAOHbpj4CJncS7WYeBONAnqUOpT%2BqXYv9Vg%2BPZiU8EHk2EPGm8RgbA%2BISouk5wqdwUUFZ0XtYMnYBoGOIygfLg%2BhGxUW%2B2g9M27eutKzrsDC%2F339l8Adt21z2VRTdw%2FLz5%2BsLE01xQ8aKWFE5HxlWptanJmblvtHDYusSPUnpu%2Bs2%2Bj4eGypu3MTQ%2FDWdsP3TUWe0OP6K6PJZLBhTz0gl50dOGCODez3KsdP5rHfzWEuH3cSxHexFqWDKhQpRMPm5bGbtzj0XjACE4FuB5XmsG4J8be7LswzbqnVhdKA3U3GP9gPYZ1ihCp0kp5F4%2B4OvvAOK2rc8%2F0aayOu5keQodxaN6SXuUAAg6i%2FsmBYGm2Lh%2FUuZGZfkjuEjkMXfQ0DnXmVuukj6PeVFFVMbLEBhZGbUQUkj7sxIPVCJcWziRWPeQqOHPNB%2FII2bsREki2DnoXhtb0aaccemYU2jHiujFe6va00DCKoZ%2F%2FhT%2BOpqPR6OXLn4gSpUzYR1oU4Pvffz7MgOfsNj6hJ6%2Fg7yT%2BouItLUY%2FADpmou3wDwAA&config=H4sIAAAAAAAAA32UO5LbMAxA%2Bz2FR3WKjIsUOUC6nIFDi6BMhyQ0BOi1Zsd3D%2FTzeteQOgkPP%2BL38XY4NBdqm9%2BHD%2FmUn94WgvL4FwkNme1NJA20yVJbQs%2FNj5VeaETeRoJJdJ9JExEJVrLIUsjBD8%2B%2BW0x9AaInmUht6WqCzPTVfmEF30fApT7LT4gRbN4hxpIJmaGDojluMUbbE5irLYqXMVNbAqEWYoSVwZm%2BYK%2Fy7AIHzBLzlTqwzrToQEGhQMvhCpqZxBKzTPI85T0TdnCqXTf185s1XG2slpWYcJtaItkqXs8YiI2vWSvhDDdqMMOluN8tgzcFuJb8anfBkDd68g9AKhAtUbYJNL%2BThpd52rL2u5YhexlZHhQu8629MkMnRTUheKWyY2WgcNC6WcDVFsbKtlo6C94oHwUHBryXWVFc03vg9qwF5aEH9AqQ%2FlqvTdUMzGMLN%2Fi4EDv4j7yS9QFbNJLl8zalIZ0w7gRIwGd0OwrSCsZtXORK3PptXrMDGQ1wqkqlCbweAVkARhOBtdmQ9RCPpot4%2BjwTi8L9cW%2BTzd3nvn85uSxzPrlugI4%2Fj8fmbWFNQlcno%2BXIj32f9X49Ka3Xec2sCfR3NZxyuf8Hw%2FodQi8GAAA%3D

SWC Info output

1.3.94-nightly-20231016.1

Expected behavior

Still works afterwards

Actual behavior

The class is gone and _classThis undefined

let _classThis;
var $eb2fd35624c84372$exports = {};
$eb2fd35624c84372$exports && $eb2fd35624c84372$exports.__esDecorate,
  $eb2fd35624c84372$exports && $eb2fd35624c84372$exports.__runInitializers,
  (Symbol.metadata ??= Symbol("Symbol.metadata")),
  console.log(new (HTMLElement, _classThis)().tagName);

Version

1.3.94-nightly-20231016.1

Additional context

swc fails to minify what tsc outputs for

// @ts-ignore assign to readonly property as polyfill
Symbol.metadata ??= Symbol("Symbol.metadata");

const CustomElement = (tag: string) => {
  return <T extends new () => HTMLElement>(ctor: T, context: ClassDecoratorContext<T>) => {
    context.addInitializer(function () {
      customElements.define(tag, this);
      console.log("metadata:", context.metadata);
    });
    return ctor;
  };
};

@CustomElement("component-a")
class A extends HTMLElement {
  constructor() {
    super();
    this.innerHTML = "Component A is working";
  }
}

console.log(new A().tagName);

parcel-bundler/parcel#9219

[swc-bot]

This closed issue has been automatically locked because it had no new activity for a month. If you are running into a similar issue, please create a new issue with the steps to reproduce. Thank you.