design:type wrong for enum values

[hcesar]

Describe the bug
In TSC, when you have an enum type, the base enum type is set as design:type.
SWC is setting the enum object itself.

Input code

enum MyEnum {
  x = "xxx",
  y = "yyy"
}

class Xpto {
  @Decorator()
  value!: MyEnum;
}

function Decorator() {
  return function (...args) {};
}

Config

{
  "module": {
    "type": "commonjs"
  },
  "jsc": {
    "target": "es2018",
    "parser": {
      "syntax": "typescript",
      "decorators": true,
      "dynamicImport": false
    },
    "transform": {
      "legacyDecorator": false,
      "decoratorMetadata": true
    }
  }
}

Expected behavior
A clear and concise description of what you expected to happen.

TSC:

__decorate([
    Decorator(),
    __metadata("design:type", String)
], Xpto.prototype, "value", void 0);

SWC:

Reflect.metadata("design:type", typeof MyEnum === "undefined" ? Object : MyEnum)

[Exilz]

@kdy1 Any news regarding this issue ? We have a similar problem that's preventing our team from switching to swc. We're using https://github.com/RobinBuschmann/sequelize-typescript and decorators are a problem for us right now.

@Column
status: TProcessingStates;

TSC:

__decorate([
    decorators_1.Groups([{ operation: 'read' }, { operation: 'write' }]),
    sequelize_typescript_1.Column,
    __metadata("design:type", String)
], Collage.prototype, "status", void 0);

SWC:

Reflect.metadata("design:type", typeof _mediaManager.TProcessingStates === "undefined" ? Object : _mediaManager.TProcessingStates)

Switching to swc would be a game changer for our team.

[kdy1]

@Exilz I'll fix this soon.

I expect today or tomorrow (It's almost 11 PM here, so...)

[kdy1]

Fixed it.

May I list your company on the site as swc user after the migration?

[Exilz]

@kdy1 I need to ask the CEO permission but I guess we'd be happy to be listed on the website !
How do I go about testing your fix ? Do I need to build the source myself ? I've never used rust before so I'm not sure where to start.

EDIT: nevermind, I just realized you have a CI that's compiling it right now.

[kdy1]

@Exilz I'm now in progress of publishing. Github actions will publish new version.
Typically it takes about one hour.

Oh. I noticed that github updates comments real-time.

[Exilz]

@kdy1 thanks a lot for the update. I'm still in the process of refactoring our code, but it looks like we're one step closer to migrating to swc.

However, I noticed a couple of things :

• Using enums as the issue stated, it doesn't work if the enum is imported from another file. It compiles properly when the enum is declared in the same file, though.

import { TPublicationStatus } from '../publicationStatus'; 

class MyClass {

  @Column
   publicationStatus: TPublicationStatus;
}

which compiles to

_dec31 = typeof Reflect !== "undefined" && typeof Reflect.metadata === "function" && Reflect.metadata("design:type", typeof _publicationStatus.TPublicationStatus === "undefined" ? Object : _publicationStatus.TPublicationStatus)

• A kind of related issue happens using types instead of enums, as in the following exemple :

    @Column
    type: 'reps' | 'time';

which compiles to

 _dec24 = typeof Reflect !== "undefined" && typeof Reflect.metadata === "function" && Reflect.metadata("design:type", void 0)

This is also true when declaring the type separately and not directly in the class.

Should I open a new issue ? Or two ?

[kdy1]

I'll just reopen this.
But I'm not sure if knowing a type is enum without evaluating dependencies.
(tsc works by loading all file, while swc and babel work in one-by-one manner)

Evaluating deps is not hard, but I'm not sure about the api change.