swc: design:type wrong for enum values

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)

About this issue

Original URL
State: closed
Created 4 years ago
Reactions: 8
Comments: 37 (14 by maintainers)

Commits related to this issue

fix: Decorator metadata (#1248) swc_ecma_transforms: - Emit proper typename for `design:type` used with enum. (#1160) — committed to swc-project/swc by kdy1 4 years ago
Add a test for #1160 — committed to kdy1/swc by kdy1 3 years ago
Fix #1160 — committed to kdy1/swc by kdy1 3 years ago
Add an integration test for #1160 — committed to kdy1/swc by kdy1 3 years ago

Most upvoted comments

@drFabio

Encountering the same issue with sequelize-typescript, everything else is working perfectly but without Sequelize we can’t run the app or @swc-node/jest tests

See if this typeorm sidestep I made is somehow portable to sequelize. Essentially there were infered enum types that did not work and needed to be explicitly set

What solution are you referring to? I do not see anything in this thread. I have the same issues with TypeOrm.

For me it was to explicitly set the types, it seems like there’s a problem inferring the type when built with swc, but if I explicitly set them i.e. decorator @Column({ type: DataTypes.STRING }), then it works without issue.

I’m not sure if TypeORM uses a different format but setting the type explicitly in the decorator solved any Sequelize issues.

mfcodeworks on Jun 15, 2022

I believe this single file limitation will be a deal breaker for most people interested in SWC.

If SWC can’t be a transparent replacement for TSC, there will be just very few use cases where it will be used.

hcesar on Dec 4, 2020

Closing as we are not going to implement project mode of tsc

kdy1 on Jan 23, 2024

Encountering the same issue with sequelize-typescript, everything else is working perfectly but without Sequelize we can’t run the app or @swc-node/jest tests

See if this typeorm sidestep I made is somehow portable to sequelize. Essentially there were infered enum types that did not work and needed to be explicitly set

drFabio on Jun 15, 2022

@Exilz No. I don’t have one.

kdy1 on Feb 22, 2021

@Exilz I’ll fix this soon.

I expect today or tomorrow (It’s almost 11 PM here, so…)

kdy1 on Dec 3, 2020

Encountering the same issue with sequelize-typescript, everything else is working perfectly but without Sequelize we can’t run the app or @swc-node/jest tests

See if this typeorm sidestep I made is somehow portable to sequelize. Essentially there were infered enum types that did not work and needed to be explicitly set

Amazing, this solved all the issues. Somehow tsc infers correct types when building but swc didn’t, but by giving explicit types to Sequelize it works without issue. Thank you!

mfcodeworks on Jun 2, 2022

@kdy1 hello and thanks for the awesome product! It works amazing, but we bumped into the same issue with decorator metadata, while trying to adopt SWC in the company. I see that it’s been moved into Blocked by type checker milestone. Is the type-checking feature has been planned to be implemented in any foreseeable future? Thanks.

kdubrovnyi on May 6, 2022

I think the option is enough for tsc mode (or project mode) vs babel mode.

Eventually, I’ll add the ability to run babel plugins without modification. (See https://github.com/swc-project/swc/pull/1416)

kdy1 on Mar 4, 2021

@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.

kdy1 on Dec 3, 2020