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Redefine type always emit Object design:type

See original GitHub issue


I have an issue, when I define a type like this: export type Uuid = string;

The emit type is: Object

The full case:

export type Uuid = string;

function Decorate() {
    return (target: any, prop: string): any => {
        const propertyType = Reflect.getMetadata("design:type", target, prop);
        console.log('propertyType', propertyType); // emit the Object type

class Foo {
    public bar!: Uuid;

and my babel config:

// babel.config.js
module.exports = {
    presets: [
        ["@babel/preset-env", { "targets": { "node": "current" }, "modules": "commonjs" }],
    "plugins": [
        ["@babel/plugin-proposal-decorators", { "legacy": true }],
        ["@babel/proposal-class-properties", { "loose": true }],

I don’t know if it’s a defect coming from my Babel configuration, or a limitation from @babel/preset-typescript.

Issue Analytics

  • State:open
  • Created 3 years ago
  • Comments:5 (3 by maintainers)

github_iconTop GitHub Comments

leonardfactorycommented, May 28, 2020

I’ve used it exactly with the same setup, but not in production, where we reverted to TypeScript only (no babel, but same toolkit). With TypeORM you should be careful to use @Column(), even if for plain cases it still works and for advanced cases you still need to declare it manually anyway. With NestJS it works properly but TS support is still better.

namnmcommented, May 28, 2020

@leonardfactory Thanks for the suggestion and quick reply. Just one more thing, I came here from the issue in the nestjs repo. I see that in the README this package can work well with Nest and TypeORM. Have you had any experiment project using this package for Nest? Is there any cautions that I need to take if I use this package in production with Nest and TypeORM?

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