ES6 module import doesn't require relative identifier to load relative file #4214
Description
This could be by design but it just surprised me and I wanted to verify behavior.
With CommonJS, relative modules must start with "./" or "../", otherwise it's considered to be a top-level module.
As near as I can tell with ES6, module naming is "loader implementation specific". It would seem that TypeScript's implementation does not require "./" or "../" to reference a relative file. For example:
// dep.ts
export class Test {}
// app.ts
import { Test } from 'dep';Is this intended? I'm not super familiar with prevailing ES6 module loading standards, but I put together a quick test using SystemJS. It also does not allow referencing a relative module without './' or '../' unless that module happens to be in the preconfigured "base" URL. In other words, the above example would probably work out of the box, but the following would not:
// components/helper.ts
export function someHelper();
// components/dep.ts
import * as helper from 'helper'; // this line would error at runtime in SystemJS, but not in TS
export class Test {}
// app.ts
import { Test } from 'components/dep';My understanding is that work is being made in #2338 and things like #4154 which may help to alleviate issues like this since it would allow TypeScript to be aware of that "loader-implementation specific" part. In the meantime, is the current default correct? As an alternative, perhaps it would make sense for ES6 imports to not have this behavior if --module commonjs is set, since this clearly does not follow the CJS spec.