GitHub - jamiebuilds/ts-bug (original) (raw)

ts-bug

Trying to compile the same module using --esModuleInterop with bothcommonjs and esnext modules

With the import:

import fn from 'external';

And the library definition:

declare function fn(): void; declare module "external" { export = fn; }

This works:

$ tsc --esModuleInterop --module commonjs

This fails:

$ tsc --esModuleInterop --module esnext

With this error:

error TS1192: Module '"external"' has no default export.

You also cannot use import fn = require('external'):

error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.

Or const fn = require('external'):

error TS2304: Cannot find name 'require'.

But really the first should work because if you specify esModuleInterop and esnext, TypeScript should assume your compiler will take care of it. Otherwise why would you specify that option?