Support for TypeScript 3.7.2

Hello!

ts-jest currently does not work with TypeScript 3.7.2. Import statements are not transformed in the transformed code of imports in test files.

src/db/seeds/1-users/users.ts:1
import { ObjectId } from '../../../app/helpers/db';
       ^

SyntaxError: Unexpected token {
    at Module._compile (internal/modules/cjs/loader.js:703:23)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:770:10)
    at Module.load (internal/modules/cjs/loader.js:628:32)
    at Function.Module._load (internal/modules/cjs/loader.js:555:12)
    at Module.require (internal/modules/cjs/loader.js:666:19)
    at require (internal/modules/cjs/helpers.js:16:16)

[ChrisLahaye]

For me the problem was that I was using target: esnext which tells the compiler that your runtime will be able to handle esnext features, i.e. supports the nullish coalescing and optional chaining operator. I am using node 12 which only supports up until es2018. For people encountering this problem, check what runtime you are using and which features (e.g. operators and functions) are supported (see https://node.green/), and then set your target appropriately.

[squalsoft]

Yes, “target”: “ES2019” resolves this issue!