Demo for ts-jest #805

See kulshekhar/ts-jest#805

How to use

To reproduce the error

yarn install --frozen-lockfile
cd packages/my-app/
yarn test --no-cache

Output:

$ yarn test --no-cache
yarn run v1.21.1
$ jest --no-cache
 FAIL   my-app  ./main.test.ts
  ● Test suite failed to run

    TypeError: Unable to require `.d.ts` file.
    This is usually the result of a faulty configuration or import. Make sure there is a `.js`, `.json` or another executable extension available alongside `index.ts`.

      at getOutput (../../node_modules/ts-jest/dist/compiler.js:165:23)

Test Suites: 1 failed, 1 total
Tests:       0 total
Snapshots:   0 total
Time:        2.111s
Ran all test suites.
error Command failed with exit code 1.
info Visit

The error can also be reproduced by running all the test projects from the root directory.

To work around the error

isolatedModules

Set isolatedModules to true in packages/my-app/jest.config.js.

preserveSymlinks

Set preserveSymlinks to true in packages/my-app/tsconfig.json.