felipeochoa / jest-yarn-link-bug

Reproduction case for jest bug

Reproduction repo for jest + yarn-link issue

Installation

cd parent
yarn

It works without linking

npm run test   # inside ./parent dir

You should see all tests pass:

Test Suites: 1 passed, 1 total Tests: 1 passed, 1 total Snapshots: 0 total Time: 0.767s, estimated 1s

It does not work if you link the child in

cd ../child
yarn link
cd ../parent
yarn link child
npm run test

You should see an import failure for ts-jest:

Cannot find module 'ts-jest' from 'index.js'

1 | exports.fn = function() { return 42; } 2 |

 at Resolver.resolveModule (node_modules/jest-resolve/build/index.js:169:17)
 at Object.<anonymous> (../child/index.js:1:103)

It works if you install ts-jest in the child

cd ../child/
yarn add ts-jest
cd ../parent/
npm run test

You should see all tests pass again:

Test Suites: 1 passed, 1 total Tests: 1 passed, 1 total Snapshots: 0 total Time: 0.655s