react-scripts@3.0.0 test command hangs

Is this a bug report?

Yes

Did you try recovering your dependencies?

Yes

Which terms did you search for in User Guide?

(Write your answer here if relevant.)

Environment

Environment Info:

  System:
    OS: Windows 10
    CPU: (8) x64 Intel(R) Core(TM) i7-6820HQ CPU @ 2.70GHz
  Binaries:
    Node: 11.1.0 - C:\Program Files\nodejs\node.EXE
    Yarn: 1.15.2 - ~\AppData\Roaming\npm\yarn.CMD
    npm: 6.9.0 - C:\Program Files\nodejs\npm.CMD
  Browsers:
    Edge: 42.17134.1.0
    Internet Explorer: 11.0.17134.1
  npmPackages:
    react: ^16.8.5 => 16.8.6
    react-dom: ^16.8.5 => 16.8.6
    react-scripts: ^2.1.5 => 2.1.8
  npmGlobalPackages:
    create-react-app: Not Found

Also

Same happening on Ubuntu (unable to tell exact version)

Steps to Reproduce

1. npx create-react-app test
2. cd test
3. yarn test

Expected Behavior

Since I don’t have any non staged changes jest should resolve (and run) all the tests.

Actual Behavior

outputs:

$ yarn test
yarn run v1.15.2
$ react-scripts test
No tests found related to files changed since last commit.

and the process hangs (doesn’t exits)

on our Jenkins it ran more than an hour

Reproducible Demo

https://github.com/Teneff/react-scripts-bug

[Teneff]

Hi,

does your test environment have the CI environment variable set to true?

It did not.

Adding it resolved the problem.

"scripts": {
-    "test": "react-scripts test",
+    "test": "cross-env CI=true react-scripts test",
},

But this happened when I’ve upgraded from 2.1.5 to 3.0.0. If react-scripts is not responsible for setting it anymore this should be mentioned in the documentation/changelog.

[Teneff]

The main change I can think of in 3.0 is --coverage used to turn off watch mode, but now that jest supports coverage in watch mode that’s no longer the case.

We’ve always recommend to have the CI env variable set in your CI server if not already set as described at https://facebook.github.io/create-react-app/docs/advanced-configuration. A number of CI providers will set this for you automatically.

as Steps to Reproduce suggest

npx create-react-app test
cd test
yarn test

this issue is also affecting the newly created applications in development environment