How to use Jest and Electron?

[NodeGuy]

Issue description or question

When I try to run my Jest tests in Electron I see the following error message:

​​[Error] Failed to load configuration file:  Test framework [jest] is not supported​​
​​​​​[Info]​​​​​ Started Wallaby.js Core v1.0.568

Wallaby.js configuration file

module.exports = wallaby => {
  return {
    files: ["build/lib/**/*.js"],
    tests: ["build/test/**/*.js"],
    env: {
      kind: 'electron'
    },
    testFramework: "jest",
  };
};

Code editor or IDE name and version

Visual Studio Code v1.21.1

OS name and version

macOS 10.13.3

[ArtemGovorov]

Jest runs in node, not sure if it can run in Electron - I haven't seen anyone using Jest with Electron (even without wallaby). Even if plain Jest works with Electron, we will need to add the support separately.

[NodeGuy]

We're using Jest with Electron: https://github.com/cosmos/voyager

I look forward to you adding support.

[ArtemGovorov]

@NodeGuy Thanks for the repo link!

[ArtemGovorov]

Correct me me if I'm wrong, but I can't see where you are running Jest with Electron, from what I can see, your package.json is running Jest tests in node:

"test:unit": "cross-env LOGGING=false MOCK=false ANALYTICS=false NODE_ENV=testing jest --maxWorkers=2",

To do the same in wallaby you may use

env: {
  type: 'node'
}

instead of

env: {
  kind: 'electron'
},

[NodeGuy]

Oh dear, how embarrassing. I'm new to the project and to Jest and made an incorrect assumption; thanks for pointing it out.

[marcelh-gh]

@ArtemGovorov according to the Wallaby Jest is not supported to run in Node. Here it sounds, it is supported. What is the current status? Thanks!

[ArtemGovorov]

Jest is not supported to run in Node

Jest is supported to run in Node in Wallaby. You may find the sample config in our docs.

[marcelh-gh]

@ArtemGovorov Thanks. You might want to update the info in https://wallabyjs.com/docs/integration/overview.html Under Supported testing frameworks Jest is only listed under "for browser" and not under "for Node"

[ArtemGovorov]

@marcelh-gh Thanks for the note. The docs had been updated.

[TreTuna]

There is an option in Electron to run as a normal Node process by setting the ENV variable ELECTRON_RUN_AS_NODE=true. This is how we're using Jest with Electron. The command that we use to run our tests is ELECTRON_RUN_AS_NODE=true ./node_modules/.bin/electron ./node_modules/.bin/jest Perhaps this could be leveraged to run Wallaby on Electron apps with Jest? https://electronjs.org/docs/api/environment-variables#electron_run_as_node

[ArtemGovorov]

@TreTuna I haven't tried, but if Electron starts as node with the flag, then maybe this could work:

module.exports = function () {
  return {
    ...

    env: {
      type: 'node',
      runner: require('electron'), // this should return electron binary path
      params: {
        env: 'ELECTRON_RUN_AS_NODE=true'
      }
    }
  };
};

[TreTuna]

@ArtemGovorov Well, that seems to work! I don't have any tests written in this repo yet that involve Electron processes, but it's running the very basic ones I have going on this. However, it does load up 6 Electron processes in the process. Which seems a bit excessive.

[ArtemGovorov]

@TreTuna Awesome, thanks for the update.

However, it does load up 6 Electron processes in the process. Which seems a bit excessive.

Wallaby runs tests in parallel using multiple worker processes. You may control the number of workers with the workers setting.

[NetizenAbel]

Jest runs in node, not sure if it can run in Electron - I haven't seen anyone using Jest with Electron (even without wallaby). Even if plain Jest works with Electron, we will need to add the support separately.

I'm using jest with electron.

[smcenlly]

@kashaiahyah85 - were you able to get this working with @ArtemGovorov's previous suggested fix mentioned in this issue?

[NetizenAbel]

Actually, @smcenlly , I'm just using facebook-atom/jest-electron-runner more or less according to its documentation, and selectively mocking things when necessary. You'll need two different jest configurations (projects), one for main and one for the renderer. I go the route of trying the tests all in main, then separating what I need to, because the main process is a little faster on average for testing.

This is how I've configured that.

[samdesota]

Hey, I also use jest with electron, facebook-atom/jest-electron-runner works quite well, but I haven't been able to get wallaby to work with this, it would be very useful if this was supported.