Running tests using Jest framework

If you’re using the Jest testing framework, Sealights-jest-plugin can be directly integrated into your project.

Sealights-jest-plugin is a standalone plugin for use with slnodejs, it’s not meant to replace it.

 Instructions

Running tests:

1. Install

   npm install sealights-jest-plugin

2. In the jest.config.js import configCreator and wrap jest config object in it:

   const {configCreator} = require('sealights-jest-plugin') module.exports = configCreator({ //... jest configuration });

3. From the command line run jest and add sealights parameters with --sl- prefix

   jest __tests__ --sl-testStage='test stage name' --sl-tokenfile=sltoken.txt --sl-buildsessionidfile=buildSessionId

Supported parameters

• sl-token - Sealights token

• sl-tokenFile - Path to file contains the Sealights token

• sl-buildSessionId - Sealights build session id

• sl-buildSessionIdFile - Path to file contains the Sealights build session id

• sl-testStage - Test stage current tests are relates to

• sl-labId - Pre-defined Sealights lab-id (optional)

• sl-proxy - Proxy server (optional)

Create-react-app setup

In order to make sealights-jest-plugin work with create-react-app project you need to set it up correctly, so it produces high quality sourcemaps needed for sealights to work.

To set CRA project do the following:

• Eject the project

• Extract jest configuration from package.json into a separate jest config file called jest.config.js

• Wrap the config in sealights:

in config/webpack.config.js change

after project is setup add following params to the test script:

Note

If you notice that watch mode does not collect the coverage disable it:

Typescipt usage

If your project uses typescript, only thing you need to do is add this to your tsconfig.json

Older versions of jest

You can use sealights plugin with older versions of jest, but first you should install corresponding versions of dependency packages, which are official jest packages. For example to use jest v26 install the following.

If you are using jsdom environment instead of node switch jest-environment-node with jest-environment-jsdom.

Note: Create-react-app uses jsdom

After all the dependencies are installed you can wrap jest config in sealights wrapper and pass the version as parameter

Note: that you don't have to pass version number if you are using jest v27.

Note: if you are not sure which jest version you are using because you are using react-scripts, you can check it's version in package.json after ejecting the project.

Hooks dependency guard

In testing frameworks there are specific cases where the incorrectly set variables in hooks might NOT fail the tests when there is at least one passing test. When the sealights skips this test it will start failing, to avoid that there is a hook dependency guard that detects this case and injects a dummy test to avoid failure.

If it is not a desired behaviour you can disable it by passing the following parameter to sealights

Notes

Currently, the plugin does not support jest-workers, if you are using newer versions of jest that use multiple workers (v27, v26) plugin will configure jest to not use jest-workers.

Plugin depends on the usage of jest-circus test runner, which is the default one in the latest version of Jest. If you are using different type of test runner, the plugin won't be able to collect the test data and coverage.

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