[testing] register chai plugins type error

Hi!

Since the last minor version 2.3.0, where there is an update of using chai plugins, it throws an error whenever you try to execute the tests with npm run test command.

This is the error I mention:

TypeError: Cannot read property 'use' of undefined at Module../node_modules/@open-wc/testing/register-chai-plugins.js (http://localhost:9876/absoluteC:/Users/AppData/Local/Temp/_karma_webpack_/commons.js?75a6c001bc3dabe4571a9762f775846886fba511:27698:13) at __webpack_require__ (http://localhost:9876/absoluteC:/Users/AppData/Local/Temp/_karma_webpack_/runtime.js?c38d51cd4af62e9eacd04bb5dfbfbac27880397b:85:30) at Module../node_modules/@open-wc/testing/index.js

I do not know if there is any config missing I have to include due to this update, but it is failing when it tries to use those plugins as window.chai seems not to be registered well.

This is the line I mention in register-chai-plugins.js file: window.chai.use(chaiDomDiff);

Thanks in advance!!

[daKmoR]

if you are using karma-webpack you can try to add chai/chai.js to your files in the karma.conf.js

files: [
  { pattern: require.resolve('chai/chai.js' }, 
  // other files
]

if that solves your problem would you be willing to add this information to our documentation via a PR? 🤗

[stale[bot]]

Hey there, it’s me again! I am going close this issue to help our maintainers focus on the current development roadmap instead. If the issue mentioned is still a concern, please open a new ticket and mention this old one. Cheers and thanks for using Open Web Components!