Support for jest 27

[ankrut]

In Jest 27 the helper jest.addMatchers has been removed. Instead it is recommended to use expect.extend which is not compatible with jest-jquery-matchers. As far as I understand comperator can be simply removed to get proper matchers.

[unindented]

I don't currently use this library, but I'm open to PRs. Feel free to submit @ankrut!

I feel it should be similar to unindented/custom-immutable-matchers#44

[ankrut]

Yes, the PR would be very similar to unindented/custom-immutable-matchers#44. Unfortunately, I am not able to run the project, i.e. npm install fails and so far no luck to fix it.

Therefore, I can provide a blind PR, and maybe you can try your luck assuming you know best how run it.

However, my workaround is to extract the compare functions. For example in a jest.setup.js file.

import * as matchers from 'jest-jquery-matchers'

const jqueryMatchers = {}

for (let key in matchers) {
    jqueryMatchers[key] = matchers[key]().compare
}

expect.extend(jqueryMatchers)

[unindented]

Up to you. You can submit a PR, and if it looks good and it passes all the checks I'll merge it. Or you can do your workaround.