Support expect.addSnapshotSerializer()

[fisker]

Fixes #28

I haven't test, but seems this is how it works. https://github.com/facebook/jest/blob/bb0956589f9dbddcc13db0f42b2d4d9ff642b2cd/packages/jest-expect/src/index.ts#L35

Tested, it works.

[SimenB]

This runner can probably import and use @jest/expect instead of expect directly, fwiw. then you can drop the manual expect.extend call to add the snapshot matchers

[fisker]

Good idea, I'll have a test.

[fisker]

It doesn't work as expected, but maybe because there are multiple version of expect. I'll try again.

[SimenB]

yarn dedupe maybe? not sure what error you got

[fisker]

No error, but expect.addSnapshotSerializer added serializer didn't work. Added to somewhere else?

yarn dedupe

Can't, haven't updated Jest.

[fisker]

Yah, that's the problem. I didn't install @jest/expect for this runner, so I'm using an old version. After I installed a new version of @jest/expect to the runner package, it works.

Can this cause problem? Not sure.

[nicolo-ribaudo]

@jest/expect is just a tiny wrapper around expect (https://unpkg.com/browse/@jest/expect@28.0.2/build/index.js), so it shouldn't cause any problem that we cannot already have with the direct dependency on expect

[nicolo-ribaudo]

I'm assuming the tests will pass on main 😄

[SimenB]

unused

[nicolo-ribaudo]

Thanks! Fixed in 9b0a402