fix(snapshot): bring back support for array property matchers

[bakasmarius]

Summary

Fixes #13352 which is a regression that happened when #13263 fixed #13134.

Technically, this will now throw an error again on the case mentioned in #13134:
expect([{}]).toMatchSnapshot([expect.anything()])

But I don't see a valid use case for this knowing that these cases worked fine before #13263:

expect([{}]).toMatchSnapshot(expect.anything())
expect([{ foo: 'bar' }]).toMatchSnapshot([{ foo: expect.anything() }])

---

Test plan

Tests added

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[mrazauskas]

Technically, this will now throw an error again on the case mentioned in #13134: expect([{}]).toMatchSnapshot([expect.anything()])

Unfortunately the error is hard to understand: "Asymmetric matcher Object does not implement toAsymmetricMatcher()"

But I don't see a valid use case for this knowing that these cases worked fine before #13263:

A user was reporting an error, which was hard to understand. The fix was not about one or another use case.

[bakasmarius]

Technically, this will now throw an error again on the case mentioned in #13134: expect([{}]).toMatchSnapshot([expect.anything()])

Unfortunately the error is hard to understand: "Asymmetric matcher Object does not implement toAsymmetricMatcher()"

But I don't see a valid use case for this knowing that these cases worked fine before #13263:

A user was reporting an error, which was hard to understand. The fix was not about one or another use case.

Does this mean my PR won't be approved unless it also makes the error mentioned in #13134 more clear?
If so, could somebody please add a failing test case to my PR (or just paste it here) so I could implement a fix for it?
I'm not that familiar with Jest's inner details so I wasn't able to successfully write such a case myself.
I also spent half a day today debugging this case from my own project and trying to narrow it down but I think I'm starting to lose my sanity so I'll give it a rest for a while 😄
Hopefully, someone could point me in the right direction so I could move forward with this PR.

[bakasmarius]

I added some changes (test cases included) that fix #13134 - it doesn't throw any error anymore, because expect.anything() and expect.any(type) just work inside an array now.

These cases (and combinations of them) now also work:
expect([{}]).toMatchSnapshot([expect.anything()])
expect([[]]).toMatchSnapshot([expect.anything()])
expect([5]).toMatchSnapshot([expect.anything()])
expect(['some words']).toMatchSnapshot([expect.anything()])
expect([true, false]).toMatchSnapshot([expect.anything(), expect.anything()])

expect([{}]).toMatchSnapshot([expect.any(Object)])
expect([[]]).toMatchSnapshot([expect.any(Array)])
expect([5]).toMatchSnapshot([expect.any(Number)])
expect(['some words']).toMatchSnapshot([expect.any(String)])
expect([true, false]).toMatchSnapshot([expect.any(Boolean), expect.any(Boolean)])

[SimenB]

Technically, this will now throw an error again on the case mentioned in #13134:
expect([{}]).toMatchSnapshot([expect.anything()])

As long as the error is specific, I think that's fine.

EDIT: hah, just noticed your latest comment 😅

[mrazauskas]

Great job!

Looks like this patch makes .toMatchSnapshot() matcher work the same as .toMatchObject() does. I checked out the branch and did some manual testing. Just wanted to compare the behaviour and to try out few edge cases. All went smooth.

One detail – the PR is missing change log entry. It could sound "feat(jest-snapshot): support array inputs to .toMatchSnapshot() matcher" or so.

[SimenB]

thanks!

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[SimenB]

https://github.com/jestjs/jest/releases/tag/v29.6.0