Include an ability to write the actual snapshot to disk (with a debug flag) when there is a snapshot mismatch

Clear and concise description of the problem

So when a snapshot is mismatched the only place where the comparison is presented is in the test output.

And then a rerun is required in order to update the snapshot.

And when there are lot of snapshot tests that have mismatches this can be quite tedious.

Suggested solution

Please include an ability that when there is a mismatch to write the actual snapshot to disk as a file with some suitable debug flag included.

That way devs can compare the actual with expected and conclude whether the difference is significant and then easily update the expected with changes from the new actual.

This tool from java context has this facility and it is very convenient and I miss it with vitest.

Alternative

No response

Additional context

No response

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