Make VALID and INVALID covariant
#541
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By using `Sequence`, these become covariant. Previously, doing something like:
```
VALID = [
ValidTestCase("..."),
ValidTestCase("..."),
]
```
would be a type error in `pyre`, because `pyre` would infer this to be a `list[ValidTestCase]` which is *not* a subclass of `list[str | ValidTestCase]`. By making these `Sequence`s (and thus immutable), we can avoid the requirement of having explicit type annotations everywhere for this.
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Summary
By using
Sequence, these become covariant. Previously, doing something like:would be a type error in
pyre, becausepyrewould infer this to be alist[ValidTestCase]which is not a subclass oflist[str | ValidTestCase]. By making theseSequences (and thus immutable), we can avoid the requirement of having explicit type annotations everywhere for this.Test Plan