Avoid T.must.

[reitermarkus]

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[dduugg]

I think I don't feel strongly either way, my general sense of readability is:

nil forwarding > T.must > assignment in conditionals

but this feels a bit like a wash to me overall

[apainintheneck]

This looks good. Does this pattern show up anywhere else in the codebase? We could probably just replace those usages with this one if more exist.

Also, how militant should we be about removing these extra runtime Sorbet type assertions in general?

[reitermarkus]

I just stumbled over these while refactoring some other alias-related code, so it made sense to also refactor this, but I don't think we need to proactively do anything about this pattern and assertions in general. Of course feel free to take a look, I'd assume this pattern is used in a couple of other places.

[MikeMcQuaid]

Do we expect tap to ever be not nil but formula_oldnames is nil?

If not, the existing code but just without the T.must feels nicer to me than repeatedly chaining &