fromJust being called on Nothing

[isovector]

While working on getting Wingman ported to GHC 9, some of my tests are failing with:

tests: Maybe.fromJust: Nothing
CallStack (from HasCallStack):
  error, called at libraries/base/Data/Maybe.hs:148:21 in base:Data.Maybe
  fromJust, called at src/Language/LSP/Test.hs:335:20 in lsp-test-0.14.0.2-29re4UM6EdpFi5JGbWhWu:Language.LSP.Test

I don't have a repro, but the fact that this can happen at all is a good argument against using fromJust.