Is it possible to have a check mode, that tells you whether a given GHC version is in the get-tested stanza of a Cabal file or not?
What I mean is something like this:

$ get-tested get-tested.cabal
["9.10.1"]
$ get-tested check get-tested.cabal 9.10.1; echo $?
0
$ get-tested check get-tested.cabal 9.8.2; echo $?
1
$ get-tested check get-tested.cabal 9.8.2 9.10.1; echo $?
1

I know I can work around that (e.g. get-tested get-tested.cabal | jq --raw-output '.[]' | grep -q '9.10.1'), but that's rather hacky...