Make it build with ghc-9.12

[erikd]

Passed all test locally with ghc-9.6, ghc-9.10 and ghc-9.12.

[tchoutri]

Thank you so much!!!

[tchoutri]

@erikd Would you mind updating the tested-with field of the cabal files you have updated?

[erikd]

I don't understand why if failed with ghc-9.12.

The failure:

Run cabal install --ignore-project -j2 doctest --constraint='doctest ^>=0.22'
Resolving dependencies...
Error: [Cabal-7107]
Could not resolve dependencies:
[__0] next goal: doctest (user goal)
[__0] rejecting: doctest; 0.24.0, 0.23.0 (constraint from command line flag requires ^>=0.22)
[__0] trying: doctest-0.22.10
[__1] next goal: ghc (dependency of doctest)
[__1] rejecting: ghc-9.12.1/installed-a75a (conflict: doctest => ghc>=8.0 && <9.12)
[__1] skipping: ghc-9.12.1 (has the same characteristics that caused the previous version to fail: excluded by constraint '>=8.0 && <9.12' from 'doctest')
[__1] rejecting: ghc; 9.10.1, 9.8.2, 9.8.1, 9.6.6, 9.6.5, 9.6.4, 9.6.3, 9.6.1, 9.4.8, 9.4.7, 9.4.6, 9.4.5, 9.4.4, 9.4.3, 9.4.2, 9.4.1, 9.2.8, 9.2.7, 9.2.6, 9.2.5, 9.2.4, 9.2.3, 9.2.2, 9.2.1, 9.0.2, 8.10.7, 8.10.2, 8.10.1, 8.8.3, 8.8.1, 8.6.5, 8.6.4, 8.6.1, 8.4.4, 8.4.3, 8.4.1, 8.2.2, 8.2.1, 9.2.3.20220620 (constraint from non-reinstallable package requires installed instance)
[__1] fail (backjumping, conflict set: doctest, ghc)
After searching the rest of the dependency tree exhaustively, these were the goals I've had most trouble fulfilling: ghc, doctest

Where is --constraint='doctest ^>=0.22 coming from? ALl the cabal files have < 0.25.

Update: Nevermind. Think I have fixed it.

[tchoutri]

Wonderful, thank you @erikd. :)