[WIP] Drop build and CI support for GHC < 8.0

[emilypi]

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• Patches conform to the coding conventions.
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[emilypi]

@fgaz do you mind taking a look at the cabal-testsuite here? It looks like the macros aren't expanding.

[emilypi]

This seems to be an uncaught bug.

[Mikolaj]

I think this was caught and fixed in Win32 long ago, but then not fixed here.

[fgaz]

@fgaz do you mind taking a look at the cabal-testsuite here? It looks like the macros aren't expanding.

very odd. did you try calling the output normalizer manually on that string? what does it do?

[emilypi]

@fgaz what's the procedure for that?

[fgaz]

Not sure if there's a better way, but i'd just load cabal-testsuite/src/Test/Cabal/OutputNormalizer.hs in ghci and call normalizeOutput directly. If it works, I'd check what's wrong in the NormalizerEnv that gets passed to it (guess: normalizerKnownPackages)

[fgaz]

Quoting @Mikolaj from another pr, What's the status here? How can we help to move it forward?

[fgaz]

Ping! Will you still work on this @emilypi ?

[andreabedini]

If @emilypi is not working on this anymore, I'm happy to be assigned to this. In #7952 I have already dropped the tests for old GHCs, I need to remember to drop the support in the code.

[Mikolaj]

@andreabedini: yes, please, go ahead!

[andreabedini]

oh boy this is going to be a big rebase :D (rolls up sleaves)

[jneira]

We should close this when #8079 is ready for merge, if @emilypi agrees of course

[andreabedini]

This work has been implemented in #8079, which has been merged. Thanks @emilypi for starting this <3