make cabal-install integration tests hermetic

[geekosaur]

They were using the user's config, which is a problem if they don't have one or if it contains settings that interfere with tests (such as documentation: True).

I'm not entirely certain of this, but it seems to work here. It's a bit of a hack, though.

Closes: #10187

Template B: This PR does not modify behaviour or interface

E.g. the PR only touches documentation or tests, does refactorings, etc.

Include the following checklist in your PR:

• Patches conform to the coding conventions.
• Is this a PR that fixes CI? If so, it will need to be backported to older cabal release branches (ask maintainers for directions).

[geekosaur]

Also, someone told me "nobody runs validate locally" — but I've needed to do so several times, and in particular I prefer to validate locally before bogging down CI when possible.

[geekosaur]

Uh, weird validate error? I don't think that's me, it looks like it hadn't even reached IntegrationTests2 yet.

[geekosaur]

I came up with a change that makes it work locally, but may make some tests unhappy. Guess we'll see. (ETA: seems to be working.)

I could argue the first version was more correct, since we should really not rely on $HOME in any way; it's not so different from why we relocate tests to /tmp now.

[geekosaur]

Manual QA is simple: run validate.sh locally, make sure IntegrationTests2 doesn't fail. This is especially needed for non-Linux platforms.

$ cabal build all
$ ./validate.sh --cli --with-cabal $(cabal list-bin cabal)

(I'm not sure if --cli is needed there.)

[ulysses4ever]

If it "needs-review", it should be un-drafted, presumably...

[geekosaur]

If it "needs-review", it should be un-drafted, presumably...

I would like people to comment on it, specifically on my approach, before I commit to it.

[tbidne]

Nice idea.

I have noticed when running tests locally:

cabal run cabal-testsuite:cabal-tests -- --hide-successes --with-cabal=./bin/cabal

That I receive many failures due to the following lines in the output:

+Warning: Both <ROOT>/cabal.dist/home/.cabal and /home/tommy/.config/cabal/config exist - ignoring the former.
+It is advisable to remove one of them. In that case, we will use the remaining one by default (unless '$CABAL_DIR' is explicitly set).

While the right answer in this particular situation is to delete the extra dir (it appears to be created by nix in some circumstances), it would be nice if the tests were isolated.

My issue may be out of scope for this particular PR (I tried it out and still received the errors), but I thought I'd comment since it seems related.

[geekosaur]

I don't use Nix, so I don't think that's the cause. In any case, this patch sets CABAL_DIR to a newly created configuration tree, which suppresses the extra output per the error message while ensuring that a pristine configuration is used.

[geekosaur]

Also, my guess is you're getting them from things other than the cabal-install integration tests. That's certainly beyond the scope of this particular PR, but is probably worth reporting on its own as an indication that we have other cases of leaky configs.

[ulysses4ever]

Thanks again!

[jasagredo]

Looks reasonable.

I was bitten by this with my:

ghc-options: -optc-Wno-pragma-pack -optc-Wno-macro-redefined -optc-Wno-missing-declarations

for this: https://gitlab.haskell.org/ghc/ghc/-/issues/25031

[geekosaur]

@mergify backport 3.12

[mergify]

backport 3.12

✅ Backports have been created

• #10218 make cabal-install integration tests hermetic (backport #10205) has been created for branch 3.12