Add tests for autogen-modules as main-is

[philderbeast]

A question came up in #11390.

Is it that autogen-modules can't be used with a custom main-is, or that the module in main-is can't be an autogenerated module.

These tests show, for executables, test suites and benchmarks, that autogenerated modules can be set as the main-is module and cabal act-as-setup configure will pass but cabal act-as-setup sdist will fail because it can't find the main module.

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[philderbeast]

So far these tests only use setup' that uses cabal act-as-setup. We could also try a cabal build with these packages:

$ cabal build MainIsExe --project-dir=.
Warning: this is a debug build of cabal-install with assertions enabled.
Resolving dependencies...
Build profile: -w ghc-9.12.2 -O1
In order, the following will be built (use -v for more details):
 - MainIsExe-0.1 (exe:Exe) (first run)
Warning: this is a debug build of cabal-install with assertions enabled.
Configuring executable 'Exe' for MainIsExe-0.1...
Warning: this is a debug build of cabal-install with assertions enabled.
Preprocessing executable 'Exe' for MainIsExe-0.1...
Error: [Cabal-7554]
can't find source for MyDummy in
  .
, dist-newstyle/build/x86_64-linux/ghc-9.12.2/MainIsExe-0.1/x/Exe/build/Exe/autogen
, dist-newstyle/build/x86_64-linux/ghc-9.12.2/MainIsExe-0.1/x/Exe/build/global-autogen
Error: [Cabal-7125]
Failed to build exe:Exe from MainIsExe-0.1.

[Mikolaj]

Yay, more (good!) tests. Thank you.

We could also try a cabal build with these packages

Yes, let's do!

[philderbeast]

I've added the cabal build tests. The executable test fails with a different message to the test suite and benchmark tests that both fail with MyDummy.hs doesn't exist.

- MyDummy.hs doesn't exist
+ can't find source for MyDummy in ., cabal.dist/work/./dist/build/<ARCH>/ghc-<GHCVER>/MainIsExe-0.1/x/Exe/build/Exe/autogen, cabal.dist/work/./dist/build/<ARCH>/ghc-<GHCVER>/MainIsExe-0.1/x/Exe/build/global-autogen

[mergify]

Merge Queue Status

✅ The pull request has been merged at 11686ad

This pull request spent 10 minutes 49 seconds in the queue, with no time running CI.
The checks were run in-place.

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  • Add tests for autogen-modules as main-is #11457
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