fix(cabal-install): cabal test runs the tests of the targets that have them

[zlonast]

fix: #11858

$ cabal test pkg-with-tests pkg-without-tests
No tests to run for the package pkg-without-tests-0.1.0.0
Running 1 test suites...
Test suite pkg-with-tests-test: PASS
1 of 1 test suites (1 of 1 test cases) passed.

---

Template Α: This PR modifies behaviour or interface

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[chreekat]

I have pointed out a few typical mistakes made by agents of the current era. There are more to be found. I suggest taking a look and trying to improve its output.

[chreekat]

Sorry to rain on your parade with this review. I do appreciate that you tackled the issue I raised! The new test looks fine; if the impl was cleaned up I'm sure this would actually fix my problem.

[zlonast]

@chreekat Thanks for the review; this time I decided to take a closer look. I hope you'll find time for another review :)

[chreekat]

Great, thanks again!

[philderbeast]

The cabal test --help comment on --test-fail-when-no-test-suites is very short. It could be worth explaining this flag's behaviour in more detail in the cabal test section of the user guide.

cabal/doc/cmd-v2-help/test.txt

Lines 349 to 351 in aeb7dbf

	--test-fail-when-no-test-suites
	# Exit with failure when no test suites are
	found.

cabal/doc/cabal-commands.rst

Lines 1340 to 1344 in aeb7dbf

	cabal test
	^^^^^^^^^^
	``cabal test [TARGETS] [FLAGS]`` tests test suites specified as targets
	after ensuring they are up to date and building them, if necessary.

[zlonast]

@philderbeast Thanks, I've left a note.

[philderbeast]

When reviewing, I added some cabal-testsuite package tests that I'd like you to include.

0001-Add-tests-for-running-all-tests-that-exist.patch

I'm not sure what the behaviour should be when the targets are p:tests q:tests instead of p q, so this is a separate patch that for now records the current failing behaviour.

0002-Failures-with-p-tests-and-q-tests.patch

If we do want the behaviour to be the same with :tests filters on the target selectors then I have explored that too.

0003-Behave-the-same-with-tests-targets.patch
0004-Update-the-test-expectations-and-output.patch
0005-Add-assertion-helpers-reorder-tests.patch

[philderbeast]

#12376 has merged so rebasing should enable that failing test to now pass.

[zlonast]

Thanks for the tests, @philderbeast! I think :tests consistent skipping is what users expect.