tests: added extra parens compile test

[0xllx0]

Adds a test to verify extra parentheses are discarded, and the source is compiled as expected.

Resolves: #2886, #4148

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[CohenArthur]

Thanks for the contribution @0xllx0! Your test is correct but unfortunately gccrs parses it as a trait and does the wrong thing, and errors out 😬 could you create an issue for this? You can also work on fixing it within this PR if you want

[0xllx0]

gccrs parses it as a trait and does the wrong thing, and errors out 😬 could you create an issue for this? You can also work on fixing it within this PR if you want

How do I get the test to fail then? That's what I was expecting, but marking it as a "should fail" test didn't feel right, as the test is expected to eventually pass, but should fail now.

I opened a tracking issue for the test mismatch: #4148

I'd be happy to work on the fix in this PR.

[0xllx0]

Your test is correct but unfortunately gccrs parses it as a trait and does the wrong thing, and errors out 😬 could you create an issue for this? You can also work on fixing it within this PR if you want

I think I figured out the problem, just needed to add dg-warning directive comments. The parens test now fails as expected, and includes checks for the expected warning messages (can be adjusted based on the actual warnings output by gccrs after a parsing fix).

[powerboat9]

If gccrs is behaving incorrectly, I'd think it'd be proper to add a test verifying gccrs behaves ~correctly after/while making sure that gccrs behaves correctly.

[0xllx0]

If gccrs is behaving incorrectly, I'd think it'd be proper to add a test verifying gccrs behaves ~correctly after/while making sure that gccrs behaves correctly.

Alright, so while the ICE exists, mark this test as xfail, and change the test to check for expected warnings once the fix is in?

[CohenArthur]

That looks good, thank you!