gh-98894: Check readelf failures in test_dtrace

[stratakis]

Report readelf command failures directly instead of later failing with missing-probe assertions.

• Issue: Some DTrace probes are broken in 3.11 #98894

[stratakis]

cc @vstinner

[vstinner]

get_readelf_version() and get_readelf_output() share most code to spawn the subprocess. Can you move the common code into a run_readelf(command) function?

Something like:

def run_readelf(cmd):
    # Force the C locale to disable localization.
    env = dict(os.environ, LC_ALL="C")
    proc = subprocess.Popen(
        cmd,
        stdout=subprocess.PIPE,
        stderr=subprocess.PIPE,
        universal_newlines=True,
        env=env,
    )
    with proc:
        stdout, stderr = proc.communicate()

    if proc.returncode:
        raise AssertionError(
            f"Command {' '.join(cmd)!r} failed "
            f"with exit code {proc.returncode}: "
            f"stdout={version!r} stderr={stderr!r}"
        )

    return stdout

You can replace legacy universal_newlines=True with text=True :-)

[miss-islington-app]

Thanks @stratakis for the PR, and @vstinner for merging it 🌮🎉.. I'm working now to backport this PR to: 3.13, 3.14, 3.15.
🐍🍒⛏🤖

[miss-islington-app]

Sorry, @stratakis and @vstinner, I could not cleanly backport this to 3.14 due to a conflict.
Please backport using cherry_picker on command line.

cherry_picker d60a6779e8dd5fbf1f2f84b34bb5a20f3e8cd7fd 3.14

[miss-islington-app]

Sorry, @stratakis and @vstinner, I could not cleanly backport this to 3.13 due to a conflict.
Please backport using cherry_picker on command line.

cherry_picker d60a6779e8dd5fbf1f2f84b34bb5a20f3e8cd7fd 3.13

[bedevere-app]

GH-152891 is a backport of this pull request to the 3.15 branch.

[stratakis]

3.14 and 3.13 are not relevant here due to the dtrace support not being there in a proper way (it will to be backported fully from #142397 )

[vstinner]

Merged, thanks for your fix.

3.14 and 3.13 are not relevant here due to the dtrace support not being there in a proper way (it will to be backported fully from #142397 )

Oh ok. No 3.13 and 3.14 backport in this case.