Re: [PATCH v2] clang-tools: Print information when clang-tidy tool is missing

From: Nathan Chancellor
Date: Sun Aug 08 2021 - 18:18:17 EST


On Sat, Aug 07, 2021 at 01:01:16PM +0200, Maciej Falkowski wrote:
> When clang-tidy tool is missing in the system, the FileNotFoundError
> exception is raised in the program reporting a stack trace to the user:
>
> $ ./scripts/clang-tools/run-clang-tools.py clang-tidy ./compile_commands.json
> multiprocessing.pool.RemoteTraceback:
> """
> Traceback (most recent call last):
> File "/usr/lib64/python3.8/multiprocessing/pool.py", line 125, in worker
> result = (True, func(*args, **kwds))
> File "/usr/lib64/python3.8/multiprocessing/pool.py", line 48, in mapstar
> return list(map(*args))
> File "./scripts/clang-tools/run-clang-tools.py", line 54, in run_analysis
> p = subprocess.run(["clang-tidy", "-p", args.path, checks, entry["file"]],
> File "/usr/lib64/python3.8/subprocess.py", line 489, in run
> with Popen(*popenargs, **kwargs) as process:
> File "/usr/lib64/python3.8/subprocess.py", line 854, in __init__
> self._execute_child(args, executable, preexec_fn, close_fds,
> File "/usr/lib64/python3.8/subprocess.py", line 1702, in _execute_child
> raise child_exception_type(errno_num, err_msg, err_filename)
> FileNotFoundError: [Errno 2] No such file or directory: 'clang-tidy'
> """
>
> The patch adds more user-friendly information about missing tool:
>
> $ ./scripts/clang-tools/run-clang-tools.py clang-tidy ./compile_commands.json
> Command 'clang-tidy' is missing in the system
>
> Signed-off-by: Maciej Falkowski <maciej.falkowski9@xxxxxxxxx>
> Link: https://github.com/ClangBuiltLinux/linux/issues/1342

LGTM, I think this is much better than the stacktrace output as above as
it is easier for someone who is not familiar with these scrips to act
on.

Reviewed-by: Nathan Chancellor <nathan@xxxxxxxxxx>

> ---
> Hi Masahiro,
>
> Thank you for your feedback!
> I am sorry that I haven't replied for so long.
>
> I agree with your point, based on this I would like
> to propose a second version of the patch.
>
> changes in v2:
> - Solution has changed from LBYL style to EAFP
>
> Best regards,
> Maciej Falkowski
> ---
> scripts/clang-tools/run-clang-tools.py | 9 ++++++++-
> 1 file changed, 8 insertions(+), 1 deletion(-)
>
> diff --git a/scripts/clang-tools/run-clang-tools.py b/scripts/clang-tools/run-clang-tools.py
> index fa7655c7cec0..27ebe2f2069a 100755
> --- a/scripts/clang-tools/run-clang-tools.py
> +++ b/scripts/clang-tools/run-clang-tools.py
> @@ -67,7 +67,14 @@ def main():
> # Read JSON data into the datastore variable
> with open(args.path, "r") as f:
> datastore = json.load(f)
> - pool.map(run_analysis, datastore)
> + try:
> + pool.map(run_analysis, datastore)
> + except FileNotFoundError as err:
> + if err.filename == 'clang-tidy':
> + print("Command 'clang-tidy' is missing in the system", file=sys.stderr)
> + sys.exit(127)
> + else:
> + raise err
>
>
> if __name__ == "__main__":
> --
> 2.26.3