Re: [PATCH] perf build: Specify that spellcheck should use the bash dialect.

[James Clark]

On 20/06/2025 8:49 pm, Namhyung Kim wrote:
> Hello,
>
> On Thu, Jun 19, 2025 at 11:28:46AM +0100, James Clark wrote:
> > On 13/06/2025 4:36 am, Collin Funk wrote:
> > > When someone has a global shellcheckrc file, for example at
> > > ~/.config/shellcheckrc, with the directive 'shell=sh', building perf
> > > will fail with many shellcheck errors like:
> > >
> > >       In tests/shell/base_probe/test_adding_kernel.sh line 294:
> > >       (( TEST_RESULT += $? ))
> > >       ^---------------------^ SC3006 (warning): In POSIX sh, standalone ((..)) is undefined.
> > >
> > >       For more information:
> > >         https://www.shellcheck.net/wiki/SC3006 -- In POSIX sh, standalone ((..)) is...
> > >       make[5]: *** [tests/Build:91: tests/shell/base_probe/test_adding_kernel.sh.shellcheck_log] Error 1
> > >
> > > Passing the '-s bash' option ensures that it runs correctly regardless
> > > of a developers global configuration.
> > >
> > > Signed-off-by: Collin Funk <collin.funk1@xxxxxxxxx>
> > > ---
> > >    tools/perf/tests/Build | 2 +-
> > >    1 file changed, 1 insertion(+), 1 deletion(-)
> > >
> > > diff --git a/tools/perf/tests/Build b/tools/perf/tests/Build
> > > index 2181f5a92148..26efc5d20f6c 100644
> > > --- a/tools/perf/tests/Build
> > > +++ b/tools/perf/tests/Build
> > > @@ -89,7 +89,7 @@ endif
> > >    $(OUTPUT)%.shellcheck_log: %
> > >    	$(call rule_mkdir)
> > > -	$(Q)$(call echo-cmd,test)shellcheck -a -S warning "$<" > $@ || (cat $@ && rm $@ && false)
> > > +	$(Q)$(call echo-cmd,test)shellcheck -s bash -a -S warning "$<" > $@ || (cat $@ && rm $@ && false)
> > >    perf-test-y += $(SHELL_TEST_LOGS)
> >
> > If we're enforcing bash style with static analysis shouldn't we also change
> > all the hashbangs to bash? Recently there have been changes to change sh to
> > bash in some of the tests so presumably the hard rule for sh is no more?
> >
> > In the past I've had to replace bashisms that didn't work in sh but it would
> > be nice to have only one language to write tests in. I doubt anyone running
> > the tests today is running somewhere without bash, or that changing it will
> > break anything. If anything it will fix more bashisms that have already been
> > written.
> >
> > Just for reference there are 34 #!/bin/bash and 42 #!/bin/sh in
> > tools/perf/tests
>
> Thanks for raising the concern.  I agree that having one standard is a
> way to go but I really don't have preference between those shells.
>
> Thanks,
> Namhyung

I would vote for bash then, just because it has a few extra builtins 
that are sometimes useful. I can send a patch that does the change to 
see if anyone objects.

Thanks
James