Re: [PATCH v2] kernel-doc: rename the kernel-doc directive 'functions' to 'identifiers'

Changbin Du
2019-10-29T00:31:38Z

On Mon, Oct 28, 2019 at 11:24:22AM +0200, Jani Nikula wrote:
> On Fri, 25 Oct 2019, Changbin Du <changbin.du@gmail.com> wrote:
> > On Fri, Oct 25, 2019 at 09:57:48AM +0300, Jani Nikula wrote:
> >> On Thu, 24 Oct 2019, Jonathan Corbet <corbet@lwn.net> wrote:
> >> > On Sun, 20 Oct 2019 21:17:17 +0800
> >> > Changbin Du <changbin.du@gmail.com> wrote:
> >> >
> >> >> The 'functions' directive is not only for functions, but also works for
> >> >> structs/unions. So the name is misleading. This patch renames it to
> >> >> 'identifiers', which specific the functions/types to be included in
> >> >> documentation. We keep the old name as an alias of the new one before
> >> >> all documentation are updated.
> >> >>
> >> >> Signed-off-by: Changbin Du <changbin.du@gmail.com>
> >> >
> >> > So I think this is basically OK, but I have one more request...
> >> >
> >> > [...]
> >> >
> >> >> diff --git a/Documentation/sphinx/kerneldoc.py b/Documentation/sphinx/kerneldoc.py
> >> >> index 1159405cb920..0689f9c37f1e 100644
> >> >> --- a/Documentation/sphinx/kerneldoc.py
> >> >> +++ b/Documentation/sphinx/kerneldoc.py
> >> >> @@ -59,9 +59,10 @@ class KernelDocDirective(Directive):
> >> >> optional_arguments = 4
> >> >> option_spec = {
> >> >> 'doc': directives.unchanged_required,
> >> >> - 'functions': directives.unchanged,
> >> >> 'export': directives.unchanged,
> >> >> 'internal': directives.unchanged,
> >> >> + 'identifiers': directives.unchanged,
> >> >> + 'functions': directives.unchanged, # alias of 'identifiers'
> >> >> }
> >> >> has_content = False
> >> >>
> >> >> @@ -71,6 +72,7 @@ class KernelDocDirective(Directive):
> >> >>
> >> >> filename = env.config.kerneldoc_srctree + '/' + self.arguments[0]
> >> >> export_file_patterns = []
> >> >> + identifiers = None
> >> >>
> >> >> # Tell sphinx of the dependency
> >> >> env.note_dependency(os.path.abspath(filename))
> >> >> @@ -86,19 +88,22 @@ class KernelDocDirective(Directive):
> >> >> export_file_patterns = str(self.options.get('internal')).split()
> >> >> elif 'doc' in self.options:
> >> >> cmd += ['-function', str(self.options.get('doc'))]
> >> >> + elif 'identifiers' in self.options:
> >> >> + identifiers = self.options.get('identifiers').split()
> >> >> elif 'functions' in self.options:
> >> >> - functions = self.options.get('functions').split()
> >> >> - if functions:
> >> >> - for f in functions:
> >> >> - cmd += ['-function', f]
> >> >> - else:
> >> >> - cmd += ['-no-doc-sections']
> >> >> + identifiers = self.options.get('functions').split()
> >> >
> >> > Rather than do this, can you just change the elif line to read:
> >> >
> >> > elif ('identifiers' in self.options) or ('functions' in self.options):
> >> >
> >> > ...then leave the rest of the code intact? It keeps the logic together,
> >> > and avoids the confusing distinction between identifiers=='' and
> >> > identifiers==None .
> >>
> >> I think the problem is you still need to distinguish between the two for
> >> the get('functions') part.
> >>
> >> One option is to rename 'functions' to 'identifiers' in the above block,
> >> and put something like this above the whole if ladder (untested):
> >>
> >> # backward compat
> >> if 'functions' in self.options:
> >> if 'identifiers' in self.options:
> >> kernellog.warn(env.app, "fail")
> > This will miss the content of 'functions' directive if both exist in
> > same doc.
>
> Did you not notice your patch does the same, except silently, while this
> would produce a warning? Which one is less surprising?
>
yes, my mistake. Mine does the same thing.

> >
> >> else:
> >> self.options.set('identifiers', self.options.get('functions'))
> >>
> >> BR,
> >> Jani.
> >>
> > After comparing, I still perfer my original code which is simpler. :)
>
> But is it, really? I agree with Jon about the distinction between None
> and '' being confusing.
>
Here python is different from C. Both empty string and None are False in python.
Note such condition is common in python.

Again, I am ok with both.

>
> BR,
> Jani.
>
>
>
> >
> >>
> >> --
> >> Jani Nikula, Intel Open Source Graphics Center
>
> --
> Jani Nikula, Intel Open Source Graphics Center

--
Cheers,
Changbin Du