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

Jani Nikula
2019-10-28T09:24:35Z

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?

>
>> 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.

BR,
Jani.

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

--
Jani Nikula, Intel Open Source Graphics Center