Re: [PATCH 2/6] qapi/parser: Allow empty QAPIDoc Sections

[Markus Armbruster]

John Snow <jsnow@redhat.com> writes:

> On 5/20/21 10:42 AM, Markus Armbruster wrote:
>> First step is to find out how _end_section() can be called twice in a
>> row.  It isn't in all of "make check".  Hmm.
>
> Ah, maybe not twice in a *row*. It does seem to be called when we have
> an "empty section" sometimes, which arises from stuff like this:
>
> Extension error:
> /home/jsnow/src/qemu/docs/../qga/qapi-schema.json:1143:1: ending a
> totally empty section
>
> ## 
> # @GuestExec: 
> # @pid: pid of child process in guest OS 
> # 
> # Since: 2.5 
> ## 
> { 'struct': 'GuestExec',
>   'data': { 'pid': 'int'} }
>
> Without the newline there, it seems to get confused. There's a few
> like this that could be fixed, but then some of the test cases break
> too.

I still can't see it.  I tried the obvious

    diff --git a/scripts/qapi/parser.py b/scripts/qapi/parser.py
    index f03ba2cfec..263aeb5fc5 100644
    --- a/scripts/qapi/parser.py
    +++ b/scripts/qapi/parser.py
    @@ -716,6 +716,7 @@ def _start_section(self, name=None, indent=0):
             self.sections.append(self._section)

         def _end_section(self):
    +        assert self._section
             if self._section:
                 text = self._section.text = self._section.text.strip()
                 if self._section.name and (not text or text.isspace()):

Does not fire for qga/qapi-schema.json.  Can you help?

> No appetite for barking up this tree right now.
>
> Can I fix the commit message and leave the patch in place? Maybe with
> a #FIXME comment nearby?

I'd like to understand your analysis before I answer your question.