Re: [PATCH v4 3/4] meson: Move the detection logic for sphinx to meson

[Paolo Bonzini <pbonzini@redhat.com>]

On 16/10/20 09:52, 罗勇刚(Yonggang Luo) wrote:
> 
>> build_docs = false
>> if sphinx_build.found()
>>   # This is a bit awkward but works: create a trivial document and
>>   # try to run it with our configuration file (which enforces a
>>   # version requirement). This will fail if sphinx-build is too old.
>>   run_command('mkdir', ['-p', tmpdir / 'sphinx'])
>>   run_command('touch', [tmpdir / 'sphinx/index.rst'])
>>   sphinx_build_test_out = run_command(SPHINX_ARGS + [
>>     '-c', meson.current_source_dir() / 'docs',
>>     '-b', 'html', tmpdir / 'sphinx',
>>     tmpdir / 'sphinx/out'])
>>   build_docs = (sphinx_build_test_out.returncode() == 0)
>> endif
> There is subtle error here, when  sphinx_build not found, there is
> SPHINX_ARGS  should be [],
> otherwise, latter place using  SPHINX_ARGS  have not found sphinx_build
> will cause error by meson
> ..
> I'll add
> 
> else
>   SPHINX_ARGS  = []  
> endif

All uses of SPHINX_ARGS are protected by build_docs, and in turn
build_docs is false if "not sphinx_build.found()".  Am I missing something?

Paolo