Ryan Schmidt <[email protected]> 於 2018年9月8日 週六 上午5:15寫道：
>
>
>
> On Sep 7, 2018, at 04:08, Mojca Miklavec wrote:
>
> > On Fri, 7 Sep 2018 at 10:39, Chih-Hsuan Yen wrote:
> >>
> >> Hi all,
> >>
> >> In many Python libraries, depends_lib is used to store dependencies
> >> listed in install_requires of setup.py. According to MacPorts
> >> documents, depends_lib is for dependencies that are necessary for both
> >> build-time and run-time, and depends_run is for those required in
> >> run-time only. For most Python libraries, especially pure Python ones,
> >> the build step is just copying Python sources files to a build/
> >> directory, and dependencies are not checked. So, the question is: why
> >> depends_lib is used in these cases instead of depends_run?
> >
> > My speculation is that:
> > - long time ago we had no depends_run (or at least I did not know
> > about it), so initially everything would be depends_lib anyway
>
> depends_build, depends_lib and depends_run have existed since the beginning.
>
>
> > - functionally there's absolutely no difference from the perspective
> > of the user being able to use a package
> > - in many cases nobody bothers checking or fixing those dependencies
>
> There's probably little practical difference, as far as the user is
> concerned, between depends_lib and depends_run. Either way, MacPorts will
> arrange that those ports are installed beforehand, and will prevent them from
> being uninstalled afterward. Still, there's nothing wrong with updating
> dependency types to be more correct.
>
> It's more important to get the distinction between depends_build and
> depends_lib/depends_run right. Build dependencies can be uninstalled after
> the build; library and runtime dependencies can't.
>
>
> > - pypi2port would always give you depends_lib (I'm not even sure if
> > metainformation in python packages is able to distinguish between the
> > two, and even if it is, most python package authors would not bother
> > getting this right)
> >
> > But note again that this is just my personal **speculation**.
>
> Looks like pypi2port only uses depends_build and depends_run; it does not use
> depends_lib. Seems to me like that's probably wrong, but I'm not very
> familiar with python.
>
Thank you both for explanations and reasoning! As depends_run and
depends_lib are practically the same for Python ports, how about
moving all ports to either depends_lib or depends_run gradually?
Having two patterns hurts my eyes :D
If we are moving to depends_run, just remember to keep non-Python
dependencies in depends_lib for Python packages with C extensions. For
example, in py-openssl, path:lib/libssl.dylib:openssl should be kept
in depends_lib and port:py${python.version}-cryptography and
port:py${python.version}-six can be moved to depends_run.
Regards,
Chih-Hsuan Yen
