Re: [PATCH 0/7] python: create installable package

[Philippe Mathieu-Daudé]

On 6/18/20 11:23 AM, Kevin Wolf wrote:
> Am 17.06.2020 um 22:27 hat John Snow geschrieben:
>>> In the Avocado project, we have a `make develop` rule that does that
>>> for the main setup.py file, and for all plugins we carry on the same
>>> tree, which is similar in some regards to the "not at the project root
>>> directory" situation here with "qemu/python/setup.py".
>>>
>>
>> Ah, yeah. If we're going this far, I'd prefer using a VENV over
>> modifying the user's environment. That way you can blast it all away
>> with a `make distclean`.
>>
>> Maybe the "make develop" target could even use the presence of a .venv
>> directory to know when it needs to make the environment or not ...
> [..]
>> For QEMU developers, installing with develop is going to be the smart
>> way to go. When your git tree is updated, your package will be updated
>> along with it. You can do it once and then probably forget about it.
> 
> I don't think we can make this a manual step at all. Building QEMU
> requires running some Python scripts (e.g. the QAPI generator), so the
> setup needs to be done either in configure or in a Makefile target that
> is specified as a dependency of any rule that would run a Python script.
> Building QEMU once would then be enough.
> 
> Doing it automatically also means that we have to keep things local to
> the QEMU directory rather than installing them globally into the user
> directory. This is desirable anyway: Most of us deal with more than one
> QEMU source tree, so conflicts would be inevitable.

Indeed. Each of the source tree I use has its own virtual environment.
I personally stopped using the distribution packages, they don't make
sense when you develop, the tree changes too quickly.

Distributions use stable releases, so IMO it only makes sense to
generate a package along with releases. Else use venv.