[Buildroot] [PATCH 3/3] package/pkg-python: use --single-version-externally-managed for host setuptools

[Yegor Yefremov]

On Sat, Dec 29, 2018 at 4:16 PM Asaf Kahlon <asafka7 at gmail.com> wrote:
>
> Hello,
>
> On Fri, Dec 28, 2018 at 7:01 PM Thomas Petazzoni
> <thomas.petazzoni at bootlin.com> wrote:
> >
> > Currently, host Python packages that use setuptools are installed as
> > Python Eggs, i.e they are installed in
> > $(HOST_DIR)/lib/python2.7/site-packages/Something-<version>.egg. Once
> > installed, each Python Egg is registered to a file called
> > $(HOST_DIR)/lib/python2.7/site-packages/easy-install.pth. This file is
> > read by the Python interpreter so that the installation location of
> > each Egg is added to the Python path, and can be found by the Python
> > interpreter.
> >
> > However, the fact that the installation of different Python modules
> > need to update a common file is clearly not compatible with
> > per-package directories and top-level parallel build.
> >
> > To fix this, we avoid using Python Eggs using the same
> > --single-version-externally-managed option that we use for target
> > modules. This option is normally meant for distributions packaging
> > Python modules, and can therefore only be used if either --record (to
> > record the list of files being installed) or --root is
> > passed. --root=/ works fine and was suggested by
> > https://stackoverflow.com/questions/6301003/stopping-setup-py-from-installing-as-egg/33791008#33791008.
> >
> > With this change, host Python modules installed by setuptools are now
> > installed in the "regular" way, i.e directly in
> > $(HOST_DIR)/lib/python2.7/site-packages/mako for host-python-mako.
> >
> > This makes the installation of host Python modules more similar to the
> > one of target modules, and makes it compatible with per-package
> > directory support and top-level parallel build.
> >
> > Signed-off-by: Thomas Petazzoni <thomas.petazzoni at bootlin.com>
> > ---
> >  package/pkg-python.mk | 4 +++-
> >  1 file changed, 3 insertions(+), 1 deletion(-)
> >
> > diff --git a/package/pkg-python.mk b/package/pkg-python.mk
> > index b641e3f865..4f42e2efc2 100644
> > --- a/package/pkg-python.mk
> > +++ b/package/pkg-python.mk
> > @@ -85,7 +85,9 @@ HOST_PKG_PYTHON_SETUPTOOLS_ENV = \
> >         PYTHONNOUSERSITE=1
> >
> >  HOST_PKG_PYTHON_SETUPTOOLS_INSTALL_OPTS = \
> > -       --prefix=$(HOST_DIR)
> > +       --prefix=$(HOST_DIR) \
> > +       --root=/ \
> > +       --single-version-externally-managed
> >
> >  ifeq ($(BR2_PER_PACKAGE_DIRECTORIES),y)
> >  define PKG_PYTHON_FIXUP_SYSCONFIGDATA
> > --
> > 2.20.1
> >
>
> Reviewed-by: Asaf Kahlon <asafka7 at gmail.com>

Reviewed-by: Yegor Yefremov <yegorslists at googlemail.com>