[gentoo-user] Re: Can't install cairosvg

[Grant Edwards]

On 2016-06-01, Neil Bothwick <neil@××××××××××.uk> wrote:
> On Tue, 31 May 2016 22:05:24 +0000 (UTC), Grant Edwards wrote:
>
>>  emerge: there are no ebuilds to satisfy
>> "dev-python/cairocffi[python_targets_python2_7(-)?,python_targets_python3_3(-)?,python_targets_python3_4(-)?,python_targets_python3_5(-)?,-python_single_target_python2_7(-),-python_single_target_python3_3(-),-python_single_target_python3_4(-),-python_single_target_python3_5(-)]".
>> (dependency required by "media-gfx/cairosvg-1.0.7::gentoo" [ebuild])
>> (dependency required by "cairosvg" [argument])
>>
>> I've tried dozens of settings for PYTHON_TARGETS and
>> PYTHON_SINGLE_TARGET and have gotten exactly nowhere.  Is there an
>> English translation of the emerge error message available?
>
> It appears to be complaining about the python settings for cairocffi,
> what does eix -v cairocffi show?

# eix -v cairocffi
* dev-python/cairocffi
     Available versions:  ~0.5.3-r1 ~0.5.4 ~0.6
     IUSE (all versions): doc test PYTHON_TARGETS="pypy python2_7 python3_3 python3_4"
     Installed versions:  Version:   0.7.2
                          Date:      05:30:14 PM 05/31/2016
                          USE:       -doc -test PYTHON_TARGETS="python2_7 python3_4 -pypy -python3_3 -python3_5"
                          DEPEND:    dev-python/setuptools[python_targets_python2_7(-),python_targets_python3_4(-),-python_single_target_pypy(-),-python_single_target_python2_7(-),-python_single_target_python3_3(-),-python_single_target_python3_4(-),-python_single_target_python3_5(-)] >=dev-lang/python-2.7.5-r2:2.7 dev-lang/python:3.4 >=dev-lang/python-exec-2:2/2=[python_targets_python2_7(-),python_targets_python3_4(-),-python_single_target_pypy(-),-python_single_target_python2_7(-),-python_single_target_python3_3(-),-python_single_target_python3_4(-),-python_single_target_python3_5(-)]
                          RDEPEND:   >=dev-python/cffi-1.1.0:0/1.5.2=[python_targets_python2_7(-),-python_single_target_python2_7(-),-python_single_target_python3_3(-),python_targets_python3_4(-),-python_single_target_python3_4(-),-python_single_target_python3_5(-)] >=dev-python/cffi-1.1.0:0/1.5.2=[python_targets_python2_7(-),-python_single_target_python2_7(-),-python_single_target_python3_3(-),python_targets_python3_4(-),-python_single_target_python3_4(-),-python_single_target_python3_5(-)] >=dev-python/xcffib-0.3.2[python_targets_python2_7(-),python_targets_python3_4(-),-python_single_target_pypy(-),-python_single_target_python2_7(-),-python_single_target_python3_3(-),-python_single_target_python3_4(-),-python_single_target_python3_5(-)] x11-libs/cairo:0/0= x11-libs/gdk-pixbuf[jpeg] >=dev-lang/python-2.7.5-r2:2.7 dev-lang/python:3.4 >=dev-lang/python-exec-2:2/2=[python_targets_python2_7(-),python_targets_python3_4(-),-python_single_target_pypy(-),-python_single_target_python2_7(-),
 -python_single_target_python3_3(-),-python_single_target_python3_4(-),-python_single_target_python3_5(-)]
                          EAPI:      5
     Recommendation:      Downgrade
     Homepage:            https://github.com/SimonSapin/cairocffi
     Find open bugs:      https://bugs.gentoo.org/buglist.cgi?quicksearch=dev-python%2Fcairocffi
     Description:         CFFI-based drop-in replacement for Pycairo
     License:             BSD

Yep.  The problem appears to be that cairocffi is not installed for
3.5.  so python target 3.5 has to be disable for things that depend on
cairocffi.

So this in packagtes.use allows cairosvg to install:

  media-gfx/cairosvg     PYTHON_TARGETS: -python3_5

I'm still trying to figure out why cairocffi won't install for 3.5.
It's ebuild seems to think it should -- this is from
cairocffi-0.7.2.ebuild:

  PYTHON_COMPAT=( python2_7 python3_{3,4,5} pypy )

And here's what's in make.conf:

  PYTHON_TARGETS="python2_7 python3_4 python3_5"

But when I install cairocffi:

 # emerge -av cairocffi

 These are the packages that would be merged, in order:

 Calculating dependencies... done!
 [ebuild   R    ] dev-python/cairocffi-0.7.2::gentoo  USE="-doc {-test}" PYTHON_TARGETS="python2_7 python3_4 (-pypy) -python3_3 (-python3_5)" 0 KiB

 Total: 1 package (1 reinstall), Size of downloads: 0 KiB

I don't actually _need_ cairocffi/cairosvg for any particular Python
version, since all I wanted them for was to install weasyprint (and I
don't care which version of Python it uses).

But I'd still like to understand what's going on.

-- 
Grant Edwards               grant.b.edwards        Yow! This PIZZA symbolizes
                                  at               my COMPLETE EMOTIONAL
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