Make build python3-only compatible for distributions that want that

0001-build-sys-Use-python3-for-libdnf-by-default-if-avail.patch

@@ -0,0 +1,61 @@
+From 696cad7df63dad0ba89a9f2fdfdd05cdf02c0ada Mon Sep 17 00:00:00 2001
+From: Colin Walters <walters@verbum.org>
+Date: Mon, 16 Jul 2018 15:05:37 -0400
+Subject: [PATCH] build-sys: Use python3 for libdnf by default if available
+
+Probably at some point libdnf will drop py2 support, but the
+main reason I'm doing this is avoids a python2 dependency
+for rpm-ostree for distributions that don't want that.
+---
+ configure.ac | 22 ++++++++++++++++++++++
+ 1 file changed, 22 insertions(+)
+
+diff --git a/configure.ac b/configure.ac
+index 66c4a933..043115a6 100644
+--- a/configure.ac
++++ b/configure.ac
+@@ -113,6 +113,23 @@ AS_IF([pkg-config --atleast-version=4.13.0.1 rpm], [
+ 
+ AC_PATH_PROG([XSLTPROC], [xsltproc])
+ 
++dnl This was painful to figure out; it's sad that Automake's
++dnl python support doesn't do a better job of optionally supporting
++dnl both 2 and 3.  Anyways the logic here is: Honor $PYTHON if set
++dnl uncondionally, otherwise try python3 if it appears to be available
++dnl first, then fall back to 2.
++dnl Recommendation is explicit PYTHON=python3 ./configure ...
++AS_IF([test -z "$PYTHON"], [
++  AS_IF([test -x /usr/bin/python3], [
++    AM_PATH_PYTHON([3.6])
++  ], [
++    AM_PATH_PYTHON([2.7])
++  ])
++])
++dnl http://maemo.org/maemo_training_material/maemo4.x/html/maemo_Application_Development_Chinook/Chapter_05_GNU_Autotools.html
++dnl incorrectly says the quoted ']' is @>:@ (...crying...)
++pyver=$($PYTHON -c "import sys; sys.stdout.write(sys.version @<:@ :3 @:>@ )")
++
+ GLIB_TESTS
+ LIBGLNX_CONFIGURE
+ 
+@@ -226,6 +243,10 @@ else
+   export cmake_args
+ fi  
+ 
++case $pyver in
++  3.*) cmake_args="${cmake_args} -DPYTHON_DESIRED:str=3";;
++esac
++
+ dnl I picked /usr/libexec/rpm-ostree just because we need an
+ dnl arbitrary path - we don't actually install there.
+ (set -euo pipefail; mkdir -p libdnf-build && cd libdnf-build &&
+@@ -257,5 +278,6 @@ echo "
+     introspection:                           $found_introspection
+     bubblewrap:                              $with_bubblewrap
+     gtk-doc:                                 $enable_gtk_doc
++    python:                                  $PYTHON $pyver
+     rust:                                    $enable_rust
+ "
+-- 
+2.17.1
+

rpm-ostree.spec

@@ -14,6 +14,7 @@ Release: 3%{?dist}
 # This tarball is generated via "cd packaging && make -f Makefile.dist-packaging dist-snapshot"
 # in the upstream git.  If rust is enabled, it contains vendored sources.
 Source0: rpm-ostree-%{version}.tar.xz
+Patch1: 0001-build-sys-Use-python3-for-libdnf-by-default-if-avail.patch
 License: LGPLv2+
 URL: https://github.com/projectatomic/rpm-ostree
 
@@ -53,12 +54,13 @@ BuildRequires: pkgconfig(librepo)
 BuildRequires: cmake
 BuildRequires: pkgconfig(expat)
 BuildRequires: pkgconfig(check)
-BuildRequires: python2-devel
 # https://github.com/CentOS/sig-atomic-buildscripts/issues/324
 %if (0%{?rhel} != 0 && 0%{?rhel} <= 7)
+BuildRequires: python-devel
 BuildRequires: python-sphinx
 %else
-BuildRequires: python2-sphinx
+BuildRequires: python3-sphinx
+BuildRequires: python3-devel
 %endif
 %if (0%{?rhel} != 0 && 0%{?rhel} <= 7)
 BuildRequires: libsolv-devel
@@ -127,7 +129,6 @@ find $RPM_BUILD_ROOT -name '*.la' -delete
 # way the same spec file works more easily across multiple versions where e.g. an
 # older version might not have a systemd unit file.
 cat > autofiles.py <<EOF
-#!/usr/bin/python
 import os,sys,glob
 os.chdir(os.environ['RPM_BUILD_ROOT'])
 for line in sys.argv[1:]:
@@ -143,7 +144,11 @@ for line in sys.argv[1:]:
         else:
             sys.stderr.write('{0} did not match any files\n'.format(line))
 EOF
-python autofiles.py > files \
+PYTHON=python3
+if ! test -x /usr/bin/python3; then
+    PYTHON=python2
+fi
+$PYTHON autofiles.py > files \
   '%{_bindir}/*' \
   '%{_libdir}/%{name}' \
   '%{_mandir}/man*/*' \
@@ -154,11 +159,11 @@ python autofiles.py > files \
   '%{_datadir}/polkit-1/actions/*.policy' \
   '%{_datadir}/dbus-1/system-services'
 
-python autofiles.py > files.lib \
+$PYTHON autofiles.py > files.lib \
   '%{_libdir}/*.so.*' \
   '%{_libdir}/girepository-1.0/*.typelib'
 
-python autofiles.py > files.devel \
+$PYTHON autofiles.py > files.devel \
   '%{_libdir}/lib*.so' \
   '%{_includedir}/*' \
   '%{_datadir}/dbus-1/interfaces/org.projectatomic.rpmostree1.xml' \
@@ -174,8 +179,8 @@ python autofiles.py > files.devel \
 %files devel -f files.devel
 
 %changelog
-* Sat Jul 14 2018 Fedora Release Engineering <releng@fedoraproject.org> - 2018.6-3
+* Mon Jul 16 2018 Colin Walters <walters@verbum.org> - 2018.6-3
-- Rebuilt for https://fedoraproject.org/wiki/Fedora_29_Mass_Rebuild
+- Make build python3-only compatible for distributions that want that
 
 * Fri Jun 29 2018 Jonathan Lebon <jonathan@jlebon.com> - 2018.6-2
 - Rebuild for yummy Rusty bitsy