Make python changes more reliable

We oneshot emerge without calculating dependencies a few things to solve
for possible dependency loops.

Python 3.5 also became stable, so don't need to do special things for
it.

Matched the uninstall with the install lines (no need for a full if
statement).

Change-Id: I7c5e546612ac47d659e73a46a52e34d39ca81949

diskimage_builder/elements/gentoo/pre-install.d/10-install-desired-python

@@ -33,12 +33,7 @@ if [[ "${GENTOO_PYTHON_TARGETS}" == *"python3_6"* ]]; then
     echo '~sys-apps/kmod-24 ~amd64' >> /etc/portage/package.keywords/python
     [[ ! -e /usr/lib64/libpython3.6m.so ]] && USE="-build" emerge -1q --jobs=2 dev-lang/python:3.6
 fi
-if [[ "${GENTOO_PYTHON_TARGETS}" == *"python3_5"* ]]; then
+[[ "${GENTOO_PYTHON_TARGETS}" == *"python3_5"* ]] && [[ ! -e /usr/lib64/libpython3.5m.so ]] && USE="-build" emerge -1q --jobs=2 dev-lang/python:3.5
-    echo -e "-python_targets_python3_5\n-python_single_target_python3_5" >> /etc/portage/profile/use.stable.mask
-    echo 'dev-lang/python:3.5 ~amd64' >> /etc/portage/package.keywords/python
-    echo '~dev-python/setuptools-36.0.1 ~amd64' >> /etc/portage/package.keywords/python
-    [[ ! -e /usr/lib64/libpython3.5m.so ]] && USE="-build" emerge -1q --jobs=2 dev-lang/python:3.5
-fi
 [[ "${GENTOO_PYTHON_TARGETS}" == *"python3_4"* ]] && [[ ! -e /usr/lib64/libpython3.4m.so ]] && USE="-build" emerge -1q --jobs=2 dev-lang/python:3.4
 [[ "${GENTOO_PYTHON_TARGETS}" == *"python2_7"* ]] && [[ ! -e /usr/lib64/libpython2.7.so ]] && USE="-build" emerge -1q --jobs=2 dev-lang/python:2.7
 # disable python in git if we have to, it only supports python-2.7
@@ -46,23 +41,20 @@ if [[ "${GENTOO_PYTHON_TARGETS}" != *"python2_7"* ]]; then
     echo 'dev-vcs/git -python' >> /etc/portage/package.use/git
 fi
 # make sure we have the new python for portage bevore we possibly remove python 2.7
-USE="-build" emerge -q --oneshot --jobs=2 --with-bdeps=y --update --newuse --deep sys-apps/portage dev-python/pyxattr
+# this is done one by one with nodeps because it can sometimes have dependency loops
+PYTHON_PACKAGES="dev-python/six dev-python/packaging dev-python/pyparsing dev-python/appdirs dev-python/setuptools dev-python/certifi"
+for PACKAGE in ${PYTHON_PACKAGES}; do
+    USE="-build" emerge -q --oneshot --jobs=2 --with-bdeps=y --update --newuse --deep --nodeps "${PACKAGE}"
+done
+USE="-build" emerge -q --oneshot --jobs=2 --with-bdeps=y --update --newuse --deep --complete-graph=y sys-apps/portage dev-python/pyxattr
 # set the active python version
 eselect python set ${GENTOO_PYTHON_ACTIVE_VERSION}
 # allow these uninstalls to fail as they may not be installed to begin with
 set +e
-if [[ "${GENTOO_PYTHON_TARGETS}" != *"python2_7"* ]]; then
+[[ "${GENTOO_PYTHON_TARGETS}" != *"python2_7"* ]] && emerge -C -q dev-lang/python:2.7
-    emerge -C -q dev-lang/python:2.7
+[[ "${GENTOO_PYTHON_TARGETS}" != *"python3_4"* ]] && emerge -C -q dev-lang/python:3.4
-fi
+[[ "${GENTOO_PYTHON_TARGETS}" != *"python3_5"* ]] && emerge -C -q dev-lang/python:3.5
-if [[ "${GENTOO_PYTHON_TARGETS}" != *"python3_4"* ]]; then
+[[ "${GENTOO_PYTHON_TARGETS}" != *"python3_6"* ]] && emerge -C -q dev-lang/python:3.6
-    emerge -C -q dev-lang/python:3.4
-fi
-if [[ "${GENTOO_PYTHON_TARGETS}" != *"python3_5"* ]]; then
-    emerge -C -q dev-lang/python:3.5
-fi
-if [[ "${GENTOO_PYTHON_TARGETS}" != *"python3_6"* ]]; then
-    emerge -C -q dev-lang/python:3.6
-fi
 set -e
 
 # make world consistant
@@ -74,5 +66,4 @@ USE="-build" emerge --verbose=n --depclean
 # rebuild packages that might have somehow depended on the unneeded packages
 USE="-build" emerge -q --jobs=2 --usepkg=n @preserved-rebuild
 
-
 unfix_shm