[gentoo-dev] [PATCH 1/2] p-d-ng: split out default impl selection logic.

[Michał Górny]

Move the logic out of doscript() to make it reusable. Also, use
_PYTHON_ALL_IMPLS[@] instead of hardcoding the preference list.
---
 gx86/eclass/python-distutils-ng.eclass | 38 +++++++++++++++++++++-------------
 1 file changed, 24 insertions(+), 14 deletions(-)

diff --git a/gx86/eclass/python-distutils-ng.eclass 
b/gx86/eclass/python-distutils-ng.eclass
index 33d183c..ab13ffc 100644
--- a/gx86/eclass/python-distutils-ng.eclass
+++ b/gx86/eclass/python-distutils-ng.eclass
@@ -160,6 +160,29 @@ python-distutils-ng_doscript() {
        python-distutils-ng_newscript "${1}" "$(basename "${1}")" "${2}"
 }
 
+# Get the preferred implementation for the symlink.
+_python-distutils-ng_get_best_impl() {
+       local defimpl=${PYTHON_DEFAULT_IMPLEMENTATION}
+
+       if [[ ${defimpl} ]]; then
+               if use ${defimpl}; then
+                       echo ${defimpl}
+               else
+                       die "default implementation ${defimpl} not enabled."
+               fi
+       else
+               local impl
+               for impl in ${_PYTHON_ALL_IMPLS[@]}; do
+                       if use python_targets_${impl}; then
+                               echo "${impl}"
+                               return
+                       fi
+               done
+       fi
+
+       die "unable to find a default Python implementation."
+}
+
 # @FUNCTION: python-distutils-ng_newscript
 # @USAGE: script_file_name new_file_name [destination_directory]
 # @DESCRIPTION:
@@ -184,7 +207,7 @@ python-distutils-ng_newscript() {
        [[ -n "${2}" ]] || die "Missing destination file name"
        local source_file="${1}"
        local destination_file="${2}"
-       local default_impl="${PYTHON_DEFAULT_IMPLEMENTATION}"
+       local default_impl=$(_python-distutils-ng_get_best_impl)
        local enabled_impls=0
        local destination_directory="/usr/bin"
        [[ -n "${3}" ]] && destination_directory="${3}"
@@ -194,19 +217,6 @@ python-distutils-ng_newscript() {
                enabled_impls=$((enabled_impls + 1))
        done
 
-       if [[ -z "${default_impl}" ]]; then
-               for impl in python{2_7,2_6,2_5,3_2,3_1} pypy{1_9,1_8,1_7} 
jython2_5; do
-                       use "python_targets_${impl}" || continue
-                       default_impl="${impl}"
-                       break
-               done
-       else
-               use "python_targets_${default_impl}" || \
-                       die "default implementation ${default_impl} not enabled"
-       fi
-
-       [[ -n "${default_impl}" ]] || die "Could not select default 
implementation"
-
        dodir "${destination_directory}"
        insinto "${destination_directory}"
        if [[ "${enabled_impls}" = "1" ]]; then
-- 
1.7.12