[gentoo-python] [PATCH] Introduce python_setup() as a common name for Python setup function.

[Michał Górny]

As described in the ml, the new function does:

* in python-any-r1, choose and set up the best installed impl,

* in python-single-r1, read PYTHON_SINGLE_TARGET and set it up,

* in python-r1, call python_export_best + python_wrapper_setup.

In other words, it's a common way of getting Python build environment
set up in the ebuild scope.
---
 eclass/python-any-r1.eclass    | 24 +++++++++++++++++-------
 eclass/python-r1.eclass        | 15 +++++++++++++++
 eclass/python-single-r1.eclass | 17 +++++++++++++----
 3 files changed, 45 insertions(+), 11 deletions(-)

diff --git a/eclass/python-any-r1.eclass b/eclass/python-any-r1.eclass
index 760e8e7..109c4ee 100644
--- a/eclass/python-any-r1.eclass
+++ b/eclass/python-any-r1.eclass
@@ -259,17 +259,15 @@ _python_EPYTHON_supported() {
 	return 1
 }
 
-# @FUNCTION: python-any-r1_pkg_setup
+# @FUNCTION: python_setup
 # @DESCRIPTION:
 # Determine what the best installed (and supported) Python
-# implementation is and set EPYTHON and PYTHON accordingly.
-python-any-r1_pkg_setup() {
+# implementation is, and set the Python build environment up for it.
+#
+# This function will call python_check_deps() if defined.
+python_setup() {
 	debug-print-function ${FUNCNAME} "${@}"
 
-	# avoid looking up Python for binary package install.
-	# if you need Python during pkg_preinst/_postinst, please let us know.
-	[[ ${MERGE_TYPE} == binary ]] && return 0
-
 	# first, try ${EPYTHON}... maybe it's good enough for us.
 	if [[ ${EPYTHON} ]]; then
 		if _python_EPYTHON_supported "${EPYTHON}"; then
@@ -317,5 +315,17 @@ python-any-r1_pkg_setup() {
 	die "No supported Python implementation installed."
 }
 
+# @FUNCTION: python-any-r1_pkg_setup
+# @DESCRIPTION:
+# Runs python_setup during from-source installs.
+#
+# In a binary package installs is a no-op. If you need Python in pkg_*
+# phases of a binary package, call python_setup directly.
+python-any-r1_pkg_setup() {
+	debug-print-function ${FUNCNAME} "${@}"
+
+	[[ ${MERGE_TYPE} != binary ]] && python_setup
+}
+
 _PYTHON_ANY_R1=1
 fi
diff --git a/eclass/python-r1.eclass b/eclass/python-r1.eclass
index 750fa91..1a04d5b 100644
--- a/eclass/python-r1.eclass
+++ b/eclass/python-r1.eclass
@@ -712,6 +712,21 @@ python_parallel_foreach_impl() {
 	multibuild_parallel_foreach_variant _python_multibuild_wrapper "${@}"
 }
 
+# @FUNCTION: python_setup
+# @DESCRIPTION:
+# Find the best (most preferred) Python implementation enabled
+# and set the Python build environment up for it.
+#
+# This function needs to be used when Python is being called outside
+# of python_foreach_impl calls (e.g. for shared processes like doc
+# building). python_foreach_impl sets up the build environment itself.
+python_setup() {
+	debug-print-function ${FUNCNAME} "${@}"
+
+	python_export_best
+	python_wrapper_setup
+}
+
 # @FUNCTION: python_export_best
 # @USAGE: [<variable>...]
 # @DESCRIPTION:
diff --git a/eclass/python-single-r1.eclass b/eclass/python-single-r1.eclass
index 30bbab4..5ff3d40 100644
--- a/eclass/python-single-r1.eclass
+++ b/eclass/python-single-r1.eclass
@@ -202,11 +202,11 @@ _python_single_set_globals() {
 }
 _python_single_set_globals
 
-# @FUNCTION: python-single-r1_pkg_setup
+# @FUNCTION: python_setup
 # @DESCRIPTION:
-# Determine what the selected Python implementation is and set EPYTHON
-# and PYTHON accordingly.
-python-single-r1_pkg_setup() {
+# Determine what the selected Python implementation is and set
+# the Python build environment up for it.
+python_setup() {
 	debug-print-function ${FUNCNAME} "${@}"
 
 	unset EPYTHON
@@ -250,6 +250,15 @@ python-single-r1_pkg_setup() {
 	fi
 }
 
+# @FUNCTION: python-single-r1_pkg_setup
+# @DESCRIPTION:
+# Runs python_setup.
+python-single-r1_pkg_setup() {
+	debug-print-function ${FUNCNAME} "${@}"
+
+	python_setup
+}
+
 # @FUNCTION: python_fix_shebang
 # @USAGE: <path>...
 # @DESCRIPTION:
-- 
1.8.4