[gentoo-python] [PATCH 1/3] Make python-single-r1 stand-alone.

[Michał Górny]

It's not that good idea to inherit python-r1 there, so let's just make
it work on its own.

Also, duplicate the docs so that people could find them easily.
---
 gx86/eclass/python-r1.eclass        |  11 ----
 gx86/eclass/python-single-r1.eclass | 114 ++++++++++++++++++++++++++++--------
 gx86/eclass/python-utils-r1.eclass  |  11 ++++
 3 files changed, 100 insertions(+), 36 deletions(-)

diff --git a/gx86/eclass/python-r1.eclass b/gx86/eclass/python-r1.eclass
index c989690..9a02df3 100644
--- a/gx86/eclass/python-r1.eclass
+++ b/gx86/eclass/python-r1.eclass
@@ -44,17 +44,6 @@ if [[ ! ${_PYTHON_R1} ]]; then
 
 inherit python-utils-r1
 
-# @ECLASS-VARIABLE: _PYTHON_ALL_IMPLS
-# @INTERNAL
-# @DESCRIPTION:
-# All supported Python implementations, most preferred last.
-_PYTHON_ALL_IMPLS=(
-	jython2_5
-	pypy1_8 pypy1_9
-	python3_1 python3_2 python3_3
-	python2_5 python2_6 python2_7
-)
-
 # @ECLASS-VARIABLE: PYTHON_COMPAT
 # @REQUIRED
 # @DESCRIPTION:
diff --git a/gx86/eclass/python-single-r1.eclass b/gx86/eclass/python-single-r1.eclass
index 1fdf803..3aa350b 100644
--- a/gx86/eclass/python-single-r1.eclass
+++ b/gx86/eclass/python-single-r1.eclass
@@ -23,9 +23,10 @@
 # (using python-r1 eclass) can not depend on packages not supporting
 # them (using this eclass).
 #
-# Also, please note that python-single-r1 will always inherit python-r1
-# as well. Thus, all the variables defined there are relevant
-# to the packages using python-single-r1.
+# Please note that python-r1 will always inherit python-utils-r1 as
+# well. Thus, all the functions defined there can be used
+# in the packages using python-r1, and there is no need ever to inherit
+# both.
 #
 # For more information, please see the python-r1 Developer's Guide:
 # http://www.gentoo.org/proj/en/Python/python-r1/dev-guide.xml
@@ -44,7 +45,7 @@ esac
 
 if [[ ! ${_PYTHON_SINGLE_R1} ]]; then
 
-inherit python-r1
+inherit python-utils-r1
 
 fi
 
@@ -52,13 +53,89 @@ EXPORT_FUNCTIONS pkg_setup
 
 if [[ ! ${_PYTHON_SINGLE_R1} ]]; then
 
+# @ECLASS-VARIABLE: PYTHON_COMPAT
+# @REQUIRED
+# @DESCRIPTION:
+# This variable contains a list of Python implementations the package
+# supports. It must be set before the `inherit' call. It has to be
+# an array.
+#
+# Example:
+# @CODE
+# PYTHON_COMPAT=( python{2_5,2_6,2_7} )
+# @CODE
+if ! declare -p PYTHON_COMPAT &>/dev/null; then
+	die 'PYTHON_COMPAT not declared.'
+fi
+
+# @ECLASS-VARIABLE: PYTHON_REQ_USE
+# @DEFAULT_UNSET
+# @DESCRIPTION:
+# The list of USEflags required to be enabled on the chosen Python
+# implementations, formed as a USE-dependency string. It should be valid
+# for all implementations in PYTHON_COMPAT, so it may be necessary to
+# use USE defaults.
+#
+# Example:
+# @CODE
+# PYTHON_REQ_USE="gdbm,ncurses(-)?"
+# @CODE
+#
+# It will cause the Python dependencies to look like:
+# @CODE
+# python_single_target_pythonX_Y? ( dev-lang/python:X.Y[gdbm,ncurses(-)?] )
+# @CODE
+
+# @ECLASS-VARIABLE: PYTHON_DEPS
+# @DESCRIPTION:
+# This is an eclass-generated Python dependency string for all
+# implementations listed in PYTHON_COMPAT.
+#
+# The dependency string is conditional on PYTHON_SINGLE_TARGET.
+#
+# Example use:
+# @CODE
+# RDEPEND="${PYTHON_DEPS}
+#	dev-foo/mydep"
+# DEPEND="${RDEPEND}"
+# @CODE
+#
+# Example value:
+# @CODE
+# dev-python/python-exec
+# python_single_target_python2_6? ( dev-lang/python:2.6[gdbm] )
+# python_single_target_python2_7? ( dev-lang/python:2.7[gdbm] )
+# @CODE
+
+# @ECLASS-VARIABLE: PYTHON_USEDEP
+# @DESCRIPTION:
+# This is an eclass-generated USE-dependency string which can be used to
+# depend on another Python package being built for the same Python
+# implementations.
+#
+# The generate USE-flag list is compatible with packages using python-r1,
+# python-single-r1 and python-distutils-ng eclasses. It must not be used
+# on packages using python.eclass.
+#
+# Example use:
+# @CODE
+# RDEPEND="dev-python/foo[${PYTHON_USEDEP}]"
+# @CODE
+#
+# Example value:
+# @CODE
+# python_targets_python2_7?,python_single_target_python2_7(+)?
+# @CODE
+
 _python_single_set_globals() {
+	local flags_mt=( "${PYTHON_COMPAT[@]/#/python_targets_}" )
 	local flags=( "${PYTHON_COMPAT[@]/#/python_single_target_}" )
-	local optflags=${flags[@]/%/(+)?}
+	local optflags=${flags_mt[@]/%/?}
+	optflags+=,${flags[@]/%/(+)?}
 
-	IUSE=${flags[*]}
-	REQUIRED_USE="^^ ( ${flags[*]} )"
-	PYTHON_USEDEP+=,${optflags// /,}
+	IUSE="${flags_mt[*]} ${flags[*]}"
+	REQUIRED_USE="|| ( ${flags_mt[*]} ) ^^ ( ${flags[*]} )"
+	PYTHON_USEDEP=${optflags// /,}
 
 	local usestr
 	[[ ${PYTHON_REQ_USE} ]] && usestr="[${PYTHON_REQ_USE}]"
@@ -88,6 +165,10 @@ _python_single_set_globals() {
 }
 _python_single_set_globals
 
+# @FUNCTION: python-single-r1_pkg_setup
+# @DESCRIPTION:
+# Determine what the selected Python implementation is and set EPYTHON
+# and PYTHON accordingly.
 python-single-r1_pkg_setup() {
 	debug-print-function ${FUNCNAME} "${@}"
 
@@ -101,20 +182,3 @@ python-single-r1_pkg_setup() {
 		fi
 	done
 }
-
-# Incompatible python-r1 functions.
-
-python_copy_sources() {
-	die "${FUNCNAME} must not be used with python-single-r1 eclass."
-}
-
-python_foreach_impl() {
-	die "${FUNCNAME} must not be used with python-single-r1 eclass."
-}
-
-python_export_best() {
-	die "${FUNCNAME} must not be used with python-single-r1 eclass."
-}
-
-_PYTHON_SINGLE_R1=1
-fi
diff --git a/gx86/eclass/python-utils-r1.eclass b/gx86/eclass/python-utils-r1.eclass
index d8e4b81..113e977 100644
--- a/gx86/eclass/python-utils-r1.eclass
+++ b/gx86/eclass/python-utils-r1.eclass
@@ -40,6 +40,17 @@ if [[ ! ${_PYTHON_UTILS_R1} ]]; then
 
 inherit multilib
 
+# @ECLASS-VARIABLE: _PYTHON_ALL_IMPLS
+# @INTERNAL
+# @DESCRIPTION:
+# All supported Python implementations, most preferred last.
+_PYTHON_ALL_IMPLS=(
+	jython2_5
+	pypy1_8 pypy1_9
+	python3_1 python3_2 python3_3
+	python2_5 python2_6 python2_7
+)
+
 # @ECLASS-VARIABLE: PYTHON
 # @DESCRIPTION:
 # The absolute path to the current Python interpreter.
-- 
1.8.0