Support and use out-of-source builds by default.

2 files changed, 50 insertions, 7 deletions

diff --git a/eclass/ChangeLog b/eclass/ChangeLog
index e3cee6611977..4cdc4617f4e7 100644
--- a/eclass/ChangeLog
+++ b/eclass/ChangeLog
@@ -1,6 +1,9 @@
 # ChangeLog for eclass directory
 # Copyright 1999-2012 Gentoo Foundation; Distributed under the GPL v2
-# $Header: /var/cvsroot/gentoo-x86/eclass/ChangeLog,v 1.483 2012/10/29 13:30:48 mgorny Exp $
+# $Header: /var/cvsroot/gentoo-x86/eclass/ChangeLog,v 1.484 2012/10/29 13:34:02 mgorny Exp $
+
+  29 Oct 2012; Michał Górny <mgorny@gentoo.org> distutils-r1.eclass:
+  Support and use out-of-source builds by default.
 
   29 Oct 2012; Michał Górny <mgorny@gentoo.org> distutils-r1.eclass:
   Introduce an esetup.py wrapper function and mydistutilsargs=() for it.
diff --git a/eclass/distutils-r1.eclass b/eclass/distutils-r1.eclass
index 9b427f669a6e..172cc70f39da 100644
--- a/eclass/distutils-r1.eclass
+++ b/eclass/distutils-r1.eclass
@@ -1,6 +1,6 @@
 # Copyright 1999-2012 Gentoo Foundation
 # Distributed under the terms of the GNU General Public License v2
-# $Header: /var/cvsroot/gentoo-x86/eclass/distutils-r1.eclass,v 1.13 2012/10/29 13:30:48 mgorny Exp $
+# $Header: /var/cvsroot/gentoo-x86/eclass/distutils-r1.eclass,v 1.14 2012/10/29 13:34:02 mgorny Exp $
 
 # @ECLASS: distutils-r1
 # @MAINTAINER:
@@ -105,6 +105,22 @@ DEPEND=${PYTHON_DEPS}
 # HTML_DOCS=( doc/html/ )
 # @CODE
 
+# @ECLASS-VARIABLE: DISTUTILS_IN_SOURCE_BUILD
+# @DEFAULT_UNSET
+# @DESCRIPTION:
+# If set to a non-null value, in-source builds will be enabled.
+# If unset, the default is to use in-source builds when python_prepare()
+# is declared, and out-of-source builds otherwise.
+#
+# If in-source builds are used, the eclass will create a copy of package
+# sources for each Python implementation in python_prepare_all(),
+# and work on that copy afterwards.
+#
+# If out-of-source builds are used, the eclass will instead work
+# on the sources directly, prepending setup.py arguments with
+# 'build --build-base ${BUILD_DIR}' to enforce keeping & using built
+# files in the specific root.
+
 # @ECLASS-VARIABLE: mydistutilsargs
 # @DEFAULT_UNSET
 # @DESCRIPTION:
@@ -129,8 +145,17 @@ DEPEND=${PYTHON_DEPS}
 esetup.py() {
 	debug-print-function ${FUNCNAME} "${@}"
 
+	local args=()
+	if [[ ! ${DISTUTILS_IN_SOURCE_BUILD} ]]; then
+		if [[ ! ${BUILD_DIR} ]]; then
+			die 'Out-of-source build requested, yet BUILD_DIR unset.'
+		fi
+
+		args+=( build --build-base "${BUILD_DIR}" )
+	fi
+
 	set -- "${PYTHON:-python}" setup.py \
-		"${mydistutilsargs[@]}" "${@}"
+		"${args[@]}" "${mydistutilsargs[@]}" "${@}"
 
 	echo "${@}" >&2
 	"${@}" || die
@@ -151,8 +176,17 @@ distutils-r1_python_prepare_all() {
 
 	epatch_user
 
-	# create source copies for each implementation
-	python_copy_sources
+	# by default, use in-source build if python_prepare() is used
+	if [[ ! ${DISTUTILS_IN_SOURCE_BUILD+1} ]]; then
+		if declare -f python_prepare >/dev/null; then
+			DISTUTILS_IN_SOURCE_BUILD=1
+		fi
+	fi
+
+	if [[ ${DISTUTILS_IN_SOURCE_BUILD} ]]; then
+		# create source copies for each implementation
+		python_copy_sources
+	fi
 }
 
 # @FUNCTION: distutils-r1_python_prepare
@@ -296,9 +330,15 @@ distutils-r1_python_install_all() {
 distutils-r1_run_phase() {
 	debug-print-function ${FUNCNAME} "${@}"
 
-	pushd "${BUILD_DIR}" &>/dev/null || die
+	if [[ ${DISTUTILS_IN_SOURCE_BUILD} ]]; then
+		pushd "${BUILD_DIR}" &>/dev/null || die
+	fi
+
 	"${@}" || die "${1} failed."
-	popd &>/dev/null || die
+
+	if [[ ${DISTUTILS_IN_SOURCE_BUILD} ]]; then
+		popd &>/dev/null || die
+	fi
 }
 
 distutils-r1_src_prepare() {