[gentoo-dev] [PATCH 4/8] distutils-r1.eclass: Document BUILD_DIR for consistency

["Michał Górny" <mgorny@gentoo.org>]

Closes: https://bugs.gentoo.org/910661
Signed-off-by: Michał Górny <mgorny@gentoo.org>
---
 eclass/distutils-r1.eclass | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/eclass/distutils-r1.eclass b/eclass/distutils-r1.eclass
index 2b610a4d2ceb..3d72a5d3d554 100644
--- a/eclass/distutils-r1.eclass
+++ b/eclass/distutils-r1.eclass
@@ -206,6 +206,22 @@ esac
 # the build system in pure Python packages and packages using the stable
 # Python ABI.
 
+# @ECLASS_VARIABLE: BUILD_DIR
+# @OUTPUT_VARIABLE
+# @DEFAULT_UNSET
+# @DESCRIPTION:
+# The current build directory. In global scope, it is supposed to
+# contain an initial build directory; if unset, it defaults to ${S}.
+#
+# When running in multi-impl mode, the BUILD_DIR variable is set
+# by python-r1.eclass.  Otherwise, it is set by distutils-r1.eclass
+# for consistency.
+#
+# Example value:
+# @CODE
+# ${WORKDIR}/foo-1.3-python3_12
+# @CODE
+
 if [[ -z ${_DISTUTILS_R1_ECLASS} ]]; then
 _DISTUTILS_R1_ECLASS=1
 
-- 
2.45.2