Signed-off-by: Michał Górny <mgo...@gentoo.org>
---
eclass/distutils-r1.eclass | 35 +++++++++++++++++++++++++++++------
1 file changed, 29 insertions(+), 6 deletions(-)
diff --git a/eclass/distutils-r1.eclass b/eclass/distutils-r1.eclass
index d32e5929177e..7dfc8c7a3c30 100644
--- a/eclass/distutils-r1.eclass
+++ b/eclass/distutils-r1.eclass
@@ -134,13 +134,20 @@
#
# - sip - sipbuild backend
#
-# - standalone - standalone build systems without external deps
-# (used for bootstrapping).
+# - standalone - standalone/local build systems
#
# - uv-build - uv-build backend (using dev-python/uv)
#
-# The variable needs to be set before the inherit line. The eclass
-# adds appropriate build-time dependencies and verifies the value.
+# The variable needs to be set before the inherit line. If another
+# value than "standalone" and "no" is used, The eclass adds appropriate
+# build-time dependencies, verifies the value and calls the appropriate
+# modern entry point for the backend. With DISTUTILS_UPSTREAM_PEP517,
+# this variable can be used to override the upstream build backend.
+#
+# The value of "standalone" indicates that upstream is using a custom,
+# local build backend. In this mode, the eclass does not add any
+# dependencies, disables build backend verification and uses the exact
+# entry point listed in pyproject.toml.
#
# The special value "no" indicates that the package has no build system.
# This is not equivalent to unset DISTUTILS_USE_PEP517 (legacy mode).
@@ -162,6 +169,12 @@
# overriden to workaround the eclass check, when it is desirable
# to build the wheel using other backend than the one used upstream.
#
+# When using it, ideally it should list the build backend actually used
+# upstream, so the eclass will throw an error if that backend changes
+# (and therefore overrides may need to change as well). As a special
+# case, setting it to "standalone" disables the check entirely (while
+# still forcing the backend, unlike DISTUTILS_USE_PEP517=standalone).
+#
# Please note that even in packages using PEP621 metadata, there can
# be subtle differences between the behavior of different PEP517 build
# backends, for example regarding finding package files. When using
@@ -1150,11 +1163,23 @@ _distutils-r1_get_backend() {
fi
fi
+ # if DISTUTILS_USE_PEP517 is "standalone", we respect the exact
+ # backend used in pyproject.toml; otherwise we force the backend
+ # based on DISTUTILS_USE_PEP517
if [[ ${DISTUTILS_USE_PEP517} == standalone ]]; then
echo "${build_backend}"
return
fi
+ # we can output it early, even if we die below
+ echo "$(_distutils-r1_key_to_backend "${DISTUTILS_USE_PEP517}")"
+
+ # skip backend verification if DISTUTILS_UPSTREAM_PEP517
+ # is "standalone"
+ if [[ ${DISTUTILS_UPSTREAM_PEP517} == standalone ]]; then
+ return
+ fi
+
# verify that the ebuild correctly specifies the build backend
local expected_backend=$(
_distutils-r1_key_to_backend \
@@ -1189,8 +1214,6 @@ _distutils-r1_get_backend() {
> "${T}"/.distutils_deprecated_backend_warned || die
fi
fi
-
- echo "$(_distutils-r1_key_to_backend "${DISTUTILS_USE_PEP517}")"
}
# @FUNCTION: distutils_wheel_install
