python-twisted: avoid downloading build dependencies

setup.py will attempt to download python-incremental, as it is not
present in the sysroot. This is at the least wrong since some random
version of python-incremental will be used to build against (akin to
host contamination) and at most a build failure (when network access
is unavailable). So make python-incrementa-native available and a
DEPENDS.

Unfortunately python-incremental has a dependency on python-twisted
and vice versa. So we need to forcefully break this circular
dependency. Fortunately this doesn't affect the build of
python-twisted. Unfortunately if anyone else attempts to use
python-incremental-native there might be issues should it ever run the
code that does the import of twisted. This is not an issue now and a
comment has been added to hopefully make this issue known to anyone
else coming along at a later time.

Signed-off-by: Mark Asselstine <mark.asselstine@windriver.com>
Signed-off-by: Armin Kuster <akuster808@gmail.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/meta-python/recipes-devtools/python/python-incremental.inc b/meta-python/recipes-devtools/python/python-incremental.inc
index 367545868..b63fac979 100644
--- a/meta-python/recipes-devtools/python/python-incremental.inc
+++ b/meta-python/recipes-devtools/python/python-incremental.inc
@@ -12,3 +12,9 @@ RDEPENDS_${PN} += " \
     ${PYTHON_PN}-twisted \
     ${PYTHON_PN}-click \
 "
+
+# -native is needed to build python[3]-twisted, however, we need to take steps to
+# prevent a circular dependency. The build apparently does not use the part of
+# python-incremental which uses python-twisted, so this hack is OK.
+RDEPENDS_${PYTHON_PN}-incremental-native_remove = "${PYTHON_PN}-twisted-native"
+BBCLASSEXTEND = "native nativesdk"