From 068d299fadbc2a3f722badc7646fa3f9f8ce606f Mon Sep 17 00:00:00 2001
From: Grzegorz Kowalski <g.kowalski@helium-embedded.org>
Date: Fri, 15 Mar 2024 18:19:13 +0100
Subject: [PATCH] pytango: document build process

---
 recipes-python/pytango/python3-pytango.inc | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/recipes-python/pytango/python3-pytango.inc b/recipes-python/pytango/python3-pytango.inc
index 6b71f19..efbccbd 100644
--- a/recipes-python/pytango/python3-pytango.inc
+++ b/recipes-python/pytango/python3-pytango.inc
@@ -8,6 +8,13 @@ RDEPENDS:${PN} = "python3 python3-numpy python3-packaging"
 # for toolchain.cmake file
 inherit cmake
 inherit python3targetconfig pkgconfig pypi python_pep517
+# The classes inheritance and build process here is a bit tricky.
+# PyTango uses python build (PEP517) which runs the build using
+# scikit-build-core which in turn uses CMake to build the extension.
+# So first we inherit cmake to generate cmake configuration (toolchain.cmake)
+# and then we also inherit python_pep517 to overwrite
+# do_configure/do_compile/do_install with the correct ones.
+# This almost works, but you have to play a bit with CMAKE_ARGS.
 
 # TODO: Why is python include dir not found automatically?
 export CMAKE_ARGS = "-DCMAKE_TOOLCHAIN_FILE=${WORKDIR}/toolchain.cmake -DPython_INCLUDE_DIR=${STAGING_DIR_TARGET}${includedir}/${PYTHON_DIR}"