[OE-core] [RFC PATCH] package.bbclass: improve -dbg and -src package ordering

[Rasmus Villemoes]

nativesdk-gpgme fails package_qa when setting PACKAGE_DEBUG_SPLIT_STYLE
= "debug-with-srcpkg".

ERROR: nativesdk-gpgme-1.10.0-r0 do_package_qa: QA Issue: non debug package contains .debug directory: nativesdk-python3-gpg path /work/x86_64-nativesdk-oesdk-linux/nativesdk-gpgme/1.10.0-r0/packages-split/nativesdk-python3-gpg/usr/local/oecore-x86_64/sysroots/x86_64-oesdk-linux/usr/lib/python3.5/site-packages/gpg/.debug/_gpgme.cpython-35m-x86_64-linux-gnu.so [debug-files]

This turns out to be because the automatic moving of the -dbg package to
the beginning of the package list is disabled in that case, so the
python3-gpg packages that the recipe prepends to PACKAGES ends up before
the -dbg package.

It's not clear why the "and not split_source_package" was added when
debug-with-srcpkg was introduced. Presumably the intention was to
prevent the -dbg package to end up before the -src package, which we of
course need to. But at the same time, we still need -dbg packages to end
up before all other packages.

Using list.insert(0, ...) also means that if there happens to more than
one -dbg package, their relative ordering gets inverted in the new list.

This tries to fix these issues by sorting the packages by (priority,
original position), where priority is 10 for -src, 30 for -dbg and 50
for everything else. That guarantees that packages of the same "type"
preserve their relative ordering, while also ensuring that -dbg always
preceed other packages. This scheme is also quite extensible, and,
should the need arise, one could even expose the priorities as a knob
the recipe author could use to ensure specific orderings of packages
instead of the somewhat fragile and coarse-grained method of "prepend or
append, and ensure you do that in a proper order".

Probably the autodebug condition needs to stay, but I think the
split_source_package condition in the preceding elif should be removed,
so that that logic applies to all packages called -src, not just the one
we might have created a few lines above.

Signed-off-by: Rasmus Villemoes <rasmus.villemoes at prevas.dk>
---
 meta/classes/package.bbclass | 15 ++++++++-------
 1 file changed, 8 insertions(+), 7 deletions(-)

diff --git a/meta/classes/package.bbclass b/meta/classes/package.bbclass
index 8276046369..72b9c66c3b 100644
--- a/meta/classes/package.bbclass
+++ b/meta/classes/package.bbclass
@@ -1151,21 +1151,22 @@ python populate_packages () {
 
     # Sanity check PACKAGES for duplicates
     # Sanity should be moved to sanity.bbclass once we have the infrastructure
-    package_list = []
+    package_dict = {}
 
-    for pkg in packages.split():
-        if pkg in package_list:
+    for i, pkg in enumerate(packages.split()):
+        if pkg in package_dict:
             msg = "%s is listed in PACKAGES multiple times, this leads to packaging errors." % pkg
             package_qa_handle_error("packages-list", msg, d)
         # If debug-with-srcpkg mode is enabled then the src package will have
         # priority over dbg package when assigning the files.
         # This allows src package to include source files and remove them from dbg.
         elif split_source_package and pkg.endswith("-src"):
-            package_list.insert(0, pkg)
-        elif autodebug and pkg.endswith("-dbg") and not split_source_package:
-            package_list.insert(0, pkg)
+            package_dict[pkg] = (10, i)
+        elif autodebug and pkg.endswith("-dbg"):
+            package_dict[pkg] = (30, i)
         else:
-            package_list.append(pkg)
+            package_dict[pkg] = (50, i)
+    package_list = sorted(package_dict.keys(), key=package_dict.get)
     d.setVar('PACKAGES', ' '.join(package_list))
     pkgdest = d.getVar('PKGDEST')
 
-- 
2.16.4