[FFe] colcon-core argument parsing is broken by recent changes to Python 3.11+

[Scott K Logan]

Patch version to solve a critical problem with colcon argument parsing mechanism.

 * Merge request: https://code.launchpad.net/~j-rivero/ubuntu/+source/ros2-colcon-core/+git/ros2-colcon-core/+merge/464037
 * PPA related: https://code.launchpad.net/~j-rivero/+archive/ubuntu/noble-pkgs

[Justification]

Recent changes to Python which have been backported to Python 3.11 and 3.12 break colcon argument parsing due to a dependency on private API in argparse. A fix has been released in colcon-core 0.16.1 which should be backported to any platforms which will receive the updated Python releases. The python3-colcon-core package currently in Ubuntu Noble is suffering from this issue now.

The current version in 0.15.2-1 fails to build due to problem in the test suite that detect this problem: https://code.launchpad.net/~j-rivero/+archive/ubuntu/noble-pkgs/+build/28042968

A quick test on Noble reports the problem:
--------------------- 8< ----------------------------------------
$ mkdir /tmp/colcon-repro && cd /tmp/colcon-repro
$ colcon build --cmake-args --no-warn-unused-cli

Expected:

Summary: 0 packages finished

Actual:

usage: colcon [-h] [--log-base LOG_BASE] [--log-level LOG_LEVEL] {build,extension-points,extensions,graph,info,list,metadata,test,test-result,version-check} ...
colcon: error: unrecognized arguments: --no-warn-unused-cli
--------------------- 8< ----------------------------------------

[testing done]

After using the changes proposed:

--------------------- 8< ----------------------------------------
jrivero@22d248d84027:~/code/ubuntu$ sudo dpkg -i python3-colcon-core_0.15.2-1ubuntu1_all.deb
(Reading database ... 58627 files and directories currently installed.)
Preparing to unpack python3-colcon-core_0.15.2-1ubuntu1_all.deb ...
Unpacking python3-colcon-core (0.15.2-1ubuntu1) over (0.15.2-1) ...
Setting up python3-colcon-core (0.15.2-1ubuntu1) ...
jrivero@22d248d84027:/tmp/colcon-repro$ colcon build --cmake-args --no-warn-unused-cli

Summary: 0 packages finished [0.28s]
--------------------- 8< ----------------------------------------

Playing with other colcon workspaces does not show any problem to
my eyes when passing different cmake-args like modifying the CMAKE_BUILD_TYPE.

[Original Scott email]
--- 8< ---------------------------

Recent changes to Python which have been backported to Python 3.11 and 3.12 break colcon argument parsing due to a dependency on private API in argparse.

A fix has been released in colcon-core 0.16.1 which should be backported to any platforms which will receive the updated Python releases.

The python3-colcon-core package currently in Ubuntu Noble is suffering from this issue now.

https://github.com/colcon/colcon-core/pull/635

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Ubuntu Foundations Team Bug Bot (crichton)]

The attachment "0001-Fix-argument-parsing-in-newer-Python.patch" seems to be a patch. If it isn't, please remove the "patch" flag from the attachment, remove the "patch" tag, and if you are a member of the ~ubuntu-reviewers, unsubscribe the team.

[This is an automated message performed by a Launchpad user owned by ~brian-murray, for any issues please contact him.]

[Jose Luis Rivero (j-rivero)]

In coordination with Scott, we have raised this to be a FFe since the package is severity damaged as it is now and probably unusable for any use case that is not completely trivial.

I've created and linked the merge-request with the bumped version against ubuntu/devel and testing the package.

[Benjamin Drung (bdrung)]

Sponsored since this is just a bug fix and not a new feature.

[Launchpad Janitor (janitor)]

This bug was fixed in the package ros2-colcon-core - 0.15.2-1ubuntu1

---------------
ros2-colcon-core (0.15.2-1ubuntu1) noble; urgency=medium

  * Add patch to fix argument parsing with Python 3.12
    (LP: #2060717)

 -- Jose Luis Rivero <email address hidden> Tue, 09 Apr 2024 20:51:44 +0200