Migrate off SafeConfigParser

[luca-della-vedova]

SafeConfigParser has been deprecated since Python 3.2. There has been a shim which has been finally removed in Python 3.11 in this commit in favor of simply ConfigParser.

This means that this utility won't work if users are on Python >= 3.11 (which is the case for Ubuntu Noble).
In this PR I migrated to ConfigParser and took the liberty to remove the try except that made the package work for Python 2 since Python 2 is been EOL for more than 4 years now (this fix would have been more boilerplate otherwise).

readfp was also deprecated in favor of read_file.

Test it!

Try building a package on Ubuntu 22.04, then try on Ubuntu 24.04. For example, when
trying to build colcon-cmake using the publish-python utility, the output under Ubuntu 24.04 is:

~/colcon-cmake$ ../publish-python/bin/publish-python 
[CUT]
== Creating 'stdeb' artifacts ...

-- Building sdist_dsc and bdist_deb package ...
$ /usr/bin/python3 setup.py --command-packages=stdeb.command sdist_dsc --source python3-colcon-cmake --with-python3 true --with-python2 false --force-x-python3-version bdist_deb 
running sdist_dsc
running egg_info
writing colcon_cmake.egg-info/PKG-INFO
writing dependency_links to colcon_cmake.egg-info/dependency_links.txt
writing entry points to colcon_cmake.egg-info/entry_points.txt
writing requirements to colcon_cmake.egg-info/requires.txt
writing top-level names to colcon_cmake.egg-info/top_level.txt
reading manifest file 'colcon_cmake.egg-info/SOURCES.txt'
adding license file 'LICENSE'
writing manifest file 'colcon_cmake.egg-info/SOURCES.txt'
Traceback (most recent call last):
  File "/home/lucadv/colcon-cmake/setup.py", line 6, in <module>
    setup()
  File "/usr/lib/python3/dist-packages/setuptools/__init__.py", line 107, in setup
    return distutils.core.setup(**attrs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3/dist-packages/setuptools/_distutils/core.py", line 185, in setup
    return run_commands(dist)
           ^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3/dist-packages/setuptools/_distutils/core.py", line 201, in run_commands
    dist.run_commands()
  File "/usr/lib/python3/dist-packages/setuptools/_distutils/dist.py", line 969, in run_commands
    self.run_command(cmd)
  File "/usr/lib/python3/dist-packages/setuptools/dist.py", line 1233, in run_command
    super().run_command(command)
  File "/usr/lib/python3/dist-packages/setuptools/_distutils/dist.py", line 988, in run_command
    cmd_obj.run()
  File "/usr/lib/python3/dist-packages/stdeb/command/sdist_dsc.py", line 30, in run
    debinfo = self.get_debinfo()
              ^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3/dist-packages/stdeb/command/common.py", line 197, in get_debinfo
    debinfo = DebianInfo(
              ^^^^^^^^^^^
  File "/usr/lib/python3/dist-packages/stdeb/util.py", line 802, in __init__
    check_cfg_files(cfg_files, module_name)
  File "/usr/lib/python3/dist-packages/stdeb/util.py", line 733, in check_cfg_files
    cfg = ConfigParser.SafeConfigParser()
          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
AttributeError: module 'configparser' has no attribute 'SafeConfigParser'. Did you mean: 'RawConfigParser'?
Traceback (most recent call last):
  File "/home/lucadv/colcon-cmake/../publish-python/bin/publish-python", line 24, in <module>
    rc = main()
         ^^^^^^
  File "/home/lucadv/publish-python/publish_python/cli.py", line 77, in main
    artifacts = artifact_handlers[artifact_type](config=artifact.config)
                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/lucadv/publish-python/publish_python/artifact/stdeb.py", line 44, in create_deb
    subprocess.check_call(cmd, env=dict(os.environ, **add_env))
  File "/usr/lib/python3.12/subprocess.py", line 413, in check_call
    raise CalledProcessError(retcode, cmd)
subprocess.CalledProcessError: Command '['/usr/bin/python3', 'setup.py', '--command-packages=stdeb.command', 'sdist_dsc', '--source', 'python3-colcon-cmake', '--with-python3', 'true', '--with-python2', 'false', '--force-x-python3-version', 'bdist_deb']' returned non-zero exit status 1.

Now try the PR code:

• sudo apt remove python3-stdeb.
• pip install git+https://github.com/luca-della-vedova/stdeb@luca/migrate_configparser --break-system-packages
• rebuild the package
• It works!

[luca-della-vedova]

@nuclearsandwich @cottsay As people adopt distros with Python >= 3.11 this will become increasingly more common (i.e. #197 that was just opened), can you take a look? The main "controversial" part is that in its current form the change would drop Python 2 compatibility (which imho is OK, but I'm happy to put the extra work to keep it if it's needed)

[ampledata]

@nuclearsandwich @cottsay As people adopt distros with Python >= 3.11 this will become increasingly more common (i.e. #197 that was just opened), can you take a look? The main "controversial" part is that in its current form the change would drop Python 2 compatibility (which imho is OK, but I'm happy to put the extra work to keep it if it's needed)

[nuclearsandwich]

Thanks @luca-della-vedova

I'm not going to merge this right away because I want to include it in a more formal dropping of Python 2 support.