Invalid version string {debupstream:packaging} with nest-part

[Adam Reviczky]

Using git recipe format 0.4 with {debupstream:packaging} of a nest-part which has debian/changelog in the branch gives an error:

HEAD is now at 991bf4ef7 2023.08.27 13:30
From https://git.launchpad.net/~reviczky/+git/context-debian
 * [new branch] master -> source-packaging/master
Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/gitbuildrecipe/deb_util.py", line 155, in add_autobuild_changelog_entry
    changelog.Version(version)
  File "/usr/lib/python3/dist-packages/debian/debian_support.py", line 250, in __init__
    super(AptPkgVersion, self).__init__(version)
  File "/usr/lib/python3/dist-packages/debian/debian_support.py", line 133, in __init__
    self.full_version = version
  File "/usr/lib/python3/dist-packages/debian/debian_support.py", line 162, in __setattr__
    self._set_full_version(str(value))
  File "/usr/lib/python3/dist-packages/debian/debian_support.py", line 139, in _set_full_version
    raise ValueError("Invalid version string %r" % version)
ValueError: Invalid version string '{debupstream:packaging}.20230827+dfsg-1~ubuntu23.10.1'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/bin/git-build-recipe", line 11, in <module>
    load_entry_point('git-build-recipe==0.1', 'console_scripts', 'git-build-recipe')()
  File "/usr/lib/python3/dist-packages/gitbuildrecipe/main.py", line 144, in main
    add_autobuild_changelog_entry(
  File "/usr/lib/python3/dist-packages/gitbuildrecipe/deb_util.py", line 157, in add_autobuild_changelog_entry
    raise Exception("Invalid deb-version: %s: %s" % (version, e))
Exception: Invalid deb-version: {debupstream:packaging}.20230827+dfsg-1~ubuntu23.10.1: Invalid version string '{debupstream:packaging}.20230827+dfsg-1~ubuntu23.10.1'
RUN: /usr/share/launchpad-buildd/bin/in-target scan-for-processes --backend=chroot --series=mantic --arch=amd64 RECIPEBRANCHBUILD-3594804
Scanning for processes to kill in build RECIPEBRANCHBUILD-3594804

Launchpad recipe used:
# git-build-recipe format 0.4 deb-version {debupstream:packaging}.{date}+dfsg-1
lp:~reviczky/+git/context-texlive
nest texmf-dist lp:~reviczky/context/+git/master texmf-dist main
nest-part packaging lp:~reviczky/+git/context-debian debian debian master

Full log: https://launchpadlibrarian.net/683948138/buildlog.txt.gz

[Colin Watson (cjwatson)]

I believe https://paste.ubuntu.com/p/R9p8SFQsyK/ will fix this, but we need to work out why we missed this before and how to unit-test it properly.