zope.interface is currently rc buggy because of an unsatisfiable build-depenency on python-zope.event, the package is also orphaned.
The package is a key package, so the issue won't be dealt with by autoremovals, furthermore the python-zope.interface package has quite a stack of reverse dependencies, so dropping it doesn't seem like a good option at this point. Testing reveals that the build-dependency in question is only needed by the test suite, so I believe the least-bad option is to drop the build-dependency and not run the testsuite. It would be preferable to only disable the testsuite for python2, but I have no idea how to do that, so my current debdiff disables the testsuite completely, I also ran into an issue with the package's clean target not cleaning up properly. If anyone can suggest how to modify the package so it runs the testsuite for python3 but not python2 that would be appreciated. I plan to go ahead with an upload next week.
diff -Nru zope.interface-4.6.0/debian/changelog zope.interface-4.6.0/debian/changelog --- zope.interface-4.6.0/debian/changelog 2019-09-05 11:09:40.000000000 +0000 +++ zope.interface-4.6.0/debian/changelog 2019-12-07 07:00:43.000000000 +0000 @@ -1,3 +1,13 @@ +zope.interface (4.6.0-2) unstable; urgency=medium + + * QA upload. + * Drop build-dependency on nonexistent python-zope.event. Downgrades: #938909. + * Disable testsuite, it needs python-zope.event. + * Fix clean target. + * Add build-depends on moreutils, needed by fixed clean target. + + -- Peter Michael Green <plugw...@debian.org> Sat, 07 Dec 2019 07:00:43 +0000 + zope.interface (4.6.0-1) unstable; urgency=medium * QA upload. diff -Nru zope.interface-4.6.0/debian/control zope.interface-4.6.0/debian/control --- zope.interface-4.6.0/debian/control 2019-09-05 11:09:40.000000000 +0000 +++ zope.interface-4.6.0/debian/control 2019-12-07 07:00:43.000000000 +0000 @@ -12,11 +12,11 @@ python-all-dbg:any, python-all-dev:any, python-setuptools, - python-zope.event, python3-all-dbg:any, python3-all-dev:any, python3-setuptools, - python3-zope.event + python3-zope.event, + moreutils Standards-Version: 4.4.0 Testsuite: autopkgtest Homepage: http://pypi.python.org/pypi/zope.interface diff -Nru zope.interface-4.6.0/debian/rules zope.interface-4.6.0/debian/rules --- zope.interface-4.6.0/debian/rules 2016-07-05 21:43:11.000000000 +0000 +++ zope.interface-4.6.0/debian/rules 2019-12-07 07:00:43.000000000 +0000 @@ -97,3 +97,10 @@ override_dh_strip: dh_strip -p$(package) --dbg-package=$(package)-dbg dh_strip -p$(package3) --dbg-package=$(package3)-dbg + +override_dh_auto_test: + echo testsuite disabled + +override_dh_auto_clean: + rm -f .eggs/README.txt + rm -f src/zope.interface.egg-info/requires.txt