Update for newer Python, Tox and Hacking

Small but overdue fix for Tox v4 support, switch to newer Hacking so
that we can test on more recent Python versions, and update the
Trove classifiers to indicate the newer jobs we're running. Also
drop Python 2.7 from the envlist since we stopped supporting it
previously, and do the same for nox for symmetry.

Remove python-dev-all from the sample bindep.txt used for testing,
since that package no longer exists on Noble.

Clean up a missed Python 2.7 workaround in setup.py as well.

Note that while we're not yet testing with Python 3.13, I ran unit
tests on it locally and everything seems to be working.

Change-Id: Ifdd15e06269b0768ef2cb6c75894dbfcdbba7a4e

.zuul.yaml

@@ -21,14 +21,9 @@
     nodeset: ubuntu-bionic
 
 - job:
-    name: bindep-ubuntu-focal
+    name: bindep-ubuntu-noble
     parent: bindep-base
-    nodeset: ubuntu-focal
-
-- job:
-    name: bindep-ubuntu-jammy
-    parent: bindep-base
-    nodeset: ubuntu-jammy
+    nodeset: ubuntu-noble
 
 - project:
     vars:
@@ -39,31 +34,25 @@
       jobs:
         - bindep-centos-9-stream
         - bindep-ubuntu-bionic
-        - bindep-ubuntu-focal
-        - bindep-ubuntu-jammy
+        - bindep-ubuntu-noble
         - build-python-release
         - nox-linters
         - nox-py36:
             nodeset: ubuntu-bionic
-        - nox-py310:
-            nodeset: ubuntu-jammy
-        - nox-py311:
-            nodeset: ubuntu-jammy
+        - nox-py312:
+            nodeset: ubuntu-noble
         - nox-cover
     gate:
       jobs:
         - bindep-centos-9-stream
         - bindep-ubuntu-bionic
-        - bindep-ubuntu-focal
-        - bindep-ubuntu-jammy
+        - bindep-ubuntu-noble
         - build-python-release
         - nox-linters
         - nox-py36:
             nodeset: ubuntu-bionic
-        - nox-py310:
-            nodeset: ubuntu-jammy
-        - nox-py311:
-            nodeset: ubuntu-jammy
+        - nox-py312:
+            nodeset: ubuntu-noble
         - nox-cover
     promote:
       jobs:

bindep/tests/bindep.txt

@@ -3,7 +3,6 @@
 
 python3-all-dev [platform:dpkg]
 python3-all [platform:dpkg]
-python-all-dev [platform:dpkg]
 python-devel [platform:rpm !platform:centos-8]
 python3-devel [platform:rpm]
 

noxfile.py

@@ -3,7 +3,7 @@ import nox
 
 nox.options.error_on_external_run = True
 nox.options.reuse_existing_virtualenvs = True
-nox.options.sessions = ["tests-3", "tests-2.7", "linters"]
+nox.options.sessions = ["tests-3", "linters"]
 
 
 # Note setting python this way seems to give us a target name without
@@ -11,7 +11,7 @@ nox.options.sessions = ["tests-3", "tests-2.7", "linters"]
 # version using --force-python.
 @nox.session(python="3")
 def linters(session):
-    session.install("hacking>=3.2.0,<3.3")
+    session.install("hacking>=7,<8")
     session.run("flake8")
 
 
@@ -36,8 +36,8 @@ def venv(session):
     session.run(*session.posargs)
 
 
-# This will attempt to run python3 and 2.7 tests by default.
-@nox.session(python=["3", "2.7"])
+# This will attempt to run python3 tests by default.
+@nox.session(python=["3"])
 def tests(session):
     session.install("-r", "requirements.txt")
     session.install("-r", "test-requirements.txt")

setup.cfg

@@ -33,6 +33,8 @@ classifier =
     Programming Language :: Python :: 3.9
     Programming Language :: Python :: 3.10
     Programming Language :: Python :: 3.11
+    Programming Language :: Python :: 3.12
+    Programming Language :: Python :: 3.13
     Programming Language :: Python :: Implementation :: CPython
     Topic :: Software Development :: Quality Assurance
     Topic :: Software Development :: Testing

setup.py

@@ -16,14 +16,6 @@
 
 import setuptools
 
-# In python < 2.7.4, a lazy loading of package `pbr` will break
-# setuptools if some other modules registered functions in `atexit`.
-# solution from: http://bugs.python.org/issue15881#msg170215
-try:
-    import multiprocessing  # noqa
-except ImportError:
-    pass
-
 setuptools.setup(
     setup_requires=['pbr'],
     pbr=True)

tox.ini

@@ -1,7 +1,6 @@
 [tox]
 min_version = 3.1
-envlist = py3,py27,pep8
-skipsdist = True
+envlist = py3,pep8
 ignore_basepython_conflict=true
 
 [testenv]
@@ -19,7 +18,7 @@ commands =
 [testenv:pep8]
 basepython = python3
 deps =
-  hacking>=3.2.0,<3.3
+  hacking>=7,<8
 commands = flake8
 
 [testenv:venv]