CI: Fix tests on Linux, Ansible tests targetting Debian 9 & 11

Without Ubuntu 20.04 virtualenv package being installed pip was installing a
version of virtualenv that couldn't create the Tox environment for Python 2.7.

> Successfully installed distlib-0.3.6 filelock-3.12.2 platformdirs-3.8.0
> pluggy-1.2.0 py-1.11.0 tomli-2.0.1 tox-3.28.0 virtualenv-20.23.1
> Finishing: Install tooling
> ...
> py27-mode_mitogen-distro_centos6 create: /home/vsts/work/1/s/.tox/py27-
> mode_mitogen-distro_centos6
> ERROR: invocation failed (exit code 1), logfile: /home/vsts/work/1/s/.tox/
> py27-mode_mitogen-distro_centos6/log/py27-mode_mitogen-distro_centos6-0.log
> ================================== log start
> ===================================
> RuntimeError: failed to query /usr/bin/python2.7 with code 1 err:
> '  File "/home/vsts/.local/lib/python3.8/site-packages/virtualenv/discovery/
> py_info.py", line 24\n    return list(OrderedDict.fromkeys(["",
> *os.environ.get("PATHEXT", "").lower().split(os.pathsep)]))\n
> ^\nSyntaxError: invalid syntax\n'

.ci/azure-pipelines-steps.yml

@@ -12,9 +12,14 @@ steps:
     versionSpec: '$(python.version)'
   condition: ne(variables['python.version'], '')
 
+- script: |
+    type python
+    python --version
+  displayName: Show python version
+
 - script: |
     sudo apt-get update
-    sudo apt-get install -y python2-dev
+    sudo apt-get install -y python2-dev python3-pip virtualenv
   displayName: Install build deps
   condition: and(eq(variables['python.version'], ''), eq(variables['Agent.OS'], 'Linux'))
 

docs/changelog.rst

@@ -28,6 +28,7 @@ v0.3.4.dev0
   resource leaks.
 * :gh:issue:`659` Removed :mod:`mitogen.compat.simplejson`, not needed with Python 2.7+, contained Python 3.x syntax errors
 * :gh:issue:`983` CI: Removed PyPI faulthandler requirement from tests
+* :gh:issue:`1001` CI: Fixed Debian 9 & 11 tests
 
 v0.3.3 (2022-06-03)
 -------------------

tests/ansible/regression/issue_776__load_plugins_called_twice.yml

@@ -15,6 +15,30 @@
       when:
         - ansible_facts.pkg_mgr in ["dnf"]
 
+    - name: Switch to archive.debian.org
+      # Debian 9 has been archived https://lists.debian.org/debian-devel-announce/2023/03/msg00006.html
+      copy:
+        content: |
+          deb http://archive.debian.org/debian stretch main contrib non-free
+        dest: /etc/apt/sources.list
+        mode: u=rw,go=r
+      when:
+        - ansible_facts.distribution == "Debian"
+        - ansible_facts.distribution_major_version == "9"
+
+    - name: Add signing keys
+      copy:
+        src: "{{ item.src }}"
+        dest: "/etc/apt/trusted.gpg.d/{{ item.src | basename }}"
+        mode: u=rw,go=r
+      loop:
+        - src: debian-archive-bullseye-automatic.gpg  # Debian 11
+        - src: debian-archive-bookworm-automatic.gpg  # Debian 12
+      when:
+        # Ideally this would check for Debian 11, but distribution_major_version
+        # is unpopulated sometimes.
+        - ansible_facts.distribution == "Debian"
+
     - name: Update package index
       apt:
         update_cache: true