Merge ~larsks/cloud-init:bug/1769952 into cloud-init:master

[Lars Kellogg-Stedman]

tests: do not rely on host /proc/cmdline in test_net.py

Make test_net.TestGenerateFallbackConfig.test_unstable_names mock
the value of /proc/cmdline in the same way as the existing
test_unstable_names_disabled test.

LP: #1769952

[Server Team CI bot (server-team-bot)]

PASSED: Continuous integration, rev:fbb5c779eefe6085bd0dfd07bf2867bd3faf2f4a
https://jenkins.ubuntu.com/server/job/cloud-init-ci/1105/
Executed test runs:
    SUCCESS: Checkout
    SUCCESS: Unit & Style Tests
    SUCCESS: Ubuntu LTS: Build
    SUCCESS: Ubuntu LTS: Integration
    SUCCESS: MAAS Compatability Testing
    IN_PROGRESS: Declarative: Post Actions

Click here to trigger a rebuild:
https://jenkins.ubuntu.com/server/job/cloud-init-ci/1105/rebuild

review: Approve (continuous-integration)

[Scott Moser (smoser)]

review: Approve

[Chad Smith (chad.smith)]

An upstream commit landed for this bug.

To view that commit see the following URL:
https://git.launchpad.net/cloud-init/commit/?id=3b712fce

diff --git a/tests/unittests/test_net.py b/tests/unittests/test_net.py
index fac8267..73f26bb 100644
--- a/tests/unittests/test_net.py
+++ b/tests/unittests/test_net.py
@@ -1608,12 +1608,13 @@ iface eth1 inet dhcp
         ]
         self.assertEqual(", ".join(expected_rule) + '\n', contents.lstrip())
 
+    @mock.patch("cloudinit.util.get_cmdline")
     @mock.patch("cloudinit.util.udevadm_settle")
     @mock.patch("cloudinit.net.sys_dev_path")
     @mock.patch("cloudinit.net.read_sys_net")
     @mock.patch("cloudinit.net.get_devicelist")
     def test_unstable_names(self, mock_get_devicelist, mock_read_sys_net,
-                            mock_sys_dev_path, mock_settle):
+                            mock_sys_dev_path, mock_settle, m_get_cmdline):
         """verify that udevadm settle is called when we find unstable names"""
         devices = {
             'eth0': {
@@ -1629,6 +1630,7 @@ iface eth1 inet dhcp
 
         }
 
+        m_get_cmdline.return_value = ''
         tmp_dir = self.tmp_dir()
         _setup_test(tmp_dir, mock_get_devicelist,
                     mock_read_sys_net, mock_sys_dev_path,