Reorganize unit test locations under tests/unittests (#1126)

This attempts to standardize unit test file location under test/unittests/
such that any source file located at cloudinit/path/to/file.py may have a
corresponding unit test file at test/unittests/path/to/test_file.py.

Noteworthy Comments:
====================
Four different duplicate test files existed:
test_{gpg,util,cc_mounts,cc_resolv_conf}.py
Each of these duplicate file pairs has been merged together. This is a
break in git history for these files.

The test suite appears to have a dependency on test order. Changing test
order causes some tests to fail. This should be rectified, but for now
some tests have been modified in
tests/unittests/config/test_set_passwords.py.

A helper class name starts with "Test" which causes pytest to try
executing it as a test case, which then throws warnings "due to Class
having __init__()".  Silence by changing the name of the class.

# helpers.py is imported in many test files, import paths change
cloudinit/tests/helpers.py -> tests/unittests/helpers.py

# Move directories:
cloudinit/distros/tests -> tests/unittests/distros
cloudinit/cmd/devel/tests -> tests/unittests/cmd/devel
cloudinit/cmd/tests -> tests/unittests/cmd/
cloudinit/sources/helpers/tests -> tests/unittests/sources/helpers
cloudinit/sources/tests -> tests/unittests/sources
cloudinit/net/tests -> tests/unittests/net
cloudinit/config/tests -> tests/unittests/config
cloudinit/analyze/tests/ -> tests/unittests/analyze/

# Standardize tests already in tests/unittests/
test_datasource -> sources
test_distros -> distros
test_vmware -> sources/vmware
test_handler -> config        # this contains cloudconfig module tests
test_runs -> runs

1 files changed, 564 insertions, 0 deletions

diff --git a/tests/unittests/config/test_cc_snap.py b/tests/unittests/config/test_cc_snap.py
new file mode 100644
index 00000000..e8113eca
--- /dev/null
+++ b/tests/unittests/config/test_cc_snap.py
@@ -0,0 +1,564 @@
+# This file is part of cloud-init. See LICENSE file for license information.
+
+import re
+from io import StringIO
+
+from cloudinit.config.cc_snap import (
+    ASSERTIONS_FILE, add_assertions, handle, maybe_install_squashfuse,
+    run_commands, schema)
+from cloudinit.config.schema import validate_cloudconfig_schema
+from cloudinit import util
+from tests.unittests.helpers import (
+    CiTestCase, SchemaTestCaseMixin, mock, wrap_and_call, skipUnlessJsonSchema)
+
+
+SYSTEM_USER_ASSERTION = """\
+type: system-user
+authority-id: LqvZQdfyfGlYvtep4W6Oj6pFXP9t1Ksp
+brand-id: LqvZQdfyfGlYvtep4W6Oj6pFXP9t1Ksp
+email: foo@bar.com
+password: $6$E5YiAuMIPAwX58jG$miomhVNui/vf7f/3ctB/f0RWSKFxG0YXzrJ9rtJ1ikvzt
+series:
+- 16
+since: 2016-09-10T16:34:00+03:00
+until: 2017-11-10T16:34:00+03:00
+username: baz
+sign-key-sha3-384: RuVvnp4n52GilycjfbbTCI3_L8Y6QlIE75wxMc0KzGV3AUQqVd9GuXoj
+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"""
+
+ACCOUNT_ASSERTION = """\
+type: account-key
+authority-id: canonical
+revision: 2
+public-key-sha3-384: BWDEoaqyr25nF5SNCvEv2v7QnM9QsfCc0PBMYD_i2NGSQ32EF2d4D0
+account-id: canonical
+name: store
+since: 2016-04-01T00:00:00.0Z
+body-length: 717
+sign-key-sha3-384: -CvQKAwRQ5h3Ffn10FILJoEZUXOv6km9FwA80-Rcj-f-6jadQ89VRswH
+
+AcbBTQRWhcGAARAA0KKYYQWuHOrsFVi4p4l7ZzSvX7kLgJFFeFgOkzdWKBTHEnsMKjl5mefFe9j
+qe8NlmJdfY7BenP7XeBtwKp700H/t9lLrZbpTNAPHXYxEWFJp5bPqIcJYBZ+29oLVLN1Tc5X482
+vCiDqL8+pPYqBrK2fNlyPlNNSum9wI70rDDL4r6FVvr+osTnGejibdV8JphWX+lrSQDnRSdM8KJ
+UM43vTgLGTi9W54oRhsA2OFexRfRksTrnqGoonCjqX5wO3OFSaMDzMsO2MJ/hPfLgDqw53qjzuK
+Iec9OL3k5basvu2cj5u9tKwVFDsCKK2GbKUsWWpx2KTpOifmhmiAbzkTHbH9KaoMS7p0kJwhTQG
+o9aJ9VMTWHJc/NCBx7eu451u6d46sBPCXS/OMUh2766fQmoRtO1OwCTxsRKG2kkjbMn54UdFULl
+VfzvyghMNRKIezsEkmM8wueTqGUGZWa6CEZqZKwhe/PROxOPYzqtDH18XZknbU1n5lNb7vNfem9
+2ai+3+JyFnW9UhfvpVF7gzAgdyCqNli4C6BIN43uwoS8HkykocZS/+Gv52aUQ/NZ8BKOHLw+7an
+Q0o8W9ltSLZbEMxFIPSN0stiZlkXAp6DLyvh1Y4wXSynDjUondTpej2fSvSlCz/W5v5V7qA4nIc
+vUvV7RjVzv17ut0AEQEAAQ==
+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"""
+
+
+class FakeCloud(object):
+    def __init__(self, distro):
+        self.distro = distro
+
+
+class TestAddAssertions(CiTestCase):
+
+    with_logs = True
+
+    def setUp(self):
+        super(TestAddAssertions, self).setUp()
+        self.tmp = self.tmp_dir()
+
+    @mock.patch('cloudinit.config.cc_snap.subp.subp')
+    def test_add_assertions_on_empty_list(self, m_subp):
+        """When provided with an empty list, add_assertions does nothing."""
+        add_assertions([])
+        self.assertEqual('', self.logs.getvalue())
+        m_subp.assert_not_called()
+
+    def test_add_assertions_on_non_list_or_dict(self):
+        """When provided an invalid type, add_assertions raises an error."""
+        with self.assertRaises(TypeError) as context_manager:
+            add_assertions(assertions="I'm Not Valid")
+        self.assertEqual(
+            "assertion parameter was not a list or dict: I'm Not Valid",
+            str(context_manager.exception))
+
+    @mock.patch('cloudinit.config.cc_snap.subp.subp')
+    def test_add_assertions_adds_assertions_as_list(self, m_subp):
+        """When provided with a list, add_assertions adds all assertions."""
+        self.assertEqual(
+            ASSERTIONS_FILE, '/var/lib/cloud/instance/snapd.assertions')
+        assert_file = self.tmp_path('snapd.assertions', dir=self.tmp)
+        assertions = [SYSTEM_USER_ASSERTION, ACCOUNT_ASSERTION]
+        wrap_and_call(
+            'cloudinit.config.cc_snap',
+            {'ASSERTIONS_FILE': {'new': assert_file}},
+            add_assertions, assertions)
+        self.assertIn(
+            'Importing user-provided snap assertions', self.logs.getvalue())
+        self.assertIn(
+            'sertions', self.logs.getvalue())
+        self.assertEqual(
+            [mock.call(['snap', 'ack', assert_file], capture=True)],
+            m_subp.call_args_list)
+        compare_file = self.tmp_path('comparison', dir=self.tmp)
+        util.write_file(compare_file, '\n'.join(assertions).encode('utf-8'))
+        self.assertEqual(
+            util.load_file(compare_file), util.load_file(assert_file))
+
+    @mock.patch('cloudinit.config.cc_snap.subp.subp')
+    def test_add_assertions_adds_assertions_as_dict(self, m_subp):
+        """When provided with a dict, add_assertions adds all assertions."""
+        self.assertEqual(
+            ASSERTIONS_FILE, '/var/lib/cloud/instance/snapd.assertions')
+        assert_file = self.tmp_path('snapd.assertions', dir=self.tmp)
+        assertions = {'00': SYSTEM_USER_ASSERTION, '01': ACCOUNT_ASSERTION}
+        wrap_and_call(
+            'cloudinit.config.cc_snap',
+            {'ASSERTIONS_FILE': {'new': assert_file}},
+            add_assertions, assertions)
+        self.assertIn(
+            'Importing user-provided snap assertions', self.logs.getvalue())
+        self.assertIn(
+            "DEBUG: Snap acking: ['type: system-user', 'authority-id: Lqv",
+            self.logs.getvalue())
+        self.assertIn(
+            "DEBUG: Snap acking: ['type: account-key', 'authority-id: canonic",
+            self.logs.getvalue())
+        self.assertEqual(
+            [mock.call(['snap', 'ack', assert_file], capture=True)],
+            m_subp.call_args_list)
+        compare_file = self.tmp_path('comparison', dir=self.tmp)
+        combined = '\n'.join(assertions.values())
+        util.write_file(compare_file, combined.encode('utf-8'))
+        self.assertEqual(
+            util.load_file(compare_file), util.load_file(assert_file))
+
+
+class TestRunCommands(CiTestCase):
+
+    with_logs = True
+    allowed_subp = [CiTestCase.SUBP_SHELL_TRUE]
+
+    def setUp(self):
+        super(TestRunCommands, self).setUp()
+        self.tmp = self.tmp_dir()
+
+    @mock.patch('cloudinit.config.cc_snap.subp.subp')
+    def test_run_commands_on_empty_list(self, m_subp):
+        """When provided with an empty list, run_commands does nothing."""
+        run_commands([])
+        self.assertEqual('', self.logs.getvalue())
+        m_subp.assert_not_called()
+
+    def test_run_commands_on_non_list_or_dict(self):
+        """When provided an invalid type, run_commands raises an error."""
+        with self.assertRaises(TypeError) as context_manager:
+            run_commands(commands="I'm Not Valid")
+        self.assertEqual(
+            "commands parameter was not a list or dict: I'm Not Valid",
+            str(context_manager.exception))
+
+    def test_run_command_logs_commands_and_exit_codes_to_stderr(self):
+        """All exit codes are logged to stderr."""
+        outfile = self.tmp_path('output.log', dir=self.tmp)
+
+        cmd1 = 'echo "HI" >> %s' % outfile
+        cmd2 = 'bogus command'
+        cmd3 = 'echo "MOM" >> %s' % outfile
+        commands = [cmd1, cmd2, cmd3]
+
+        mock_path = 'cloudinit.config.cc_snap.sys.stderr'
+        with mock.patch(mock_path, new_callable=StringIO) as m_stderr:
+            with self.assertRaises(RuntimeError) as context_manager:
+                run_commands(commands=commands)
+
+        self.assertIsNotNone(
+            re.search(r'bogus: (command )?not found',
+                      str(context_manager.exception)),
+            msg='Expected bogus command not found')
+        expected_stderr_log = '\n'.join([
+            'Begin run command: {cmd}'.format(cmd=cmd1),
+            'End run command: exit(0)',
+            'Begin run command: {cmd}'.format(cmd=cmd2),
+            'ERROR: End run command: exit(127)',
+            'Begin run command: {cmd}'.format(cmd=cmd3),
+            'End run command: exit(0)\n'])
+        self.assertEqual(expected_stderr_log, m_stderr.getvalue())
+
+    def test_run_command_as_lists(self):
+        """When commands are specified as a list, run them in order."""
+        outfile = self.tmp_path('output.log', dir=self.tmp)
+
+        cmd1 = 'echo "HI" >> %s' % outfile
+        cmd2 = 'echo "MOM" >> %s' % outfile
+        commands = [cmd1, cmd2]
+        mock_path = 'cloudinit.config.cc_snap.sys.stderr'
+        with mock.patch(mock_path, new_callable=StringIO):
+            run_commands(commands=commands)
+
+        self.assertIn(
+            'DEBUG: Running user-provided snap commands',
+            self.logs.getvalue())
+        self.assertEqual('HI\nMOM\n', util.load_file(outfile))
+        self.assertIn(
+            'WARNING: Non-snap commands in snap config:', self.logs.getvalue())
+
+    def test_run_command_dict_sorted_as_command_script(self):
+        """When commands are a dict, sort them and run."""
+        outfile = self.tmp_path('output.log', dir=self.tmp)
+        cmd1 = 'echo "HI" >> %s' % outfile
+        cmd2 = 'echo "MOM" >> %s' % outfile
+        commands = {'02': cmd1, '01': cmd2}
+        mock_path = 'cloudinit.config.cc_snap.sys.stderr'
+        with mock.patch(mock_path, new_callable=StringIO):
+            run_commands(commands=commands)
+
+        expected_messages = [
+            'DEBUG: Running user-provided snap commands']
+        for message in expected_messages:
+            self.assertIn(message, self.logs.getvalue())
+        self.assertEqual('MOM\nHI\n', util.load_file(outfile))
+
+
+@skipUnlessJsonSchema()
+class TestSchema(CiTestCase, SchemaTestCaseMixin):
+
+    with_logs = True
+    schema = schema
+
+    def test_schema_warns_on_snap_not_as_dict(self):
+        """If the snap configuration is not a dict, emit a warning."""
+        validate_cloudconfig_schema({'snap': 'wrong type'}, schema)
+        self.assertEqual(
+            "WARNING: Invalid config:\nsnap: 'wrong type' is not of type"
+            " 'object'\n",
+            self.logs.getvalue())
+
+    @mock.patch('cloudinit.config.cc_snap.run_commands')
+    def test_schema_disallows_unknown_keys(self, _):
+        """Unknown keys in the snap configuration emit warnings."""
+        validate_cloudconfig_schema(
+            {'snap': {'commands': ['ls'], 'invalid-key': ''}}, schema)
+        self.assertIn(
+            'WARNING: Invalid config:\nsnap: Additional properties are not'
+            " allowed ('invalid-key' was unexpected)",
+            self.logs.getvalue())
+
+    def test_warn_schema_requires_either_commands_or_assertions(self):
+        """Warn when snap configuration lacks both commands and assertions."""
+        validate_cloudconfig_schema(
+            {'snap': {}}, schema)
+        self.assertIn(
+            'WARNING: Invalid config:\nsnap: {} does not have enough'
+            ' properties',
+            self.logs.getvalue())
+
+    @mock.patch('cloudinit.config.cc_snap.run_commands')
+    def test_warn_schema_commands_is_not_list_or_dict(self, _):
+        """Warn when snap:commands config is not a list or dict."""
+        validate_cloudconfig_schema(
+            {'snap': {'commands': 'broken'}}, schema)
+        self.assertEqual(
+            "WARNING: Invalid config:\nsnap.commands: 'broken' is not of type"
+            " 'object', 'array'\n",
+            self.logs.getvalue())
+
+    @mock.patch('cloudinit.config.cc_snap.run_commands')
+    def test_warn_schema_when_commands_is_empty(self, _):
+        """Emit warnings when snap:commands is an empty list or dict."""
+        validate_cloudconfig_schema(
+            {'snap': {'commands': []}}, schema)
+        validate_cloudconfig_schema(
+            {'snap': {'commands': {}}}, schema)
+        self.assertEqual(
+            "WARNING: Invalid config:\nsnap.commands: [] is too short\n"
+            "WARNING: Invalid config:\nsnap.commands: {} does not have enough"
+            " properties\n",
+            self.logs.getvalue())
+
+    @mock.patch('cloudinit.config.cc_snap.run_commands')
+    def test_schema_when_commands_are_list_or_dict(self, _):
+        """No warnings when snap:commands are either a list or dict."""
+        validate_cloudconfig_schema(
+            {'snap': {'commands': ['valid']}}, schema)
+        validate_cloudconfig_schema(
+            {'snap': {'commands': {'01': 'also valid'}}}, schema)
+        self.assertEqual('', self.logs.getvalue())
+
+    @mock.patch('cloudinit.config.cc_snap.run_commands')
+    def test_schema_when_commands_values_are_invalid_type(self, _):
+        """Warnings when snap:commands values are invalid type (e.g. int)"""
+        validate_cloudconfig_schema(
+            {'snap': {'commands': [123]}}, schema)
+        validate_cloudconfig_schema(
+            {'snap': {'commands': {'01': 123}}}, schema)
+        self.assertEqual(
+            "WARNING: Invalid config:\n"
+            "snap.commands.0: 123 is not valid under any of the given"
+            " schemas\n"
+            "WARNING: Invalid config:\n"
+            "snap.commands.01: 123 is not valid under any of the given"
+            " schemas\n",
+            self.logs.getvalue())
+
+    @mock.patch('cloudinit.config.cc_snap.run_commands')
+    def test_schema_when_commands_list_values_are_invalid_type(self, _):
+        """Warnings when snap:commands list values are wrong type (e.g. int)"""
+        validate_cloudconfig_schema(
+            {'snap': {'commands': [["snap", "install", 123]]}}, schema)
+        validate_cloudconfig_schema(
+            {'snap': {'commands': {'01': ["snap", "install", 123]}}}, schema)
+        self.assertEqual(
+            "WARNING: Invalid config:\n"
+            "snap.commands.0: ['snap', 'install', 123] is not valid under any"
+            " of the given schemas\n",
+            "WARNING: Invalid config:\n"
+            "snap.commands.0: ['snap', 'install', 123] is not valid under any"
+            " of the given schemas\n",
+            self.logs.getvalue())
+
+    @mock.patch('cloudinit.config.cc_snap.run_commands')
+    def test_schema_when_assertions_values_are_invalid_type(self, _):
+        """Warnings when snap:assertions values are invalid type (e.g. int)"""
+        validate_cloudconfig_schema(
+            {'snap': {'assertions': [123]}}, schema)
+        validate_cloudconfig_schema(
+            {'snap': {'assertions': {'01': 123}}}, schema)
+        self.assertEqual(
+            "WARNING: Invalid config:\n"
+            "snap.assertions.0: 123 is not of type 'string'\n"
+            "WARNING: Invalid config:\n"
+            "snap.assertions.01: 123 is not of type 'string'\n",
+            self.logs.getvalue())
+
+    @mock.patch('cloudinit.config.cc_snap.add_assertions')
+    def test_warn_schema_assertions_is_not_list_or_dict(self, _):
+        """Warn when snap:assertions config is not a list or dict."""
+        validate_cloudconfig_schema(
+            {'snap': {'assertions': 'broken'}}, schema)
+        self.assertEqual(
+            "WARNING: Invalid config:\nsnap.assertions: 'broken' is not of"
+            " type 'object', 'array'\n",
+            self.logs.getvalue())
+
+    @mock.patch('cloudinit.config.cc_snap.add_assertions')
+    def test_warn_schema_when_assertions_is_empty(self, _):
+        """Emit warnings when snap:assertions is an empty list or dict."""
+        validate_cloudconfig_schema(
+            {'snap': {'assertions': []}}, schema)
+        validate_cloudconfig_schema(
+            {'snap': {'assertions': {}}}, schema)
+        self.assertEqual(
+            "WARNING: Invalid config:\nsnap.assertions: [] is too short\n"
+            "WARNING: Invalid config:\nsnap.assertions: {} does not have"
+            " enough properties\n",
+            self.logs.getvalue())
+
+    @mock.patch('cloudinit.config.cc_snap.add_assertions')
+    def test_schema_when_assertions_are_list_or_dict(self, _):
+        """No warnings when snap:assertions are a list or dict."""
+        validate_cloudconfig_schema(
+            {'snap': {'assertions': ['valid']}}, schema)
+        validate_cloudconfig_schema(
+            {'snap': {'assertions': {'01': 'also valid'}}}, schema)
+        self.assertEqual('', self.logs.getvalue())
+
+    def test_duplicates_are_fine_array_array(self):
+        """Duplicated commands array/array entries are allowed."""
+        self.assertSchemaValid(
+            {'commands': [["echo", "bye"], ["echo", "bye"]]},
+            "command entries can be duplicate.")
+
+    def test_duplicates_are_fine_array_string(self):
+        """Duplicated commands array/string entries are allowed."""
+        self.assertSchemaValid(
+            {'commands': ["echo bye", "echo bye"]},
+            "command entries can be duplicate.")
+
+    def test_duplicates_are_fine_dict_array(self):
+        """Duplicated commands dict/array entries are allowed."""
+        self.assertSchemaValid(
+            {'commands': {'00': ["echo", "bye"], '01': ["echo", "bye"]}},
+            "command entries can be duplicate.")
+
+    def test_duplicates_are_fine_dict_string(self):
+        """Duplicated commands dict/string entries are allowed."""
+        self.assertSchemaValid(
+            {'commands': {'00': "echo bye", '01': "echo bye"}},
+            "command entries can be duplicate.")
+
+
+class TestHandle(CiTestCase):
+
+    with_logs = True
+
+    def setUp(self):
+        super(TestHandle, self).setUp()
+        self.tmp = self.tmp_dir()
+
+    @mock.patch('cloudinit.config.cc_snap.run_commands')
+    @mock.patch('cloudinit.config.cc_snap.add_assertions')
+    @mock.patch('cloudinit.config.cc_snap.validate_cloudconfig_schema')
+    def test_handle_no_config(self, m_schema, m_add, m_run):
+        """When no snap-related configuration is provided, nothing happens."""
+        cfg = {}
+        handle('snap', cfg=cfg, cloud=None, log=self.logger, args=None)
+        self.assertIn(
+            "DEBUG: Skipping module named snap, no 'snap' key in config",
+            self.logs.getvalue())
+        m_schema.assert_not_called()
+        m_add.assert_not_called()
+        m_run.assert_not_called()
+
+    @mock.patch('cloudinit.config.cc_snap.run_commands')
+    @mock.patch('cloudinit.config.cc_snap.add_assertions')
+    @mock.patch('cloudinit.config.cc_snap.maybe_install_squashfuse')
+    def test_handle_skips_squashfuse_when_unconfigured(self, m_squash, m_add,
+                                                       m_run):
+        """When squashfuse_in_container is unset, don't attempt to install."""
+        handle(
+            'snap', cfg={'snap': {}}, cloud=None, log=self.logger, args=None)
+        handle(
+            'snap', cfg={'snap': {'squashfuse_in_container': None}},
+            cloud=None, log=self.logger, args=None)
+        handle(
+            'snap', cfg={'snap': {'squashfuse_in_container': False}},
+            cloud=None, log=self.logger, args=None)
+        self.assertEqual([], m_squash.call_args_list)  # No calls
+        # snap configuration missing assertions and commands will default to []
+        self.assertIn(mock.call([]), m_add.call_args_list)
+        self.assertIn(mock.call([]), m_run.call_args_list)
+
+    @mock.patch('cloudinit.config.cc_snap.maybe_install_squashfuse')
+    def test_handle_tries_to_install_squashfuse(self, m_squash):
+        """If squashfuse_in_container is True, try installing squashfuse."""
+        cfg = {'snap': {'squashfuse_in_container': True}}
+        mycloud = FakeCloud(None)
+        handle('snap', cfg=cfg, cloud=mycloud, log=self.logger, args=None)
+        self.assertEqual(
+            [mock.call(mycloud)], m_squash.call_args_list)
+
+    def test_handle_runs_commands_provided(self):
+        """If commands are specified as a list, run them."""
+        outfile = self.tmp_path('output.log', dir=self.tmp)
+
+        cfg = {
+            'snap': {'commands': ['echo "HI" >> %s' % outfile,
+                                  'echo "MOM" >> %s' % outfile]}}
+        mock_path = 'cloudinit.config.cc_snap.sys.stderr'
+        with self.allow_subp([CiTestCase.SUBP_SHELL_TRUE]):
+            with mock.patch(mock_path, new_callable=StringIO):
+                handle('snap', cfg=cfg, cloud=None, log=self.logger, args=None)
+
+        self.assertEqual('HI\nMOM\n', util.load_file(outfile))
+
+    @mock.patch('cloudinit.config.cc_snap.subp.subp')
+    def test_handle_adds_assertions(self, m_subp):
+        """Any configured snap assertions are provided to add_assertions."""
+        assert_file = self.tmp_path('snapd.assertions', dir=self.tmp)
+        compare_file = self.tmp_path('comparison', dir=self.tmp)
+        cfg = {
+            'snap': {'assertions': [SYSTEM_USER_ASSERTION, ACCOUNT_ASSERTION]}}
+        wrap_and_call(
+            'cloudinit.config.cc_snap',
+            {'ASSERTIONS_FILE': {'new': assert_file}},
+            handle, 'snap', cfg=cfg, cloud=None, log=self.logger, args=None)
+        content = '\n'.join(cfg['snap']['assertions'])
+        util.write_file(compare_file, content.encode('utf-8'))
+        self.assertEqual(
+            util.load_file(compare_file), util.load_file(assert_file))
+
+    @mock.patch('cloudinit.config.cc_snap.subp.subp')
+    @skipUnlessJsonSchema()
+    def test_handle_validates_schema(self, m_subp):
+        """Any provided configuration is runs validate_cloudconfig_schema."""
+        assert_file = self.tmp_path('snapd.assertions', dir=self.tmp)
+        cfg = {'snap': {'invalid': ''}}  # Generates schema warning
+        wrap_and_call(
+            'cloudinit.config.cc_snap',
+            {'ASSERTIONS_FILE': {'new': assert_file}},
+            handle, 'snap', cfg=cfg, cloud=None, log=self.logger, args=None)
+        self.assertEqual(
+            "WARNING: Invalid config:\nsnap: Additional properties are not"
+            " allowed ('invalid' was unexpected)\n",
+            self.logs.getvalue())
+
+
+class TestMaybeInstallSquashFuse(CiTestCase):
+
+    with_logs = True
+
+    def setUp(self):
+        super(TestMaybeInstallSquashFuse, self).setUp()
+        self.tmp = self.tmp_dir()
+
+    @mock.patch('cloudinit.config.cc_snap.util.is_container')
+    def test_maybe_install_squashfuse_skips_non_containers(self, m_container):
+        """maybe_install_squashfuse does nothing when not on a container."""
+        m_container.return_value = False
+        maybe_install_squashfuse(cloud=FakeCloud(None))
+        self.assertEqual([mock.call()], m_container.call_args_list)
+        self.assertEqual('', self.logs.getvalue())
+
+    @mock.patch('cloudinit.config.cc_snap.util.is_container')
+    def test_maybe_install_squashfuse_raises_install_errors(self, m_container):
+        """maybe_install_squashfuse logs and raises package install errors."""
+        m_container.return_value = True
+        distro = mock.MagicMock()
+        distro.update_package_sources.side_effect = RuntimeError(
+            'Some apt error')
+        with self.assertRaises(RuntimeError) as context_manager:
+            maybe_install_squashfuse(cloud=FakeCloud(distro))
+        self.assertEqual('Some apt error', str(context_manager.exception))
+        self.assertIn('Package update failed\nTraceback', self.logs.getvalue())
+
+    @mock.patch('cloudinit.config.cc_snap.util.is_container')
+    def test_maybe_install_squashfuse_raises_update_errors(self, m_container):
+        """maybe_install_squashfuse logs and raises package update errors."""
+        m_container.return_value = True
+        distro = mock.MagicMock()
+        distro.update_package_sources.side_effect = RuntimeError(
+            'Some apt error')
+        with self.assertRaises(RuntimeError) as context_manager:
+            maybe_install_squashfuse(cloud=FakeCloud(distro))
+        self.assertEqual('Some apt error', str(context_manager.exception))
+        self.assertIn('Package update failed\nTraceback', self.logs.getvalue())
+
+    @mock.patch('cloudinit.config.cc_snap.util.is_container')
+    def test_maybe_install_squashfuse_happy_path(self, m_container):
+        """maybe_install_squashfuse logs and raises package install errors."""
+        m_container.return_value = True
+        distro = mock.MagicMock()  # No errors raised
+        maybe_install_squashfuse(cloud=FakeCloud(distro))
+        self.assertEqual(
+            [mock.call()], distro.update_package_sources.call_args_list)
+        self.assertEqual(
+            [mock.call(['squashfuse'])],
+            distro.install_packages.call_args_list)
+
+# vi: ts=4 expandtab