1 files changed, 28 insertions, 0 deletions
diff --git a/cloudinit/config/tests/test_mounts.py b/cloudinit/config/tests/test_mounts.py
new file mode 100644
index 00000000..764a33e3
--- /dev/null
+++ b/cloudinit/config/tests/test_mounts.py
@@ -0,0 +1,28 @@
+# This file is part of cloud-init. See LICENSE file for license information.
+from unittest import mock
+
+import pytest
+
+from cloudinit.config.cc_mounts import create_swapfile
+
+
+M_PATH = 'cloudinit.config.cc_mounts.'
+
+
+class TestCreateSwapfile:
+
+    @pytest.mark.parametrize('fstype', ('xfs', 'btrfs', 'ext4', 'other'))
+    @mock.patch(M_PATH + 'util.get_mount_info')
+    @mock.patch(M_PATH + 'subp.subp')
+    def test_happy_path(self, m_subp, m_get_mount_info, fstype, tmpdir):
+        swap_file = tmpdir.join("swap-file")
+        fname = str(swap_file)
+
+        # Some of the calls to subp.subp should create the swap file; this
+        # roughly approximates that
+        m_subp.side_effect = lambda *args, **kwargs: swap_file.write('')
+
+        m_get_mount_info.return_value = (mock.ANY, fstype)
+
+        create_swapfile(fname, '')
+        assert mock.call(['mkswap', fname]) in m_subp.call_args_list