Use a subdirectory of the state partition

tests/integration/rostest/conftest.py

@@ -2,11 +2,12 @@ import subprocess
 
 import os
 import pytest
+import rostest
 
 
 @pytest.fixture(scope="session", autouse=True)
 def chdir_to_project_root():
-    os.chdir('../..')
+    os.chdir(os.path.join(os.path.dirname(rostest.__file__), '../../..'))
     print('\nChdir to project root dir: ' + subprocess.check_output('pwd'))
     os.chmod('./tests/integration/assets/test.key', 0o600)
     print('Also, `chmod 600 tests/integration/assets/test.key` to make ssh happy')

tests/integration/rostest/test_06_subdir.py

@@ -0,0 +1,19 @@
+import pytest
+import rostest.util as u
+from rostest.util import SSH
+
+
+@pytest.fixture(scope="module")
+def qemu(request):
+    q = u.run_qemu(request, run_args=['--append', 'rancher.state.directory=ros_subdir'])
+    u.flush_out(q.stdout)
+    return q
+
+
+def test_system_docker_survives_custom_docker_install(qemu):
+    SSH(qemu).check_call('bash', '-c', '''
+        set -x -e
+        mkdir x
+        sudo mount $(ros dev LABEL=RANCHER_STATE) x
+        [ -d x/ros_subdir/home/rancher ]
+    '''.strip())

tests/integration/rostest/util.py

@@ -85,3 +85,19 @@ def wait_for_ssh(qemu, ssh_command=['./scripts/ssh', '--qemu'], command=['docker
         print('\nWaiting for ssh and docker... ' + str(i))
         time.sleep(1)
         assert qemu.returncode is None
+
+
+class SSH:
+    def __init__(self, qemu, ssh_command=['./scripts/ssh', '--qemu']):
+        self._qemu = qemu
+        self._ssh_command = ssh_command
+        self._waited = False
+
+    def check_call(self, *args, **kw):
+        if not self._waited:
+            wait_for_ssh(self._qemu, ssh_command=self._ssh_command)
+            self._waited = True
+
+        kw['stderr'] = subprocess.STDOUT
+        kw['universal_newlines'] = True
+        return subprocess.check_call(self._ssh_command + list(args), **kw)