Comment 4 for bug 1239646

for example, a standard button click as in https://jenkins.qa.ubuntu.com/job/generic-mediumtests-runner-maguro/2418/testReport/junit/ubuntuuitoolkit.tests.gallery.test_gallery/ButtonsTestCase/test_buttons_standard_button_/ fails with:

test-log: {{{
13:13:00.735 INFO globals:49 - ************************************************************
13:13:00.736 INFO globals:50 - Starting test ubuntuuitoolkit.tests.gallery.test_gallery.ButtonsTestCase.test_buttons (standard button)
13:13:00.737 WARNING testcase:118 - No tracing available - install the python-autopilot-trace package!
13:13:00.743 WARNING testcase:155 - Process manager backend unavailable, application snapshot support disabled.
13:13:00.971 INFO __init__:156 - Launching process: ['/usr/lib/arm-linux-gnueabihf/qt5/bin/qmlscene', '-testability', '-I/usr/lib/modules', '/usr/lib/ubuntu-ui-toolkit/examples/ubuntu-ui-toolkit-gallery/ubuntu-ui-toolkit-gallery.qml', '--desktop_file_hint=/usr/lib/ubuntu-ui-toolkit/examples/ubuntu-ui-toolkit-gallery/ubuntu-ui-toolkit-gallery.desktop']
13:13:13.188 INFO testcase:552 - waiting for process to exit.
13:13:13.190 INFO testcase:554 - Killing process 2748
}}}

Traceback (most recent call last):
  File "/usr/lib/python2.7/dist-packages/ubuntuuitoolkit/tests/gallery/test_gallery.py", line 39, in setUp
    super(GalleryTestCase, self).setUp()
  File "/usr/lib/python2.7/dist-packages/ubuntuuitoolkit/tests/__init__.py", line 117, in setUp
    self.launch_application()
  File "/usr/lib/python2.7/dist-packages/ubuntuuitoolkit/tests/__init__.py", line 127, in launch_application
    app_type='qt')
  File "/usr/lib/python2.7/dist-packages/autopilot/testcase.py", line 284, in launch_test_application
    dbus_bus
  File "/usr/lib/python2.7/dist-packages/autopilot/introspection/__init__.py", line 187, in get_autopilot_proxy_object_for_process
    dbus_bus=dbus_bus,
  File "/usr/lib/python2.7/dist-packages/autopilot/introspection/__init__.py", line 271, in get_proxy_object_for_existing_process
    raise ProcessSearchError("Search criteria returned no results")
ProcessSearchError: Search criteria returned no results

So it seems to fail in opening the application from tests/__init__.py in:

    def launch_application(self):
        desktop_file_path = self._get_desktop_file_path()
        self.app = self.launch_test_application(
            base.get_qmlscene_launch_command(),
            "-I" + _get_module_include_path(),
            self.test_qml_file_path,
            '--desktop_file_hint={0}'.format(desktop_file_path),
            emulator_base=emulators.UbuntuUIToolkitEmulatorBase,
            app_type='qt')