Comment 1 for bug 1060616

lp.registry.tests.test_distributionmirror_prober.TestProberProtocolAndFactory.test_connect_to_proxy_when_http_proxy_exists
 is the last actual test before stream data gets exposed, and lp.testing.layers.YUIAppServerLayer:setUp is the last virtual test:
"
lp.registry.tests.test_distributionmirror_prober.TestProberProtocolAndFactory.test_connect_to_proxy_when_http_proxy_exists
lp.testing.layers.TwistedLayer:tearDown
lp.testing.layers.BaseLayer:tearDown
Running in a subprocess.
lp.testing.layers.BaseLayer:setUp
lp.testing.layers.MemcachedLayer:setUp
lp.testing.layers.YUIAppServerLayer:setUp
test: Could not communicate with subprocess
successful: Could not communicate with subprocess
"

Note that 'Running in a subprocess.\n'

should be 'test: Running in a subprocess.\n' -s the corruption is ~ there.

looking at the raw stream we see:"
test: lp.testing.layers.YUIAppServerLayer:setUp
tags: zope:layer
time: 2012-10-03 04:01:37.335434Z
successful: lp.testing.layers.YUIAppServerLayer:setUp
tags: zope:layer:lp.testing.layers.YUIAppServerLayer
time: 2012-10-03 04:01:37.775637Z
test: lp/testing/tests/test_yuixhr_fixture_facet
test: Could not communicate with subprocess
tags: zope:error_with_banner
successful: Could not communicate with subprocess
"

Which suggests that lp/testing/tests/test_yuixhr_fixture_facet is failing sufficiently hard that the finally: block which should be reporting on the test failure isn't executing at all - not even enough to report that it didn't complete the test.