tests leave threads behind

[John A Meinel]

As part of getting the test suite to run under Launchpad, I see these new warnings:

The following test left new threads behind:
test_run_script (loggerhead.tests.test_load_test.TestRunScript)
New thread(s): [<Thread(Thread-16, started daemon 140427624232704)>, <Thread(Thread-18, started daemon 140427632625408)>, <Thread(Thread-17, started daemon 140427615840000)>, <Thread(Thread-14, started daemon 140427693524736)>]
 test_files_file (loggerhead.tests.test_simple.TestControllerRedirects)
 test_view_folder (loggerhead.tests.test_simple.TestControllerRedirects)
 test_changes (loggerhead.tests.test_simple.TestEmptyBranch)
 test_inventory (loggerhead.tests.test_simple.TestEmptyBranch)
 test_get (loggerhead.tests.test_simple.TestHeadMiddleware)
 test_head (loggerhead.tests.test_simple.TestHeadMiddleware)
 test_no_access (loggerhead.tests.test_simple.TestHiddenBranch)
 test_annotate (loggerhead.tests.test_simple.TestWithSimpleTree)
 test_changes (loggerhead.tests.test_simple.TestWithSimpleTree)
 test_changes_branch_from (loggerhead.tests.test_simple.TestWithSimpleTree)
 test_changes_for_file (loggerhead.tests.test_simple.TestWithSimpleTree)
 test_changes_search (loggerhead.tests.test_simple.TestWithSimpleTree)
 test_inventory (loggerhead.tests.test_simple.TestWithSimpleTree)
 test_inventory_bad_path_404 (loggerhead.tests.test_simple.TestWithSimpleTree)
 test_inventory_bad_rev_404 (loggerhead.tests.test_simple.TestWithSimpleTree)
 test_revision (loggerhead.tests.test_simple.TestWithSimpleTree)
 test_author_is_committer (loggerhead.tests.test_revision_ui.TestRevisionUI)
 test_authors_vs_committer (loggerhead.tests.test_revision_ui.TestRevisionUI)
 test_html_escape (loggerhead.tests.test_util.TestHTMLEscaping)
 test_html_format (loggerhead.tests.test_util.TestHTMLEscaping)
 launchpad_loggerhead.tests.TestOopsMiddleware.test_exception_triggers_oops
 launchpad_loggerhead.tests.TestOopsMiddleware.test_ignores_socket_exceptions
 launchpad_loggerhead.tests.TestOopsMiddleware.test_ignores_writer_failures
 launchpad_loggerhead.tests.TestOopsMiddleware.test_no_body_calls_start_response
 launchpad_loggerhead.tests.TestOopsMiddleware.test_stopping_early_no_oops
  Ran 79 tests with 0 failures and 0 errors in 3.757 seconds.
  Tear down zope.testing.testrunner.layer.UnitTests in 0.000 seconds.
Total: 81 tests, 0 failures, 0 errors in 14.607 seconds.

I have a feeling something in the 'setUpLoggerhead' sort of functions is spawning a new thread, and not joining it correctly.

It doesn't seem to cause the test suite to fail, so it doesn't block us from running the tests as part of the loggerhead suite.

Note that bzr's test runner doesn't seem to complain about threads leaking, so it might be specific to Launchpad's test runner. (though that seems odd.)

[Robert Collins (lifeless)]

launchpads test runner does indeed have a thread introspection thing. whether that is a good idea is a separate discussion :)