There were two broad issues with fixtures.
Firstly, the 'SafeFixture' workaround for resource leaks in fixtures
<1.3 is not needed if we depend on fixtures>=1.3.1. While testtools
may raise a TypeError when trying to query a fixture that failed to
setup, this is only ever a cascading failure - it will not cause
tests to fail, cause leaks, or cause tests to incorrectly pass. That
will be fixed in testtools soon to stop it happening (but as it cannot
affect whether a test passes or fails or leaks happen there is no
reason to wait for that). Leaks are seen with fixtures 1.3.0 still
because eventlet raises a BaseException subclass rather than an
Exception subclass, and fixtures 1.3.0 didn't handle that - 1.3.1 does.
Secondly, some of the fixtures had race conditions where things were
started and then cleanups scheduled. Where possible I've fixed those,
but some of them require more significant work to fully address.
Change-Id: I3290712f7274970defda19263f4955e3c78e5ed6
Depends-On: I8c01506894ec0a92b53bc0e4ad14767f2dd6a6b3
Closes-bug: #1453888
7344e3ab8e