Run unit tests in isolation w/ coverage support.

.coveragerc

@@ -9,6 +9,7 @@ branch = True
 # results from multiple tests simultaneously, as well as supporting multiple
 # test runs, such as from integration tests.
 concurrency = multiprocessing
+parallel = True
 
 # When running tests through ansible-test, this option is overridden by
 # the COVERAGE_FILE environment variable. This option is present for

test/runner/injector/injector.py

@@ -144,7 +144,6 @@ def coverage_command(self_dir, version):
     args = [
         find_executable(executable),
         'run',
-        '--append',
         '--rcfile',
         os.path.join(self_dir, '.coveragerc'),
     ]

test/runner/lib/executor.py

@@ -624,6 +624,7 @@ def command_units(args):
 
         cmd = [
             'pytest',
+            '--boxed',
             '-r', 'a',
             '--color',
             'yes' if args.color else 'no',

test/runner/requirements/units.txt

@@ -6,6 +6,7 @@ passlib
 pycrypto
 pytest
 pytest-mock
+pytest-xdist
 python-memcached
 pyyaml
 redis

test/units/conftest.py

@@ -0,0 +1,33 @@
+"""Monkey patch os._exit when running under coverage so we don't lose coverage data in forks, such as with `pytest --boxed`."""
+import gc
+import os
+
+try:
+    import coverage
+except ImportError:
+    coverage = None
+
+
+def pytest_configure():
+    if not coverage:
+        return
+
+    coverage_instances = []
+
+    for obj in gc.get_objects():
+        if isinstance(obj, coverage.Coverage):
+            coverage_instances.append(obj)
+
+    if not coverage_instances:
+        return
+
+    os_exit = os._exit
+
+    def coverage_exit(*args, **kwargs):
+        for instance in coverage_instances:
+            instance.stop()
+            instance.save()
+
+        os_exit(*args, **kwargs)
+
+    os._exit = coverage_exit