Add tests for reaping-on-signal behavior

tests/child_scripts/signalsupervisor.py

@@ -0,0 +1,40 @@
+"""
+Start a child process that prints signals it receives
+"""
+import asyncio
+import signal
+import os
+from functools import partial
+import sys
+from simpervisor import SupervisedProcess
+
+signal_printer = os.path.join(
+    os.path.dirname(os.path.abspath(__file__)),
+    'signalprinter.py'
+)
+
+async def main():
+    count = int(sys.argv[1])
+    pids = []
+    for i in range(count):
+        proc = SupervisedProcess(f'signalprinter-{i}', *[
+            sys.executable,
+            signal_printer, '1'
+        ])
+
+        await proc.start()
+        pids.append(proc.pid)
+
+    print(' '.join([str(pid) for pid in pids]), flush=True)
+
+
+
+loop = asyncio.get_event_loop()
+asyncio.ensure_future(main())
+try:
+    loop.run_forever()
+finally:
+    # Cleanup properly so we get a clean exit
+    loop.run_until_complete(asyncio.gather(*asyncio.Task.all_tasks()))
+    print('supervisor exiting cleanly')
+    loop.close()

tests/test_signals.py

@@ -0,0 +1,49 @@
+import sys
+import signal
+import os
+import pytest
+from simpervisor import SupervisedProcess
+import subprocess
+import time
+import errno
+
+
+@pytest.mark.parametrize('childcount', [1, 5])
+@pytest.mark.asyncio
+async def test_sigtermreap(childcount):
+    """
+    Test reaping subprocess after SIGTERM.
+
+    - Start a supervisor process that supervises a child.
+    - Send supervisor a SIGTERM
+    - Make sure child receives it & exits first before supervisor exiting
+    """
+    signalsupervisor_file = os.path.join(
+        os.path.dirname(os.path.abspath(__file__)),
+        'child_scripts',
+        'signalsupervisor.py'
+    )
+
+    proc = subprocess.Popen([sys.executable, signalsupervisor_file, str(childcount)], stdout=subprocess.PIPE)
+
+    # Give the signal handlers a bit of time to set up
+    time.sleep(0.5)
+
+    # Read the child's PID from signalsupervisor
+    child_pids = [int(l) for l in proc.stdout.readline().decode().split(' ')]
+
+    proc.send_signal(signal.SIGTERM)
+    proc.wait()
+
+    stdout, stderr = proc.communicate()
+
+    # Make sure the children are dead
+    for child_pid in child_pids:
+        with pytest.raises(OSError) as e:
+            os.kill(child_pid, 0)
+        assert e.value.errno == errno.ESRCH
+
+    # Test order of exit of child & parent
+    assert stdout.decode() == 'handler 0 received 15\n' * len(child_pids) + 'supervisor exiting cleanly\n'
+    # Test that our supervisor also exited cleanly
+    assert proc.returncode == 0