diff --git a/coverage/control.py b/coverage/control.py index bd51ffc56..623ecf6cb 100644 --- a/coverage/control.py +++ b/coverage/control.py @@ -9,6 +9,7 @@ import os import os.path import platform +import signal import sys import time import warnings @@ -228,6 +229,7 @@ def __init__( self._exclude_re = None self._debug = None self._file_mapper = None + self._old_sigterm = None # State machine variables: # Have we initialized everything? @@ -526,6 +528,11 @@ def _init_for_start(self): self._should_write_debug = True atexit.register(self._atexit) + if not env.WINDOWS: + # The Python docs seem to imply that SIGTERM works uniformly even + # on Windows, but that's not my experience, and this agrees: + # https://stackoverflow.com/questions/35772001/x/35792192#35792192 + self._old_sigterm = signal.signal(signal.SIGTERM, self._on_sigterm) def _init_data(self, suffix): """Create a data file if we don't have one yet.""" @@ -583,15 +590,21 @@ def stop(self): self._collector.stop() self._started = False - def _atexit(self): + def _atexit(self, event="atexit"): """Clean up on process shutdown.""" if self._debug.should("process"): - self._debug.write(f"atexit: pid: {os.getpid()}, instance: {self!r}") + self._debug.write(f"{event}: pid: {os.getpid()}, instance: {self!r}") if self._started: self.stop() if self._auto_save: self.save() + def _on_sigterm(self, signum_unused, frame_unused): + """A handler for signal.SIGTERM.""" + self._atexit("sigterm") + signal.signal(signal.SIGTERM, self._old_sigterm) + os.kill(os.getpid(), signal.SIGTERM) + def erase(self): """Erase previously collected coverage data. diff --git a/coverage/multiproc.py b/coverage/multiproc.py index 1f9225f3e..3a9bd6339 100644 --- a/coverage/multiproc.py +++ b/coverage/multiproc.py @@ -27,7 +27,7 @@ def _bootstrap(self, *args, **kwargs): """Wrapper around _bootstrap to start coverage.""" try: from coverage import Coverage # avoid circular import - cov = Coverage(data_suffix=True) + cov = Coverage(data_suffix=True, auto_data=True) cov._warn_preimported_source = False cov.start() debug = cov._debug diff --git a/tests/test_concurrency.py b/tests/test_concurrency.py index 001455f26..14dfc5ca6 100644 --- a/tests/test_concurrency.py +++ b/tests/test_concurrency.py @@ -693,3 +693,82 @@ def random_load(): # pragma: nested finally: os.chdir(old_dir) should_run[0] = False + + +@pytest.mark.skipif(env.WINDOWS, reason="SIGTERM doesn't work the same on Windows") +class SigtermTest(CoverageTest): + """Tests of our handling of SIGTERM.""" + + def test_sigterm_saves_data(self): + # A terminated process should save its coverage data. + self.make_file("clobbered.py", """\ + import multiprocessing + import time + + def subproc(x): + if x.value == 3: + print("THREE", flush=True) # line 6, missed + else: + print("NOT THREE", flush=True) + x.value = 0 + time.sleep(60) + + if __name__ == "__main__": + print("START", flush=True) + x = multiprocessing.Value("L", 1) + proc = multiprocessing.Process(target=subproc, args=(x,)) + proc.start() + while x.value != 0: + time.sleep(.05) + proc.terminate() + print("END", flush=True) + """) + self.make_file(".coveragerc", """\ + [run] + parallel = True + concurrency = multiprocessing + """) + out = self.run_command("coverage run clobbered.py") + # Under the Python tracer on Linux, we get the "Trace function changed" + # message. Does that matter? + if "Trace function changed" in out: + lines = out.splitlines(True) + assert len(lines) == 5 # "trace function changed" and "self.warn(" + out = "".join(lines[:3]) + assert out == "START\nNOT THREE\nEND\n" + self.run_command("coverage combine") + out = self.run_command("coverage report -m") + assert self.squeezed_lines(out)[2] == "clobbered.py 17 1 94% 6" + + def test_sigterm_still_runs(self): + # A terminated process still runs its own SIGTERM handler. + self.make_file("handler.py", """\ + import multiprocessing + import signal + import time + + def subproc(x): + print("START", flush=True) + def on_sigterm(signum, frame): + print("SIGTERM", flush=True) + + signal.signal(signal.SIGTERM, on_sigterm) + x.value = 0 + time.sleep(.1) + print("END", flush=True) + + if __name__ == "__main__": + x = multiprocessing.Value("L", 1) + proc = multiprocessing.Process(target=subproc, args=(x,)) + proc.start() + while x.value != 0: + time.sleep(.02) + proc.terminate() + """) + self.make_file(".coveragerc", """\ + [run] + parallel = True + concurrency = multiprocessing + """) + out = self.run_command("coverage run handler.py") + assert out == "START\nSIGTERM\nEND\n"