fix: capture data on SIGTERM #1307

This covers multiprocessing.Process.terminate(), and maybe other cases also.

coverage/control.py

@@ -9,6 +9,7 @@
 import os
 import os.path
 import platform
+import signal
 import sys
 import time
 import warnings
@@ -526,6 +527,7 @@ def _init_for_start(self):
         self._should_write_debug = True
 
         atexit.register(self._atexit)
+        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 +585,20 @@ 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, frame):
+        self._atexit("sigterm")
+        signal.signal(signal.SIGTERM, self._old_sigterm)
+        signal.raise_signal(signal.SIGTERM)
+
     def erase(self):
         """Erase previously collected coverage data.
 

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