Merge pull request #10 from stackhpc/fix/process-lookup-error

Fix occasional ProcessLookupErrors when commands are cancelled

pyhelm3/command.py

@@ -193,8 +193,14 @@ async def run(self, command: t.List[str], input: t.Optional[bytes] = None) -> by
         except asyncio.CancelledError:
             # If the asyncio task is cancelled, terminate the Helm process but let the
             # process handle the termination and exit
-            proc.terminate()
-            stdout, stderr = await proc.communicate()
+            # We occassionally see a ProcessLookupError here if the process finished between
+            # us being cancelled and terminating the process, which we ignore as that is our
+            # target state anyway
+            try:
+                proc.terminate()
+                _ = await proc.communicate()
+            except ProcessLookupError:
+                pass
             # Once the process has exited, re-raise the cancelled error
             raise
         if proc.returncode == 0: