Also prevent long running diff workers from causing a hang on exit

kittens/diff/main.py

@@ -25,7 +25,7 @@ from .collect import (
     set_highlight_data
 )
 from .config import init_config
-from .patch import Differ, set_diff_command
+from .patch import Differ, set_diff_command, worker_processes
 from .render import ImageSupportWarning, LineRef, render_diff
 from .search import BadRegex, Search
 
@@ -511,9 +511,10 @@ usage = 'file_or_directory_left file_or_directory_right'
 
 def terminate_processes(processes):
     for pid in processes:
-        os.kill(pid, signal.SIGTERM)
-    for pid in processes:
-        os.kill(pid, signal.SIGKILL)
+        try:
+            os.kill(pid, signal.SIGKILL)
+        except Exception:
+            pass
 
 
 def main(args):
@@ -538,8 +539,9 @@ def main(args):
     for message in showwarning.warnings:
         from kitty.utils import safe_print
         safe_print(message, file=sys.stderr)
-    processes = getattr(highlight_collection, 'processes', ())
-    terminate_processes(tuple(processes))
+    highlight_processes = getattr(highlight_collection, 'processes', ())
+    terminate_processes(tuple(highlight_processes))
+    terminate_processes(tuple(worker_processes))
     if loop.return_code != 0:
         if handler.report_traceback_on_exit:
             print(handler.report_traceback_on_exit, file=sys.stderr)