Correct fix for ignoring BrokenPipeError

kitty/boss.py

@@ -106,6 +106,7 @@ class Boss:
 
     def __init__(self, os_window_id, opts, args, cached_values, new_os_window_trigger):
         set_draw_minimal_borders(opts)
+        self.update_check_process = None
         self.window_id_map = WeakValueDictionary()
         self.startup_colors = {k: opts[k] for k in opts if isinstance(opts[k], Color)}
         self.startup_cursor_text_color = opts.cursor_text_color
@@ -778,6 +779,7 @@ class Boss:
     def destroy(self):
         self.shutting_down = True
         self.child_monitor.shutdown_monitor()
+        self.update_check_process = None
         del self.child_monitor
         for tm in self.os_window_map.values():
             tm.destroy()
@@ -992,8 +994,6 @@ class Boss:
             from .update_check import process_current_release
             try:
                 raw = update_check_process.stdout.read().decode('utf-8')
-            except BrokenPipeError:
-                pass
             except Exception as e:
                 log_error('Failed to read data from update check process, with error: {}'.format(e))
             else:

kitty/update_check.py

@@ -96,11 +96,21 @@ def process_current_release(raw):
         notify_new_version(release_version)
 
 
+def run_worker():
+    import time
+    import random
+    time.sleep(random.randint(1000, 4000) / 1000)
+    try:
+        print(get_released_version())
+    except BrokenPipeError:
+        pass  # happens if parent process is killed before us
+
+
 def update_check(timer_id=None):
     try:
         p = subprocess.Popen([
             kitty_exe(), '+runpy',
-            'from kitty.update_check import *; import time, random; time.sleep(random.randint(1000, 4000) / 1000); print(get_released_version())'
+            'from kitty.update_check import run_worker; run_worker()'
         ], stdout=subprocess.PIPE)
     except EnvironmentError as e:
         log_error('Failed to run kitty for update check, with error: {}'.format(e))