still trying to fix the gfile monitoring code

Author: maoschanz

src/image.py

@@ -226,10 +226,10 @@ def reload_from_disk(self):
 			return
 		disk_pixbuf = GdkPixbuf.Pixbuf.new_from_file(self.get_file_path())
 		self._load_pixbuf_common(disk_pixbuf)
-		self.window.update_picture_title()
 		self.use_stable_pixbuf()
 		self.update()
 		self.remember_current_state()
+		self.window.update_picture_title()
 
 	def try_load_file(self, gfile):
 		try:
@@ -250,6 +250,12 @@ def try_load_file(self, gfile):
 		self._update_can_reload_action()
 
 	def _connect_gfile_monitoring(self):
+		if self._gfile_monitor:
+			# Probably no need to reconnect it again.
+			# XXX est-il vraiment bon ? on devrait le déconnecter, le refaire ?
+			# Tout cela n'est pas débuggable parce que le fichier que je traque
+			# est le proxy de la sandbox (/run/user/1000/...)
+			self._gfile_monitor = None
 		flags = Gio.FileMonitorFlags.WATCH_MOUNTS
 		self._gfile_monitor = self.gfile.monitor(flags)
 		self._gfile_monitor.connect('changed', self.reveal_reload_message)
@@ -258,13 +264,29 @@ def disable_monitoring(self):
 		self._monitoring_disabled = True
 
 	def enable_monitoring(self):
+		"""This should only be called initially, or asynchronously, or in case
+		of an exception"""
 		self._monitoring_disabled = False
 
 	def reveal_reload_message(self, *args):
+		"""This method is called when the file changed, which is async: we can't
+		enable or disable the monitoring in the DrSavingManager's method because
+		saving the pixbuf takes longer to trigger the 'changed' signal on the
+		monitor than it takes to run the end of the saving process."""
+		# I'm not sure this lock is 100% correct because i'm monitoring the
+		# portal proxy file when testing with flatpak.
 		if self._monitoring_disabled:
-			# I'm not sure this lock is 100% correct because i'm monitoring the
-			# portal proxy file when testing with flatpak. Better than nothing.
+			# The idea is that the message banner is temporarily disabled until
+			# the monitor sends its next "changed" event, which we expect (it's
+			# the one from our own saving process).
 			if args[3] != Gio.FileMonitorEvent.CHANGED:
+				try:
+					self.reload_from_disk()
+				except Exception as ex:
+					print(e)
+					# Context: an error message
+					self._window.reveal_message(_("Failed to reload %s") % \
+					                                      self.gfile.get_path())
 				self.enable_monitoring()
 			return
 		self._update_can_reload_action()
@@ -556,12 +578,11 @@ def on_enter_image(self, *args):
 	def on_leave_image(self, *args):
 		self.window.set_cursor(False)
 
-	def post_save(self, gfile):
+	def pre_save(self, gfile):
+		"""The gfile is set before saving, because reveal_reload_message expects
+		self.gfile to be correct."""
 		self.gfile = gfile
 		self._connect_gfile_monitoring()
-		self.use_stable_pixbuf()
-		self.update()
-		self.reload_from_disk()
 
 	def set_surface_as_stable_pixbuf(self):
 		w = self.surface.get_width()

src/saving_manager.py

@@ -85,8 +85,10 @@ def save_current_image(self, is_export, to_new, selection_only, allow_alpha):
 				# Context: an error message
 				self._window.reveal_message(_("Failed to replace transparency"))
 
-		# The "reload?" message shouldn't be shown, i force the reload later
-		image.lock_monitoring(False)
+		if not is_export:
+			image.pre_save(gfile)
+			# The "reload?" message shouldn't be shown, i force the reload later
+			image.disable_monitoring()
 
 		try:
 			# Actually save the pixbuf to the given file path
@@ -98,18 +100,9 @@ def save_current_image(self, is_export, to_new, selection_only, allow_alpha):
 			image.enable_monitoring()
 			return False
 
-		# Reset the file monitoring flag
-		image.lock_monitoring(True)
-
-		if not is_export:
-			# Update the image and the window objects
-			try:
-				image.post_save(gfile)
-			except Exception as e:
-				print(e)
-				# Context: an error message
-				self._window.reveal_message(_("Failed to reload %s") % file_path)
-				return False
+		# The file monitoring flag shall reset itself asynchronously.
+		# If it doesn't, i don't care that much tbh it's just a message for a
+		# smoother UX.
 
 		# everything went fine, return true
 		return True