Don't lose warnings shown in early init phases

qutebrowser/mainwindow/mainwindow.py

@@ -437,6 +437,7 @@ class MainWindow(QWidget):
         # messages
         message.global_bridge.show_message.connect(
             self._messageview.show_message)
+        message.global_bridge.flush()
 
         message_bridge.s_set_text.connect(status.set_text)
         message_bridge.s_maybe_reset_text.connect(status.txt.maybe_reset_text)

qutebrowser/utils/message.py

@@ -61,8 +61,7 @@ def error(message, *, stack=None, replace=False):
         typ = 'error (from exception)'
     _log_stack(typ, stack)
     log.message.error(message)
-    global_bridge.show_message.emit(usertypes.MessageLevel.error, message,
-                                    replace)
+    global_bridge.show(usertypes.MessageLevel.error, message, replace)
 
 
 def warning(message, *, replace=False):
@@ -74,8 +73,7 @@ def warning(message, *, replace=False):
     """
     _log_stack('warning', traceback.format_stack())
     log.message.warning(message)
-    global_bridge.show_message.emit(usertypes.MessageLevel.warning, message,
-                                    replace)
+    global_bridge.show(usertypes.MessageLevel.warning, message, replace)
 
 
 def info(message, *, replace=False):
@@ -86,8 +84,7 @@ def info(message, *, replace=False):
         replace: Replace existing messages with replace=True
     """
     log.message.info(message)
-    global_bridge.show_message.emit(usertypes.MessageLevel.info, message,
-                                    replace)
+    global_bridge.show(usertypes.MessageLevel.info, message, replace)
 
 
 def _build_question(title, text=None, *, mode, default=None, abort_on=()):
@@ -173,6 +170,10 @@ class GlobalMessageBridge(QObject):
 
     """Global (not per-window) message bridge for errors/infos/warnings.
 
+    Attributes:
+        _connected: Whether a slot is connected and we can show messages.
+        _cache: Messages shown while we were not connected.
+
     Signals:
         show_message: Show a message
                       arg 0: A MessageLevel member
@@ -194,6 +195,11 @@ class GlobalMessageBridge(QObject):
     ask_question = pyqtSignal(usertypes.Question, bool)
     mode_left = pyqtSignal(usertypes.KeyMode)
 
+    def __init__(self, parent=None):
+        super().__init__(parent)
+        self._connected = False
+        self._cache = []
+
     def ask(self, question, blocking, *, log_stack=False):
         """Ask a question to the user.
 
@@ -208,6 +214,23 @@ class GlobalMessageBridge(QObject):
         """
         self.ask_question.emit(question, blocking)
 
+    def show(self, level, text, replace=False):
+        if self._connected:
+            self.show_message.emit(level, text, replace)
+        else:
+            self._cache.append((level, text, replace))
+
+    def flush(self):
+        """Flush messages which accumulated while no handler was connected.
+
+        This is so we don't miss messages shown during some early init phase.
+        It needs to be called once the show_message signal is connected.
+        """
+        self._connected = True
+        for args in self._cache:
+            self.show(*args)
+        self._cache = []
+
 
 class MessageBridge(QObject):
 

tests/helpers/messagemock.py

@@ -70,6 +70,7 @@ class MessageMock:
     def patch(self):
         """Start recording messages."""
         message.global_bridge.show_message.connect(self._record_message)
+        message.global_bridge._connected = True
 
     def unpatch(self):
         """Stop recording messages."""