Add forward_unbound_keys setting

TODO

@@ -2,7 +2,6 @@ keyparser foo
 =============
 
 - Handle keybind to get out of insert mode (e.g. esc)
-- Add passthrough-keys option to pass through unmapped keys
 - Add more element-selection-detection code (with options?) based on:
       -> javascript: http://stackoverflow.com/a/2848120/2085149
       -> microFocusChanged and check active element via:

qutebrowser/commands/keys.py

@@ -85,12 +85,15 @@ class CommandKeyParser(KeyParser):
 
         Emit:
             set_cmd_text: If the keystring should be shown in the statusbar.
+
+        Return:
+            True if event has been handled, False otherwise.
         """
         txt = e.text().strip()
         if not self._keystring and any(txt == c for c in STARTCHARS):
             self.set_cmd_text.emit(txt)
-            return
-        super()._handle_single_key(e)
+            return True
+        return super()._handle_single_key(e)
 
     def execute(self, cmdstr, count=None):
         """Handle a completed keychain."""

qutebrowser/config/configdata.py

@@ -176,6 +176,10 @@ DATA = OrderedDict([
          SettingValue(types.Bool(), "true"),
          "Whether to automatically enter insert mode if an editable element "
          "is focused after page load."),
+
+        ('forward_unbound_keys',
+         SettingValue(types.Bool(), "false"),
+         "Whether to forward unbound keys to the website in normal mode."),
     )),
 
     ('tabbar', sect.KeyValue(

qutebrowser/utils/keyparser.py

@@ -116,12 +116,15 @@ class KeyParser(QObject):
 
         Args:
             e: the KeyPressEvent from Qt.
+
+        Return:
+            True if event has been handled, False otherwise.
         """
         logging.debug('Got key: {} / text: "{}"'.format(e.key(), e.text()))
         txt = e.text().strip()
         if not txt:
             logging.debug('Ignoring, no text')
-            return
+            return False
 
         self._stop_delayed_exec()
         self._keystring += txt
@@ -135,7 +138,8 @@ class KeyParser(QObject):
             count = None
 
         if not cmd_input:
-            return
+            # Only a count, no command yet, but we handled it
+            return True
 
         (match, binding) = self._match_key(cmd_input)
 
@@ -151,6 +155,8 @@ class KeyParser(QObject):
             logging.debug('Giving up with "{}", no matches'.format(
                 self._keystring))
             self._keystring = ''
+            return False
+        return True
 
     def _match_key(self, cmd_input):
         """Try to match a given keystring with any bound keychain.

qutebrowser/utils/modemanager.py

@@ -25,6 +25,8 @@ import logging
 
 from PyQt5.QtCore import pyqtSignal, QObject, QEvent
 
+import qutebrowser.config.config as config
+
 
 manager = None
 
@@ -168,11 +170,19 @@ class ModeManager(QObject):
             return False
         elif typ == QEvent.KeyPress:
             # KeyPress in a non-passthrough mode - call handler and filter
-            # event from widgets
+            # event from widgets (unless unhandled and configured to pass
+            # unhandled events through)
             self.key_pressed.emit(evt)
             if handler is not None:
-                handler(evt)
-            return True
+                handled = handler(evt)
+            else:
+                handled = False
+            if handled:
+                return True
+            elif config.get('general', 'forward_unbound_keys'):
+                return False
+            else:
+                return True
         else:
             # KeyRelease in a non-passthrough mode - filter event and ignore it
             # entirely.