[orca] Fix for bug 640218 - Handle pyatspi LookupError exceptions better; more work on bug 640132.

[Joanmarie Diggs <joanied src gnome org>]

commit ec21d18132aa07edb0037459b3ce3b996bf3009d
Author: Joanmarie Diggs <joanmarie diggs gmail com>
Date:   Fri Jan 21 15:26:01 2011 -0500

    Fix for bug 640218 - Handle pyatspi LookupError exceptions better; more work on bug 640132.

 src/orca/event_manager.py                 |    8 ++------
 src/orca/orca.py                          |   22 ++++++++++++++++++----
 src/orca/script_manager.py                |   15 +++++++++++----
 src/orca/scripts/toolkits/Gecko/script.py |   19 ++++++++++++++-----
 4 files changed, 45 insertions(+), 19 deletions(-)
---
diff --git a/src/orca/event_manager.py b/src/orca/event_manager.py
index 43e03b8..b638d77 100644
--- a/src/orca/event_manager.py
+++ b/src/orca/event_manager.py
@@ -303,13 +303,10 @@ class EventManager:
         - eventType: the event type.
         """
 
-        try:
-            self._listenerCounts[eventType] -= 1
-        except KeyError:
-            debug.println(debug.LEVEL_SEVERE,
-                          "KeyError deregistering %s listener" % eventType)
+        if not eventType in self._listenerCounts:
             return
 
+        self._listenerCounts[eventType] -= 1
         if self._listenerCounts[eventType] == 0:
             self.registry.deregisterEventListener(self._enqueue, eventType)
             del self._listenerCounts[eventType]
@@ -453,7 +450,6 @@ class EventManager:
         try:
             state = event.source.getState()
         except LookupError:
-            debug.printException(debug.LEVEL_WARNING)
             debug.println(debug.LEVEL_WARNING,
                           "LookupError while processing event: %s" % eType)
             if eType.startswith("window:deactivate"):
diff --git a/src/orca/orca.py b/src/orca/orca.py
index 1560cb0..a0c3b01 100644
--- a/src/orca/orca.py
+++ b/src/orca/orca.py
@@ -602,8 +602,13 @@ def setLocusOfFocus(event, obj, notifyScript=True, force=False):
     if event and event.source and \
        event.host_application and orca_state.activeScript:
         currentApp = orca_state.activeScript.app
-        if currentApp != event.host_application and \
-           currentApp != event.source.getApplication():
+        try:
+            appList = [event.host_application, event.source.getApplication()]
+        except LookupError:
+            appList = []
+            debug.printlin(debug.LEVEL_SEVERE,
+                           "orca.setLocusOfFocus() application LookupError")
+        if not currentApp in appList:
             return
 
     oldLocusOfFocus = orca_state.locusOfFocus
@@ -965,9 +970,18 @@ def keyEcho(event):
     # If this keyboard event was for an object like a password text
     # field, then don't echo it.
     #
-    if orca_state.locusOfFocus \
-        and (orca_state.locusOfFocus.getRole() == pyatspi.ROLE_PASSWORD_TEXT):
+    try:
+        role = orca_state.locusOfFocus.getRole()
+    except LookupError:
+        debug.println(debug.LEVEL_SEVERE,
+                      "orca.keyEcho() - locusOfFocus no longer exists")
+        setLocusOfFocus(None, None, False)
         return False
+    except:
+        pass
+    else:
+        if role == pyatspi.ROLE_PASSWORD_TEXT:
+            return False
 
     event_string = event.event_string
     debug.println(debug.LEVEL_FINEST,
diff --git a/src/orca/script_manager.py b/src/orca/script_manager.py
index da0c3af..d9bba5d 100644
--- a/src/orca/script_manager.py
+++ b/src/orca/script_manager.py
@@ -108,8 +108,14 @@ class ScriptManager:
 
         name = ''
         if obj:
-            attrs = dict([attr.split(':', 1) for attr in obj.getAttributes()])
-            name = attrs.get('toolkit', '')
+            try:
+                attributes = obj.getAttributes()
+            except LookupError:
+                debug.println(debug.LEVEL_SEVERE,
+                              "_toolkitForObject: %s no longer exists" % obj)
+            else:
+                attrs = dict([attr.split(':', 1) for attr in attributes])
+                name = attrs.get('toolkit', '')
 
         return name
 
@@ -244,9 +250,10 @@ class ScriptManager:
             debug.printException(debug.LEVEL_FINEST)
             return
 
-        appList = filter(lambda a: a not in desktop, self.scripts.keys())
+        appList = self.scripts.keys()
+        appList = filter(lambda a: a!= None and a not in desktop, appList)
         for app in appList:
-            script = self.scripts.get(app)
+            script = self.scripts.pop(app)
             _eventManager.deregisterListeners(script)
             del app
             del script
diff --git a/src/orca/scripts/toolkits/Gecko/script.py b/src/orca/scripts/toolkits/Gecko/script.py
index ea4f110..17f3548 100644
--- a/src/orca/scripts/toolkits/Gecko/script.py
+++ b/src/orca/scripts/toolkits/Gecko/script.py
@@ -2817,12 +2817,21 @@ class Script(default.Script):
            indicates that we want Firefox to handle key commands.
         """
 
-        # If the current object isn't even showing, we don't want to hand
-        # this off to Firefox's native caret navigation because who knows
-        # where we'll wind up....
-        #
-        if obj and not obj.getState().contains(pyatspi.STATE_SHOWING):
+        try:
+            state = obj.getState()
+        except LookupError:
+            debug.println(debug.LEVEL_SEVERE,
+                          "isNavigableAria() - obj no longer exists")
             return True
+        except:
+            pass
+        else:
+            # If the current object isn't even showing, we don't want to hand
+            # this off to Firefox's native caret navigation because who knows
+            # where we'll wind up....
+            #
+            if state.contains(pyatspi.STATE_SHOWING):
+                return True
 
         # Sometimes the child of an ARIA widget claims focus. It may lack
         # the attributes we're looking for. Therefore, if obj is not an