[gtksourceview] CompletionContext: dispose() gracefully on buffer change

[Sébastien Wilmet <swilmet src gnome org>]

commit 31dc73a5e6f53d0c19c6a72b2878d4160208a4e5
Author: Sébastien Wilmet <swilmet gnome org>
Date:   Fri Jun 27 22:52:11 2014 +0200

    CompletionContext: dispose() gracefully on buffer change
    
    The buffer can change during dispose(), as explained in the code.
    The commit here doesn't fix all the issue, but dispose() should now run
    correctly if the buffer changed.

 gtksourceview/gtksourcecompletioncontext.c |   46 ++++++++++++++--------------
 1 files changed, 23 insertions(+), 23 deletions(-)
---
diff --git a/gtksourceview/gtksourcecompletioncontext.c b/gtksourceview/gtksourcecompletioncontext.c
index 3cd9345..47840c6 100644
--- a/gtksourceview/gtksourcecompletioncontext.c
+++ b/gtksourceview/gtksourcecompletioncontext.c
@@ -72,8 +72,6 @@ struct _GtkSourceCompletionContextPrivate
 
        GtkTextMark *mark;
        GtkSourceCompletionActivation activation;
-
-       gulong mark_set_id;
 };
 
 /* Properties */
@@ -98,10 +96,14 @@ guint context_signals[NUM_SIGNALS] = {0,};
 G_DEFINE_TYPE_WITH_PRIVATE (GtkSourceCompletionContext, gtk_source_completion_context, 
G_TYPE_INITIALLY_UNOWNED)
 
 /* FIXME: we use this util to get the buffer from the completion
-   but this object is not robust to a change of the buffer associated
-   to the view. Context lifetime should be short enough to not really
-   matter.
-*/
+ * but this object is not robust to a change of the buffer associated
+ * to the view. Context lifetime should be short enough to not really
+ * matter.
+ * (swilmet) This can happen when the GtkSourceView is being destroyed:
+ * GtkTextView set the buffer to NULL, then the code here calls
+ * gtk_text_view_get_buffer() which creates another buffer... So it would be
+ * better to handle buffer changes.
+ */
 
 static GtkTextBuffer *
 get_buffer (GtkSourceCompletionContext *context)
@@ -113,26 +115,22 @@ get_buffer (GtkSourceCompletionContext *context)
 static void
 gtk_source_completion_context_dispose (GObject *object)
 {
-       GtkSourceCompletionContext *context;
-       GtkTextBuffer *buffer;
-
-       context = GTK_SOURCE_COMPLETION_CONTEXT (object);
-       buffer = get_buffer (context);
+       GtkSourceCompletionContext *context = GTK_SOURCE_COMPLETION_CONTEXT (object);
 
-       if (context->priv->mark_set_id != 0)
+       if (context->priv->mark != NULL)
        {
-               g_signal_handler_disconnect (buffer, context->priv->mark_set_id);
-               context->priv->mark_set_id = 0;
-       }
+               GtkTextBuffer *buffer = gtk_text_mark_get_buffer (context->priv->mark);
 
-       g_clear_object (&context->priv->completion);
+               if (buffer != NULL)
+               {
+                       gtk_text_buffer_delete_mark (buffer, context->priv->mark);
+               }
 
-       if (context->priv->mark != NULL)
-       {
-               gtk_text_buffer_delete_mark (buffer, context->priv->mark);
                context->priv->mark = NULL;
        }
 
+       g_clear_object (&context->priv->completion);
+
        G_OBJECT_CLASS (gtk_source_completion_context_parent_class)->dispose (object);
 }
 
@@ -225,10 +223,12 @@ gtk_source_completion_context_constructed (GObject *object)
        /* we need to connect after the completion property is set */
        context = GTK_SOURCE_COMPLETION_CONTEXT (object);
        buffer = get_buffer (context);
-       context->priv->mark_set_id = g_signal_connect (buffer,
-                                                      "mark-set",
-                                                      G_CALLBACK (buffer_mark_set_cb),
-                                                      context);
+
+       g_signal_connect_object (buffer,
+                                "mark-set",
+                                G_CALLBACK (buffer_mark_set_cb),
+                                context,
+                                0);
 
        G_OBJECT_CLASS (gtk_source_completion_context_parent_class)->constructed (object);
 }