[gnome-builder] todo: remove previous entries when saving buffer

[Christian Hergert <chergert src gnome org>]

commit 6817c002a0352d35a72e34e6b0b32a608e4c8525
Author: Christian Hergert <chergert redhat com>
Date:   Tue Jan 26 04:43:53 2016 +0100

    todo: remove previous entries when saving buffer
    
    When we save a file, walk through the list of items in the treeview.
    Remove any file that matches the GFile that was just saved.
    
    Afterwards, parse TODO items as normal, re-populating the treeview.
    
    https://bugzilla.gnome.org/review?bug=760728

 plugins/todo/todo_plugin/__init__.py |   15 ++++++++++++++-
 1 files changed, 14 insertions(+), 1 deletions(-)
---
diff --git a/plugins/todo/todo_plugin/__init__.py b/plugins/todo/todo_plugin/__init__.py
index f091e41..672b533 100644
--- a/plugins/todo/todo_plugin/__init__.py
+++ b/plugins/todo/todo_plugin/__init__.py
@@ -72,7 +72,8 @@ class TodoWorkbenchAddin(GObject.Object, Ide.WorkbenchAddin):
         # Get the underline GFile
         file = buf.get_file().get_file()
 
-        # XXX: Clear existing items from this file
+        # Clear any existing items matching this file
+        self.panel.clear_file(file)
 
         # Mine the file for todo items
         self.mine(file)
@@ -203,6 +204,18 @@ class TodoPanel(Gtk.Bin):
         iter = self.model.append()
         self.model.set_value(iter, 0, item)
 
+    def clear_file(self, file):
+        iter = self.model.get_iter_first()
+        while iter != None:
+            todo_item, = self.model.get(iter, 0)
+            if todo_item.props.file.equal(file):
+                # If remove() returns false, it was the last item in the store.
+                # Otherwise, iter was advanced for us.
+                if not self.model.remove(iter):
+                    break
+                continue
+            iter = self.model.iter_next(iter)
+
     def on_query_tooltip(self, treeview, x, y, keyboard, tooltip):
         x, y = treeview.convert_widget_to_bin_window_coords(x, y)
         try: