rind: Node model cleanups

- Listen for the "first-child" notification rather than "node-inserted"
- Use the walrus operator in more places to tidy up the code
- Use the playlist_iter() function to get iterators directly

Signed-off-by: Anna Schumaker <Anna@NoWheyCreamery.com>

rind/node/model.py

@@ -57,25 +57,22 @@ class NodeTreeModel(GObject.GObject, Gtk.TreeModel):
         return self.iter_n_children(iter) > 0
 
     def do_iter_n_children(self, iter):
-        plist = self.iter_playlist(iter)
-        if plist:
+        if (plist := self.iter_playlist(iter)):
             return plist.n_children()
         return 0
 
     def do_iter_nth_child(self, iter, n):
-        plist = self.iter_playlist(iter)
-        if plist == None or n >= plist.n_children():
-            return (False, None)
-        child = plist.nth_child(n)
-        return (True, self.playlist_iter(child))
+        if (plist := self.iter_playlist(iter)) != None:
+            if (child := plist.nth_child(n)) != None:
+                return (True, self.playlist_iter(child))
+        return (False, None)
 
     def do_iter_next(self, iter):
-        plist = self.iter_playlist(iter)
-        next  = plist.next_child() if plist != None else None
-        if next == None:
-            return (False, None)
-        iter.user_data = id(next)
-        return (True, iter)
+        if (plist := self.iter_playlist(iter)) != None:
+            if (next := plist.next_child()) != None:
+                iter.user_data = id(next)
+                return (True, iter)
+        return (False, None)
 
     def do_iter_parent(self, child):
         plist = self.iter_playlist(child)
@@ -89,15 +86,14 @@ class NodeTreeModel(GObject.GObject, Gtk.TreeModel):
             return curds.playlist.Root.lookup_byid(iter.user_data)
         return curds.playlist.Root
 
+    def on_first_child(self, parent, path):
+        if parent.parent != None:
+            self.row_has_child_toggled(Gtk.TreePath(path), self.playlist_iter(parent))
+
     def on_playlist_changed(self, plist):
         if plist.parent:
             path = Gtk.TreePath(plist.get_path())
-            self.row_changed(path, self.get_iter(path))
-
-    def on_node_inserted(self, plist, index):
-        if not plist.parent.n_children() > 1:
-            path = Gtk.TreePath(plist.parent.get_path())
-            self.row_has_child_toggled(path, self.get_iter(path))
+            self.row_changed(path, self.playlist_iter(plist))
 
     def playlist_iter(self, plist):
         if plist == None or plist.parent == None:
@@ -107,5 +103,5 @@ class NodeTreeModel(GObject.GObject, Gtk.TreeModel):
         return iter
 
     def reset(self):
-        curds.notify.register("node-inserted",    self.on_node_inserted, idle=True)
+        curds.notify.register("first-child",      self.on_first_child, idle=True)
         curds.notify.register("playlist-changed", self.on_playlist_changed, idle=True)

rind/node/test_model.py

@@ -23,7 +23,7 @@ class TestNodeTreeModel(unittest.TestCase):
         curds.trak.lookup(os.path.join(test_album2, "01 - Test Track 01.ogg"))
 
     def tearDown(self):
-        curds.notify.cancel("node-inserted",    self.model.on_node_inserted)
+        curds.notify.cancel("first-child",      self.model.on_first_child)
         curds.notify.cancel("playlist-changed", self.model.on_playlist_changed)
 
     def tearDownClass():