curds: Implement functions for finding and allocating nodes

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

curds/playlist/node.py

@@ -40,9 +40,19 @@ class PlaylistNode:
     def __str__(self):
         return f"<big>{self.name}</big>"
 
+    def alloc_node(self, name):
+        return PlaylistNode(name)
+
     def append_child(self, child):
         return self.__insert_node__(child, len(self.children))
 
+    def find_node(self, name):
+        node = self.lookup(name)
+        if node == None:
+            node = self.alloc_node(name)
+            self.insert_child(node)
+        return node
+
     def get_node(self, path):
         if len(path) == 1:
             return self.nth_child(path[0])

curds/playlist/test_node.py

@@ -35,6 +35,13 @@ class TestPlaylistNode(unittest.TestCase):
         self.assertFalse(b < a)
         self.assertFalse(a < a)
 
+    def test_node_alloc(self):
+        root = node.PlaylistNode()
+        a    = root.alloc_node("A")
+        self.assertIsInstance(a, node.PlaylistNode)
+        self.assertEqual(a.name, "A")
+        self.assertEqual(a.icon, "")
+
     def test_node_append_child(self):
         notify.register("node-inserted", self.on_insert_node)
         self.cb_insert = None
@@ -140,6 +147,19 @@ class TestPlaylistNode(unittest.TestCase):
         self.assertIsNone(root.lookup_byid(id(c)))
         self.assertIsNone(root.lookup_byid(42))
 
+    def test_node_find(self):
+        root = node.PlaylistNode()
+        b    = root.find_node("B")
+        self.assertIsInstance(b, node.PlaylistNode)
+        self.assertEqual(b.name, "B")
+
+        a    = root.find_node("A")
+        self.assertIsInstance(a, node.PlaylistNode)
+        self.assertEqual(a.name, "A")
+
+        self.assertEqual(root.find_node("A"), a)
+        self.assertEqual(root.find_node("B"), b)
+
     def test_node_nth_child(self):
         root = node.PlaylistNode()
         a = node.PlaylistNode("a")