Add public access (both get and set) to the label of a TreeNode

CHANGELOG.md

@@ -7,6 +7,10 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 ## [0.10.0] - Unreleased
 
+### Added
+
+- Added public `TreeNode` label access via `TreeNode.label` https://github.com/Textualize/textual/issues/1396
+
 ### Changed
 
 - `MouseScrollUp` and `MouseScrollDown` now inherit from `MouseEvent` and have attached modifier keys. https://github.com/Textualize/textual/pull/1458
@@ -29,8 +33,8 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 - Widget.render_line now returns a Strip
 - Fix for slow updates on Windows
-- Bumped Rich dependency 
-  
+- Bumped Rich dependency
+
 ## [0.8.2] - 2022-12-28
 
 ### Fixed

src/textual/widgets/_tree.py

@@ -71,7 +71,7 @@ def __init__(
         self._tree = tree
         self._parent = parent
         self._id = id
-        self._label = label
+        self._label = tree.process_label(label)
         self.data = data
         self._expanded = expanded
         self._children: list[TreeNode] = []
@@ -163,6 +163,15 @@ def toggle(self) -> None:
         self._updates += 1
         self._tree._invalidate()
 
+    @property
+    def label(self) -> TextType:
+        """TextType: The label for the node."""
+        return self._label
+
+    @label.setter
+    def label(self, new_label: TextType) -> None:
+        self.set_label(new_label)
+
     def set_label(self, label: TextType) -> None:
         """Set a new label for the node.
 

tests/tree/test_tree_node_label.py

@@ -0,0 +1,17 @@
+from textual.widgets import Tree, TreeNode
+from rich.text import Text
+
+def test_tree_node_label() -> None:
+    """It should be possible to modify a TreeNode's label."""
+    node = TreeNode(Tree[None]("Xenomorph Lifecycle"), None, 0, "Facehugger")
+    assert node.label == Text("Facehugger")
+    node.label = "Chestbuster"
+    assert node.label == Text("Chestbuster")
+
+def test_tree_node_label_via_tree() -> None:
+    """It should be possible to modify a TreeNode's label when created via a Tree."""
+    tree = Tree[None]("Xenomorph Lifecycle")
+    node = tree.root.add("Facehugger")
+    assert node.label == Text("Facehugger")
+    node.label = "Chestbuster"
+    assert node.label == Text("Chestbuster")