Mar 2, 2026 · Mar 2, 2026 · Mar 2, 2026
diff --git a/Lib/test/test_turtle.py b/Lib/test/test_turtle.py
        self.assertRaises(turtle.TurtleGraphicsError, self.turtle.dot, 0, (0, 257, 0))
        self.assertRaises(turtle.TurtleGraphicsError, self.turtle.dot, 0, 0, 257, 0)

    def test_clone_clear_does_not_delete_source_items(self):
        screen = self.turtle.screen
        screen._delete.reset_mock()
        screen._createline.side_effect = lambda: object()

        self.turtle.circle(20)
        clone = self.turtle.clone()
        source_items = set(self.turtle.items)

        clone.forward(50)
        clone.clear()

        deleted_items = {call.args[0] for call in screen._delete.call_args_list}
        self.assertFalse(source_items & deleted_items)

 class TestModuleLevel(unittest.TestCase):
    def test_all_signatures(self):
        import inspect
diff --git a/Lib/turtle.py b/Lib/turtle.py
            q.turtle._item = [screen._createpoly() for item in
                              screen._shapes[self.turtle.shapeIndex]._data]
        q.currentLineItem = screen._createline()
        q.currentLine = [q._position] if q._drawing else []
        q.items = [q.currentLineItem]
        q._update()
        return q

diff --git a/Misc/ACKS b/Misc/ACKS
 Michael P. Reilly
 Bernhard Reiter
 Steven Reiz
 Yuxing Ren
 Roeland Rengelink
 Antoine Reversat
 Flávio Ribeiro
Original file line number	Diff line number	Diff line change
Expand Up		@@ -671,6 +671,21 @@ def test_dot_signature(self):
		self.assertRaises(turtle.TurtleGraphicsError, self.turtle.dot, 0, (0, 257, 0))
		self.assertRaises(turtle.TurtleGraphicsError, self.turtle.dot, 0, 0, 257, 0)

		def test_clone_clear_does_not_delete_source_items(self):
		screen = self.turtle.screen
		screen._delete.reset_mock()
		screen._createline.side_effect = lambda: object()

		self.turtle.circle(20)
		clone = self.turtle.clone()
		source_items = set(self.turtle.items)

		clone.forward(50)
		clone.clear()

		deleted_items = {call.args[0] for call in screen._delete.call_args_list}
		self.assertFalse(source_items & deleted_items)

Comment on lines +674 to +688 Copy link CopilotAIMar 2, 2026 Choose a reason for hiding this comment The reason will be displayed to describe this comment to others.Learn more. This test only asserts that`clone.clear()` doesn’t delete items from`self.turtle.items`, but the bug class here also involves other clone-owned collections (notably`stampItems` and`undobuffer`) that can still contain source-owned canvas ids after`deepcopy()`. Extending the test to cover stamps (e.g., source`stamp()` then`clone.clear()`/`clearstamps()`) and undo behavior (e.g.,`clone.undo()` doesn’t touch source drawings) would prevent regressions once`clone()` is updated to reinitialize those fields too. Copilot uses AI. Check for mistakes.
		class TestModuleLevel(unittest.TestCase):
		def test_all_signatures(self):
		import inspect
Expand Down