[3.13] gh-138772: Add tests for Turtle.dot() signature (GH-138773)

Lib/test/test_turtle.py

@@ -1,5 +1,6 @@
 import pickle
 import unittest
+import unittest.mock
 from test import support
 from test.support import import_helper
 from test.support import os_helper
@@ -50,6 +51,34 @@
 """
 
 
+def patch_screen():
+ """Patch turtle._Screen for testing without a display.
+
+ We must patch the _Screen class itself instead of the _Screen
+ instance because instantiating it requires a display.
+ """
+ # Create a mock screen that delegates color validation to the real TurtleScreen methods
+ mock_screen = unittest.mock.MagicMock()
+ mock_screen.__class__ = turtle._Screen
+ mock_screen.mode.return_value = "standard"
+ mock_screen._colormode = 1.0
+
+ def mock_iscolorstring(color):
+ valid_colors ={'red', 'green', 'blue', 'black', 'white', 'yellow',
+ 'orange', 'purple', 'pink', 'brown', 'gray', 'grey',
+ 'cyan', 'magenta'}
+
+ return color in valid_colors or (isinstance(color, str) and color.startswith('#'))
+
+ mock_screen._iscolorstring = mock_iscolorstring
+ mock_screen._colorstr = turtle._Screen._colorstr.__get__(mock_screen)
+
+ return unittest.mock.patch(
+ "turtle._Screen.__new__",
+ return_value=mock_screen
+ )
+
+
 class TurtleConfigTest(unittest.TestCase):
 
  def get_cfg_file(self, cfg_str):
@@ -461,6 +490,38 @@ def test_teleport(self):
  self.assertTrue(tpen.isdown())
 
 
+class TestTurtle(unittest.TestCase):
+ def setUp(self):
+ with patch_screen():
+ self.turtle = turtle.Turtle()
+
+ # Reset the Screen singleton to avoid reference leaks
+ self.addCleanup(setattr, turtle.Turtle, '_screen', None)
+
+ def test_dot_signature(self):
+ self.turtle.dot()
+ self.turtle.dot(10)
+ self.turtle.dot(size=10)
+ self.turtle.dot((0, 0, 0))
+ self.turtle.dot(size=(0, 0, 0))
+ self.turtle.dot("blue")
+ self.turtle.dot("")
+ self.turtle.dot(size="blue")
+ self.turtle.dot(20, "blue")
+ self.turtle.dot(20, "blue")
+ self.turtle.dot(20, (0, 0, 0))
+ self.turtle.dot(20, 0, 0, 0)
+ with self.assertRaises(TypeError):
+ self.turtle.dot(color="blue")
+ self.assertRaises(turtle.TurtleGraphicsError, self.turtle.dot, "_not_a_color_")
+ self.assertRaises(turtle.TurtleGraphicsError, self.turtle.dot, 0, (0, 0, 0, 0))
+ self.assertRaises(turtle.TurtleGraphicsError, self.turtle.dot, 0, 0, 0, 0, 0)
+ self.assertRaises(turtle.TurtleGraphicsError, self.turtle.dot, 0, (-1, 0, 0))
+ self.assertRaises(turtle.TurtleGraphicsError, self.turtle.dot, 0, -1, 0, 0)
+ self.assertRaises(turtle.TurtleGraphicsError, self.turtle.dot, 0, (0, 257, 0))
+ self.assertRaises(turtle.TurtleGraphicsError, self.turtle.dot, 0, 0, 257, 0)
+
+
 class TestModuleLevel(unittest.TestCase):
  def test_all_signatures(self):
  import inspect