def test_diameter_changeable_but_area_not(self):
     circle = Circle(2)
     self.assertEqual(circle.diameter, 4)
     self.assertEqual(circle.area, math.pi * 4)
     circle.diameter = 3
     self.assertEqual(circle.radius, 1.5)
     with self.assertRaises(AttributeError):
         circle.area = 3
 def test_radius(self):
     circle = Circle(5)
     self.assertEqual(circle.radius, 5)
 def test_no_negative_radius(self):
     circle = Circle(2)
     with self.assertRaises(ValueError) as context:
         circle.radius = -10
     self.assertEqual(str(context.exception), "Radius cannot be negative")
 def test_diameter_and_area_change_based_on_radius(self):
     circle = Circle(2)
     self.assertEqual(circle.diameter, 4)
     circle.radius = 3
     self.assertEqual(circle.diameter, 6)
     self.assertEqual(circle.area, math.pi * 9)
 def test_string_representation(self):
     circle = Circle(2)
     self.assertEqual(str(circle), 'Circle(2)')
     self.assertEqual(repr(circle), 'Circle(2)')
     circle.radius = 1
     self.assertEqual(repr(circle), 'Circle(1)')
 def test_area(self):
     circle = Circle(2)
     self.assertEqual(circle.area, math.pi * 4)
     circle = Circle(1)
     self.assertEqual(circle.area, math.pi)
 def test_diameter(self):
     circle = Circle(2)
     self.assertEqual(circle.diameter, 4)
 def test_default_radius(self):
     circle = Circle()
     self.assertEqual(circle.radius, 1)