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_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_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)')