def test_add_photo():
canvas = Canvas()
canvas._width = 100
canvas._height = 150
canvas._photos = 5
canvas._map = {(0,0): "None", (0,50): "None", (0,100): "None", (0,150): "None",
(50,0): "None", (50,50): "None", (50,100): "None", (50,150): "None",
(100,0): "None", (100,50): "None", (100,100): "None", (100,150): "None"}
canvas.add_photo((0,20), (90, 80), "P_06")
assert canvas._photos == 6
assert canvas._map == {(0,0): "P_06", (0,50): "P_06", (0,100): "None", (0,150): "None",
(50,0): "P_06", (50,50): "P_06", (50,100): "None", (50,150): "None",
(100,0): "None", (100,50): "None", (100,100): "None", (100,150): "None"}
def test_photo_name():
canvas = Canvas()
canvas._photos = 5
result = canvas._gen_name()
assert result == "P_05"