import numpy as np
import unittest

from enable.kiva_graphics_context import GraphicsContext


class TestGCErrors(unittest.TestCase):
    """Test some cases where a ValueError should be raised."""

    def test_bad_image_size(self):
        arr = np.array([[1, 2], [3, 4]], dtype=np.uint8)
        gc = GraphicsContext((50, 50))
        # The draw_image methods expects its first argument
        # to be a 3D whose last dimension has lenght 3 or 4.
        # Passing in arr should raise a value error.
        self.assertRaises(ValueError, gc.draw_image, arr)

        # Pass in a 3D array, but with an invalid size in the last dimension.
        self.assertRaises(ValueError, gc.draw_image, arr.reshape(2, 2, 1))


if __name__ == "__main__":
    unittest.main()