Improving Surface.get_rect and Surface.get_frect tests

[Matiiss]

Both the tests for pygame.Surface.get_rect and pygame.Surface.get_frect lack a couple of tests for some of the main features of these methods. Using keyword arguments to set rect values. As well as checking whether appropriate exceptions are raised.

For both methods test:

• whether using correct keyword argument(s) sets the appropriate rect attribute
• that when using multiple different kwargs, only the last one is applied
• that appropriate exceptions are raised when using kwarg names that don't match rect attributes (like centre instead of center)

For Rect:

• add the difference between current get_rect and get_frect tests to get_rect (test position and instance type)

pygame-ce/test/surface_test.py

Lines 587 to 605 in aff289d

	def test_get_rect(self):
	"""Ensure a surface's rect can be retrieved."""
	size = (16, 16)
	surf = pygame.Surface(size)
	rect = surf.get_rect()
	self.assertEqual(rect.size, size)
	########################################################################
	def test_get_frect(self):
	"""Ensure a surface's frect can be retrieved."""
	size = (16.0, 16.0)
	surf = pygame.Surface(size)
	frect = surf.get_frect()
	self.assertEqual(frect.topleft, (0.0, 0.0))
	self.assertEqual(frect.size, size)
	self.assertIsInstance(frect, pygame.FRect)