def test_set_content_empty_tape_left_left_right():
tape = Tape('B', ['a', 'b', 'X', 'B'], [])
tape.move_left()
tape.move_left()
tape.move_right()
tape.set_content('a')
assert tape.get_content() == 'a'
assert tape.position == 1
assert tape.content == ['B', 'a']
def test_get_content_of_empty_tape():
tape = Tape('B', ['a', 'b', 'X', 'B'], [])
assert tape.get_content() == 'B'
def test_set_content_empty_tape():
tape = Tape('B', ['a', 'b', 'X', 'B'], [])
tape.set_content('a')
assert tape.get_content() == 'a'
assert tape.content == ['a']
assert tape.position == 0
def test_move_head_right_left():
tape = Tape('B', ['a', 'b', 'X', 'B'], ['a', 'b'])
tape.move_head('R')
tape.move_head('L')
assert tape.get_content() == 'a'
assert tape.position == 0
def test_move_head_stay():
tape = Tape('B', ['a', 'b', 'X', 'B'], ['a', 'b'])
tape.move_head('S')
assert tape.get_content() == 'a'
assert tape.content == ['a', 'b']
assert tape.position == 0
def test_get_content_of_non_empty_tape_at_end_with_head_moved_to_right():
tape = Tape('B', ['a', 'b', 'X', 'B'], ['a', 'b'])
tape.move_right()
tape.move_right()
assert tape.get_content() == 'B'
def test_get_content_of_non_empty_tape_at_start_with_head_moved_to_left():
tape = Tape('B', ['a', 'b', 'X', 'B'], ['a', 'b'])
tape.move_left()
assert tape.get_content() == 'B'
assert tape.position == 0