def test_out_of_range_raises(self):
"""Test than an invalid `index` value raises an exception."""
msg = r"'index' must be between 0 and 7, inclusive"
with pytest.raises(ValueError, match=msg):
get_bit(b'\x00', -1)
with pytest.raises(ValueError, match=msg):
get_bit(b'\x00', 8)
def test_multiple_bytes_inverse(self):
"""Test that only the bit value from the first byte is returned"""
ref_bytes = [
b'\xfe\x00', b'\xfd\x00', b'\xfb\x00', b'\xf7\x00', b'\xef\x00',
b'\xdf\x00', b'\xbf\x00', b'\x7f\x00'
]
for ii in range(0, 8, -1):
assert 0 == get_bit(ref_bytes[ii], ii)
def test_multiple_bytes(self):
"""Test that only the bit value from the first byte is returned"""
ref_bytes = [
b'\x01\xff', b'\x02\xff', b'\x04\xff', b'\x08\xff', b'\x10\xff',
b'\x20\xff', b'\x40\xff', b'\x80\xff'
]
for ii in range(0, 8, -1):
assert 1 == get_bit(ref_bytes[ii], ii)
def test_index_correct_inverse(self):
"""Test that the `index` returns the correct bit = 0."""
ref_bytes = [
b'\xfe', b'\xfd', b'\xfb', b'\xf7', b'\xef', b'\xdf', b'\xbf',
b'\x7f'
]
for ii in range(0, 8, -1):
assert 0 == get_bit(ref_bytes[ii], ii)
def test_index_correct(self):
"""Test that the `index` returns the correct bit = 1."""
ref_bytes = [
b'\x01', b'\x02', b'\x04', b'\x08', b'\x10', b'\x20', b'\x40',
b'\x80'
]
for ii in range(0, 8, -1):
assert 1 == get_bit(ref_bytes[ii], ii)
def test_empty_byte_raises(self):
"""Test that an empty `byte` value raises an exception."""
msg = r"ord\(\) expected a character"
with pytest.raises(TypeError, match=msg):
get_bit(b'', 0)