def read(self, reader: BitStreamReader, size: int = 0) -> None:
"""
Reads array from the bit stream.
:param reader: Bit stream from which to read.
:param size: Number of elements to read or None in case of implicit or auto arrays.
:raises PythonRuntimeException: If the array does not have elements with constant bit size.
"""
self._raw_array.clear()
if self._is_implicit:
if not self._array_traits.HAS_BITSIZEOF_CONSTANT:
raise PythonRuntimeException(
"Array: Implicit array elements must have constant bit size!"
)
element_size = self._array_traits.bitsizeof()
remaining_bits = reader.buffer_bitsize - reader.bitposition
read_size = remaining_bits // element_size
for index in range(read_size):
self._raw_array.append(self._array_traits.read(reader, index))
else:
if self._is_auto:
read_size = reader.read_varsize()
else:
read_size = size
for index in range(read_size):
if self._check_offset_method is not None:
reader.alignto(8)
self._check_offset_method(index, reader.bitposition)
self._raw_array.append(self._array_traits.read(reader, index))
def test_alignto(self):
writer = BitStreamWriter()
writer.write_bits(5, 3)
writer.alignto(8)
self.assertEqual(8, writer.bitposition)
writer.write_bits(0, 1)
writer.alignto(16)
self.assertEqual(16, writer.bitposition)
writer.write_bits(0xaa, 9)
writer.alignto(32)
self.assertEqual(32, writer.bitposition)
writer.write_bits(0xaca, 13)
writer.alignto(64)
self.assertEqual(64, writer.bitposition)
writer.write_bits(0xcafe, 16)
reader = BitStreamReader(buffer=writer.byte_array)
self.assertEqual(5, reader.read_bits(3))
reader.alignto(8)
self.assertEqual(8, reader.bitposition)
self.assertEqual(0, reader.read_bits(1))
reader.alignto(16)
self.assertEqual(16, reader.bitposition)
self.assertEqual(0xaa, reader.read_bits(9))
reader.alignto(32)
self.assertEqual(32, reader.bitposition)
self.assertEqual(0xaca, reader.read_bits(13))
reader.alignto(64)
self.assertEqual(64, reader.bitposition)
self.assertEqual(0xcafe, reader.read_bits(16))
def test_alignto(self):
reader = BitStreamReader(bytes(1))
reader.alignto(1)
self.assertEqual(0, reader.bitposition)
reader.read_bits(1)
self.assertEqual(1, reader.bitposition)
reader.alignto(1)
self.assertEqual(1, reader.bitposition)
reader.alignto(4)
self.assertEqual(4, reader.bitposition)
