def testReadBytes(self): s = 'abcd' # Also test going past the total stream length. for i in range(len(s) + 10): stream = input_stream.InputStream(s) self.assertEqual(s[:i], stream.ReadBytes(i)) self.assertEqual(min(i, len(s)), stream.Position()) stream = input_stream.InputStream(s) self.assertRaises(message.DecodeError, stream.ReadBytes, -1)
def testReadVarUInt64Failure(self): self.EnsureFailureOnEmptyStream(input_stream.InputStream.ReadVarUInt64) # Try and fail to read something with the mythical 64th bit set. s = '\x80\x80\x80\x80\x80\x80\x80\x80\x80\x02' stream = input_stream.InputStream(s) self.assertRaises(message.DecodeError, stream.ReadVarUInt64) # Try and fail to read something that looks like # a varint with more than 10 bytes. s = '\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\x00' stream = input_stream.InputStream(s) self.assertRaises(message.DecodeError, stream.ReadVarUInt64)
def testReadVarUInt32Failure(self): self.EnsureFailureOnEmptyStream(input_stream.InputStream.ReadVarUInt32) # Try and fail to read UINT32_MAX + 1 s = '\x80\x80\x80\x80\x10' stream = input_stream.InputStream(s) self.assertRaises(message.DecodeError, stream.ReadVarUInt32) # Try and fail to read something that looks like # a varint with more than 10 bytes. s = '\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\x00' stream = input_stream.InputStream(s) self.assertRaises(message.DecodeError, stream.ReadVarUInt32)
def EnsureFailureOnEmptyStream(self, input_stream_method): """Helper for integer-parsing tests below. Ensures that the given InputStream method raises a DecodeError if called on a stream with no bytes remaining. """ stream = input_stream.InputStream('') self.assertRaises(message.DecodeError, input_stream_method, stream)
def __init__(self, s): """Initializes the decoder to read from s. Args: s: An immutable sequence of bytes, which must be accessible via the Python buffer() primitive (i.e., buffer(s)). """ self._stream = input_stream.InputStream(s)
def testPosition(self): stream = input_stream.InputStream('abcd') self.assertEqual(0, stream.Position()) self.assertEqual(0, stream.Position()) # No side-effects. stream.ReadBytes(1) self.assertEqual(1, stream.Position()) stream.ReadBytes(1) self.assertEqual(2, stream.Position()) stream.ReadBytes(10) self.assertEqual(4, stream.Position()) # Can't go past end of stream.
def testSkipBytes(self): stream = input_stream.InputStream('') # Skipping bytes when at the end of stream # should have no effect. stream.SkipBytes(0) stream.SkipBytes(1) stream.SkipBytes(2) self.assertTrue(stream.EndOfStream()) self.assertEqual(0, stream.Position()) # Try skipping within a stream. stream = input_stream.InputStream('abcd') self.assertEqual(0, stream.Position()) stream.SkipBytes(1) self.assertEqual(1, stream.Position()) stream.SkipBytes(10) # Can't skip past the end. self.assertEqual(4, stream.Position()) # Ensure that a negative skip raises an exception. stream = input_stream.InputStream('abcd') stream.SkipBytes(1) self.assertRaises(message.DecodeError, stream.SkipBytes, -1)
def testGetSubBuffer(self): stream = input_stream.InputStream('abcd') # Try leaving out the size. self.assertEqual('abcd', str(stream.GetSubBuffer())) stream.SkipBytes(1) # GetSubBuffer() always starts at current size. self.assertEqual('bcd', str(stream.GetSubBuffer())) # Try 0-size. self.assertEqual('', str(stream.GetSubBuffer(0))) # Negative sizes should raise an error. self.assertRaises(message.DecodeError, stream.GetSubBuffer, -1) # Positive sizes should work as expected. self.assertEqual('b', str(stream.GetSubBuffer(1))) self.assertEqual('bc', str(stream.GetSubBuffer(2))) # Sizes longer than remaining bytes in the buffer should # return the whole remaining buffer. self.assertEqual('bcd', str(stream.GetSubBuffer(1000)))
def ReadVarintSuccessTestHelper(self, varints_and_ints, read_method): """Helper for tests below that test successful reads of various varints. Args: varints_and_ints: Iterable of (str, integer) pairs, where the string gives the wire encoding and the integer gives the value we expect to be returned by the read_method upon encountering this string. read_method: Unbound InputStream method that is capable of reading the encoded strings provided in the first elements of varints_and_ints. """ s = ''.join(s for s, i in varints_and_ints) stream = input_stream.InputStream(s) expected_pos = 0 self.assertEqual(expected_pos, stream.Position()) for s, expected_int in varints_and_ints: self.assertEqual(expected_int, read_method(stream)) expected_pos += len(s) self.assertEqual(expected_pos, stream.Position())
def testReadLittleEndian64(self): self.EnsureFailureOnEmptyStream(input_stream.InputStream.ReadLittleEndian64) s = '' # Read 0. s += '\x00\x00\x00\x00\x00\x00\x00\x00' # Read 1. s += '\x01\x00\x00\x00\x00\x00\x00\x00' # Read a bunch of different bytes. s += '\x01\x02\x03\x04\x05\x06\x07\x08' # Read max unsigned 64-bit int. s += '\xff\xff\xff\xff\xff\xff\xff\xff' # Try a read with fewer than 8 bytes left in the stream. s += '\x00\x00\x00' stream = input_stream.InputStream(s) self.assertEqual(0, stream.ReadLittleEndian64()) self.assertEqual(8, stream.Position()) self.assertEqual(1, stream.ReadLittleEndian64()) self.assertEqual(16, stream.Position()) self.assertEqual(0x0807060504030201, stream.ReadLittleEndian64()) self.assertEqual(24, stream.Position()) self.assertEqual(wire_format.UINT64_MAX, stream.ReadLittleEndian64()) self.assertEqual(32, stream.Position()) self.assertRaises(message.DecodeError, stream.ReadLittleEndian64)
def testEndOfStream(self): stream = input_stream.InputStream('abcd') self.assertFalse(stream.EndOfStream()) self.assertEqual('abcd', stream.ReadBytes(10)) self.assertTrue(stream.EndOfStream())