borg/src/borg/testsuite/chunker.py

46 lines
3.1 KiB
Python

from io import BytesIO
from ..algorithms.chunker import Chunker, buzhash, buzhash_update
from ..constants import * # NOQA
from . import BaseTestCase
# Note: these tests are part of the self test, do not use or import py.test functionality here.
# See borg.selftest for details. If you add/remove test methods, update SELFTEST_COUNT
class ChunkerTestCase(BaseTestCase):
def test_chunkify(self):
data = b'0' * int(1.5 * (1 << CHUNK_MAX_EXP)) + b'Y'
parts = [bytes(c) for c in Chunker(0, 1, CHUNK_MAX_EXP, 2, 2).chunkify(BytesIO(data))]
self.assert_equal(len(parts), 2)
self.assert_equal(b''.join(parts), data)
self.assert_equal([bytes(c) for c in Chunker(0, 1, CHUNK_MAX_EXP, 2, 2).chunkify(BytesIO(b''))], [])
self.assert_equal([bytes(c) for c in Chunker(0, 1, CHUNK_MAX_EXP, 2, 2).chunkify(BytesIO(b'foobarboobaz' * 3))], [b'fooba', b'rboobaz', b'fooba', b'rboobaz', b'fooba', b'rboobaz'])
self.assert_equal([bytes(c) for c in Chunker(1, 1, CHUNK_MAX_EXP, 2, 2).chunkify(BytesIO(b'foobarboobaz' * 3))], [b'fo', b'obarb', b'oob', b'azf', b'oobarb', b'oob', b'azf', b'oobarb', b'oobaz'])
self.assert_equal([bytes(c) for c in Chunker(2, 1, CHUNK_MAX_EXP, 2, 2).chunkify(BytesIO(b'foobarboobaz' * 3))], [b'foob', b'ar', b'boobazfoob', b'ar', b'boobazfoob', b'ar', b'boobaz'])
self.assert_equal([bytes(c) for c in Chunker(0, 2, CHUNK_MAX_EXP, 2, 3).chunkify(BytesIO(b'foobarboobaz' * 3))], [b'foobarboobaz' * 3])
self.assert_equal([bytes(c) for c in Chunker(1, 2, CHUNK_MAX_EXP, 2, 3).chunkify(BytesIO(b'foobarboobaz' * 3))], [b'foobar', b'boobazfo', b'obar', b'boobazfo', b'obar', b'boobaz'])
self.assert_equal([bytes(c) for c in Chunker(2, 2, CHUNK_MAX_EXP, 2, 3).chunkify(BytesIO(b'foobarboobaz' * 3))], [b'foob', b'arboobaz', b'foob', b'arboobaz', b'foob', b'arboobaz'])
self.assert_equal([bytes(c) for c in Chunker(0, 3, CHUNK_MAX_EXP, 2, 3).chunkify(BytesIO(b'foobarboobaz' * 3))], [b'foobarboobaz' * 3])
self.assert_equal([bytes(c) for c in Chunker(1, 3, CHUNK_MAX_EXP, 2, 3).chunkify(BytesIO(b'foobarboobaz' * 3))], [b'foobarbo', b'obazfoobar', b'boobazfo', b'obarboobaz'])
self.assert_equal([bytes(c) for c in Chunker(2, 3, CHUNK_MAX_EXP, 2, 3).chunkify(BytesIO(b'foobarboobaz' * 3))], [b'foobarboobaz', b'foobarboobaz', b'foobarboobaz'])
def test_buzhash(self):
self.assert_equal(buzhash(b'abcdefghijklmnop', 0), 3795437769)
self.assert_equal(buzhash(b'abcdefghijklmnop', 1), 3795400502)
self.assert_equal(buzhash(b'abcdefghijklmnop', 1), buzhash_update(buzhash(b'Xabcdefghijklmno', 1), ord('X'), ord('p'), 16, 1))
# Test with more than 31 bytes to make sure our barrel_shift macro works correctly
self.assert_equal(buzhash(b'abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz', 0), 566521248)
def test_small_reads(self):
class SmallReadFile:
input = b'a' * (20 + 1)
def read(self, nbytes):
self.input = self.input[:-1]
return self.input[:1]
reconstructed = b''.join(Chunker(0, *CHUNKER_PARAMS).chunkify(SmallReadFile()))
assert reconstructed == b'a' * 20