stream: in v3, skip the "size" fast path if the entries as some unknown size
We are about to prefetch size during the lock less in the v3 case. So we need to
avoid trying to use that prefetched size when it is not available.
See next changeset for the motivation.
import io
import unittest
from mercurial import util
class CappedReaderTests(unittest.TestCase):
def testreadfull(self):
source = io.BytesIO(b'x' * 100)
reader = util.cappedreader(source, 10)
res = reader.read(10)
self.assertEqual(res, b'x' * 10)
self.assertEqual(source.tell(), 10)
source.seek(0)
reader = util.cappedreader(source, 15)
res = reader.read(16)
self.assertEqual(res, b'x' * 15)
self.assertEqual(source.tell(), 15)
source.seek(0)
reader = util.cappedreader(source, 100)
res = reader.read(100)
self.assertEqual(res, b'x' * 100)
self.assertEqual(source.tell(), 100)
source.seek(0)
reader = util.cappedreader(source, 50)
res = reader.read()
self.assertEqual(res, b'x' * 50)
self.assertEqual(source.tell(), 50)
source.seek(0)
def testreadnegative(self):
source = io.BytesIO(b'x' * 100)
reader = util.cappedreader(source, 20)
res = reader.read(-1)
self.assertEqual(res, b'x' * 20)
self.assertEqual(source.tell(), 20)
source.seek(0)
reader = util.cappedreader(source, 100)
res = reader.read(-1)
self.assertEqual(res, b'x' * 100)
self.assertEqual(source.tell(), 100)
source.seek(0)
def testreadmultiple(self):
source = io.BytesIO(b'x' * 100)
reader = util.cappedreader(source, 10)
for i in range(10):
res = reader.read(1)
self.assertEqual(res, b'x')
self.assertEqual(source.tell(), i + 1)
self.assertEqual(source.tell(), 10)
res = reader.read(1)
self.assertEqual(res, b'')
self.assertEqual(source.tell(), 10)
source.seek(0)
reader = util.cappedreader(source, 45)
for i in range(4):
res = reader.read(10)
self.assertEqual(res, b'x' * 10)
self.assertEqual(source.tell(), (i + 1) * 10)
res = reader.read(10)
self.assertEqual(res, b'x' * 5)
self.assertEqual(source.tell(), 45)
def readlimitpasteof(self):
source = io.BytesIO(b'x' * 100)
reader = util.cappedreader(source, 1024)
res = reader.read(1000)
self.assertEqual(res, b'x' * 100)
self.assertEqual(source.tell(), 100)
res = reader.read(1000)
self.assertEqual(res, b'')
self.assertEqual(source.tell(), 100)
if __name__ == '__main__':
import silenttestrunner
silenttestrunner.main(__name__)