view tests/test-cappedreader.py @ 43147:54e943b28101

sidedatacopies: move various copies related function to the copies modules

We will need to access these logic form the copies module. So we move them from
their higher level module to the lower level `copies` module. We cannot use them
from their top level module as it would create cycles.

Differential Revision: https://phab.mercurial-scm.org/D6954

from __future__ import absolute_import, print_function

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__)