tests/test-cappedreader.py

merge: store ACTION_KEEP_ABSENT when we are keeping the file absent locally

If a file is not present on the local side, and it's unchanged between other
merge parent and ancestor, we don't use any action, neither we had a if-else
branch for that condition. This leads to bid-merge missing that there is a
such action possible which can be performed.

As test changes demonstrate, we now choose the locally deleted side instead
of choosing the remote one consistently. This is also wrong behavior which is
resulted because of missing possible action. It will be fixed in next patch.

This whole logic is not acurrate as we should prompt user on what to do
when this kind of criss-cross merge is in play.

Differential Revision: https://phab.mercurial-scm.org/D8940

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__)