view tests/test-cbor.py @ 40393:229d23cdb203

exchangev2: support fetching shallow files history

This commit teaches the exchangev2 client code to handle fetching shallow
files data.

Only shallow fetching of files data is supported: shallow fetching of
changeset and manifest data is explicitly not yet supported.

Previously, we would fetch file revisions for changesets that were received
by the current pull operation. In the new model, we calculate the set of
"relevant" changesets given the pull depth and only fetch files data for
those changesets.

We also teach the "filesdata" command invocation to vary parameters as needed.

The implementation here is far from complete or optimal. Subsequent pulls will
end up re-fetching a lot of files data. But the application of this data should
mostly be a no-op on the client, so it isn't a big deal.

Depending on the order file revisions are fetched in, revisions could get
inserted with the wrong revision number relationships. I think the best way
to deal with this is to remove revision numbers from storage and to either
dynamically derive them (by reconstructing a DAG from nodes/parents) or remove
revision numbers from the file storage interface completely.

A missing API that we'll likely want to write pretty soon is "ensure files
for revision(s) are present." We can kind of cajole exchangev2.pull() to do
this. But it isn't very efficient. For example, in simple cases like
widening the store to obtain data for a single revision, it is probably
more efficient to walk the manifest and find exactly which file revisions
are missing and to make explicit requests for just their data. In more
advanced cases, asking the server for all files data may be more efficient,
even though it requires sending data the client already has. There is tons
of room for future experimentation here. And TBH I'm not sure what the
final state will be.

Anyway, this commit gets us pretty close to being able to have shallow
and narrow checkouts with exchangev2/sqlite storage. Close enough that a
minimal extension should be able to provide fill in the gaps until the code
in core stabilizes and there is a user-facing way to trigger the
narrow/shallow bits from `hg clone` without also implying using of the
narrow extension...

Differential Revision: https://phab.mercurial-scm.org/D5169

from __future__ import absolute_import

import unittest

from mercurial.thirdparty import (
    cbor,
)
from mercurial.utils import (
    cborutil,
)

class TestCase(unittest.TestCase):
    if not getattr(unittest.TestCase, 'assertRaisesRegex', False):
        # Python 3.7 deprecates the regex*p* version, but 2.7 lacks
        # the regex version.
        assertRaisesRegex = (# camelcase-required
            unittest.TestCase.assertRaisesRegexp)

def loadit(it):
    return cbor.loads(b''.join(it))

class BytestringTests(TestCase):
    def testsimple(self):
        self.assertEqual(
            list(cborutil.streamencode(b'foobar')),
            [b'\x46', b'foobar'])

        self.assertEqual(
            loadit(cborutil.streamencode(b'foobar')),
            b'foobar')

        self.assertEqual(cborutil.decodeall(b'\x46foobar'),
                         [b'foobar'])

        self.assertEqual(cborutil.decodeall(b'\x46foobar\x45fizbi'),
                         [b'foobar', b'fizbi'])

    def testlong(self):
        source = b'x' * 1048576

        self.assertEqual(loadit(cborutil.streamencode(source)), source)

        encoded = b''.join(cborutil.streamencode(source))
        self.assertEqual(cborutil.decodeall(encoded), [source])

    def testfromiter(self):
        # This is the example from RFC 7049 Section 2.2.2.
        source = [b'\xaa\xbb\xcc\xdd', b'\xee\xff\x99']

        self.assertEqual(
            list(cborutil.streamencodebytestringfromiter(source)),
            [
                b'\x5f',
                b'\x44',
                b'\xaa\xbb\xcc\xdd',
                b'\x43',
                b'\xee\xff\x99',
                b'\xff',
            ])

        self.assertEqual(
            loadit(cborutil.streamencodebytestringfromiter(source)),
            b''.join(source))

        self.assertEqual(cborutil.decodeall(b'\x5f\x44\xaa\xbb\xcc\xdd'
                                            b'\x43\xee\xff\x99\xff'),
                         [b'\xaa\xbb\xcc\xdd', b'\xee\xff\x99', b''])

        for i, chunk in enumerate(
            cborutil.decodeall(b'\x5f\x44\xaa\xbb\xcc\xdd'
                               b'\x43\xee\xff\x99\xff')):
            self.assertIsInstance(chunk, cborutil.bytestringchunk)

            if i == 0:
                self.assertTrue(chunk.isfirst)
            else:
                self.assertFalse(chunk.isfirst)

            if i == 2:
                self.assertTrue(chunk.islast)
            else:
                self.assertFalse(chunk.islast)

    def testfromiterlarge(self):
        source = [b'a' * 16, b'b' * 128, b'c' * 1024, b'd' * 1048576]

        self.assertEqual(
            loadit(cborutil.streamencodebytestringfromiter(source)),
            b''.join(source))

    def testindefinite(self):
        source = b'\x00\x01\x02\x03' + b'\xff' * 16384

        it = cborutil.streamencodeindefinitebytestring(source, chunksize=2)

        self.assertEqual(next(it), b'\x5f')
        self.assertEqual(next(it), b'\x42')
        self.assertEqual(next(it), b'\x00\x01')
        self.assertEqual(next(it), b'\x42')
        self.assertEqual(next(it), b'\x02\x03')
        self.assertEqual(next(it), b'\x42')
        self.assertEqual(next(it), b'\xff\xff')

        dest = b''.join(cborutil.streamencodeindefinitebytestring(
            source, chunksize=42))
        self.assertEqual(cbor.loads(dest), source)

        self.assertEqual(b''.join(cborutil.decodeall(dest)), source)

        for chunk in cborutil.decodeall(dest):
            self.assertIsInstance(chunk, cborutil.bytestringchunk)
            self.assertIn(len(chunk), (0, 8, 42))

        encoded = b'\x5f\xff'
        b = cborutil.decodeall(encoded)
        self.assertEqual(b, [b''])
        self.assertTrue(b[0].isfirst)
        self.assertTrue(b[0].islast)

    def testdecodevariouslengths(self):
        for i in (0, 1, 22, 23, 24, 25, 254, 255, 256, 65534, 65535, 65536):
            source = b'x' * i
            encoded = b''.join(cborutil.streamencode(source))

            if len(source) < 24:
                hlen = 1
            elif len(source) < 256:
                hlen = 2
            elif len(source) < 65536:
                hlen = 3
            elif len(source) < 1048576:
                hlen = 5

            self.assertEqual(cborutil.decodeitem(encoded),
                             (True, source, hlen + len(source),
                              cborutil.SPECIAL_NONE))

    def testpartialdecode(self):
        encoded = b''.join(cborutil.streamencode(b'foobar'))

        self.assertEqual(cborutil.decodeitem(encoded[0:1]),
                         (False, None, -6, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:2]),
                         (False, None, -5, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:3]),
                         (False, None, -4, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:4]),
                         (False, None, -3, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:5]),
                         (False, None, -2, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:6]),
                         (False, None, -1, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:7]),
                         (True, b'foobar', 7, cborutil.SPECIAL_NONE))

    def testpartialdecodevariouslengths(self):
        lens = [
            2,
            3,
            10,
            23,
            24,
            25,
            31,
            100,
            254,
            255,
            256,
            257,
            16384,
            65534,
            65535,
            65536,
            65537,
            131071,
            131072,
            131073,
            1048575,
            1048576,
            1048577,
        ]

        for size in lens:
            if size < 24:
                hlen = 1
            elif size < 2**8:
                hlen = 2
            elif size < 2**16:
                hlen = 3
            elif size < 2**32:
                hlen = 5
            else:
                assert False

            source = b'x' * size
            encoded = b''.join(cborutil.streamencode(source))

            res = cborutil.decodeitem(encoded[0:1])

            if hlen > 1:
                self.assertEqual(res, (False, None, -(hlen - 1),
                                       cborutil.SPECIAL_NONE))
            else:
                self.assertEqual(res, (False, None, -(size + hlen - 1),
                                       cborutil.SPECIAL_NONE))

            # Decoding partial header reports remaining header size.
            for i in range(hlen - 1):
                self.assertEqual(cborutil.decodeitem(encoded[0:i + 1]),
                                 (False, None, -(hlen - i - 1),
                                  cborutil.SPECIAL_NONE))

            # Decoding complete header reports item size.
            self.assertEqual(cborutil.decodeitem(encoded[0:hlen]),
                             (False, None, -size, cborutil.SPECIAL_NONE))

            # Decoding single byte after header reports item size - 1
            self.assertEqual(cborutil.decodeitem(encoded[0:hlen + 1]),
                             (False, None, -(size - 1), cborutil.SPECIAL_NONE))

            # Decoding all but the last byte reports -1 needed.
            self.assertEqual(cborutil.decodeitem(encoded[0:hlen + size - 1]),
                             (False, None, -1, cborutil.SPECIAL_NONE))

            # Decoding last byte retrieves value.
            self.assertEqual(cborutil.decodeitem(encoded[0:hlen + size]),
                             (True, source, hlen + size, cborutil.SPECIAL_NONE))

    def testindefinitepartialdecode(self):
        encoded = b''.join(cborutil.streamencodebytestringfromiter(
            [b'foobar', b'biz']))

        # First item should be begin of bytestring special.
        self.assertEqual(cborutil.decodeitem(encoded[0:1]),
                         (True, None, 1,
                          cborutil.SPECIAL_START_INDEFINITE_BYTESTRING))

        # Second item should be the first chunk. But only available when
        # we give it 7 bytes (1 byte header + 6 byte chunk).
        self.assertEqual(cborutil.decodeitem(encoded[1:2]),
                         (False, None, -6, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[1:3]),
                         (False, None, -5, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[1:4]),
                         (False, None, -4, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[1:5]),
                         (False, None, -3, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[1:6]),
                         (False, None, -2, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[1:7]),
                         (False, None, -1, cborutil.SPECIAL_NONE))

        self.assertEqual(cborutil.decodeitem(encoded[1:8]),
                         (True, b'foobar', 7, cborutil.SPECIAL_NONE))

        # Third item should be second chunk. But only available when
        # we give it 4 bytes (1 byte header + 3 byte chunk).
        self.assertEqual(cborutil.decodeitem(encoded[8:9]),
                         (False, None, -3, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[8:10]),
                         (False, None, -2, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[8:11]),
                         (False, None, -1, cborutil.SPECIAL_NONE))

        self.assertEqual(cborutil.decodeitem(encoded[8:12]),
                         (True, b'biz', 4, cborutil.SPECIAL_NONE))

        # Fourth item should be end of indefinite stream marker.
        self.assertEqual(cborutil.decodeitem(encoded[12:13]),
                         (True, None, 1, cborutil.SPECIAL_INDEFINITE_BREAK))

        # Now test the behavior when going through the decoder.

        self.assertEqual(cborutil.sansiodecoder().decode(encoded[0:1]),
                         (False, 1, 0))
        self.assertEqual(cborutil.sansiodecoder().decode(encoded[0:2]),
                         (False, 1, 6))
        self.assertEqual(cborutil.sansiodecoder().decode(encoded[0:3]),
                         (False, 1, 5))
        self.assertEqual(cborutil.sansiodecoder().decode(encoded[0:4]),
                         (False, 1, 4))
        self.assertEqual(cborutil.sansiodecoder().decode(encoded[0:5]),
                         (False, 1, 3))
        self.assertEqual(cborutil.sansiodecoder().decode(encoded[0:6]),
                         (False, 1, 2))
        self.assertEqual(cborutil.sansiodecoder().decode(encoded[0:7]),
                         (False, 1, 1))
        self.assertEqual(cborutil.sansiodecoder().decode(encoded[0:8]),
                         (True, 8, 0))

        self.assertEqual(cborutil.sansiodecoder().decode(encoded[0:9]),
                         (True, 8, 3))
        self.assertEqual(cborutil.sansiodecoder().decode(encoded[0:10]),
                         (True, 8, 2))
        self.assertEqual(cborutil.sansiodecoder().decode(encoded[0:11]),
                         (True, 8, 1))
        self.assertEqual(cborutil.sansiodecoder().decode(encoded[0:12]),
                         (True, 12, 0))

        self.assertEqual(cborutil.sansiodecoder().decode(encoded[0:13]),
                         (True, 13, 0))

        decoder = cborutil.sansiodecoder()
        decoder.decode(encoded[0:8])
        values = decoder.getavailable()
        self.assertEqual(values, [b'foobar'])
        self.assertTrue(values[0].isfirst)
        self.assertFalse(values[0].islast)

        self.assertEqual(decoder.decode(encoded[8:12]),
                         (True, 4, 0))
        values = decoder.getavailable()
        self.assertEqual(values, [b'biz'])
        self.assertFalse(values[0].isfirst)
        self.assertFalse(values[0].islast)

        self.assertEqual(decoder.decode(encoded[12:]),
                         (True, 1, 0))
        values = decoder.getavailable()
        self.assertEqual(values, [b''])
        self.assertFalse(values[0].isfirst)
        self.assertTrue(values[0].islast)

class StringTests(TestCase):
    def testdecodeforbidden(self):
        encoded = b'\x63foo'
        with self.assertRaisesRegex(cborutil.CBORDecodeError,
                                    'string major type not supported'):
            cborutil.decodeall(encoded)

class IntTests(TestCase):
    def testsmall(self):
        self.assertEqual(list(cborutil.streamencode(0)), [b'\x00'])
        self.assertEqual(cborutil.decodeall(b'\x00'), [0])

        self.assertEqual(list(cborutil.streamencode(1)), [b'\x01'])
        self.assertEqual(cborutil.decodeall(b'\x01'), [1])

        self.assertEqual(list(cborutil.streamencode(2)), [b'\x02'])
        self.assertEqual(cborutil.decodeall(b'\x02'), [2])

        self.assertEqual(list(cborutil.streamencode(3)), [b'\x03'])
        self.assertEqual(cborutil.decodeall(b'\x03'), [3])

        self.assertEqual(list(cborutil.streamencode(4)), [b'\x04'])
        self.assertEqual(cborutil.decodeall(b'\x04'), [4])

        # Multiple value decode works.
        self.assertEqual(cborutil.decodeall(b'\x00\x01\x02\x03\x04'),
                         [0, 1, 2, 3, 4])

    def testnegativesmall(self):
        self.assertEqual(list(cborutil.streamencode(-1)), [b'\x20'])
        self.assertEqual(cborutil.decodeall(b'\x20'), [-1])

        self.assertEqual(list(cborutil.streamencode(-2)), [b'\x21'])
        self.assertEqual(cborutil.decodeall(b'\x21'), [-2])

        self.assertEqual(list(cborutil.streamencode(-3)), [b'\x22'])
        self.assertEqual(cborutil.decodeall(b'\x22'), [-3])

        self.assertEqual(list(cborutil.streamencode(-4)), [b'\x23'])
        self.assertEqual(cborutil.decodeall(b'\x23'), [-4])

        self.assertEqual(list(cborutil.streamencode(-5)), [b'\x24'])
        self.assertEqual(cborutil.decodeall(b'\x24'), [-5])

        # Multiple value decode works.
        self.assertEqual(cborutil.decodeall(b'\x20\x21\x22\x23\x24'),
                         [-1, -2, -3, -4, -5])

    def testrange(self):
        for i in range(-70000, 70000, 10):
            encoded = b''.join(cborutil.streamencode(i))

            self.assertEqual(encoded, cbor.dumps(i))
            self.assertEqual(cborutil.decodeall(encoded), [i])

    def testdecodepartialubyte(self):
        encoded = b''.join(cborutil.streamencode(250))

        self.assertEqual(cborutil.decodeitem(encoded[0:1]),
                         (False, None, -1, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:2]),
                         (True, 250, 2, cborutil.SPECIAL_NONE))

    def testdecodepartialbyte(self):
        encoded = b''.join(cborutil.streamencode(-42))
        self.assertEqual(cborutil.decodeitem(encoded[0:1]),
                         (False, None, -1, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:2]),
                         (True, -42, 2, cborutil.SPECIAL_NONE))

    def testdecodepartialushort(self):
        encoded = b''.join(cborutil.streamencode(2**15))

        self.assertEqual(cborutil.decodeitem(encoded[0:1]),
                         (False, None, -2, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:2]),
                         (False, None, -1, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:5]),
                         (True, 2**15, 3, cborutil.SPECIAL_NONE))

    def testdecodepartialshort(self):
        encoded = b''.join(cborutil.streamencode(-1024))

        self.assertEqual(cborutil.decodeitem(encoded[0:1]),
                         (False, None, -2, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:2]),
                         (False, None, -1, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:3]),
                         (True, -1024, 3, cborutil.SPECIAL_NONE))

    def testdecodepartialulong(self):
        encoded = b''.join(cborutil.streamencode(2**28))

        self.assertEqual(cborutil.decodeitem(encoded[0:1]),
                         (False, None, -4, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:2]),
                         (False, None, -3, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:3]),
                         (False, None, -2, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:4]),
                         (False, None, -1, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:5]),
                         (True, 2**28, 5, cborutil.SPECIAL_NONE))

    def testdecodepartiallong(self):
        encoded = b''.join(cborutil.streamencode(-1048580))

        self.assertEqual(cborutil.decodeitem(encoded[0:1]),
                         (False, None, -4, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:2]),
                         (False, None, -3, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:3]),
                         (False, None, -2, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:4]),
                         (False, None, -1, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:5]),
                         (True, -1048580, 5, cborutil.SPECIAL_NONE))

    def testdecodepartialulonglong(self):
        encoded = b''.join(cborutil.streamencode(2**32))

        self.assertEqual(cborutil.decodeitem(encoded[0:1]),
                         (False, None, -8, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:2]),
                         (False, None, -7, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:3]),
                         (False, None, -6, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:4]),
                         (False, None, -5, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:5]),
                         (False, None, -4, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:6]),
                         (False, None, -3, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:7]),
                         (False, None, -2, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:8]),
                         (False, None, -1, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:9]),
                         (True, 2**32, 9, cborutil.SPECIAL_NONE))

        with self.assertRaisesRegex(
            cborutil.CBORDecodeError, 'input data not fully consumed'):
            cborutil.decodeall(encoded[0:1])

        with self.assertRaisesRegex(
            cborutil.CBORDecodeError, 'input data not fully consumed'):
            cborutil.decodeall(encoded[0:2])

    def testdecodepartiallonglong(self):
        encoded = b''.join(cborutil.streamencode(-7000000000))

        self.assertEqual(cborutil.decodeitem(encoded[0:1]),
                         (False, None, -8, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:2]),
                         (False, None, -7, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:3]),
                         (False, None, -6, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:4]),
                         (False, None, -5, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:5]),
                         (False, None, -4, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:6]),
                         (False, None, -3, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:7]),
                         (False, None, -2, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:8]),
                         (False, None, -1, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:9]),
                         (True, -7000000000, 9, cborutil.SPECIAL_NONE))

class ArrayTests(TestCase):
    def testempty(self):
        self.assertEqual(list(cborutil.streamencode([])), [b'\x80'])
        self.assertEqual(loadit(cborutil.streamencode([])), [])

        self.assertEqual(cborutil.decodeall(b'\x80'), [[]])

    def testbasic(self):
        source = [b'foo', b'bar', 1, -10]

        chunks = [
            b'\x84', b'\x43', b'foo', b'\x43', b'bar', b'\x01', b'\x29']

        self.assertEqual(list(cborutil.streamencode(source)), chunks)

        self.assertEqual(cborutil.decodeall(b''.join(chunks)), [source])

    def testemptyfromiter(self):
        self.assertEqual(b''.join(cborutil.streamencodearrayfromiter([])),
                         b'\x9f\xff')

        with self.assertRaisesRegex(cborutil.CBORDecodeError,
                                    'indefinite length uint not allowed'):
            cborutil.decodeall(b'\x9f\xff')

    def testfromiter1(self):
        source = [b'foo']

        self.assertEqual(list(cborutil.streamencodearrayfromiter(source)), [
            b'\x9f',
            b'\x43', b'foo',
            b'\xff',
        ])

        dest = b''.join(cborutil.streamencodearrayfromiter(source))
        self.assertEqual(cbor.loads(dest), source)

        with self.assertRaisesRegex(cborutil.CBORDecodeError,
                                    'indefinite length uint not allowed'):
            cborutil.decodeall(dest)

    def testtuple(self):
        source = (b'foo', None, 42)
        encoded = b''.join(cborutil.streamencode(source))

        self.assertEqual(cbor.loads(encoded), list(source))

        self.assertEqual(cborutil.decodeall(encoded), [list(source)])

    def testpartialdecode(self):
        source = list(range(4))
        encoded = b''.join(cborutil.streamencode(source))
        self.assertEqual(cborutil.decodeitem(encoded[0:1]),
                         (True, 4, 1, cborutil.SPECIAL_START_ARRAY))
        self.assertEqual(cborutil.decodeitem(encoded[0:2]),
                         (True, 4, 1, cborutil.SPECIAL_START_ARRAY))

        source = list(range(23))
        encoded = b''.join(cborutil.streamencode(source))
        self.assertEqual(cborutil.decodeitem(encoded[0:1]),
                         (True, 23, 1, cborutil.SPECIAL_START_ARRAY))
        self.assertEqual(cborutil.decodeitem(encoded[0:2]),
                         (True, 23, 1, cborutil.SPECIAL_START_ARRAY))

        source = list(range(24))
        encoded = b''.join(cborutil.streamencode(source))
        self.assertEqual(cborutil.decodeitem(encoded[0:1]),
                         (False, None, -1, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:2]),
                         (True, 24, 2, cborutil.SPECIAL_START_ARRAY))
        self.assertEqual(cborutil.decodeitem(encoded[0:3]),
                         (True, 24, 2, cborutil.SPECIAL_START_ARRAY))

        source = list(range(256))
        encoded = b''.join(cborutil.streamencode(source))
        self.assertEqual(cborutil.decodeitem(encoded[0:1]),
                         (False, None, -2, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:2]),
                         (False, None, -1, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:3]),
                         (True, 256, 3, cborutil.SPECIAL_START_ARRAY))
        self.assertEqual(cborutil.decodeitem(encoded[0:4]),
                         (True, 256, 3, cborutil.SPECIAL_START_ARRAY))

    def testnested(self):
        source = [[], [], [[], [], []]]
        encoded = b''.join(cborutil.streamencode(source))
        self.assertEqual(cborutil.decodeall(encoded), [source])

        source = [True, None, [True, 0, 2], [None], [], [[[]], -87]]
        encoded = b''.join(cborutil.streamencode(source))
        self.assertEqual(cborutil.decodeall(encoded), [source])

        # A set within an array.
        source = [None, {b'foo', b'bar', None, False}, set()]
        encoded = b''.join(cborutil.streamencode(source))
        self.assertEqual(cborutil.decodeall(encoded), [source])

        # A map within an array.
        source = [None, {}, {b'foo': b'bar', True: False}, [{}]]
        encoded = b''.join(cborutil.streamencode(source))
        self.assertEqual(cborutil.decodeall(encoded), [source])

    def testindefinitebytestringvalues(self):
        # Single value array whose value is an empty indefinite bytestring.
        encoded = b'\x81\x5f\x40\xff'

        with self.assertRaisesRegex(cborutil.CBORDecodeError,
                                    'indefinite length bytestrings not '
                                    'allowed as array values'):
            cborutil.decodeall(encoded)

class SetTests(TestCase):
    def testempty(self):
        self.assertEqual(list(cborutil.streamencode(set())), [
            b'\xd9\x01\x02',
            b'\x80',
        ])

        self.assertEqual(cborutil.decodeall(b'\xd9\x01\x02\x80'), [set()])

    def testset(self):
        source = {b'foo', None, 42}
        encoded = b''.join(cborutil.streamencode(source))

        self.assertEqual(cbor.loads(encoded), source)

        self.assertEqual(cborutil.decodeall(encoded), [source])

    def testinvalidtag(self):
        # Must use array to encode sets.
        encoded = b'\xd9\x01\x02\xa0'

        with self.assertRaisesRegex(cborutil.CBORDecodeError,
                                    'expected array after finite set '
                                    'semantic tag'):
            cborutil.decodeall(encoded)

    def testpartialdecode(self):
        # Semantic tag item will be 3 bytes. Set header will be variable
        # depending on length.
        encoded = b''.join(cborutil.streamencode({i for i in range(23)}))
        self.assertEqual(cborutil.decodeitem(encoded[0:1]),
                         (False, None, -2, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:2]),
                         (False, None, -1, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:3]),
                         (False, None, -1, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:4]),
                         (True, 23, 4, cborutil.SPECIAL_START_SET))
        self.assertEqual(cborutil.decodeitem(encoded[0:5]),
                         (True, 23, 4, cborutil.SPECIAL_START_SET))

        encoded = b''.join(cborutil.streamencode({i for i in range(24)}))
        self.assertEqual(cborutil.decodeitem(encoded[0:1]),
                         (False, None, -2, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:2]),
                         (False, None, -1, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:3]),
                         (False, None, -1, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:4]),
                         (False, None, -1, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:5]),
                         (True, 24, 5, cborutil.SPECIAL_START_SET))
        self.assertEqual(cborutil.decodeitem(encoded[0:6]),
                         (True, 24, 5, cborutil.SPECIAL_START_SET))

        encoded = b''.join(cborutil.streamencode({i for i in range(256)}))
        self.assertEqual(cborutil.decodeitem(encoded[0:1]),
                         (False, None, -2, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:2]),
                         (False, None, -1, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:3]),
                         (False, None, -1, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:4]),
                         (False, None, -2, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:5]),
                         (False, None, -1, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:6]),
                         (True, 256, 6, cborutil.SPECIAL_START_SET))

    def testinvalidvalue(self):
        encoded = b''.join([
            b'\xd9\x01\x02', # semantic tag
            b'\x81', # array of size 1
            b'\x5f\x43foo\xff', # indefinite length bytestring "foo"
        ])

        with self.assertRaisesRegex(cborutil.CBORDecodeError,
                                    'indefinite length bytestrings not '
                                    'allowed as set values'):
            cborutil.decodeall(encoded)

        encoded = b''.join([
            b'\xd9\x01\x02',
            b'\x81',
            b'\x80', # empty array
        ])

        with self.assertRaisesRegex(cborutil.CBORDecodeError,
                                    'collections not allowed as set values'):
            cborutil.decodeall(encoded)

        encoded = b''.join([
            b'\xd9\x01\x02',
            b'\x81',
            b'\xa0', # empty map
        ])

        with self.assertRaisesRegex(cborutil.CBORDecodeError,
                                    'collections not allowed as set values'):
            cborutil.decodeall(encoded)

        encoded = b''.join([
            b'\xd9\x01\x02',
            b'\x81',
            b'\xd9\x01\x02\x81\x01', # set with integer 1
        ])

        with self.assertRaisesRegex(cborutil.CBORDecodeError,
                                    'collections not allowed as set values'):
            cborutil.decodeall(encoded)

class BoolTests(TestCase):
    def testbasic(self):
        self.assertEqual(list(cborutil.streamencode(True)),  [b'\xf5'])
        self.assertEqual(list(cborutil.streamencode(False)), [b'\xf4'])

        self.assertIs(loadit(cborutil.streamencode(True)), True)
        self.assertIs(loadit(cborutil.streamencode(False)), False)

        self.assertEqual(cborutil.decodeall(b'\xf4'), [False])
        self.assertEqual(cborutil.decodeall(b'\xf5'), [True])

        self.assertEqual(cborutil.decodeall(b'\xf4\xf5\xf5\xf4'),
                         [False, True, True, False])

class NoneTests(TestCase):
    def testbasic(self):
        self.assertEqual(list(cborutil.streamencode(None)), [b'\xf6'])

        self.assertIs(loadit(cborutil.streamencode(None)), None)

        self.assertEqual(cborutil.decodeall(b'\xf6'), [None])
        self.assertEqual(cborutil.decodeall(b'\xf6\xf6'), [None, None])

class MapTests(TestCase):
    def testempty(self):
        self.assertEqual(list(cborutil.streamencode({})), [b'\xa0'])
        self.assertEqual(loadit(cborutil.streamencode({})), {})

        self.assertEqual(cborutil.decodeall(b'\xa0'), [{}])

    def testemptyindefinite(self):
        self.assertEqual(list(cborutil.streamencodemapfromiter([])), [
            b'\xbf', b'\xff'])

        self.assertEqual(loadit(cborutil.streamencodemapfromiter([])), {})

        with self.assertRaisesRegex(cborutil.CBORDecodeError,
                                    'indefinite length uint not allowed'):
            cborutil.decodeall(b'\xbf\xff')

    def testone(self):
        source = {b'foo': b'bar'}
        self.assertEqual(list(cborutil.streamencode(source)), [
            b'\xa1', b'\x43', b'foo', b'\x43', b'bar'])

        self.assertEqual(loadit(cborutil.streamencode(source)), source)

        self.assertEqual(cborutil.decodeall(b'\xa1\x43foo\x43bar'), [source])

    def testmultiple(self):
        source = {
            b'foo': b'bar',
            b'baz': b'value1',
        }

        self.assertEqual(loadit(cborutil.streamencode(source)), source)

        self.assertEqual(
            loadit(cborutil.streamencodemapfromiter(source.items())),
            source)

        encoded = b''.join(cborutil.streamencode(source))
        self.assertEqual(cborutil.decodeall(encoded), [source])

    def testcomplex(self):
        source = {
            b'key': 1,
            2: -10,
        }

        self.assertEqual(loadit(cborutil.streamencode(source)),
                         source)

        self.assertEqual(
            loadit(cborutil.streamencodemapfromiter(source.items())),
            source)

        encoded = b''.join(cborutil.streamencode(source))
        self.assertEqual(cborutil.decodeall(encoded), [source])

    def testnested(self):
        source = {b'key1': None, b'key2': {b'sub1': b'sub2'}, b'sub2': {}}
        encoded = b''.join(cborutil.streamencode(source))

        self.assertEqual(cborutil.decodeall(encoded), [source])

        source = {
            b'key1': [],
            b'key2': [None, False],
            b'key3': {b'foo', b'bar'},
            b'key4': {},
        }
        encoded = b''.join(cborutil.streamencode(source))
        self.assertEqual(cborutil.decodeall(encoded), [source])

    def testillegalkey(self):
        encoded = b''.join([
            # map header + len 1
            b'\xa1',
            # indefinite length bytestring "foo" in key position
            b'\x5f\x03foo\xff'
        ])

        with self.assertRaisesRegex(cborutil.CBORDecodeError,
                                    'indefinite length bytestrings not '
                                    'allowed as map keys'):
            cborutil.decodeall(encoded)

        encoded = b''.join([
            b'\xa1',
            b'\x80', # empty array
            b'\x43foo',
        ])

        with self.assertRaisesRegex(cborutil.CBORDecodeError,
                                    'collections not supported as map keys'):
            cborutil.decodeall(encoded)

    def testillegalvalue(self):
        encoded = b''.join([
            b'\xa1', # map headers
            b'\x43foo', # key
            b'\x5f\x03bar\xff', # indefinite length value
        ])

        with self.assertRaisesRegex(cborutil.CBORDecodeError,
                                    'indefinite length bytestrings not '
                                    'allowed as map values'):
            cborutil.decodeall(encoded)

    def testpartialdecode(self):
        source = {b'key1': b'value1'}
        encoded = b''.join(cborutil.streamencode(source))

        self.assertEqual(cborutil.decodeitem(encoded[0:1]),
                         (True, 1, 1, cborutil.SPECIAL_START_MAP))
        self.assertEqual(cborutil.decodeitem(encoded[0:2]),
                         (True, 1, 1, cborutil.SPECIAL_START_MAP))

        source = {b'key%d' % i: None for i in range(23)}
        encoded = b''.join(cborutil.streamencode(source))
        self.assertEqual(cborutil.decodeitem(encoded[0:1]),
                         (True, 23, 1, cborutil.SPECIAL_START_MAP))

        source = {b'key%d' % i: None for i in range(24)}
        encoded = b''.join(cborutil.streamencode(source))
        self.assertEqual(cborutil.decodeitem(encoded[0:1]),
                         (False, None, -1, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:2]),
                         (True, 24, 2, cborutil.SPECIAL_START_MAP))
        self.assertEqual(cborutil.decodeitem(encoded[0:3]),
                         (True, 24, 2, cborutil.SPECIAL_START_MAP))

        source = {b'key%d' % i: None for i in range(256)}
        encoded = b''.join(cborutil.streamencode(source))
        self.assertEqual(cborutil.decodeitem(encoded[0:1]),
                         (False, None, -2, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:2]),
                         (False, None, -1, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:3]),
                         (True, 256, 3, cborutil.SPECIAL_START_MAP))
        self.assertEqual(cborutil.decodeitem(encoded[0:4]),
                         (True, 256, 3, cborutil.SPECIAL_START_MAP))

        source = {b'key%d' % i: None for i in range(65536)}
        encoded = b''.join(cborutil.streamencode(source))
        self.assertEqual(cborutil.decodeitem(encoded[0:1]),
                         (False, None, -4, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:2]),
                         (False, None, -3, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:3]),
                         (False, None, -2, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:4]),
                         (False, None, -1, cborutil.SPECIAL_NONE))
        self.assertEqual(cborutil.decodeitem(encoded[0:5]),
                         (True, 65536, 5, cborutil.SPECIAL_START_MAP))
        self.assertEqual(cborutil.decodeitem(encoded[0:6]),
                         (True, 65536, 5, cborutil.SPECIAL_START_MAP))

class SemanticTagTests(TestCase):
    def testdecodeforbidden(self):
        for i in range(500):
            if i == cborutil.SEMANTIC_TAG_FINITE_SET:
                continue

            tag = cborutil.encodelength(cborutil.MAJOR_TYPE_SEMANTIC,
                                        i)

            encoded = tag + cborutil.encodelength(cborutil.MAJOR_TYPE_UINT, 42)

            # Partial decode is incomplete.
            if i < 24:
                pass
            elif i < 256:
                self.assertEqual(cborutil.decodeitem(encoded[0:1]),
                                 (False, None, -1, cborutil.SPECIAL_NONE))
            elif i < 65536:
                self.assertEqual(cborutil.decodeitem(encoded[0:1]),
                                 (False, None, -2, cborutil.SPECIAL_NONE))
                self.assertEqual(cborutil.decodeitem(encoded[0:2]),
                                 (False, None, -1, cborutil.SPECIAL_NONE))

            with self.assertRaisesRegex(cborutil.CBORDecodeError,
                                        'semantic tag \d+ not allowed'):
                cborutil.decodeitem(encoded)

class SpecialTypesTests(TestCase):
    def testforbiddentypes(self):
        for i in range(256):
            if i == cborutil.SUBTYPE_FALSE:
                continue
            elif i == cborutil.SUBTYPE_TRUE:
                continue
            elif i == cborutil.SUBTYPE_NULL:
                continue

            encoded = cborutil.encodelength(cborutil.MAJOR_TYPE_SPECIAL, i)

            with self.assertRaisesRegex(cborutil.CBORDecodeError,
                                        'special type \d+ not allowed'):
                cborutil.decodeitem(encoded)

class SansIODecoderTests(TestCase):
    def testemptyinput(self):
        decoder = cborutil.sansiodecoder()
        self.assertEqual(decoder.decode(b''), (False, 0, 0))

class BufferingDecoderTests(TestCase):
    def testsimple(self):
        source = [
            b'foobar',
            b'x' * 128,
            {b'foo': b'bar'},
            True,
            False,
            None,
            [None for i in range(128)],
        ]

        encoded = b''.join(cborutil.streamencode(source))

        for step in range(1, 32):
            decoder = cborutil.bufferingdecoder()
            start = 0

            while start < len(encoded):
                decoder.decode(encoded[start:start + step])
                start += step

            self.assertEqual(decoder.getavailable(), [source])

    def testbytearray(self):
        source = b''.join(cborutil.streamencode(b'foobar'))

        decoder = cborutil.bufferingdecoder()
        decoder.decode(bytearray(source))

        self.assertEqual(decoder.getavailable(), [b'foobar'])

class DecodeallTests(TestCase):
    def testemptyinput(self):
        self.assertEqual(cborutil.decodeall(b''), [])

    def testpartialinput(self):
        encoded = b''.join([
            b'\x82', # array of 2 elements
            b'\x01', # integer 1
        ])

        with self.assertRaisesRegex(cborutil.CBORDecodeError,
                                    'input data not complete'):
            cborutil.decodeall(encoded)

if __name__ == '__main__':
    import silenttestrunner
    silenttestrunner.main(__name__)