# Copyright (C) 2007-2010 Canonical Ltd
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

"""Tests for indices."""

from .. import (
    errors,
    tests,
    transport,
    )
from ..bzr import (
    index as _mod_index,
    )


class ErrorTests(tests.TestCase):

    def test_bad_index_format_signature(self):
        error = _mod_index.BadIndexFormatSignature("foo", "bar")
        self.assertEqual("foo is not an index of type bar.",
                         str(error))

    def test_bad_index_data(self):
        error = _mod_index.BadIndexData("foo")
        self.assertEqual("Error in data for index foo.",
                         str(error))

    def test_bad_index_duplicate_key(self):
        error = _mod_index.BadIndexDuplicateKey("foo", "bar")
        self.assertEqual("The key 'foo' is already in index 'bar'.",
                         str(error))

    def test_bad_index_key(self):
        error = _mod_index.BadIndexKey("foo")
        self.assertEqual("The key 'foo' is not a valid key.",
                         str(error))

    def test_bad_index_options(self):
        error = _mod_index.BadIndexOptions("foo")
        self.assertEqual("Could not parse options for index foo.",
                         str(error))

    def test_bad_index_value(self):
        error = _mod_index.BadIndexValue("foo")
        self.assertEqual("The value 'foo' is not a valid value.",
                         str(error))


class TestGraphIndexBuilder(tests.TestCaseWithMemoryTransport):

    def test_build_index_empty(self):
        builder = _mod_index.GraphIndexBuilder()
        stream = builder.finish()
        contents = stream.read()
        self.assertEqual(
            b"Bazaar Graph Index 1\nnode_ref_lists=0\nkey_elements=1\nlen=0\n\n",
            contents)

    def test_build_index_empty_two_element_keys(self):
        builder = _mod_index.GraphIndexBuilder(key_elements=2)
        stream = builder.finish()
        contents = stream.read()
        self.assertEqual(
            b"Bazaar Graph Index 1\nnode_ref_lists=0\nkey_elements=2\nlen=0\n\n",
            contents)

    def test_build_index_one_reference_list_empty(self):
        builder = _mod_index.GraphIndexBuilder(reference_lists=1)
        stream = builder.finish()
        contents = stream.read()
        self.assertEqual(
            b"Bazaar Graph Index 1\nnode_ref_lists=1\nkey_elements=1\nlen=0\n\n",
            contents)

    def test_build_index_two_reference_list_empty(self):
        builder = _mod_index.GraphIndexBuilder(reference_lists=2)
        stream = builder.finish()
        contents = stream.read()
        self.assertEqual(
            b"Bazaar Graph Index 1\nnode_ref_lists=2\nkey_elements=1\nlen=0\n\n",
            contents)

    def test_build_index_one_node_no_refs(self):
        builder = _mod_index.GraphIndexBuilder()
        builder.add_node((b'akey', ), b'data')
        stream = builder.finish()
        contents = stream.read()
        self.assertEqual(
            b"Bazaar Graph Index 1\nnode_ref_lists=0\nkey_elements=1\nlen=1\n"
            b"akey\x00\x00\x00data\n\n", contents)

    def test_build_index_one_node_no_refs_accepts_empty_reflist(self):
        builder = _mod_index.GraphIndexBuilder()
        builder.add_node((b'akey', ), b'data', ())
        stream = builder.finish()
        contents = stream.read()
        self.assertEqual(
            b"Bazaar Graph Index 1\nnode_ref_lists=0\nkey_elements=1\nlen=1\n"
            b"akey\x00\x00\x00data\n\n", contents)

    def test_build_index_one_node_2_element_keys(self):
        # multipart keys are separated by \x00 - because they are fixed length,
        # not variable this does not cause any issues, and seems clearer to the
        # author.
        builder = _mod_index.GraphIndexBuilder(key_elements=2)
        builder.add_node((b'akey', b'secondpart'), b'data')
        stream = builder.finish()
        contents = stream.read()
        self.assertEqual(
            b"Bazaar Graph Index 1\nnode_ref_lists=0\nkey_elements=2\nlen=1\n"
            b"akey\x00secondpart\x00\x00\x00data\n\n", contents)

    def test_add_node_empty_value(self):
        builder = _mod_index.GraphIndexBuilder()
        builder.add_node((b'akey', ), b'')
        stream = builder.finish()
        contents = stream.read()
        self.assertEqual(
            b"Bazaar Graph Index 1\nnode_ref_lists=0\nkey_elements=1\nlen=1\n"
            b"akey\x00\x00\x00\n\n", contents)

    def test_build_index_nodes_sorted(self):
        # the highest sorted node comes first.
        builder = _mod_index.GraphIndexBuilder()
        # use three to have a good chance of glitching dictionary hash
        # lookups etc. Insert in randomish order that is not correct
        # and not the reverse of the correct order.
        builder.add_node((b'2002', ), b'data')
        builder.add_node((b'2000', ), b'data')
        builder.add_node((b'2001', ), b'data')
        stream = builder.finish()
        contents = stream.read()
        self.assertEqual(
            b"Bazaar Graph Index 1\nnode_ref_lists=0\nkey_elements=1\nlen=3\n"
            b"2000\x00\x00\x00data\n"
            b"2001\x00\x00\x00data\n"
            b"2002\x00\x00\x00data\n"
            b"\n", contents)

    def test_build_index_2_element_key_nodes_sorted(self):
        # multiple element keys are sorted first-key, second-key.
        builder = _mod_index.GraphIndexBuilder(key_elements=2)
        # use three values of each key element, to have a good chance of
        # glitching dictionary hash lookups etc. Insert in randomish order that
        # is not correct and not the reverse of the correct order.
        builder.add_node((b'2002', b'2002'), b'data')
        builder.add_node((b'2002', b'2000'), b'data')
        builder.add_node((b'2002', b'2001'), b'data')
        builder.add_node((b'2000', b'2002'), b'data')
        builder.add_node((b'2000', b'2000'), b'data')
        builder.add_node((b'2000', b'2001'), b'data')
        builder.add_node((b'2001', b'2002'), b'data')
        builder.add_node((b'2001', b'2000'), b'data')
        builder.add_node((b'2001', b'2001'), b'data')
        stream = builder.finish()
        contents = stream.read()
        self.assertEqual(
            b"Bazaar Graph Index 1\nnode_ref_lists=0\nkey_elements=2\nlen=9\n"
            b"2000\x002000\x00\x00\x00data\n"
            b"2000\x002001\x00\x00\x00data\n"
            b"2000\x002002\x00\x00\x00data\n"
            b"2001\x002000\x00\x00\x00data\n"
            b"2001\x002001\x00\x00\x00data\n"
            b"2001\x002002\x00\x00\x00data\n"
            b"2002\x002000\x00\x00\x00data\n"
            b"2002\x002001\x00\x00\x00data\n"
            b"2002\x002002\x00\x00\x00data\n"
            b"\n", contents)

    def test_build_index_reference_lists_are_included_one(self):
        builder = _mod_index.GraphIndexBuilder(reference_lists=1)
        builder.add_node((b'key', ), b'data', ([], ))
        stream = builder.finish()
        contents = stream.read()
        self.assertEqual(
            b"Bazaar Graph Index 1\nnode_ref_lists=1\nkey_elements=1\nlen=1\n"
            b"key\x00\x00\x00data\n"
            b"\n", contents)

    def test_build_index_reference_lists_with_2_element_keys(self):
        builder = _mod_index.GraphIndexBuilder(
            reference_lists=1, key_elements=2)
        builder.add_node((b'key', b'key2'), b'data', ([], ))
        stream = builder.finish()
        contents = stream.read()
        self.assertEqual(
            b"Bazaar Graph Index 1\nnode_ref_lists=1\nkey_elements=2\nlen=1\n"
            b"key\x00key2\x00\x00\x00data\n"
            b"\n", contents)

    def test_build_index_reference_lists_are_included_two(self):
        builder = _mod_index.GraphIndexBuilder(reference_lists=2)
        builder.add_node((b'key', ), b'data', ([], []))
        stream = builder.finish()
        contents = stream.read()
        self.assertEqual(
            b"Bazaar Graph Index 1\nnode_ref_lists=2\nkey_elements=1\nlen=1\n"
            b"key\x00\x00\t\x00data\n"
            b"\n", contents)

    def test_clear_cache(self):
        builder = _mod_index.GraphIndexBuilder(reference_lists=2)
        # This is a no-op, but the api should exist
        builder.clear_cache()

    def test_node_references_are_byte_offsets(self):
        builder = _mod_index.GraphIndexBuilder(reference_lists=1)
        builder.add_node((b'reference', ), b'data', ([], ))
        builder.add_node((b'key', ), b'data', ([(b'reference', )], ))
        stream = builder.finish()
        contents = stream.read()
        self.assertEqual(
            b"Bazaar Graph Index 1\nnode_ref_lists=1\nkey_elements=1\nlen=2\n"
            b"key\x00\x0072\x00data\n"
            b"reference\x00\x00\x00data\n"
            b"\n", contents)

    def test_node_references_are_cr_delimited(self):
        builder = _mod_index.GraphIndexBuilder(reference_lists=1)
        builder.add_node((b'reference', ), b'data', ([], ))
        builder.add_node((b'reference2', ), b'data', ([], ))
        builder.add_node((b'key', ), b'data',
                         ([(b'reference', ), (b'reference2', )], ))
        stream = builder.finish()
        contents = stream.read()
        self.assertEqual(
            b"Bazaar Graph Index 1\nnode_ref_lists=1\nkey_elements=1\nlen=3\n"
            b"key\x00\x00077\r094\x00data\n"
            b"reference\x00\x00\x00data\n"
            b"reference2\x00\x00\x00data\n"
            b"\n", contents)

    def test_multiple_reference_lists_are_tab_delimited(self):
        builder = _mod_index.GraphIndexBuilder(reference_lists=2)
        builder.add_node((b'keference', ), b'data', ([], []))
        builder.add_node((b'rey', ), b'data',
                         ([(b'keference', )], [(b'keference', )]))
        stream = builder.finish()
        contents = stream.read()
        self.assertEqual(
            b"Bazaar Graph Index 1\nnode_ref_lists=2\nkey_elements=1\nlen=2\n"
            b"keference\x00\x00\t\x00data\n"
            b"rey\x00\x0059\t59\x00data\n"
            b"\n", contents)

    def test_add_node_referencing_missing_key_makes_absent(self):
        builder = _mod_index.GraphIndexBuilder(reference_lists=1)
        builder.add_node((b'rey', ), b'data',
                         ([(b'beference', ), (b'aeference2', )], ))
        stream = builder.finish()
        contents = stream.read()
        self.assertEqual(
            b"Bazaar Graph Index 1\nnode_ref_lists=1\nkey_elements=1\nlen=1\n"
            b"aeference2\x00a\x00\x00\n"
            b"beference\x00a\x00\x00\n"
            b"rey\x00\x00074\r059\x00data\n"
            b"\n", contents)

    def test_node_references_three_digits(self):
        # test the node digit expands as needed.
        builder = _mod_index.GraphIndexBuilder(reference_lists=1)
        references = [((b"%d" % val), ) for val in range(8, -1, -1)]
        builder.add_node((b'2-key', ), b'', (references, ))
        stream = builder.finish()
        contents = stream.read()
        self.assertEqualDiff(
            b"Bazaar Graph Index 1\nnode_ref_lists=1\nkey_elements=1\nlen=1\n"
            b"0\x00a\x00\x00\n"
            b"1\x00a\x00\x00\n"
            b"2\x00a\x00\x00\n"
            b"2-key\x00\x00151\r145\r139\r133\r127\r121\r071\r065\r059\x00\n"
            b"3\x00a\x00\x00\n"
            b"4\x00a\x00\x00\n"
            b"5\x00a\x00\x00\n"
            b"6\x00a\x00\x00\n"
            b"7\x00a\x00\x00\n"
            b"8\x00a\x00\x00\n"
            b"\n", contents)

    def test_absent_has_no_reference_overhead(self):
        # the offsets after an absent record should be correct when there are
        # >1 reference lists.
        builder = _mod_index.GraphIndexBuilder(reference_lists=2)
        builder.add_node((b'parent', ), b'', ([(b'aail', ), (b'zther', )], []))
        stream = builder.finish()
        contents = stream.read()
        self.assertEqual(
            b"Bazaar Graph Index 1\nnode_ref_lists=2\nkey_elements=1\nlen=1\n"
            b"aail\x00a\x00\x00\n"
            b"parent\x00\x0059\r84\t\x00\n"
            b"zther\x00a\x00\x00\n"
            b"\n", contents)

    def test_add_node_bad_key(self):
        builder = _mod_index.GraphIndexBuilder()
        for bad_char in bytearray(b'\t\n\x0b\x0c\r\x00 '):
            self.assertRaises(_mod_index.BadIndexKey, builder.add_node,
                              (b'a%skey' % bytes([bad_char]), ), b'data')
        self.assertRaises(_mod_index.BadIndexKey, builder.add_node,
                          (), b'data')
        self.assertRaises(_mod_index.BadIndexKey, builder.add_node,
                          b'not-a-tuple', b'data')
        # not enough length
        self.assertRaises(_mod_index.BadIndexKey, builder.add_node,
                          (), b'data')
        # too long
        self.assertRaises(_mod_index.BadIndexKey, builder.add_node,
                          (b'primary', b'secondary'), b'data')
        # secondary key elements get checked too:
        builder = _mod_index.GraphIndexBuilder(key_elements=2)
        for bad_char in bytearray(b'\t\n\x0b\x0c\r\x00 '):
            self.assertRaises(_mod_index.BadIndexKey, builder.add_node,
                              (b'prefix', b'a%skey' % bytes([bad_char])), b'data')

    def test_add_node_bad_data(self):
        builder = _mod_index.GraphIndexBuilder()
        self.assertRaises(_mod_index.BadIndexValue, builder.add_node, (b'akey', ),
                          b'data\naa')
        self.assertRaises(_mod_index.BadIndexValue, builder.add_node, (b'akey', ),
                          b'data\x00aa')

    def test_add_node_bad_mismatched_ref_lists_length(self):
        builder = _mod_index.GraphIndexBuilder()
        self.assertRaises(_mod_index.BadIndexValue, builder.add_node, (b'akey', ),
                          b'data aa', ([], ))
        builder = _mod_index.GraphIndexBuilder(reference_lists=1)
        self.assertRaises(_mod_index.BadIndexValue, builder.add_node, (b'akey', ),
                          b'data aa')
        self.assertRaises(_mod_index.BadIndexValue, builder.add_node, (b'akey', ),
                          b'data aa', (), )
        self.assertRaises(_mod_index.BadIndexValue, builder.add_node, (b'akey', ),
                          b'data aa', ([], []))
        builder = _mod_index.GraphIndexBuilder(reference_lists=2)
        self.assertRaises(_mod_index.BadIndexValue, builder.add_node, (b'akey', ),
                          b'data aa')
        self.assertRaises(_mod_index.BadIndexValue, builder.add_node, (b'akey', ),
                          b'data aa', ([], ))
        self.assertRaises(_mod_index.BadIndexValue, builder.add_node, (b'akey', ),
                          b'data aa', ([], [], []))

    def test_add_node_bad_key_in_reference_lists(self):
        # first list, first key - trivial
        builder = _mod_index.GraphIndexBuilder(reference_lists=1)
        self.assertRaises(_mod_index.BadIndexKey, builder.add_node, (b'akey', ),
                          b'data aa', ([(b'a key', )], ))
        # references keys must be tuples too
        self.assertRaises(_mod_index.BadIndexKey, builder.add_node, (b'akey', ),
                          b'data aa', (['not-a-tuple'], ))
        # not enough length
        self.assertRaises(_mod_index.BadIndexKey, builder.add_node, (b'akey', ),
                          b'data aa', ([()], ))
        # too long
        self.assertRaises(_mod_index.BadIndexKey, builder.add_node, (b'akey', ),
                          b'data aa', ([(b'primary', b'secondary')], ))
        # need to check more than the first key in the list
        self.assertRaises(_mod_index.BadIndexKey, builder.add_node, (b'akey', ),
                          b'data aa', ([(b'agoodkey', ), (b'that is a bad key', )], ))
        # and if there is more than one list it should be getting checked
        # too
        builder = _mod_index.GraphIndexBuilder(reference_lists=2)
        self.assertRaises(_mod_index.BadIndexKey, builder.add_node, (b'akey', ),
                          b'data aa', ([], ['a bad key']))

    def test_add_duplicate_key(self):
        builder = _mod_index.GraphIndexBuilder()
        builder.add_node((b'key', ), b'data')
        self.assertRaises(_mod_index.BadIndexDuplicateKey,
                          builder.add_node, (b'key', ), b'data')

    def test_add_duplicate_key_2_elements(self):
        builder = _mod_index.GraphIndexBuilder(key_elements=2)
        builder.add_node((b'key', b'key'), b'data')
        self.assertRaises(_mod_index.BadIndexDuplicateKey, builder.add_node,
                          (b'key', b'key'), b'data')

    def test_add_key_after_referencing_key(self):
        builder = _mod_index.GraphIndexBuilder(reference_lists=1)
        builder.add_node((b'key', ), b'data', ([(b'reference', )], ))
        builder.add_node((b'reference', ), b'data', ([],))

    def test_add_key_after_referencing_key_2_elements(self):
        builder = _mod_index.GraphIndexBuilder(
            reference_lists=1, key_elements=2)
        builder.add_node((b'k', b'ey'), b'data',
                         ([(b'reference', b'tokey')], ))
        builder.add_node((b'reference', b'tokey'), b'data', ([],))

    def test_set_optimize(self):
        builder = _mod_index.GraphIndexBuilder(
            reference_lists=1, key_elements=2)
        builder.set_optimize(for_size=True)
        self.assertTrue(builder._optimize_for_size)
        builder.set_optimize(for_size=False)
        self.assertFalse(builder._optimize_for_size)


class TestGraphIndex(tests.TestCaseWithMemoryTransport):

    def make_key(self, number):
        return ((b'%d' % number) + b'X' * 100,)

    def make_value(self, number):
        return (b'%d' % number) + b'Y' * 100

    def make_nodes(self, count=64):
        # generate a big enough index that we only read some of it on a typical
        # bisection lookup.
        nodes = []
        for counter in range(count):
            nodes.append(
                (self.make_key(counter), self.make_value(counter), ()))
        return nodes

    def make_index(self, ref_lists=0, key_elements=1, nodes=[]):
        builder = _mod_index.GraphIndexBuilder(
            ref_lists, key_elements=key_elements)
        for key, value, references in nodes:
            builder.add_node(key, value, references)
        stream = builder.finish()
        trans = transport.get_transport_from_url('trace+' + self.get_url())
        size = trans.put_file('index', stream)
        return _mod_index.GraphIndex(trans, 'index', size)

    def make_index_with_offset(self, ref_lists=0, key_elements=1, nodes=[],
                               offset=0):
        builder = _mod_index.GraphIndexBuilder(
            ref_lists, key_elements=key_elements)
        for key, value, references in nodes:
            builder.add_node(key, value, references)
        content = builder.finish().read()
        size = len(content)
        trans = self.get_transport()
        trans.put_bytes('index', (b' ' * offset) + content)
        return _mod_index.GraphIndex(trans, 'index', size, offset=offset)

    def test_clear_cache(self):
        index = self.make_index()
        # For now, we just want to make sure the api is available. As this is
        # old code, we don't really worry if it *does* anything.
        index.clear_cache()

    def test_open_bad_index_no_error(self):
        trans = self.get_transport()
        trans.put_bytes('name', b"not an index\n")
        idx = _mod_index.GraphIndex(trans, 'name', 13)

    def test_with_offset(self):
        nodes = self.make_nodes(200)
        idx = self.make_index_with_offset(offset=1234567, nodes=nodes)
        self.assertEqual(200, idx.key_count())

    def test_buffer_all_with_offset(self):
        nodes = self.make_nodes(200)
        idx = self.make_index_with_offset(offset=1234567, nodes=nodes)
        idx._buffer_all()
        self.assertEqual(200, idx.key_count())

    def test_side_effect_buffering_with_offset(self):
        nodes = self.make_nodes(20)
        index = self.make_index_with_offset(offset=1234567, nodes=nodes)
        index._transport.recommended_page_size = lambda: 64 * 1024
        subset_nodes = [nodes[0][0], nodes[10][0], nodes[19][0]]
        entries = [n[1] for n in index.iter_entries(subset_nodes)]
        self.assertEqual(sorted(subset_nodes), sorted(entries))
        self.assertEqual(20, index.key_count())

    def test_open_sets_parsed_map_empty(self):
        index = self.make_index()
        self.assertEqual([], index._parsed_byte_map)
        self.assertEqual([], index._parsed_key_map)

    def test_key_count_buffers(self):
        index = self.make_index(nodes=self.make_nodes(2))
        # reset the transport log
        del index._transport._activity[:]
        self.assertEqual(2, index.key_count())
        # We should have requested reading the header bytes
        self.assertEqual([
            ('readv', 'index', [(0, 200)], True, index._size),
            ],
            index._transport._activity)
        # And that should have been enough to trigger reading the whole index
        # with buffering
        self.assertIsNot(None, index._nodes)

    def test_lookup_key_via_location_buffers(self):
        index = self.make_index()
        # reset the transport log
        del index._transport._activity[:]
        # do a _lookup_keys_via_location call for the middle of the file, which
        # is what bisection uses.
        result = index._lookup_keys_via_location(
            [(index._size // 2, (b'missing', ))])
        # this should have asked for a readv request, with adjust_for_latency,
        # and two regions: the header, and half-way into the file.
        self.assertEqual([
            ('readv', 'index', [(30, 30), (0, 200)], True, 60),
            ],
            index._transport._activity)
        # and the result should be that the key cannot be present, because this
        # is a trivial index.
        self.assertEqual([((index._size // 2, (b'missing', )), False)],
                         result)
        # And this should have caused the file to be fully buffered
        self.assertIsNot(None, index._nodes)
        self.assertEqual([], index._parsed_byte_map)

    def test_first_lookup_key_via_location(self):
        # We need enough data so that the _HEADER_READV doesn't consume the
        # whole file. We always read 800 bytes for every key, and the local
        # transport natural expansion is 4096 bytes. So we have to have >8192
        # bytes or we will trigger "buffer_all".
        # We also want the 'missing' key to fall within the range that *did*
        # read
        nodes = []
        index = self.make_index(nodes=self.make_nodes(64))
        # reset the transport log
        del index._transport._activity[:]
        # do a _lookup_keys_via_location call for the middle of the file, which
        # is what bisection uses.
        start_lookup = index._size // 2
        result = index._lookup_keys_via_location(
            [(start_lookup, (b'40missing', ))])
        # this should have asked for a readv request, with adjust_for_latency,
        # and two regions: the header, and half-way into the file.
        self.assertEqual([
            ('readv', 'index',
             [(start_lookup, 800), (0, 200)], True, index._size),
            ],
            index._transport._activity)
        # and the result should be that the key cannot be present, because this
        # is a trivial index.
        self.assertEqual([((start_lookup, (b'40missing', )), False)],
                         result)
        # And this should not have caused the file to be fully buffered
        self.assertIs(None, index._nodes)
        # And the regions of the file that have been parsed should be in the
        # parsed_byte_map and the parsed_key_map
        self.assertEqual([(0, 4008), (5046, 8996)], index._parsed_byte_map)
        self.assertEqual([((), self.make_key(26)),
                          (self.make_key(31), self.make_key(48))],
                         index._parsed_key_map)

    def test_parsing_non_adjacent_data_trims(self):
        index = self.make_index(nodes=self.make_nodes(64))
        result = index._lookup_keys_via_location(
            [(index._size // 2, (b'40', ))])
        # and the result should be that the key cannot be present, because key is
        # in the middle of the observed data from a 4K read - the smallest transport
        # will do today with this api.
        self.assertEqual([((index._size // 2, (b'40', )), False)],
                         result)
        # and we should have a parse map that includes the header and the
        # region that was parsed after trimming.
        self.assertEqual([(0, 4008), (5046, 8996)], index._parsed_byte_map)
        self.assertEqual([((), self.make_key(26)),
                          (self.make_key(31), self.make_key(48))],
                         index._parsed_key_map)

    def test_parsing_data_handles_parsed_contained_regions(self):
        # the following patten creates a parsed region that is wholly within a
        # single result from the readv layer:
        # .... single-read (readv-minimum-size) ...
        # which then trims the start and end so the parsed size is < readv
        # miniumum.
        # then a dual lookup (or a reference lookup for that matter) which
        # abuts or overlaps the parsed region on both sides will need to
        # discard the data in the middle, but parse the end as well.
        #
        # we test this by doing a single lookup to seed the data, then
        # a lookup for two keys that are present, and adjacent -
        # we except both to be found, and the parsed byte map to include the
        # locations of both keys.
        index = self.make_index(nodes=self.make_nodes(128))
        result = index._lookup_keys_via_location(
            [(index._size // 2, (b'40', ))])
        # and we should have a parse map that includes the header and the
        # region that was parsed after trimming.
        self.assertEqual([(0, 4045), (11759, 15707)], index._parsed_byte_map)
        self.assertEqual([((), self.make_key(116)),
                          (self.make_key(35), self.make_key(51))],
                         index._parsed_key_map)
        # now ask for two keys, right before and after the parsed region
        result = index._lookup_keys_via_location(
            [(11450, self.make_key(34)), (15707, self.make_key(52))])
        self.assertEqual([
            ((11450, self.make_key(34)),
             (index, self.make_key(34), self.make_value(34))),
            ((15707, self.make_key(52)),
             (index, self.make_key(52), self.make_value(52))),
            ],
            result)
        self.assertEqual([(0, 4045), (9889, 17993)], index._parsed_byte_map)

    def test_lookup_missing_key_answers_without_io_when_map_permits(self):
        # generate a big enough index that we only read some of it on a typical
        # bisection lookup.
        index = self.make_index(nodes=self.make_nodes(64))
        # lookup the keys in the middle of the file
        result = index._lookup_keys_via_location(
            [(index._size // 2, (b'40', ))])
        # check the parse map, this determines the test validity
        self.assertEqual([(0, 4008), (5046, 8996)], index._parsed_byte_map)
        self.assertEqual([((), self.make_key(26)),
                          (self.make_key(31), self.make_key(48))],
                         index._parsed_key_map)
        # reset the transport log
        del index._transport._activity[:]
        # now looking up a key in the portion of the file already parsed should
        # not create a new transport request, and should return False (cannot
        # be in the index) - even when the byte location we ask for is outside
        # the parsed region
        result = index._lookup_keys_via_location(
            [(4000, (b'40', ))])
        self.assertEqual([((4000, (b'40', )), False)],
                         result)
        self.assertEqual([], index._transport._activity)

    def test_lookup_present_key_answers_without_io_when_map_permits(self):
        # generate a big enough index that we only read some of it on a typical
        # bisection lookup.
        index = self.make_index(nodes=self.make_nodes(64))
        # lookup the keys in the middle of the file
        result = index._lookup_keys_via_location(
            [(index._size // 2, (b'40', ))])
        # check the parse map, this determines the test validity
        self.assertEqual([(0, 4008), (5046, 8996)], index._parsed_byte_map)
        self.assertEqual([((), self.make_key(26)),
                          (self.make_key(31), self.make_key(48))],
                         index._parsed_key_map)
        # reset the transport log
        del index._transport._activity[:]
        # now looking up a key in the portion of the file already parsed should
        # not create a new transport request, and should return False (cannot
        # be in the index) - even when the byte location we ask for is outside
        # the parsed region
        #
        result = index._lookup_keys_via_location([(4000, self.make_key(40))])
        self.assertEqual(
            [((4000, self.make_key(40)),
              (index, self.make_key(40), self.make_value(40)))],
            result)
        self.assertEqual([], index._transport._activity)

    def test_lookup_key_below_probed_area(self):
        # generate a big enough index that we only read some of it on a typical
        # bisection lookup.
        index = self.make_index(nodes=self.make_nodes(64))
        # ask for the key in the middle, but a key that is located in the
        # unparsed region before the middle.
        result = index._lookup_keys_via_location(
            [(index._size // 2, (b'30', ))])
        # check the parse map, this determines the test validity
        self.assertEqual([(0, 4008), (5046, 8996)], index._parsed_byte_map)
        self.assertEqual([((), self.make_key(26)),
                          (self.make_key(31), self.make_key(48))],
                         index._parsed_key_map)
        self.assertEqual([((index._size // 2, (b'30', )), -1)],
                         result)

    def test_lookup_key_above_probed_area(self):
        # generate a big enough index that we only read some of it on a typical
        # bisection lookup.
        index = self.make_index(nodes=self.make_nodes(64))
        # ask for the key in the middle, but a key that is located in the
        # unparsed region after the middle.
        result = index._lookup_keys_via_location(
            [(index._size // 2, (b'50', ))])
        # check the parse map, this determines the test validity
        self.assertEqual([(0, 4008), (5046, 8996)], index._parsed_byte_map)
        self.assertEqual([((), self.make_key(26)),
                          (self.make_key(31), self.make_key(48))],
                         index._parsed_key_map)
        self.assertEqual([((index._size // 2, (b'50', )), +1)],
                         result)

    def test_lookup_key_resolves_references(self):
        # generate a big enough index that we only read some of it on a typical
        # bisection lookup.
        nodes = []
        for counter in range(99):
            nodes.append((self.make_key(counter), self.make_value(counter),
                          ((self.make_key(counter + 20),),)))
        index = self.make_index(ref_lists=1, nodes=nodes)
        # lookup a key in the middle that does not exist, so that when we can
        # check that the referred-to-keys are not accessed automatically.
        index_size = index._size
        index_center = index_size // 2
        result = index._lookup_keys_via_location(
            [(index_center, (b'40', ))])
        # check the parse map - only the start and middle should have been
        # parsed.
        self.assertEqual([(0, 4027), (10198, 14028)], index._parsed_byte_map)
        self.assertEqual([((), self.make_key(17)),
                          (self.make_key(44), self.make_key(5))],
                         index._parsed_key_map)
        # and check the transport activity likewise.
        self.assertEqual(
            [('readv', 'index', [(index_center, 800), (0, 200)], True,
              index_size)],
            index._transport._activity)
        # reset the transport log for testing the reference lookup
        del index._transport._activity[:]
        # now looking up a key in the portion of the file already parsed should
        # only perform IO to resolve its key references.
        result = index._lookup_keys_via_location([(11000, self.make_key(45))])
        self.assertEqual(
            [((11000, self.make_key(45)),
              (index, self.make_key(45), self.make_value(45),
               ((self.make_key(65),),)))],
            result)
        self.assertEqual([('readv', 'index', [(15093, 800)], True, index_size)],
                         index._transport._activity)

    def test_lookup_key_can_buffer_all(self):
        nodes = []
        for counter in range(64):
            nodes.append((self.make_key(counter), self.make_value(counter),
                          ((self.make_key(counter + 20),),)))
        index = self.make_index(ref_lists=1, nodes=nodes)
        # lookup a key in the middle that does not exist, so that when we can
        # check that the referred-to-keys are not accessed automatically.
        index_size = index._size
        index_center = index_size // 2
        result = index._lookup_keys_via_location([(index_center, (b'40', ))])
        # check the parse map - only the start and middle should have been
        # parsed.
        self.assertEqual([(0, 3890), (6444, 10274)], index._parsed_byte_map)
        self.assertEqual([((), self.make_key(25)),
                          (self.make_key(37), self.make_key(52))],
                         index._parsed_key_map)
        # and check the transport activity likewise.
        self.assertEqual(
            [('readv', 'index', [(index_center, 800), (0, 200)], True,
              index_size)],
            index._transport._activity)
        # reset the transport log for testing the reference lookup
        del index._transport._activity[:]
        # now looking up a key in the portion of the file already parsed should
        # only perform IO to resolve its key references.
        result = index._lookup_keys_via_location([(7000, self.make_key(40))])
        self.assertEqual(
            [((7000, self.make_key(40)),
              (index, self.make_key(40), self.make_value(40),
               ((self.make_key(60),),)))],
            result)
        # Resolving the references would have required more data read, and we
        # are already above the 50% threshold, so it triggered a _buffer_all
        self.assertEqual([('get', 'index')], index._transport._activity)

    def test_iter_all_entries_empty(self):
        index = self.make_index()
        self.assertEqual([], list(index.iter_all_entries()))

    def test_iter_all_entries_simple(self):
        index = self.make_index(nodes=[((b'name', ), b'data', ())])
        self.assertEqual([(index, (b'name', ), b'data')],
                         list(index.iter_all_entries()))

    def test_iter_all_entries_simple_2_elements(self):
        index = self.make_index(key_elements=2,
                                nodes=[((b'name', b'surname'), b'data', ())])
        self.assertEqual([(index, (b'name', b'surname'), b'data')],
                         list(index.iter_all_entries()))

    def test_iter_all_entries_references_resolved(self):
        index = self.make_index(1, nodes=[
            ((b'name', ), b'data', ([(b'ref', )], )),
            ((b'ref', ), b'refdata', ([], ))])
        self.assertEqual({(index, (b'name', ), b'data', (((b'ref',),),)),
                          (index, (b'ref', ), b'refdata', ((), ))},
                         set(index.iter_all_entries()))

    def test_iter_entries_buffers_once(self):
        index = self.make_index(nodes=self.make_nodes(2))
        # reset the transport log
        del index._transport._activity[:]
        self.assertEqual({(index, self.make_key(1), self.make_value(1))},
                         set(index.iter_entries([self.make_key(1)])))
        # We should have requested reading the header bytes
        # But not needed any more than that because it would have triggered a
        # buffer all
        self.assertEqual([
            ('readv', 'index', [(0, 200)], True, index._size),
            ],
            index._transport._activity)
        # And that should have been enough to trigger reading the whole index
        # with buffering
        self.assertIsNot(None, index._nodes)

    def test_iter_entries_buffers_by_bytes_read(self):
        index = self.make_index(nodes=self.make_nodes(64))
        list(index.iter_entries([self.make_key(10)]))
        # The first time through isn't enough to trigger a buffer all
        self.assertIs(None, index._nodes)
        self.assertEqual(4096, index._bytes_read)
        # Grabbing a key in that same page won't trigger a buffer all, as we
        # still haven't read 50% of the file
        list(index.iter_entries([self.make_key(11)]))
        self.assertIs(None, index._nodes)
        self.assertEqual(4096, index._bytes_read)
        # We haven't read more data, so reading outside the range won't trigger
        # a buffer all right away
        list(index.iter_entries([self.make_key(40)]))
        self.assertIs(None, index._nodes)
        self.assertEqual(8192, index._bytes_read)
        # On the next pass, we will not trigger buffer all if the key is
        # available without reading more
        list(index.iter_entries([self.make_key(32)]))
        self.assertIs(None, index._nodes)
        # But if we *would* need to read more to resolve it, then we will
        # buffer all.
        list(index.iter_entries([self.make_key(60)]))
        self.assertIsNot(None, index._nodes)

    def test_iter_entries_references_resolved(self):
        index = self.make_index(1, nodes=[
            ((b'name', ), b'data', ([(b'ref', ), (b'ref', )], )),
            ((b'ref', ), b'refdata', ([], ))])
        self.assertEqual({(index, (b'name', ), b'data', (((b'ref',), (b'ref',)),)),
                          (index, (b'ref', ), b'refdata', ((), ))},
                         set(index.iter_entries([(b'name',), (b'ref',)])))

    def test_iter_entries_references_2_refs_resolved(self):
        index = self.make_index(2, nodes=[
            ((b'name', ), b'data', ([(b'ref', )], [(b'ref', )])),
            ((b'ref', ), b'refdata', ([], []))])
        self.assertEqual({(index, (b'name', ), b'data', (((b'ref',),), ((b'ref',),))),
                          (index, (b'ref', ), b'refdata', ((), ()))},
                         set(index.iter_entries([(b'name',), (b'ref',)])))

    def test_iteration_absent_skipped(self):
        index = self.make_index(1, nodes=[
            ((b'name', ), b'data', ([(b'ref', )], ))])
        self.assertEqual({(index, (b'name', ), b'data', (((b'ref',),),))},
                         set(index.iter_all_entries()))
        self.assertEqual({(index, (b'name', ), b'data', (((b'ref',),),))},
                         set(index.iter_entries([(b'name', )])))
        self.assertEqual([], list(index.iter_entries([(b'ref', )])))

    def test_iteration_absent_skipped_2_element_keys(self):
        index = self.make_index(1, key_elements=2, nodes=[
            ((b'name', b'fin'), b'data', ([(b'ref', b'erence')], ))])
        self.assertEqual([(index, (b'name', b'fin'), b'data', (((b'ref', b'erence'),),))],
                         list(index.iter_all_entries()))
        self.assertEqual([(index, (b'name', b'fin'), b'data', (((b'ref', b'erence'),),))],
                         list(index.iter_entries([(b'name', b'fin')])))
        self.assertEqual([], list(index.iter_entries([(b'ref', b'erence')])))

    def test_iter_all_keys(self):
        index = self.make_index(1, nodes=[
            ((b'name', ), b'data', ([(b'ref', )], )),
            ((b'ref', ), b'refdata', ([], ))])
        self.assertEqual({(index, (b'name', ), b'data', (((b'ref',),),)),
                          (index, (b'ref', ), b'refdata', ((), ))},
                         set(index.iter_entries([(b'name', ), (b'ref', )])))

    def test_iter_nothing_empty(self):
        index = self.make_index()
        self.assertEqual([], list(index.iter_entries([])))

    def test_iter_missing_entry_empty(self):
        index = self.make_index()
        self.assertEqual([], list(index.iter_entries([(b'a', )])))

    def test_iter_missing_entry_empty_no_size(self):
        idx = self.make_index()
        idx = _mod_index.GraphIndex(idx._transport, 'index', None)
        self.assertEqual([], list(idx.iter_entries([(b'a', )])))

    def test_iter_key_prefix_1_element_key_None(self):
        index = self.make_index()
        self.assertRaises(_mod_index.BadIndexKey, list,
                          index.iter_entries_prefix([(None, )]))

    def test_iter_key_prefix_wrong_length(self):
        index = self.make_index()
        self.assertRaises(_mod_index.BadIndexKey, list,
                          index.iter_entries_prefix([(b'foo', None)]))
        index = self.make_index(key_elements=2)
        self.assertRaises(_mod_index.BadIndexKey, list,
                          index.iter_entries_prefix([(b'foo', )]))
        self.assertRaises(_mod_index.BadIndexKey, list,
                          index.iter_entries_prefix([(b'foo', None, None)]))

    def test_iter_key_prefix_1_key_element_no_refs(self):
        index = self.make_index(nodes=[
            ((b'name', ), b'data', ()),
            ((b'ref', ), b'refdata', ())])
        self.assertEqual({(index, (b'name', ), b'data'),
                          (index, (b'ref', ), b'refdata')},
                         set(index.iter_entries_prefix([(b'name', ), (b'ref', )])))

    def test_iter_key_prefix_1_key_element_refs(self):
        index = self.make_index(1, nodes=[
            ((b'name', ), b'data', ([(b'ref', )], )),
            ((b'ref', ), b'refdata', ([], ))])
        self.assertEqual({(index, (b'name', ), b'data', (((b'ref',),),)),
                          (index, (b'ref', ), b'refdata', ((), ))},
                         set(index.iter_entries_prefix([(b'name', ), (b'ref', )])))

    def test_iter_key_prefix_2_key_element_no_refs(self):
        index = self.make_index(key_elements=2, nodes=[
            ((b'name', b'fin1'), b'data', ()),
            ((b'name', b'fin2'), b'beta', ()),
            ((b'ref', b'erence'), b'refdata', ())])
        self.assertEqual({(index, (b'name', b'fin1'), b'data'),
                          (index, (b'ref', b'erence'), b'refdata')},
                         set(index.iter_entries_prefix([(b'name', b'fin1'), (b'ref', b'erence')])))
        self.assertEqual({(index, (b'name', b'fin1'), b'data'),
                          (index, (b'name', b'fin2'), b'beta')},
                         set(index.iter_entries_prefix([(b'name', None)])))

    def test_iter_key_prefix_2_key_element_refs(self):
        index = self.make_index(1, key_elements=2, nodes=[
            ((b'name', b'fin1'), b'data', ([(b'ref', b'erence')], )),
            ((b'name', b'fin2'), b'beta', ([], )),
            ((b'ref', b'erence'), b'refdata', ([], ))])
        self.assertEqual({(index, (b'name', b'fin1'), b'data', (((b'ref', b'erence'),),)),
                          (index, (b'ref', b'erence'), b'refdata', ((), ))},
                         set(index.iter_entries_prefix([(b'name', b'fin1'), (b'ref', b'erence')])))
        self.assertEqual({(index, (b'name', b'fin1'), b'data', (((b'ref', b'erence'),),)),
                          (index, (b'name', b'fin2'), b'beta', ((), ))},
                         set(index.iter_entries_prefix([(b'name', None)])))

    def test_key_count_empty(self):
        index = self.make_index()
        self.assertEqual(0, index.key_count())

    def test_key_count_one(self):
        index = self.make_index(nodes=[((b'name', ), b'', ())])
        self.assertEqual(1, index.key_count())

    def test_key_count_two(self):
        index = self.make_index(nodes=[
            ((b'name', ), b'', ()), ((b'foo', ), b'', ())])
        self.assertEqual(2, index.key_count())

    def test_read_and_parse_tracks_real_read_value(self):
        index = self.make_index(nodes=self.make_nodes(10))
        del index._transport._activity[:]
        index._read_and_parse([(0, 200)])
        self.assertEqual([
            ('readv', 'index', [(0, 200)], True, index._size),
            ],
            index._transport._activity)
        # The readv expansion code will expand the initial request to 4096
        # bytes, which is more than enough to read the entire index, and we
        # will track the fact that we read that many bytes.
        self.assertEqual(index._size, index._bytes_read)

    def test_read_and_parse_triggers_buffer_all(self):
        index = self.make_index(key_elements=2, nodes=[
            ((b'name', b'fin1'), b'data', ()),
            ((b'name', b'fin2'), b'beta', ()),
            ((b'ref', b'erence'), b'refdata', ())])
        self.assertTrue(index._size > 0)
        self.assertIs(None, index._nodes)
        index._read_and_parse([(0, index._size)])
        self.assertIsNot(None, index._nodes)

    def test_validate_bad_index_errors(self):
        trans = self.get_transport()
        trans.put_bytes('name', b"not an index\n")
        idx = _mod_index.GraphIndex(trans, 'name', 13)
        self.assertRaises(_mod_index.BadIndexFormatSignature, idx.validate)

    def test_validate_bad_node_refs(self):
        idx = self.make_index(2)
        trans = self.get_transport()
        content = trans.get_bytes('index')
        # change the options line to end with a rather than a parseable number
        new_content = content[:-2] + b'a\n\n'
        trans.put_bytes('index', new_content)
        self.assertRaises(_mod_index.BadIndexOptions, idx.validate)

    def test_validate_missing_end_line_empty(self):
        index = self.make_index(2)
        trans = self.get_transport()
        content = trans.get_bytes('index')
        # truncate the last byte
        trans.put_bytes('index', content[:-1])
        self.assertRaises(_mod_index.BadIndexData, index.validate)

    def test_validate_missing_end_line_nonempty(self):
        index = self.make_index(2, nodes=[((b'key', ), b'', ([], []))])
        trans = self.get_transport()
        content = trans.get_bytes('index')
        # truncate the last byte
        trans.put_bytes('index', content[:-1])
        self.assertRaises(_mod_index.BadIndexData, index.validate)

    def test_validate_empty(self):
        index = self.make_index()
        index.validate()

    def test_validate_no_refs_content(self):
        index = self.make_index(nodes=[((b'key', ), b'value', ())])
        index.validate()

    # XXX: external_references tests are duplicated in test_btree_index.  We
    # probably should have per_graph_index tests...
    def test_external_references_no_refs(self):
        index = self.make_index(ref_lists=0, nodes=[])
        self.assertRaises(ValueError, index.external_references, 0)

    def test_external_references_no_results(self):
        index = self.make_index(ref_lists=1, nodes=[
            ((b'key',), b'value', ([],))])
        self.assertEqual(set(), index.external_references(0))

    def test_external_references_missing_ref(self):
        missing_key = (b'missing',)
        index = self.make_index(ref_lists=1, nodes=[
            ((b'key',), b'value', ([missing_key],))])
        self.assertEqual({missing_key}, index.external_references(0))

    def test_external_references_multiple_ref_lists(self):
        missing_key = (b'missing',)
        index = self.make_index(ref_lists=2, nodes=[
            ((b'key',), b'value', ([], [missing_key]))])
        self.assertEqual(set([]), index.external_references(0))
        self.assertEqual({missing_key}, index.external_references(1))

    def test_external_references_two_records(self):
        index = self.make_index(ref_lists=1, nodes=[
            ((b'key-1',), b'value', ([(b'key-2',)],)),
            ((b'key-2',), b'value', ([],)),
            ])
        self.assertEqual(set([]), index.external_references(0))

    def test__find_ancestors(self):
        key1 = (b'key-1',)
        key2 = (b'key-2',)
        index = self.make_index(ref_lists=1, key_elements=1, nodes=[
            (key1, b'value', ([key2],)),
            (key2, b'value', ([],)),
            ])
        parent_map = {}
        missing_keys = set()
        search_keys = index._find_ancestors(
            [key1], 0, parent_map, missing_keys)
        self.assertEqual({key1: (key2,)}, parent_map)
        self.assertEqual(set(), missing_keys)
        self.assertEqual({key2}, search_keys)
        search_keys = index._find_ancestors(search_keys, 0, parent_map,
                                            missing_keys)
        self.assertEqual({key1: (key2,), key2: ()}, parent_map)
        self.assertEqual(set(), missing_keys)
        self.assertEqual(set(), search_keys)

    def test__find_ancestors_w_missing(self):
        key1 = (b'key-1',)
        key2 = (b'key-2',)
        key3 = (b'key-3',)
        index = self.make_index(ref_lists=1, key_elements=1, nodes=[
            (key1, b'value', ([key2],)),
            (key2, b'value', ([],)),
            ])
        parent_map = {}
        missing_keys = set()
        search_keys = index._find_ancestors([key2, key3], 0, parent_map,
                                            missing_keys)
        self.assertEqual({key2: ()}, parent_map)
        self.assertEqual({key3}, missing_keys)
        self.assertEqual(set(), search_keys)

    def test__find_ancestors_dont_search_known(self):
        key1 = (b'key-1',)
        key2 = (b'key-2',)
        key3 = (b'key-3',)
        index = self.make_index(ref_lists=1, key_elements=1, nodes=[
            (key1, b'value', ([key2],)),
            (key2, b'value', ([key3],)),
            (key3, b'value', ([],)),
            ])
        # We already know about key2, so we won't try to search for key3
        parent_map = {key2: (key3,)}
        missing_keys = set()
        search_keys = index._find_ancestors([key1], 0, parent_map,
                                            missing_keys)
        self.assertEqual({key1: (key2,), key2: (key3,)}, parent_map)
        self.assertEqual(set(), missing_keys)
        self.assertEqual(set(), search_keys)

    def test_supports_unlimited_cache(self):
        builder = _mod_index.GraphIndexBuilder(0, key_elements=1)
        stream = builder.finish()
        trans = self.get_transport()
        size = trans.put_file('index', stream)
        # It doesn't matter what unlimited_cache does here, just that it can be
        # passed
        idx = _mod_index.GraphIndex(trans, 'index', size, unlimited_cache=True)


class TestCombinedGraphIndex(tests.TestCaseWithMemoryTransport):

    def make_index(self, name, ref_lists=0, key_elements=1, nodes=[]):
        builder = _mod_index.GraphIndexBuilder(
            ref_lists, key_elements=key_elements)
        for key, value, references in nodes:
            builder.add_node(key, value, references)
        stream = builder.finish()
        trans = self.get_transport()
        size = trans.put_file(name, stream)
        return _mod_index.GraphIndex(trans, name, size)

    def make_combined_index_with_missing(self, missing=['1', '2']):
        """Create a CombinedGraphIndex which will have missing indexes.

        This creates a CGI which thinks it has 2 indexes, however they have
        been deleted. If CGI._reload_func() is called, then it will repopulate
        with a new index.

        :param missing: The underlying indexes to delete
        :return: (CombinedGraphIndex, reload_counter)
        """
        idx1 = self.make_index('1', nodes=[((b'1',), b'', ())])
        idx2 = self.make_index('2', nodes=[((b'2',), b'', ())])
        idx3 = self.make_index('3', nodes=[
            ((b'1',), b'', ()),
            ((b'2',), b'', ())])

        # total_reloads, num_changed, num_unchanged
        reload_counter = [0, 0, 0]

        def reload():
            reload_counter[0] += 1
            new_indices = [idx3]
            if idx._indices == new_indices:
                reload_counter[2] += 1
                return False
            reload_counter[1] += 1
            idx._indices[:] = new_indices
            return True
        idx = _mod_index.CombinedGraphIndex([idx1, idx2], reload_func=reload)
        trans = self.get_transport()
        for fname in missing:
            trans.delete(fname)
        return idx, reload_counter

    def test_open_missing_index_no_error(self):
        trans = self.get_transport()
        idx1 = _mod_index.GraphIndex(trans, 'missing', 100)
        idx = _mod_index.CombinedGraphIndex([idx1])

    def test_add_index(self):
        idx = _mod_index.CombinedGraphIndex([])
        idx1 = self.make_index('name', 0, nodes=[((b'key', ), b'', ())])
        idx.insert_index(0, idx1)
        self.assertEqual([(idx1, (b'key', ), b'')],
                         list(idx.iter_all_entries()))

    def test_clear_cache(self):
        log = []

        class ClearCacheProxy(object):

            def __init__(self, index):
                self._index = index

            def __getattr__(self, name):
                return getattr(self._index)

            def clear_cache(self):
                log.append(self._index)
                return self._index.clear_cache()

        idx = _mod_index.CombinedGraphIndex([])
        idx1 = self.make_index('name', 0, nodes=[((b'key', ), b'', ())])
        idx.insert_index(0, ClearCacheProxy(idx1))
        idx2 = self.make_index('name', 0, nodes=[((b'key', ), b'', ())])
        idx.insert_index(1, ClearCacheProxy(idx2))
        # CombinedGraphIndex should call 'clear_cache()' on all children
        idx.clear_cache()
        self.assertEqual(sorted([idx1, idx2]), sorted(log))

    def test_iter_all_entries_empty(self):
        idx = _mod_index.CombinedGraphIndex([])
        self.assertEqual([], list(idx.iter_all_entries()))

    def test_iter_all_entries_children_empty(self):
        idx1 = self.make_index('name')
        idx = _mod_index.CombinedGraphIndex([idx1])
        self.assertEqual([], list(idx.iter_all_entries()))

    def test_iter_all_entries_simple(self):
        idx1 = self.make_index('name', nodes=[((b'name', ), b'data', ())])
        idx = _mod_index.CombinedGraphIndex([idx1])
        self.assertEqual([(idx1, (b'name', ), b'data')],
                         list(idx.iter_all_entries()))

    def test_iter_all_entries_two_indices(self):
        idx1 = self.make_index('name1', nodes=[((b'name', ), b'data', ())])
        idx2 = self.make_index('name2', nodes=[((b'2', ), b'', ())])
        idx = _mod_index.CombinedGraphIndex([idx1, idx2])
        self.assertEqual([(idx1, (b'name', ), b'data'),
                          (idx2, (b'2', ), b'')],
                         list(idx.iter_all_entries()))

    def test_iter_entries_two_indices_dup_key(self):
        idx1 = self.make_index('name1', nodes=[((b'name', ), b'data', ())])
        idx2 = self.make_index('name2', nodes=[((b'name', ), b'data', ())])
        idx = _mod_index.CombinedGraphIndex([idx1, idx2])
        self.assertEqual([(idx1, (b'name', ), b'data')],
                         list(idx.iter_entries([(b'name', )])))

    def test_iter_all_entries_two_indices_dup_key(self):
        idx1 = self.make_index('name1', nodes=[((b'name', ), b'data', ())])
        idx2 = self.make_index('name2', nodes=[((b'name', ), b'data', ())])
        idx = _mod_index.CombinedGraphIndex([idx1, idx2])
        self.assertEqual([(idx1, (b'name', ), b'data')],
                         list(idx.iter_all_entries()))

    def test_iter_key_prefix_2_key_element_refs(self):
        idx1 = self.make_index('1', 1, key_elements=2, nodes=[
            ((b'name', b'fin1'), b'data', ([(b'ref', b'erence')], ))])
        idx2 = self.make_index('2', 1, key_elements=2, nodes=[
            ((b'name', b'fin2'), b'beta', ([], )),
            ((b'ref', b'erence'), b'refdata', ([], ))])
        idx = _mod_index.CombinedGraphIndex([idx1, idx2])
        self.assertEqual({(idx1, (b'name', b'fin1'), b'data',
                           (((b'ref', b'erence'),),)),
                          (idx2, (b'ref', b'erence'), b'refdata', ((), ))},
                         set(idx.iter_entries_prefix([(b'name', b'fin1'),
                                                      (b'ref', b'erence')])))
        self.assertEqual({(idx1, (b'name', b'fin1'), b'data',
                           (((b'ref', b'erence'),),)),
                          (idx2, (b'name', b'fin2'), b'beta', ((), ))},
                         set(idx.iter_entries_prefix([(b'name', None)])))

    def test_iter_nothing_empty(self):
        idx = _mod_index.CombinedGraphIndex([])
        self.assertEqual([], list(idx.iter_entries([])))

    def test_iter_nothing_children_empty(self):
        idx1 = self.make_index('name')
        idx = _mod_index.CombinedGraphIndex([idx1])
        self.assertEqual([], list(idx.iter_entries([])))

    def test_iter_all_keys(self):
        idx1 = self.make_index('1', 1, nodes=[((b'name', ), b'data',
                                               ([(b'ref', )], ))])
        idx2 = self.make_index(
            '2', 1, nodes=[((b'ref', ), b'refdata', ((), ))])
        idx = _mod_index.CombinedGraphIndex([idx1, idx2])
        self.assertEqual({(idx1, (b'name', ), b'data', (((b'ref', ), ), )),
                          (idx2, (b'ref', ), b'refdata', ((), ))},
                         set(idx.iter_entries([(b'name', ), (b'ref', )])))

    def test_iter_all_keys_dup_entry(self):
        idx1 = self.make_index('1', 1, nodes=[((b'name', ), b'data',
                                               ([(b'ref', )], )),
                                              ((b'ref', ), b'refdata', ([], ))])
        idx2 = self.make_index(
            '2', 1, nodes=[((b'ref', ), b'refdata', ([], ))])
        idx = _mod_index.CombinedGraphIndex([idx1, idx2])
        self.assertEqual({(idx1, (b'name', ), b'data', (((b'ref',),),)),
                          (idx1, (b'ref', ), b'refdata', ((), ))},
                         set(idx.iter_entries([(b'name', ), (b'ref', )])))

    def test_iter_missing_entry_empty(self):
        idx = _mod_index.CombinedGraphIndex([])
        self.assertEqual([], list(idx.iter_entries([('a', )])))

    def test_iter_missing_entry_one_index(self):
        idx1 = self.make_index('1')
        idx = _mod_index.CombinedGraphIndex([idx1])
        self.assertEqual([], list(idx.iter_entries([(b'a', )])))

    def test_iter_missing_entry_two_index(self):
        idx1 = self.make_index('1')
        idx2 = self.make_index('2')
        idx = _mod_index.CombinedGraphIndex([idx1, idx2])
        self.assertEqual([], list(idx.iter_entries([('a', )])))

    def test_iter_entry_present_one_index_only(self):
        idx1 = self.make_index('1', nodes=[((b'key', ), b'', ())])
        idx2 = self.make_index('2', nodes=[])
        idx = _mod_index.CombinedGraphIndex([idx1, idx2])
        self.assertEqual([(idx1, (b'key', ), b'')],
                         list(idx.iter_entries([(b'key', )])))
        # and in the other direction
        idx = _mod_index.CombinedGraphIndex([idx2, idx1])
        self.assertEqual([(idx1, (b'key', ), b'')],
                         list(idx.iter_entries([(b'key', )])))

    def test_key_count_empty(self):
        idx1 = self.make_index('1', nodes=[])
        idx2 = self.make_index('2', nodes=[])
        idx = _mod_index.CombinedGraphIndex([idx1, idx2])
        self.assertEqual(0, idx.key_count())

    def test_key_count_sums_index_keys(self):
        idx1 = self.make_index('1', nodes=[
            ((b'1',), b'', ()),
            ((b'2',), b'', ())])
        idx2 = self.make_index('2', nodes=[((b'1',), b'', ())])
        idx = _mod_index.CombinedGraphIndex([idx1, idx2])
        self.assertEqual(3, idx.key_count())

    def test_validate_bad_child_index_errors(self):
        trans = self.get_transport()
        trans.put_bytes('name', b"not an index\n")
        idx1 = _mod_index.GraphIndex(trans, 'name', 13)
        idx = _mod_index.CombinedGraphIndex([idx1])
        self.assertRaises(_mod_index.BadIndexFormatSignature, idx.validate)

    def test_validate_empty(self):
        idx = _mod_index.CombinedGraphIndex([])
        idx.validate()

    def test_key_count_reloads(self):
        idx, reload_counter = self.make_combined_index_with_missing()
        self.assertEqual(2, idx.key_count())
        self.assertEqual([1, 1, 0], reload_counter)

    def test_key_count_no_reload(self):
        idx, reload_counter = self.make_combined_index_with_missing()
        idx._reload_func = None
        # Without a _reload_func we just raise the exception
        self.assertRaises(errors.NoSuchFile, idx.key_count)

    def test_key_count_reloads_and_fails(self):
        # We have deleted all underlying indexes, so we will try to reload, but
        # still fail. This is mostly to test we don't get stuck in an infinite
        # loop trying to reload
        idx, reload_counter = self.make_combined_index_with_missing(
            ['1', '2', '3'])
        self.assertRaises(errors.NoSuchFile, idx.key_count)
        self.assertEqual([2, 1, 1], reload_counter)

    def test_iter_entries_reloads(self):
        index, reload_counter = self.make_combined_index_with_missing()
        result = list(index.iter_entries([(b'1',), (b'2',), (b'3',)]))
        index3 = index._indices[0]
        self.assertEqual({(index3, (b'1',), b''), (index3, (b'2',), b'')},
                         set(result))
        self.assertEqual([1, 1, 0], reload_counter)

    def test_iter_entries_reloads_midway(self):
        # The first index still looks present, so we get interrupted mid-way
        # through
        index, reload_counter = self.make_combined_index_with_missing(['2'])
        index1, index2 = index._indices
        result = list(index.iter_entries([(b'1',), (b'2',), (b'3',)]))
        index3 = index._indices[0]
        # We had already yielded b'1', so we just go on to the next, we should
        # not yield b'1' twice.
        self.assertEqual([(index1, (b'1',), b''), (index3, (b'2',), b'')],
                         result)
        self.assertEqual([1, 1, 0], reload_counter)

    def test_iter_entries_no_reload(self):
        index, reload_counter = self.make_combined_index_with_missing()
        index._reload_func = None
        # Without a _reload_func we just raise the exception
        self.assertListRaises(errors.NoSuchFile, index.iter_entries, [('3',)])

    def test_iter_entries_reloads_and_fails(self):
        index, reload_counter = self.make_combined_index_with_missing(
            ['1', '2', '3'])
        self.assertListRaises(errors.NoSuchFile, index.iter_entries, [('3',)])
        self.assertEqual([2, 1, 1], reload_counter)

    def test_iter_all_entries_reloads(self):
        index, reload_counter = self.make_combined_index_with_missing()
        result = list(index.iter_all_entries())
        index3 = index._indices[0]
        self.assertEqual({(index3, (b'1',), b''), (index3, (b'2',), b'')},
                         set(result))
        self.assertEqual([1, 1, 0], reload_counter)

    def test_iter_all_entries_reloads_midway(self):
        index, reload_counter = self.make_combined_index_with_missing(['2'])
        index1, index2 = index._indices
        result = list(index.iter_all_entries())
        index3 = index._indices[0]
        # We had already yielded '1', so we just go on to the next, we should
        # not yield '1' twice.
        self.assertEqual([(index1, (b'1',), b''), (index3, (b'2',), b'')],
                         result)
        self.assertEqual([1, 1, 0], reload_counter)

    def test_iter_all_entries_no_reload(self):
        index, reload_counter = self.make_combined_index_with_missing()
        index._reload_func = None
        self.assertListRaises(errors.NoSuchFile, index.iter_all_entries)

    def test_iter_all_entries_reloads_and_fails(self):
        index, reload_counter = self.make_combined_index_with_missing(
            ['1', '2', '3'])
        self.assertListRaises(errors.NoSuchFile, index.iter_all_entries)

    def test_iter_entries_prefix_reloads(self):
        index, reload_counter = self.make_combined_index_with_missing()
        result = list(index.iter_entries_prefix([(b'1',)]))
        index3 = index._indices[0]
        self.assertEqual([(index3, (b'1',), b'')], result)
        self.assertEqual([1, 1, 0], reload_counter)

    def test_iter_entries_prefix_reloads_midway(self):
        index, reload_counter = self.make_combined_index_with_missing(['2'])
        index1, index2 = index._indices
        result = list(index.iter_entries_prefix([(b'1',)]))
        index3 = index._indices[0]
        # We had already yielded b'1', so we just go on to the next, we should
        # not yield b'1' twice.
        self.assertEqual([(index1, (b'1',), b'')], result)
        self.assertEqual([1, 1, 0], reload_counter)

    def test_iter_entries_prefix_no_reload(self):
        index, reload_counter = self.make_combined_index_with_missing()
        index._reload_func = None
        self.assertListRaises(errors.NoSuchFile, index.iter_entries_prefix,
                              [(b'1',)])

    def test_iter_entries_prefix_reloads_and_fails(self):
        index, reload_counter = self.make_combined_index_with_missing(
            ['1', '2', '3'])
        self.assertListRaises(errors.NoSuchFile, index.iter_entries_prefix,
                              [(b'1',)])

    def make_index_with_simple_nodes(self, name, num_nodes=1):
        """Make an index named after 'name', with keys named after 'name' too.

        Nodes will have a value of '' and no references.
        """
        nodes = [
            ((('index-%s-key-%s' % (name, n)).encode('ascii'),), b'', ())
            for n in range(1, num_nodes + 1)]
        return self.make_index('index-%s' % name, 0, nodes=nodes)

    def test_reorder_after_iter_entries(self):
        # Four indices: [key1] in idx1, [key2,key3] in idx2, [] in idx3,
        # [key4] in idx4.
        idx = _mod_index.CombinedGraphIndex([])
        idx.insert_index(0, self.make_index_with_simple_nodes('1'), b'1')
        idx.insert_index(1, self.make_index_with_simple_nodes('2'), b'2')
        idx.insert_index(2, self.make_index_with_simple_nodes('3'), b'3')
        idx.insert_index(3, self.make_index_with_simple_nodes('4'), b'4')
        idx1, idx2, idx3, idx4 = idx._indices
        # Query a key from idx4 and idx2.
        self.assertLength(2, list(idx.iter_entries(
            [(b'index-4-key-1',), (b'index-2-key-1',)])))
        # Now idx2 and idx4 should be moved to the front (and idx1 should
        # still be before idx3).
        self.assertEqual([idx2, idx4, idx1, idx3], idx._indices)
        self.assertEqual([b'2', b'4', b'1', b'3'], idx._index_names)

    def test_reorder_propagates_to_siblings(self):
        # Two CombinedGraphIndex objects, with the same number of indicies with
        # matching names.
        cgi1 = _mod_index.CombinedGraphIndex([])
        cgi2 = _mod_index.CombinedGraphIndex([])
        cgi1.insert_index(0, self.make_index_with_simple_nodes('1-1'), 'one')
        cgi1.insert_index(1, self.make_index_with_simple_nodes('1-2'), 'two')
        cgi2.insert_index(0, self.make_index_with_simple_nodes('2-1'), 'one')
        cgi2.insert_index(1, self.make_index_with_simple_nodes('2-2'), 'two')
        index2_1, index2_2 = cgi2._indices
        cgi1.set_sibling_indices([cgi2])
        # Trigger a reordering in cgi1.  cgi2 will be reordered as well.
        list(cgi1.iter_entries([(b'index-1-2-key-1',)]))
        self.assertEqual([index2_2, index2_1], cgi2._indices)
        self.assertEqual(['two', 'one'], cgi2._index_names)

    def test_validate_reloads(self):
        idx, reload_counter = self.make_combined_index_with_missing()
        idx.validate()
        self.assertEqual([1, 1, 0], reload_counter)

    def test_validate_reloads_midway(self):
        idx, reload_counter = self.make_combined_index_with_missing(['2'])
        idx.validate()

    def test_validate_no_reload(self):
        idx, reload_counter = self.make_combined_index_with_missing()
        idx._reload_func = None
        self.assertRaises(errors.NoSuchFile, idx.validate)

    def test_validate_reloads_and_fails(self):
        idx, reload_counter = self.make_combined_index_with_missing(
            ['1', '2', '3'])
        self.assertRaises(errors.NoSuchFile, idx.validate)

    def test_find_ancestors_across_indexes(self):
        key1 = (b'key-1',)
        key2 = (b'key-2',)
        key3 = (b'key-3',)
        key4 = (b'key-4',)
        index1 = self.make_index('12', ref_lists=1, nodes=[
            (key1, b'value', ([],)),
            (key2, b'value', ([key1],)),
            ])
        index2 = self.make_index('34', ref_lists=1, nodes=[
            (key3, b'value', ([key2],)),
            (key4, b'value', ([key3],)),
            ])
        c_index = _mod_index.CombinedGraphIndex([index1, index2])
        parent_map, missing_keys = c_index.find_ancestry([key1], 0)
        self.assertEqual({key1: ()}, parent_map)
        self.assertEqual(set(), missing_keys)
        # Now look for a key from index2 which requires us to find the key in
        # the second index, and then continue searching for parents in the
        # first index
        parent_map, missing_keys = c_index.find_ancestry([key3], 0)
        self.assertEqual({key1: (), key2: (key1,), key3: (key2,)}, parent_map)
        self.assertEqual(set(), missing_keys)

    def test_find_ancestors_missing_keys(self):
        key1 = (b'key-1',)
        key2 = (b'key-2',)
        key3 = (b'key-3',)
        key4 = (b'key-4',)
        index1 = self.make_index('12', ref_lists=1, nodes=[
            (key1, b'value', ([],)),
            (key2, b'value', ([key1],)),
            ])
        index2 = self.make_index('34', ref_lists=1, nodes=[
            (key3, b'value', ([key2],)),
            ])
        c_index = _mod_index.CombinedGraphIndex([index1, index2])
        # Searching for a key which is actually not present at all should
        # eventually converge
        parent_map, missing_keys = c_index.find_ancestry([key4], 0)
        self.assertEqual({}, parent_map)
        self.assertEqual({key4}, missing_keys)

    def test_find_ancestors_no_indexes(self):
        c_index = _mod_index.CombinedGraphIndex([])
        key1 = (b'key-1',)
        parent_map, missing_keys = c_index.find_ancestry([key1], 0)
        self.assertEqual({}, parent_map)
        self.assertEqual({key1}, missing_keys)

    def test_find_ancestors_ghost_parent(self):
        key1 = (b'key-1',)
        key2 = (b'key-2',)
        key3 = (b'key-3',)
        key4 = (b'key-4',)
        index1 = self.make_index('12', ref_lists=1, nodes=[
            (key1, b'value', ([],)),
            (key2, b'value', ([key1],)),
            ])
        index2 = self.make_index('34', ref_lists=1, nodes=[
            (key4, b'value', ([key2, key3],)),
            ])
        c_index = _mod_index.CombinedGraphIndex([index1, index2])
        # Searching for a key which is actually not present at all should
        # eventually converge
        parent_map, missing_keys = c_index.find_ancestry([key4], 0)
        self.assertEqual({key4: (key2, key3), key2: (key1,), key1: ()},
                         parent_map)
        self.assertEqual({key3}, missing_keys)

    def test__find_ancestors_empty_index(self):
        idx = self.make_index('test', ref_lists=1, key_elements=1, nodes=[])
        parent_map = {}
        missing_keys = set()
        search_keys = idx._find_ancestors([(b'one',), (b'two',)], 0, parent_map,
                                          missing_keys)
        self.assertEqual(set(), search_keys)
        self.assertEqual({}, parent_map)
        self.assertEqual({(b'one',), (b'two',)}, missing_keys)


class TestInMemoryGraphIndex(tests.TestCaseWithMemoryTransport):

    def make_index(self, ref_lists=0, key_elements=1, nodes=[]):
        result = _mod_index.InMemoryGraphIndex(
            ref_lists, key_elements=key_elements)
        result.add_nodes(nodes)
        return result

    def test_add_nodes_no_refs(self):
        index = self.make_index(0)
        index.add_nodes([((b'name', ), b'data')])
        index.add_nodes([((b'name2', ), b''), ((b'name3', ), b'')])
        self.assertEqual({
            (index, (b'name', ), b'data'),
            (index, (b'name2', ), b''),
            (index, (b'name3', ), b''),
            }, set(index.iter_all_entries()))

    def test_add_nodes(self):
        index = self.make_index(1)
        index.add_nodes([((b'name', ), b'data', ([],))])
        index.add_nodes([((b'name2', ), b'', ([],)),
                         ((b'name3', ), b'', ([(b'r', )],))])
        self.assertEqual({
            (index, (b'name', ), b'data', ((),)),
            (index, (b'name2', ), b'', ((),)),
            (index, (b'name3', ), b'', (((b'r', ), ), )),
            }, set(index.iter_all_entries()))

    def test_iter_all_entries_empty(self):
        index = self.make_index()
        self.assertEqual([], list(index.iter_all_entries()))

    def test_iter_all_entries_simple(self):
        index = self.make_index(nodes=[((b'name', ), b'data')])
        self.assertEqual([(index, (b'name', ), b'data')],
                         list(index.iter_all_entries()))

    def test_iter_all_entries_references(self):
        index = self.make_index(1, nodes=[
            ((b'name', ), b'data', ([(b'ref', )], )),
            ((b'ref', ), b'refdata', ([], ))])
        self.assertEqual({(index, (b'name', ), b'data', (((b'ref', ),),)),
                          (index, (b'ref', ), b'refdata', ((), ))},
                         set(index.iter_all_entries()))

    def test_iteration_absent_skipped(self):
        index = self.make_index(1, nodes=[
            ((b'name', ), b'data', ([(b'ref', )], ))])
        self.assertEqual({(index, (b'name', ), b'data', (((b'ref',),),))},
                         set(index.iter_all_entries()))
        self.assertEqual({(index, (b'name', ), b'data', (((b'ref',),),))},
                         set(index.iter_entries([(b'name', )])))
        self.assertEqual([], list(index.iter_entries([(b'ref', )])))

    def test_iter_all_keys(self):
        index = self.make_index(1, nodes=[
            ((b'name', ), b'data', ([(b'ref', )], )),
            ((b'ref', ), b'refdata', ([], ))])
        self.assertEqual({(index, (b'name', ), b'data', (((b'ref',),),)),
                          (index, (b'ref', ), b'refdata', ((), ))},
                         set(index.iter_entries([(b'name', ), (b'ref', )])))

    def test_iter_key_prefix_1_key_element_no_refs(self):
        index = self.make_index(nodes=[
            ((b'name', ), b'data'),
            ((b'ref', ), b'refdata')])
        self.assertEqual({(index, (b'name', ), b'data'),
                          (index, (b'ref', ), b'refdata')},
                         set(index.iter_entries_prefix([(b'name', ), (b'ref', )])))

    def test_iter_key_prefix_1_key_element_refs(self):
        index = self.make_index(1, nodes=[
            ((b'name', ), b'data', ([(b'ref', )], )),
            ((b'ref', ), b'refdata', ([], ))])
        self.assertEqual({(index, (b'name', ), b'data', (((b'ref',),),)),
                          (index, (b'ref', ), b'refdata', ((), ))},
                         set(index.iter_entries_prefix([(b'name', ), (b'ref', )])))

    def test_iter_key_prefix_2_key_element_no_refs(self):
        index = self.make_index(key_elements=2, nodes=[
            ((b'name', b'fin1'), b'data'),
            ((b'name', b'fin2'), b'beta'),
            ((b'ref', b'erence'), b'refdata')])
        self.assertEqual({(index, (b'name', b'fin1'), b'data'),
                          (index, (b'ref', b'erence'), b'refdata')},
                         set(index.iter_entries_prefix([(b'name', b'fin1'), (b'ref', b'erence')])))
        self.assertEqual({(index, (b'name', b'fin1'), b'data'),
                          (index, (b'name', b'fin2'), b'beta')},
                         set(index.iter_entries_prefix([(b'name', None)])))

    def test_iter_key_prefix_2_key_element_refs(self):
        index = self.make_index(1, key_elements=2, nodes=[
            ((b'name', b'fin1'), b'data', ([(b'ref', b'erence')], )),
            ((b'name', b'fin2'), b'beta', ([], )),
            ((b'ref', b'erence'), b'refdata', ([], ))])
        self.assertEqual({(index, (b'name', b'fin1'), b'data', (((b'ref', b'erence'),),)),
                          (index, (b'ref', b'erence'), b'refdata', ((), ))},
                         set(index.iter_entries_prefix([(b'name', b'fin1'), (b'ref', b'erence')])))
        self.assertEqual({(index, (b'name', b'fin1'), b'data', (((b'ref', b'erence'),),)),
                          (index, (b'name', b'fin2'), b'beta', ((), ))},
                         set(index.iter_entries_prefix([(b'name', None)])))

    def test_iter_nothing_empty(self):
        index = self.make_index()
        self.assertEqual([], list(index.iter_entries([])))

    def test_iter_missing_entry_empty(self):
        index = self.make_index()
        self.assertEqual([], list(index.iter_entries([b'a'])))

    def test_key_count_empty(self):
        index = self.make_index()
        self.assertEqual(0, index.key_count())

    def test_key_count_one(self):
        index = self.make_index(nodes=[((b'name', ), b'')])
        self.assertEqual(1, index.key_count())

    def test_key_count_two(self):
        index = self.make_index(nodes=[((b'name', ), b''), ((b'foo', ), b'')])
        self.assertEqual(2, index.key_count())

    def test_validate_empty(self):
        index = self.make_index()
        index.validate()

    def test_validate_no_refs_content(self):
        index = self.make_index(nodes=[((b'key', ), b'value')])
        index.validate()


class TestGraphIndexPrefixAdapter(tests.TestCaseWithMemoryTransport):

    def make_index(self, ref_lists=1, key_elements=2, nodes=[],
                   add_callback=False):
        result = _mod_index.InMemoryGraphIndex(
            ref_lists, key_elements=key_elements)
        result.add_nodes(nodes)
        if add_callback:
            add_nodes_callback = result.add_nodes
        else:
            add_nodes_callback = None
        adapter = _mod_index.GraphIndexPrefixAdapter(
            result, (b'prefix', ), key_elements - 1,
            add_nodes_callback=add_nodes_callback)
        return result, adapter

    def test_add_node(self):
        index, adapter = self.make_index(add_callback=True)
        adapter.add_node((b'key',), b'value', (((b'ref',),),))
        self.assertEqual({(index, (b'prefix', b'key'), b'value',
                           (((b'prefix', b'ref'),),))},
                         set(index.iter_all_entries()))

    def test_add_nodes(self):
        index, adapter = self.make_index(add_callback=True)
        adapter.add_nodes((
            ((b'key',), b'value', (((b'ref',),),)),
            ((b'key2',), b'value2', ((),)),
            ))
        self.assertEqual({
            (index, (b'prefix', b'key2'), b'value2', ((),)),
            (index, (b'prefix', b'key'), b'value', (((b'prefix', b'ref'),),))
            },
            set(index.iter_all_entries()))

    def test_construct(self):
        idx = _mod_index.InMemoryGraphIndex()
        adapter = _mod_index.GraphIndexPrefixAdapter(idx, (b'prefix', ), 1)

    def test_construct_with_callback(self):
        idx = _mod_index.InMemoryGraphIndex()
        adapter = _mod_index.GraphIndexPrefixAdapter(idx, (b'prefix', ), 1,
                                                     idx.add_nodes)

    def test_iter_all_entries_cross_prefix_map_errors(self):
        index, adapter = self.make_index(nodes=[
            ((b'prefix', b'key1'), b'data1', (((b'prefixaltered', b'key2'),),))])
        self.assertRaises(_mod_index.BadIndexData, list,
                          adapter.iter_all_entries())

    def test_iter_all_entries(self):
        index, adapter = self.make_index(nodes=[
            ((b'notprefix', b'key1'), b'data', ((), )),
            ((b'prefix', b'key1'), b'data1', ((), )),
            ((b'prefix', b'key2'), b'data2', (((b'prefix', b'key1'),),))])
        self.assertEqual({(index, (b'key1', ), b'data1', ((),)),
                          (index, (b'key2', ), b'data2', (((b'key1',),),))},
                         set(adapter.iter_all_entries()))

    def test_iter_entries(self):
        index, adapter = self.make_index(nodes=[
            ((b'notprefix', b'key1'), b'data', ((), )),
            ((b'prefix', b'key1'), b'data1', ((), )),
            ((b'prefix', b'key2'), b'data2', (((b'prefix', b'key1'),),))])
        # ask for many - get all
        self.assertEqual({(index, (b'key1', ), b'data1', ((),)),
                          (index, (b'key2', ), b'data2', (((b'key1', ),),))},
                         set(adapter.iter_entries([(b'key1', ), (b'key2', )])))
        # ask for one, get one
        self.assertEqual({(index, (b'key1', ), b'data1', ((),))},
                         set(adapter.iter_entries([(b'key1', )])))
        # ask for missing, get none
        self.assertEqual(set(),
                         set(adapter.iter_entries([(b'key3', )])))

    def test_iter_entries_prefix(self):
        index, adapter = self.make_index(key_elements=3, nodes=[
            ((b'notprefix', b'foo', b'key1'), b'data', ((), )),
            ((b'prefix', b'prefix2', b'key1'), b'data1', ((), )),
            ((b'prefix', b'prefix2', b'key2'), b'data2', (((b'prefix', b'prefix2', b'key1'),),))])
        # ask for a prefix, get the results for just that prefix, adjusted.
        self.assertEqual({(index, (b'prefix2', b'key1', ), b'data1', ((),)),
                          (index, (b'prefix2', b'key2', ), b'data2', (((b'prefix2', b'key1', ),),))},
                         set(adapter.iter_entries_prefix([(b'prefix2', None)])))

    def test_key_count_no_matching_keys(self):
        index, adapter = self.make_index(nodes=[
            ((b'notprefix', b'key1'), b'data', ((), ))])
        self.assertEqual(0, adapter.key_count())

    def test_key_count_some_keys(self):
        index, adapter = self.make_index(nodes=[
            ((b'notprefix', b'key1'), b'data', ((), )),
            ((b'prefix', b'key1'), b'data1', ((), )),
            ((b'prefix', b'key2'), b'data2', (((b'prefix', b'key1'),),))])
        self.assertEqual(2, adapter.key_count())

    def test_validate(self):
        index, adapter = self.make_index()
        calls = []

        def validate():
            calls.append('called')
        index.validate = validate
        adapter.validate()
        self.assertEqual(['called'], calls)
