# pylint: disable=no-member
"""
Unit tests for the Mixed Modulestore, with DDT for the various stores (Split, Draft, XML)
"""
import datetime
import ddt
import itertools
import pymongo

from collections import namedtuple
from importlib import import_module
from pytz import UTC
from uuid import uuid4

# Mixed modulestore depends on django, so we'll manually configure some django settings
# before importing the module
# TODO remove this import and the configuration -- xmodule should not depend on django!
from django.conf import settings
from xmodule.modulestore.edit_info import EditInfoMixin
from xmodule.modulestore.inheritance import InheritanceMixin
from xmodule.modulestore.tests.test_cross_modulestore_import_export import MongoContentstoreBuilder
from xmodule.contentstore.content import StaticContent
import mimetypes
from opaque_keys.edx.keys import CourseKey
from xmodule.modulestore.xml_importer import import_from_xml
from nose import SkipTest

if not settings.configured:
    settings.configure()

from opaque_keys.edx.locations import SlashSeparatedCourseKey
from opaque_keys.edx.locator import BlockUsageLocator, CourseLocator
from xmodule.exceptions import InvalidVersionError
from xmodule.modulestore import ModuleStoreEnum
from xmodule.modulestore.draft_and_published import UnsupportedRevisionError, ModuleStoreDraftAndPublished
from xmodule.modulestore.exceptions import ItemNotFoundError, DuplicateCourseError, ReferentialIntegrityError, NoPathToItem
from xmodule.modulestore.mixed import MixedModuleStore
from xmodule.modulestore.search import path_to_location
from xmodule.modulestore.tests.factories import check_mongo_calls, check_exact_number_of_calls, \
    mongo_uses_error_check
from xmodule.modulestore.tests.mongo_connection import MONGO_PORT_NUM, MONGO_HOST
from xmodule.tests import DATA_DIR, CourseComparisonTest


@ddt.ddt
class TestMixedModuleStore(CourseComparisonTest):
    """
    Quasi-superclass which tests Location based apps against both split and mongo dbs (Locator and
    Location-based dbs)
    """
    HOST = MONGO_HOST
    PORT = MONGO_PORT_NUM
    DB = 'test_mongo_%s' % uuid4().hex[:5]
    COLLECTION = 'modulestore'
    ASSET_COLLECTION = 'assetstore'
    FS_ROOT = DATA_DIR
    DEFAULT_CLASS = 'xmodule.raw_module.RawDescriptor'
    RENDER_TEMPLATE = lambda t_n, d, ctx = None, nsp = 'main': ''

    MONGO_COURSEID = 'MITx/999/2013_Spring'
    XML_COURSEID1 = 'edX/toy/2012_Fall'
    XML_COURSEID2 = 'edX/simple/2012_Fall'
    BAD_COURSE_ID = 'edX/simple'

    modulestore_options = {
        'default_class': DEFAULT_CLASS,
        'fs_root': DATA_DIR,
        'render_template': RENDER_TEMPLATE,
        'xblock_mixins': (EditInfoMixin, InheritanceMixin),
    }
    DOC_STORE_CONFIG = {
        'host': HOST,
        'port': PORT,
        'db': DB,
        'collection': COLLECTION,
        'asset_collection': ASSET_COLLECTION,
    }
    MAPPINGS = {
        XML_COURSEID1: 'xml',
        XML_COURSEID2: 'xml',
        BAD_COURSE_ID: 'xml',
    }
    OPTIONS = {
        'stores': [
            {
                'NAME': 'draft',
                'ENGINE': 'xmodule.modulestore.mongo.draft.DraftModuleStore',
                'DOC_STORE_CONFIG': DOC_STORE_CONFIG,
                'OPTIONS': modulestore_options
            },
            {
                'NAME': 'split',
                'ENGINE': 'xmodule.modulestore.split_mongo.split_draft.DraftVersioningModuleStore',
                'DOC_STORE_CONFIG': DOC_STORE_CONFIG,
                'OPTIONS': modulestore_options
            },
            {
                'NAME': 'xml',
                'ENGINE': 'xmodule.modulestore.xml.XMLModuleStore',
                'OPTIONS': {
                    'data_dir': DATA_DIR,
                    'default_class': 'xmodule.hidden_module.HiddenDescriptor',
                    'xblock_mixins': (EditInfoMixin, InheritanceMixin),
                }
            },
        ]
    }

    def _compare_ignore_version(self, loc1, loc2, msg=None):
        """
        AssertEqual replacement for CourseLocator
        """
        if loc1.for_branch(None) != loc2.for_branch(None):
            self.fail(self._formatMessage(msg, u"{} != {}".format(unicode(loc1), unicode(loc2))))

    def setUp(self):
        """
        Set up the database for testing
        """
        super(TestMixedModuleStore, self).setUp()

        self.exclude_field(None, 'wiki_slug')
        self.exclude_field(None, 'xml_attributes')
        self.exclude_field(None, 'parent')
        self.ignore_asset_key('_id')
        self.ignore_asset_key('uploadDate')
        self.ignore_asset_key('content_son')
        self.ignore_asset_key('thumbnail_location')

        self.options = getattr(self, 'options', self.OPTIONS)
        self.connection = pymongo.MongoClient(
            host=self.HOST,
            port=self.PORT,
            tz_aware=True,
        )
        self.connection.drop_database(self.DB)
        self.addCleanup(self.connection.drop_database, self.DB)
        self.addCleanup(self.connection.close)

        self.addTypeEqualityFunc(BlockUsageLocator, '_compare_ignore_version')
        self.addTypeEqualityFunc(CourseLocator, '_compare_ignore_version')
        # define attrs which get set in initdb to quell pylint
        self.writable_chapter_location = self.store = self.fake_location = self.xml_chapter_location = None
        self.course_locations = {}

        self.user_id = ModuleStoreEnum.UserID.test

    # pylint: disable=invalid-name
    def _create_course(self, course_key):
        """
        Create a course w/ one item in the persistence store using the given course & item location.
        """
        # create course
        with self.store.bulk_operations(course_key):
            self.course = self.store.create_course(course_key.org, course_key.course, course_key.run, self.user_id)
            if isinstance(self.course.id, CourseLocator):
                self.course_locations[self.MONGO_COURSEID] = self.course.location
            else:
                self.assertEqual(self.course.id, course_key)

            # create chapter
            chapter = self.store.create_child(self.user_id, self.course.location, 'chapter', block_id='Overview')
            self.writable_chapter_location = chapter.location

    def _create_block_hierarchy(self):
        """
        Creates a hierarchy of blocks for testing
        Each block's (version_agnostic) location is assigned as a field of the class and can be easily accessed
        """
        BlockInfo = namedtuple('BlockInfo', 'field_name, category, display_name, sub_tree')

        trees = [
            BlockInfo(
                'chapter_x', 'chapter', 'Chapter_x', [
                    BlockInfo(
                        'sequential_x1', 'sequential', 'Sequential_x1', [
                            BlockInfo(
                                'vertical_x1a', 'vertical', 'Vertical_x1a', [
                                    BlockInfo('problem_x1a_1', 'problem', 'Problem_x1a_1', []),
                                    BlockInfo('problem_x1a_2', 'problem', 'Problem_x1a_2', []),
                                    BlockInfo('problem_x1a_3', 'problem', 'Problem_x1a_3', []),
                                    BlockInfo('html_x1a_1', 'html', 'HTML_x1a_1', []),
                                ]
                            ),
                            BlockInfo(
                                'vertical_x1b', 'vertical', 'Vertical_x1b', []
                            )
                        ]
                    ),
                    BlockInfo(
                        'sequential_x2', 'sequential', 'Sequential_x2', []
                    )
                ]
            ),
            BlockInfo(
                'chapter_y', 'chapter', 'Chapter_y', [
                    BlockInfo(
                        'sequential_y1', 'sequential', 'Sequential_y1', [
                            BlockInfo(
                                'vertical_y1a', 'vertical', 'Vertical_y1a', [
                                    BlockInfo('problem_y1a_1', 'problem', 'Problem_y1a_1', []),
                                    BlockInfo('problem_y1a_2', 'problem', 'Problem_y1a_2', []),
                                    BlockInfo('problem_y1a_3', 'problem', 'Problem_y1a_3', []),
                                ]
                            )
                        ]
                    )
                ]
            )
        ]

        def create_sub_tree(parent, block_info):
            """
            recursive function that creates the given block and its descendants
            """
            block = self.store.create_child(
                self.user_id, parent.location,
                block_info.category, block_id=block_info.display_name,
                fields={'display_name': block_info.display_name},
            )
            for tree in block_info.sub_tree:
                create_sub_tree(block, tree)
            setattr(self, block_info.field_name, block.location)

        with self.store.bulk_operations(self.course.id):
            for tree in trees:
                create_sub_tree(self.course, tree)

    def _course_key_from_string(self, string):
        """
        Get the course key for the given course string
        """
        return self.course_locations[string].course_key

    # pylint: disable=dangerous-default-value
    def _initialize_mixed(self, mappings=MAPPINGS, contentstore=None):
        """
        initializes the mixed modulestore.
        """
        self.store = MixedModuleStore(
            contentstore, create_modulestore_instance=create_modulestore_instance,
            mappings=mappings,
            **self.options
        )
        self.addCleanup(self.store.close_all_connections)

    def initdb(self, default):
        """
        Initialize the database and create one test course in it
        """
        # set the default modulestore
        store_configs = self.options['stores']
        for index in range(len(store_configs)):
            if store_configs[index]['NAME'] == default:
                if index > 0:
                    store_configs[index], store_configs[0] = store_configs[0], store_configs[index]
                break
        self._initialize_mixed()

        # convert to CourseKeys
        self.course_locations = {
            course_id: CourseLocator.from_string(course_id)
            for course_id in [self.MONGO_COURSEID, self.XML_COURSEID1, self.XML_COURSEID2]
        }
        # and then to the root UsageKey
        self.course_locations = {
            course_id: course_key.make_usage_key('course', course_key.run)
            for course_id, course_key in self.course_locations.iteritems()  # pylint: disable=maybe-no-member
        }

        mongo_course_key = self.course_locations[self.MONGO_COURSEID].course_key
        self.fake_location = self.store.make_course_key(mongo_course_key.org, mongo_course_key.course, mongo_course_key.run).make_usage_key('vertical', 'fake')

        self.xml_chapter_location = self.course_locations[self.XML_COURSEID1].replace(
            category='chapter', name='Overview'
        )
        self._create_course(self.course_locations[self.MONGO_COURSEID].course_key)

    @ddt.data('draft', 'split')
    def test_get_modulestore_type(self, default_ms):
        """
        Make sure we get back the store type we expect for given mappings
        """
        self.initdb(default_ms)
        self.assertEqual(self.store.get_modulestore_type(
            self._course_key_from_string(self.XML_COURSEID1)), ModuleStoreEnum.Type.xml
        )
        self.assertEqual(self.store.get_modulestore_type(
            self._course_key_from_string(self.XML_COURSEID2)), ModuleStoreEnum.Type.xml
        )
        mongo_ms_type = ModuleStoreEnum.Type.mongo if default_ms == 'draft' else ModuleStoreEnum.Type.split
        self.assertEqual(self.store.get_modulestore_type(
            self._course_key_from_string(self.MONGO_COURSEID)), mongo_ms_type
        )
        # try an unknown mapping, it should be the 'default' store
        self.assertEqual(self.store.get_modulestore_type(
            SlashSeparatedCourseKey('foo', 'bar', '2012_Fall')), mongo_ms_type
        )

    @ddt.data('draft', 'split')
    def test_get_modulestore_cache(self, default_ms):
        """
        Make sure we cache discovered course mappings
        """
        self.initdb(default_ms)
        # unset mappings
        self.store.mappings = {}
        course_key = self.course_locations[self.MONGO_COURSEID].course_key
        with check_exact_number_of_calls(self.store.default_modulestore, 'has_course', 1):
            self.assertEqual(self.store.default_modulestore, self.store._get_modulestore_for_courseid(course_key))
            self.assertIn(course_key, self.store.mappings)
            self.assertEqual(self.store.default_modulestore, self.store._get_modulestore_for_courseid(course_key))

    @ddt.data(*itertools.product(
        (ModuleStoreEnum.Type.mongo, ModuleStoreEnum.Type.split),
        (True, False)
    ))
    @ddt.unpack
    def test_duplicate_course_error(self, default_ms, reset_mixed_mappings):
        """
        Make sure we get back the store type we expect for given mappings
        """
        self._initialize_mixed(mappings={})
        with self.store.default_store(default_ms):
            self.store.create_course('org_x', 'course_y', 'run_z', self.user_id)
            if reset_mixed_mappings:
                self.store.mappings = {}
            with self.assertRaises(DuplicateCourseError):
                self.store.create_course('org_x', 'course_y', 'run_z', self.user_id)

    # Draft:
    #    problem: One lookup to locate an item that exists
    #    fake: one w/ wildcard version
    # split has one lookup for the course and then one for the course items
    @ddt.data(('draft', [1, 1], 0), ('split', [2, 2], 0))
    @ddt.unpack
    def test_has_item(self, default_ms, max_find, max_send):
        self.initdb(default_ms)
        self._create_block_hierarchy()

        self.assertTrue(self.store.has_item(self.course_locations[self.XML_COURSEID1]))

        with check_mongo_calls(max_find.pop(0), max_send):
            self.assertTrue(self.store.has_item(self.problem_x1a_1))

        # try negative cases
        self.assertFalse(self.store.has_item(
            self.course_locations[self.XML_COURSEID1].replace(name='not_findable', category='problem')
        ))
        with check_mongo_calls(max_find.pop(0), max_send):
            self.assertFalse(self.store.has_item(self.fake_location))

        # verify that an error is raised when the revision is not valid
        with self.assertRaises(UnsupportedRevisionError):
            self.store.has_item(self.fake_location, revision=ModuleStoreEnum.RevisionOption.draft_preferred)

    # draft queries:
    #   problem: find draft item, find all items pertinent to inheritance computation
    #   non-existent problem: find draft, find published
    # split:
    #   problem: active_versions, structure
    #   non-existent problem: ditto
    @ddt.data(('draft', [2, 2], 0), ('split', [2, 2], 0))
    @ddt.unpack
    def test_get_item(self, default_ms, max_find, max_send):
        self.initdb(default_ms)
        self._create_block_hierarchy()

        self.assertIsNotNone(self.store.get_item(self.course_locations[self.XML_COURSEID1]))

        with check_mongo_calls(max_find.pop(0), max_send):
            self.assertIsNotNone(self.store.get_item(self.problem_x1a_1))

        # try negative cases
        with self.assertRaises(ItemNotFoundError):
            self.store.get_item(
                self.course_locations[self.XML_COURSEID1].replace(name='not_findable', category='problem')
            )
        with check_mongo_calls(max_find.pop(0), max_send):
            with self.assertRaises(ItemNotFoundError):
                self.store.get_item(self.fake_location)

        # verify that an error is raised when the revision is not valid
        with self.assertRaises(UnsupportedRevisionError):
            self.store.get_item(self.fake_location, revision=ModuleStoreEnum.RevisionOption.draft_preferred)

    # Draft:
    #    wildcard query, 6! load pertinent items for inheritance calls, course root fetch (why)
    # Split:
    #    active_versions (with regex), structure, and spurious active_versions refetch
    @ddt.data(('draft', 8, 0), ('split', 3, 0))
    @ddt.unpack
    def test_get_items(self, default_ms, max_find, max_send):
        self.initdb(default_ms)
        self._create_block_hierarchy()

        course_locn = self.course_locations[self.XML_COURSEID1]
        # NOTE: use get_course if you just want the course. get_items is expensive
        modules = self.store.get_items(course_locn.course_key, qualifiers={'category': 'course'})
        self.assertEqual(len(modules), 1)
        self.assertEqual(modules[0].location, course_locn)

        course_locn = self.course_locations[self.MONGO_COURSEID]
        with check_mongo_calls(max_find, max_send):
            # NOTE: use get_course if you just want the course. get_items is expensive
            modules = self.store.get_items(course_locn.course_key, qualifiers={'category': 'problem'})
        self.assertEqual(len(modules), 6)

        # verify that an error is raised when the revision is not valid
        with self.assertRaises(UnsupportedRevisionError):
            self.store.get_items(
                self.course_locations[self.MONGO_COURSEID].course_key,
                revision=ModuleStoreEnum.RevisionOption.draft_preferred
            )

    # draft: get draft, count parents, get parents, count & get grandparents, count & get greatgrand,
    #        count & get next ancestor (chapter's parent), count non-existent next ancestor, get inheritance
    #    sends: update problem and then each ancestor up to course (edit info)
    # split: active_versions, definitions (calculator field), structures
    #  2 sends to update index & structure (note, it would also be definition if a content field changed)
    @ddt.data(('draft', 11, 5), ('split', 3, 2))
    @ddt.unpack
    def test_update_item(self, default_ms, max_find, max_send):
        """
        Update should fail for r/o dbs and succeed for r/w ones
        """
        self.initdb(default_ms)
        self._create_block_hierarchy()
        course = self.store.get_course(self.course_locations[self.XML_COURSEID1].course_key)
        # if following raised, then the test is really a noop, change it
        self.assertFalse(course.show_calculator, "Default changed making test meaningless")
        course.show_calculator = True
        with self.assertRaises(NotImplementedError):  # ensure it doesn't allow writing
            self.store.update_item(course, self.user_id)

        # now do it for a r/w db
        problem = self.store.get_item(self.problem_x1a_1)
        # if following raised, then the test is really a noop, change it
        self.assertNotEqual(problem.max_attempts, 2, "Default changed making test meaningless")
        problem.max_attempts = 2
        with check_mongo_calls(max_find, max_send):
            problem = self.store.update_item(problem, self.user_id)

        self.assertEqual(problem.max_attempts, 2, "Update didn't persist")

    @ddt.data('draft', 'split')
    def test_has_changes_direct_only(self, default_ms):
        """
        Tests that has_changes() returns false when a new xblock in a direct only category is checked
        """
        self.initdb(default_ms)

        test_course = self.store.create_course('testx', 'GreekHero', 'test_run', self.user_id)

        # Create dummy direct only xblocks
        chapter = self.store.create_item(
            self.user_id,
            test_course.id,
            'chapter',
            block_id='vertical_container'
        )

        # Check that neither xblock has changes
        self.assertFalse(self.store.has_changes(test_course))
        self.assertFalse(self.store.has_changes(chapter))

    @ddt.data('draft', 'split')
    def test_has_changes(self, default_ms):
        """
        Tests that has_changes() only returns true when changes are present
        """
        self.initdb(default_ms)

        test_course = self.store.create_course('testx', 'GreekHero', 'test_run', self.user_id)

        # Create a dummy component to test against
        xblock = self.store.create_item(
            self.user_id,
            test_course.id,
            'vertical',
            block_id='test_vertical'
        )

        # Not yet published, so changes are present
        self.assertTrue(self.store.has_changes(xblock))

        # Publish and verify that there are no unpublished changes
        newXBlock = self.store.publish(xblock.location, self.user_id)
        self.assertFalse(self.store.has_changes(newXBlock))

        # Change the component, then check that there now are changes
        component = self.store.get_item(xblock.location)
        component.display_name = 'Changed Display Name'

        component = self.store.update_item(component, self.user_id)
        self.assertTrue(self.store.has_changes(component))

        # Publish and verify again
        component = self.store.publish(component.location, self.user_id)
        self.assertFalse(self.store.has_changes(component))

    def _has_changes(self, location):
        """
        Helper function that loads the item before calling has_changes
        """
        return self.store.has_changes(self.store.get_item(location))

    def setup_has_changes(self, default_ms):
        """
        Common set up for has_changes tests below.
        Returns a dictionary of useful location maps for testing.
        """
        self.initdb(default_ms)
        self._create_block_hierarchy()

        locations = {
            'grandparent': self.chapter_x,
            'parent_sibling': self.sequential_x2,
            'parent': self.sequential_x1,
            'child_sibling': self.vertical_x1b,
            'child': self.vertical_x1a,
        }

        # Publish the vertical units
        self.store.publish(locations['parent_sibling'], self.user_id)
        self.store.publish(locations['parent'], self.user_id)

        return locations

    @ddt.data('draft', 'split')
    def test_has_changes_ancestors(self, default_ms):
        """
        Tests that has_changes() returns true on ancestors when a child is changed
        """
        locations = self.setup_has_changes(default_ms)

        # Verify that there are no unpublished changes
        for key in locations:
            self.assertFalse(self._has_changes(locations[key]))

        # Change the child
        child = self.store.get_item(locations['child'])
        child.display_name = 'Changed Display Name'
        self.store.update_item(child, self.user_id)

        # All ancestors should have changes, but not siblings
        self.assertTrue(self._has_changes(locations['grandparent']))
        self.assertTrue(self._has_changes(locations['parent']))
        self.assertTrue(self._has_changes(locations['child']))
        self.assertFalse(self._has_changes(locations['parent_sibling']))
        self.assertFalse(self._has_changes(locations['child_sibling']))

        # Publish the unit with changes
        self.store.publish(locations['parent'], self.user_id)

        # Verify that there are no unpublished changes
        for key in locations:
            self.assertFalse(self._has_changes(locations[key]))

    @ddt.data('draft', 'split')
    def test_has_changes_publish_ancestors(self, default_ms):
        """
        Tests that has_changes() returns false after a child is published only if all children are unchanged
        """
        locations = self.setup_has_changes(default_ms)

        # Verify that there are no unpublished changes
        for key in locations:
            self.assertFalse(self._has_changes(locations[key]))

        # Change both children
        child = self.store.get_item(locations['child'])
        child_sibling = self.store.get_item(locations['child_sibling'])
        child.display_name = 'Changed Display Name'
        child_sibling.display_name = 'Changed Display Name'
        self.store.update_item(child, user_id=self.user_id)
        self.store.update_item(child_sibling, user_id=self.user_id)

        # Verify that ancestors have changes
        self.assertTrue(self._has_changes(locations['grandparent']))
        self.assertTrue(self._has_changes(locations['parent']))

        # Publish one child
        self.store.publish(locations['child_sibling'], self.user_id)

        # Verify that ancestors still have changes
        self.assertTrue(self._has_changes(locations['grandparent']))
        self.assertTrue(self._has_changes(locations['parent']))

        # Publish the other child
        self.store.publish(locations['child'], self.user_id)

        # Verify that ancestors now have no changes
        self.assertFalse(self._has_changes(locations['grandparent']))
        self.assertFalse(self._has_changes(locations['parent']))

    @ddt.data('draft', 'split')
    def test_has_changes_add_remove_child(self, default_ms):
        """
        Tests that has_changes() returns true for the parent when a child with changes is added
        and false when that child is removed.
        """
        locations = self.setup_has_changes(default_ms)

        # Test that the ancestors don't have changes
        self.assertFalse(self._has_changes(locations['grandparent']))
        self.assertFalse(self._has_changes(locations['parent']))

        # Create a new child and attach it to parent
        self.store.create_child(
            self.user_id,
            locations['parent'],
            'vertical',
            block_id='new_child',
        )

        # Verify that the ancestors now have changes
        self.assertTrue(self._has_changes(locations['grandparent']))
        self.assertTrue(self._has_changes(locations['parent']))

        # Remove the child from the parent
        parent = self.store.get_item(locations['parent'])
        parent.children = [locations['child'], locations['child_sibling']]
        self.store.update_item(parent, user_id=self.user_id)

        # Verify that ancestors now have no changes
        self.assertFalse(self._has_changes(locations['grandparent']))
        self.assertFalse(self._has_changes(locations['parent']))

    @ddt.data('draft', 'split')
    def test_has_changes_non_direct_only_children(self, default_ms):
        """
        Tests that has_changes() returns true after editing the child of a vertical (both not direct only categories).
        """
        self.initdb(default_ms)

        parent = self.store.create_item(
            self.user_id,
            self.course.id,
            'vertical',
            block_id='parent',
        )
        child = self.store.create_child(
            self.user_id,
            parent.location,
            'html',
            block_id='child',
        )
        self.store.publish(parent.location, self.user_id)

        # Verify that there are no changes
        self.assertFalse(self._has_changes(parent.location))
        self.assertFalse(self._has_changes(child.location))

        # Change the child
        child.display_name = 'Changed Display Name'
        self.store.update_item(child, user_id=self.user_id)

        # Verify that both parent and child have changes
        self.assertTrue(self._has_changes(parent.location))
        self.assertTrue(self._has_changes(child.location))

    @ddt.data('draft', 'split')
    def test_has_changes_missing_child(self, default_ms):
        """
        Tests that has_changes() does not throw an exception when a child doesn't exist.
        """
        self.initdb(default_ms)

        # Create the parent and point it to a fake child
        parent = self.store.create_item(
            self.user_id,
            self.course.id,
            'vertical',
            block_id='parent',
        )
        parent.children += [self.course.id.make_usage_key('vertical', 'does_not_exist')]
        parent = self.store.update_item(parent, self.user_id)

        # Check the parent for changes should return True and not throw an exception
        self.assertTrue(self.store.has_changes(parent))

    # Draft
    #   Find: find parents (definition.children query), get parent, get course (fill in run?),
    #         find parents of the parent (course), get inheritance items,
    #         get item (to delete subtree), get inheritance again.
    #   Sends: delete item, update parent
    # Split
    #   Find: active_versions, 2 structures (published & draft), definition (unnecessary)
    #   Sends: updated draft and published structures and active_versions
    @ddt.data(('draft', 7, 2), ('split', 4, 3))
    @ddt.unpack
    def test_delete_item(self, default_ms, max_find, max_send):
        """
        Delete should reject on r/o db and work on r/w one
        """
        self.initdb(default_ms)
        if default_ms == 'draft' and mongo_uses_error_check(self.store):
            max_find += 1

        # r/o try deleting the chapter (is here to ensure it can't be deleted)
        with self.assertRaises(NotImplementedError):
            self.store.delete_item(self.xml_chapter_location, self.user_id)

        with self.store.branch_setting(ModuleStoreEnum.Branch.draft_preferred, self.writable_chapter_location.course_key):
            with check_mongo_calls(max_find, max_send):
                self.store.delete_item(self.writable_chapter_location, self.user_id)

            # verify it's gone
            with self.assertRaises(ItemNotFoundError):
                self.store.get_item(self.writable_chapter_location)
        # verify it's gone from published too
        with self.assertRaises(ItemNotFoundError):
            self.store.get_item(self.writable_chapter_location, revision=ModuleStoreEnum.RevisionOption.published_only)

    # Draft:
    #    queries: find parent (definition.children), count versions of item, get parent, count grandparents,
    #             inheritance items, draft item, draft child, inheritance
    #    sends: delete draft vertical and update parent
    # Split:
    #    queries: active_versions, draft and published structures, definition (unnecessary)
    #    sends: update published (why?), draft, and active_versions
    @ddt.data(('draft', 8, 2), ('split', 2, 2))
    @ddt.unpack
    def test_delete_private_vertical(self, default_ms, max_find, max_send):
        """
        Because old mongo treated verticals as the first layer which could be draft, it has some interesting
        behavioral properties which this deletion test gets at.
        """
        self.initdb(default_ms)
        if default_ms == 'draft' and mongo_uses_error_check(self.store):
            max_find += 1
        # create and delete a private vertical with private children
        private_vert = self.store.create_child(
            # don't use course_location as it may not be the repr
            self.user_id, self.course_locations[self.MONGO_COURSEID],
            'vertical', block_id='private'
        )
        private_leaf = self.store.create_child(
            # don't use course_location as it may not be the repr
            self.user_id, private_vert.location, 'html', block_id='private_leaf'
        )

        # verify pre delete state (just to verify that the test is valid)
        if hasattr(private_vert.location, 'version_guid'):
            # change to the HEAD version
            vert_loc = private_vert.location.for_version(private_leaf.location.version_guid)
        else:
            vert_loc = private_vert.location
        self.assertTrue(self.store.has_item(vert_loc))
        self.assertTrue(self.store.has_item(private_leaf.location))
        course = self.store.get_course(self.course_locations[self.MONGO_COURSEID].course_key, 0)
        self.assertIn(vert_loc, course.children)

        # delete the vertical and ensure the course no longer points to it
        with check_mongo_calls(max_find, max_send):
            self.store.delete_item(vert_loc, self.user_id)
        course = self.store.get_course(self.course_locations[self.MONGO_COURSEID].course_key, 0)
        if hasattr(private_vert.location, 'version_guid'):
            # change to the HEAD version
            vert_loc = private_vert.location.for_version(course.location.version_guid)
            leaf_loc = private_leaf.location.for_version(course.location.version_guid)
        else:
            vert_loc = private_vert.location
            leaf_loc = private_leaf.location
        self.assertFalse(self.store.has_item(vert_loc))
        self.assertFalse(self.store.has_item(leaf_loc))
        self.assertNotIn(vert_loc, course.children)

    # Draft:
    #   find: find parent (definition.children) 2x, find draft item, get inheritance items
    #   send: one delete query for specific item
    # Split:
    #   find: active_version & structure
    #   send: update structure and active_versions
    @ddt.data(('draft', 4, 1), ('split', 2, 2))
    @ddt.unpack
    def test_delete_draft_vertical(self, default_ms, max_find, max_send):
        """
        Test deleting a draft vertical which has a published version.
        """
        self.initdb(default_ms)

        # reproduce bug STUD-1965
        # create and delete a private vertical with private children
        private_vert = self.store.create_child(
            # don't use course_location as it may not be the repr
            self.user_id, self.course_locations[self.MONGO_COURSEID], 'vertical', block_id='publish'
        )
        private_leaf = self.store.create_child(
            self.user_id, private_vert.location, 'html', block_id='bug_leaf'
        )

        # verify that an error is raised when the revision is not valid
        with self.assertRaises(UnsupportedRevisionError):
            self.store.delete_item(
                private_leaf.location,
                self.user_id,
                revision=ModuleStoreEnum.RevisionOption.draft_preferred
            )

        self.store.publish(private_vert.location, self.user_id)
        private_leaf.display_name = 'change me'
        private_leaf = self.store.update_item(private_leaf, self.user_id)
        # test succeeds if delete succeeds w/o error
        if default_ms == 'draft' and mongo_uses_error_check(self.store):
            max_find += 1
        with check_mongo_calls(max_find, max_send):
            self.store.delete_item(private_leaf.location, self.user_id)

    # Draft:
    #   1) find all courses (wildcard),
    #   2) get each course 1 at a time (1 course),
    #   3) wildcard split if it has any (1) but it doesn't
    # Split:
    #   1) wildcard split search,
    #   2-4) active_versions, structure, definition (s/b lazy; so, unnecessary)
    #   5) wildcard draft mongo which has none
    @ddt.data(('draft', 3, 0), ('split', 5, 0))
    @ddt.unpack
    def test_get_courses(self, default_ms, max_find, max_send):
        self.initdb(default_ms)
        # we should have 3 total courses across all stores
        with check_mongo_calls(max_find, max_send):
            courses = self.store.get_courses()
            course_ids = [course.location for course in courses]
            self.assertEqual(len(courses), 3, "Not 3 courses: {}".format(course_ids))
            self.assertIn(self.course_locations[self.MONGO_COURSEID], course_ids)
            self.assertIn(self.course_locations[self.XML_COURSEID1], course_ids)
            self.assertIn(self.course_locations[self.XML_COURSEID2], course_ids)

        with self.store.branch_setting(ModuleStoreEnum.Branch.draft_preferred):
            draft_courses = self.store.get_courses(remove_branch=True)
        with self.store.branch_setting(ModuleStoreEnum.Branch.published_only):
            published_courses = self.store.get_courses(remove_branch=True)
        self.assertEquals([c.id for c in draft_courses], [c.id for c in published_courses])

    def test_xml_get_courses(self):
        """
        Test that the xml modulestore only loaded the courses from the maps.
        """
        self.initdb('draft')
        xml_store = self.store._get_modulestore_by_type(ModuleStoreEnum.Type.xml)  # pylint: disable=protected-access
        courses = xml_store.get_courses()
        self.assertEqual(len(courses), 2)
        course_ids = [course.id for course in courses]
        self.assertIn(self.course_locations[self.XML_COURSEID1].course_key, course_ids)
        self.assertIn(self.course_locations[self.XML_COURSEID2].course_key, course_ids)
        # this course is in the directory from which we loaded courses but not in the map
        self.assertNotIn("edX/toy/TT_2012_Fall", course_ids)

    def test_xml_no_write(self):
        """
        Test that the xml modulestore doesn't allow write ops.
        """
        self.initdb('draft')
        xml_store = self.store._get_modulestore_by_type(ModuleStoreEnum.Type.xml)  # pylint: disable=protected-access
        # the important thing is not which exception it raises but that it raises an exception
        with self.assertRaises(AttributeError):
            xml_store.create_course("org", "course", "run", self.user_id)

    # draft is 2: find out which ms owns course, get item
    # split: active_versions, structure, definition (to load course wiki string)
    @ddt.data(('draft', 2, 0), ('split', 3, 0))
    @ddt.unpack
    def test_get_course(self, default_ms, max_find, max_send):
        """
        This test is here for the performance comparison not functionality. It tests the performance
        of getting an item whose scope.content fields are looked at.
        """
        self.initdb(default_ms)
        with check_mongo_calls(max_find, max_send):
            course = self.store.get_item(self.course_locations[self.MONGO_COURSEID])
            self.assertEqual(course.id, self.course_locations[self.MONGO_COURSEID].course_key)

        course = self.store.get_item(self.course_locations[self.XML_COURSEID1])
        self.assertEqual(course.id, self.course_locations[self.XML_COURSEID1].course_key)

    # notice this doesn't test getting a public item via draft_preferred which draft would have 2 hits (split
    # still only 2)
    # Draft: count via definition.children query, then fetch via that query
    # Split: active_versions, structure
    @ddt.data(('draft', 2, 0), ('split', 2, 0))
    @ddt.unpack
    def test_get_parent_locations(self, default_ms, max_find, max_send):
        """
        Test a simple get parent for a direct only category (i.e, always published)
        """
        self.initdb(default_ms)
        self._create_block_hierarchy()

        with check_mongo_calls(max_find, max_send):
            parent = self.store.get_parent_location(self.problem_x1a_1)
            self.assertEqual(parent, self.vertical_x1a)

        parent = self.store.get_parent_location(self.xml_chapter_location)
        self.assertEqual(parent, self.course_locations[self.XML_COURSEID1])

    def verify_get_parent_locations_results(self, expected_results):
        """
        Verifies the results of calling get_parent_locations matches expected_results.
        """
        for child_location, parent_location, revision in expected_results:
            self.assertEqual(
                parent_location,
                self.store.get_parent_location(child_location, revision=revision)
            )

    @ddt.data('draft', 'split')
    def test_get_parent_locations_moved_child(self, default_ms):
        self.initdb(default_ms)
        self._create_block_hierarchy()

        # publish the course
        self.course = self.store.publish(self.course.location, self.user_id)

        # make drafts of verticals
        self.store.convert_to_draft(self.vertical_x1a, self.user_id)
        self.store.convert_to_draft(self.vertical_y1a, self.user_id)

        # move child problem_x1a_1 to vertical_y1a
        child_to_move_location = self.problem_x1a_1
        new_parent_location = self.vertical_y1a
        old_parent_location = self.vertical_x1a

        old_parent = self.store.get_item(old_parent_location)
        old_parent.children.remove(child_to_move_location.replace(version_guid=old_parent.location.version_guid))
        self.store.update_item(old_parent, self.user_id)

        new_parent = self.store.get_item(new_parent_location)
        new_parent.children.append(child_to_move_location.replace(version_guid=new_parent.location.version_guid))
        self.store.update_item(new_parent, self.user_id)

        self.verify_get_parent_locations_results([
            (child_to_move_location, new_parent_location, None),
            (child_to_move_location, new_parent_location, ModuleStoreEnum.RevisionOption.draft_preferred),
            (child_to_move_location, old_parent_location.for_branch(ModuleStoreEnum.BranchName.published), ModuleStoreEnum.RevisionOption.published_only),
        ])

        # publish the course again
        self.store.publish(self.course.location, self.user_id)
        self.verify_get_parent_locations_results([
            (child_to_move_location, new_parent_location, None),
            (child_to_move_location, new_parent_location, ModuleStoreEnum.RevisionOption.draft_preferred),
            (child_to_move_location, new_parent_location.for_branch(ModuleStoreEnum.BranchName.published), ModuleStoreEnum.RevisionOption.published_only),
        ])

    @ddt.data('draft')
    def test_get_parent_locations_deleted_child(self, default_ms):
        self.initdb(default_ms)
        self._create_block_hierarchy()

        # publish the course
        self.store.publish(self.course.location, self.user_id)

        # make draft of vertical
        self.store.convert_to_draft(self.vertical_y1a, self.user_id)

        # delete child problem_y1a_1
        child_to_delete_location = self.problem_y1a_1
        old_parent_location = self.vertical_y1a
        self.store.delete_item(child_to_delete_location, self.user_id)

        self.verify_get_parent_locations_results([
            (child_to_delete_location, old_parent_location, None),
            # Note: The following could be an unexpected result, but we want to avoid an extra database call
            (child_to_delete_location, old_parent_location, ModuleStoreEnum.RevisionOption.draft_preferred),
            (child_to_delete_location, old_parent_location, ModuleStoreEnum.RevisionOption.published_only),
        ])

        # publish the course again
        self.store.publish(self.course.location, self.user_id)
        self.verify_get_parent_locations_results([
            (child_to_delete_location, None, None),
            (child_to_delete_location, None, ModuleStoreEnum.RevisionOption.draft_preferred),
            (child_to_delete_location, None, ModuleStoreEnum.RevisionOption.published_only),
        ])

    # Draft:
    #   Problem path:
    #    1. Get problem
    #    2-3. count matches definition.children called 2x?
    #    4. get parent via definition.children query
    #    5-7. 2 counts and 1 get grandparent via definition.children
    #    8-10. ditto for great-grandparent
    #    11-13. ditto for next ancestor
    #    14. fail count query looking for parent of course (unnecessary)
    #    15. get course record direct query (not via definition.children) (already fetched in 13)
    #    16. get items for inheritance computation
    #    17. get vertical (parent of problem)
    #    18. get items for inheritance computation (why? caching should handle)
    #    19-20. get vertical_x1b (? why? this is the only ref in trace) & items for inheritance computation
    #   Chapter path: get chapter, count parents 2x, get parents, count non-existent grandparents
    # Split: active_versions & structure
    @ddt.data(('draft', [20, 5], 0), ('split', [2, 2], 0))
    @ddt.unpack
    def test_path_to_location(self, default_ms, num_finds, num_sends):
        """
        Make sure that path_to_location works
        """
        self.initdb(default_ms)

        course_key = self.course_locations[self.MONGO_COURSEID].course_key
        with self.store.branch_setting(ModuleStoreEnum.Branch.published_only, course_key):
            self._create_block_hierarchy()

            should_work = (
                (self.problem_x1a_2,
                 (course_key, u"Chapter_x", u"Sequential_x1", '1')),
                (self.chapter_x,
                 (course_key, "Chapter_x", None, None)),
            )

            for location, expected in should_work:
                # each iteration has different find count, pop this iter's find count
                with check_mongo_calls(num_finds.pop(0), num_sends):
                    self.assertEqual(path_to_location(self.store, location), expected)

        not_found = (
            course_key.make_usage_key('video', 'WelcomeX'),
            course_key.make_usage_key('course', 'NotHome'),
        )
        for location in not_found:
            with self.assertRaises(ItemNotFoundError):
                path_to_location(self.store, location)

        # Orphaned items should not be found.
        orphan = course_key.make_usage_key('chapter', 'OrphanChapter')
        self.store.create_item(
            self.user_id,
            orphan.course_key,
            orphan.block_type,
            block_id=orphan.block_id
        )

        with self.assertRaises(NoPathToItem):
            path_to_location(self.store, orphan)

    def test_xml_path_to_location(self):
        """
        Make sure that path_to_location works: should be passed a modulestore
        with the toy and simple courses loaded.
        """
        # only needs course_locations set
        self.initdb('draft')
        course_key = self.course_locations[self.XML_COURSEID1].course_key
        should_work = (
            (course_key.make_usage_key('video', 'Welcome'),
             (course_key, "Overview", "Welcome", None)),
            (course_key.make_usage_key('chapter', 'Overview'),
             (course_key, "Overview", None, None)),
        )

        for location, expected in should_work:
            self.assertEqual(path_to_location(self.store, location), expected)

        not_found = (
            course_key.make_usage_key('video', 'WelcomeX'),
            course_key.make_usage_key('course', 'NotHome'),
        )
        for location in not_found:
            with self.assertRaises(ItemNotFoundError):
                path_to_location(self.store, location)

    @ddt.data('draft', 'split')
    def test_revert_to_published_root_draft(self, default_ms):
        """
        Test calling revert_to_published on draft vertical.
        """
        self.initdb(default_ms)
        self._create_block_hierarchy()

        vertical = self.store.get_item(self.vertical_x1a)
        vertical_children_num = len(vertical.children)

        self.store.publish(self.course.location, self.user_id)
        self.assertFalse(self._has_changes(self.vertical_x1a))

        # delete leaf problem (will make parent vertical a draft)
        self.store.delete_item(self.problem_x1a_1, self.user_id)
        self.assertTrue(self._has_changes(self.vertical_x1a))

        draft_parent = self.store.get_item(self.vertical_x1a)
        self.assertEqual(vertical_children_num - 1, len(draft_parent.children))
        published_parent = self.store.get_item(
            self.vertical_x1a,
            revision=ModuleStoreEnum.RevisionOption.published_only
        )
        self.assertEqual(vertical_children_num, len(published_parent.children))

        self.store.revert_to_published(self.vertical_x1a, self.user_id)
        reverted_parent = self.store.get_item(self.vertical_x1a)
        self.assertEqual(vertical_children_num, len(published_parent.children))
        self.assertBlocksEqualByFields(reverted_parent, published_parent)
        self.assertFalse(self._has_changes(self.vertical_x1a))

    @ddt.data('draft', 'split')
    def test_revert_to_published_root_published(self, default_ms):
        """
        Test calling revert_to_published on a published vertical with a draft child.
        """
        self.initdb(default_ms)
        self._create_block_hierarchy()
        self.store.publish(self.course.location, self.user_id)

        problem = self.store.get_item(self.problem_x1a_1)
        orig_display_name = problem.display_name

        # Change display name of problem and update just it (so parent remains published)
        problem.display_name = "updated before calling revert"
        self.store.update_item(problem, self.user_id)
        self.store.revert_to_published(self.vertical_x1a, self.user_id)

        reverted_problem = self.store.get_item(self.problem_x1a_1)
        self.assertEqual(orig_display_name, reverted_problem.display_name)

    @ddt.data('draft', 'split')
    def test_revert_to_published_no_draft(self, default_ms):
        """
        Test calling revert_to_published on vertical with no draft content does nothing.
        """
        self.initdb(default_ms)
        self._create_block_hierarchy()
        self.store.publish(self.course.location, self.user_id)

        orig_vertical = self.store.get_item(self.vertical_x1a)
        self.store.revert_to_published(self.vertical_x1a, self.user_id)
        reverted_vertical = self.store.get_item(self.vertical_x1a)

        self.assertBlocksEqualByFields(orig_vertical, reverted_vertical)

    @ddt.data('draft', 'split')
    def test_revert_to_published_no_published(self, default_ms):
        """
        Test calling revert_to_published on vertical with no published version errors.
        """
        self.initdb(default_ms)
        self._create_block_hierarchy()
        with self.assertRaises(InvalidVersionError):
            self.store.revert_to_published(self.vertical_x1a, self.user_id)

    @ddt.data('draft', 'split')
    def test_revert_to_published_direct_only(self, default_ms):
        """
        Test calling revert_to_published on a direct-only item is a no-op.
        """
        self.initdb(default_ms)
        self._create_block_hierarchy()
        num_children = len(self.store.get_item(self.sequential_x1).children)
        self.store.revert_to_published(self.sequential_x1, self.user_id)
        reverted_parent = self.store.get_item(self.sequential_x1)
        # It does not discard the child vertical, even though that child is a draft (with no published version)
        self.assertEqual(num_children, len(reverted_parent.children))

    # Draft: get all items which can be or should have parents
    # Split: active_versions, structure
    @ddt.data(('draft', 1, 0), ('split', 2, 0))
    @ddt.unpack
    def test_get_orphans(self, default_ms, max_find, max_send):
        """
        Test finding orphans.
        """
        self.initdb(default_ms)
        course_id = self.course_locations[self.MONGO_COURSEID].course_key

        # create parented children
        self._create_block_hierarchy()

        # orphans
        orphan_locations = [
            course_id.make_usage_key('chapter', 'OrphanChapter'),
            course_id.make_usage_key('vertical', 'OrphanVertical'),
            course_id.make_usage_key('problem', 'OrphanProblem'),
            course_id.make_usage_key('html', 'OrphanHTML'),
        ]

        # detached items (not considered as orphans)
        detached_locations = [
            course_id.make_usage_key('static_tab', 'StaticTab'),
            course_id.make_usage_key('course_info', 'updates'),
        ]

        for location in (orphan_locations + detached_locations):
            self.store.create_item(
                self.user_id,
                location.course_key,
                location.block_type,
                block_id=location.block_id
            )

        with check_mongo_calls(max_find, max_send):
            found_orphans = self.store.get_orphans(self.course_locations[self.MONGO_COURSEID].course_key)
        self.assertItemsEqual(found_orphans, orphan_locations)

    @ddt.data('draft')
    def test_get_non_orphan_parents(self, default_ms):
        """
        Test finding non orphan parents from many possible parents.
        """
        self.initdb(default_ms)
        course_id = self.course_locations[self.MONGO_COURSEID].course_key

        # create parented children
        self._create_block_hierarchy()
        self.store.publish(self.course.location, self.user_id)

        # test that problem "problem_x1a_1" has only one published parent
        mongo_store = self.store._get_modulestore_for_courseid(course_id)  # pylint: disable=protected-access
        with self.store.branch_setting(ModuleStoreEnum.Branch.published_only, course_id):
            parent = mongo_store.get_parent_location(self.problem_x1a_1)
            self.assertEqual(parent, self.vertical_x1a)

        # add some published orphans
        orphan_sequential = course_id.make_usage_key('sequential', 'OrphanSequential')
        orphan_vertical = course_id.make_usage_key('vertical', 'OrphanVertical')
        orphan_locations = [orphan_sequential, orphan_vertical]
        for location in orphan_locations:
            self.store.create_item(
                self.user_id,
                location.course_key,
                location.block_type,
                block_id=location.block_id
            )
            self.store.publish(location, self.user_id)

        found_orphans = mongo_store.get_orphans(course_id)
        self.assertEqual(set(found_orphans), set(orphan_locations))
        self.assertEqual(len(set(found_orphans)), 2)

        # add orphan vertical and sequential as another parents of problem "problem_x1a_1"
        mongo_store.collection.update(
            orphan_sequential.to_deprecated_son('_id.'),
            {'$push': {'definition.children': unicode(self.problem_x1a_1)}}
        )
        mongo_store.collection.update(
            orphan_vertical.to_deprecated_son('_id.'),
            {'$push': {'definition.children': unicode(self.problem_x1a_1)}}
        )
        # test that "get_parent_location" method of published branch still returns the correct non-orphan parent for
        # problem "problem_x1a_1" since the two other parents are orphans
        with self.store.branch_setting(ModuleStoreEnum.Branch.published_only, course_id):
            parent = mongo_store.get_parent_location(self.problem_x1a_1)
            self.assertEqual(parent, self.vertical_x1a)

        # now add valid published vertical as another parent of problem
        mongo_store.collection.update(
            self.sequential_x1.to_deprecated_son('_id.'),
            {'$push': {'definition.children': unicode(self.problem_x1a_1)}}
        )
        # now check that "get_parent_location" method of published branch raises "ReferentialIntegrityError" for
        # problem "problem_x1a_1" since it has now 2 valid published parents
        with self.store.branch_setting(ModuleStoreEnum.Branch.published_only, course_id):
            self.assertTrue(self.store.has_item(self.problem_x1a_1))
            with self.assertRaises(ReferentialIntegrityError):
                self.store.get_parent_location(self.problem_x1a_1)

    @ddt.data('draft')
    def test_create_item_from_parent_location(self, default_ms):
        """
        Test a code path missed by the above: passing an old-style location as parent but no
        new location for the child
        """
        self.initdb(default_ms)
        self.store.create_child(
            self.user_id,
            self.course_locations[self.MONGO_COURSEID],
            'problem',
            block_id='orphan'
        )
        orphans = self.store.get_orphans(self.course_locations[self.MONGO_COURSEID].course_key)
        self.assertEqual(len(orphans), 0, "unexpected orphans: {}".format(orphans))

    @ddt.data('draft', 'split')
    def test_create_item_populates_edited_info(self, default_ms):
        self.initdb(default_ms)
        block = self.store.create_item(
            self.user_id,
            self.course.location.course_key,
            'problem'
        )
        self.assertEqual(self.user_id, block.edited_by)
        self.assertGreater(datetime.datetime.now(UTC), block.edited_on)

    @ddt.data('draft', 'split')
    def test_create_item_populates_subtree_edited_info(self, default_ms):
        self.initdb(default_ms)
        block = self.store.create_item(
            self.user_id,
            self.course.location.course_key,
            'problem'
        )
        self.assertEqual(self.user_id, block.subtree_edited_by)
        self.assertGreater(datetime.datetime.now(UTC), block.subtree_edited_on)

    # Draft: wildcard search of draft and split
    # Split: wildcard search of draft and split
    @ddt.data(('draft', 2, 0), ('split', 2, 0))
    @ddt.unpack
    def test_get_courses_for_wiki(self, default_ms, max_find, max_send):
        """
        Test the get_courses_for_wiki method
        """
        self.initdb(default_ms)
        # Test XML wikis
        wiki_courses = self.store.get_courses_for_wiki('toy')
        self.assertEqual(len(wiki_courses), 1)
        self.assertIn(self.course_locations[self.XML_COURSEID1].course_key, wiki_courses)

        wiki_courses = self.store.get_courses_for_wiki('simple')
        self.assertEqual(len(wiki_courses), 1)
        self.assertIn(self.course_locations[self.XML_COURSEID2].course_key, wiki_courses)

        # Test Mongo wiki
        with check_mongo_calls(max_find, max_send):
            wiki_courses = self.store.get_courses_for_wiki('999')
        self.assertEqual(len(wiki_courses), 1)
        self.assertIn(
            self.course_locations[self.MONGO_COURSEID].course_key.replace(branch=None),  # Branch agnostic
            wiki_courses
        )

        self.assertEqual(len(self.store.get_courses_for_wiki('edX.simple.2012_Fall')), 0)
        self.assertEqual(len(self.store.get_courses_for_wiki('no_such_wiki')), 0)

    # Draft:
    #    Find: find vertical, find children
    #    Sends:
    #      1. delete all of the published nodes in subtree
    #      2. insert vertical as published (deleted in step 1) w/ the deleted problems as children
    #      3-6. insert the 3 problems and 1 html as published
    # Split: active_versions, 2 structures (pre & post published?)
    # Sends:
    #    - insert structure
    #    - write index entry
    @ddt.data(('draft', 2, 6), ('split', 3, 2))
    @ddt.unpack
    def test_unpublish(self, default_ms, max_find, max_send):
        """
        Test calling unpublish
        """
        self.initdb(default_ms)
        if default_ms == 'draft' and mongo_uses_error_check(self.store):
            max_find += 1
        self._create_block_hierarchy()

        # publish
        self.store.publish(self.course.location, self.user_id)
        published_xblock = self.store.get_item(
            self.vertical_x1a,
            revision=ModuleStoreEnum.RevisionOption.published_only
        )
        self.assertIsNotNone(published_xblock)

        # unpublish
        with check_mongo_calls(max_find, max_send):
            self.store.unpublish(self.vertical_x1a, self.user_id)

        with self.assertRaises(ItemNotFoundError):
            self.store.get_item(
                self.vertical_x1a,
                revision=ModuleStoreEnum.RevisionOption.published_only
            )

        # make sure draft version still exists
        draft_xblock = self.store.get_item(
            self.vertical_x1a,
            revision=ModuleStoreEnum.RevisionOption.draft_only
        )
        self.assertIsNotNone(draft_xblock)

    # Draft: specific query for revision None
    # Split: active_versions, structure
    @ddt.data(('draft', 1, 0), ('split', 2, 0))
    @ddt.unpack
    def test_has_published_version(self, default_ms, max_find, max_send):
        """
        Test the has_published_version method
        """
        self.initdb(default_ms)
        self._create_block_hierarchy()

        # start off as Private
        item = self.store.create_child(self.user_id, self.writable_chapter_location, 'problem', 'test_compute_publish_state')
        item_location = item.location
        with check_mongo_calls(max_find, max_send):
            self.assertFalse(self.store.has_published_version(item))

        # Private -> Public
        self.store.publish(item_location, self.user_id)
        item = self.store.get_item(item_location)
        self.assertTrue(self.store.has_published_version(item))

        # Public -> Private
        self.store.unpublish(item_location, self.user_id)
        item = self.store.get_item(item_location)
        self.assertFalse(self.store.has_published_version(item))

        # Private -> Public
        self.store.publish(item_location, self.user_id)
        item = self.store.get_item(item_location)
        self.assertTrue(self.store.has_published_version(item))

        # Public -> Draft with NO changes
        self.store.convert_to_draft(item_location, self.user_id)
        item = self.store.get_item(item_location)
        self.assertTrue(self.store.has_published_version(item))

        # Draft WITH changes
        item.display_name = 'new name'
        item = self.store.update_item(item, self.user_id)
        self.assertTrue(self.store.has_changes(item))
        self.assertTrue(self.store.has_published_version(item))

    @ddt.data('draft', 'split')
    def test_update_edit_info_ancestors(self, default_ms):
        """
        Tests that edited_on, edited_by, subtree_edited_on, and subtree_edited_by are set correctly during update
        """
        self.initdb(default_ms)

        test_course = self.store.create_course('testx', 'GreekHero', 'test_run', self.user_id)

        def check_node(location_key, after, before, edited_by, subtree_after, subtree_before, subtree_by):
            """
            Checks that the node given by location_key matches the given edit_info constraints.
            """
            node = self.store.get_item(location_key)
            if after:
                self.assertLess(after, node.edited_on)
            self.assertLess(node.edited_on, before)
            self.assertEqual(node.edited_by, edited_by)
            if subtree_after:
                self.assertLess(subtree_after, node.subtree_edited_on)
            self.assertLess(node.subtree_edited_on, subtree_before)
            self.assertEqual(node.subtree_edited_by, subtree_by)

        with self.store.bulk_operations(test_course.id):
            # Create a dummy vertical & html to test against
            component = self.store.create_child(
                self.user_id,
                test_course.location,
                'vertical',
                block_id='test_vertical'
            )
            child = self.store.create_child(
                self.user_id,
                component.location,
                'html',
                block_id='test_html'
            )
            sibling = self.store.create_child(
                self.user_id,
                component.location,
                'html',
                block_id='test_html_no_change'
            )

        after_create = datetime.datetime.now(UTC)
        # Verify that all nodes were last edited in the past by create_user
        for block in [component, child, sibling]:
            check_node(block.location, None, after_create, self.user_id, None, after_create, self.user_id)

        # Change the component, then check that there now are changes
        component.display_name = 'Changed Display Name'

        editing_user = self.user_id - 2
        with self.store.bulk_operations(test_course.id):  # TNL-764 bulk ops disabled ancestor updates
            component = self.store.update_item(component, editing_user)
        after_edit = datetime.datetime.now(UTC)
        check_node(component.location, after_create, after_edit, editing_user, after_create, after_edit, editing_user)
        # but child didn't change
        check_node(child.location, None, after_create, self.user_id, None, after_create, self.user_id)

        # Change the child
        child = self.store.get_item(child.location)
        child.display_name = 'Changed Display Name'
        self.store.update_item(child, user_id=editing_user)

        after_edit = datetime.datetime.now(UTC)

        # Verify that child was last edited between after_create and after_edit by edit_user
        check_node(child.location, after_create, after_edit, editing_user, after_create, after_edit, editing_user)

        # Verify that ancestors edit info is unchanged, but their subtree edit info matches child
        check_node(test_course.location, None, after_create, self.user_id, after_create, after_edit, editing_user)

        # Verify that others have unchanged edit info
        check_node(sibling.location, None, after_create, self.user_id, None, after_create, self.user_id)

    @ddt.data('draft', 'split')
    def test_update_edit_info(self, default_ms):
        """
        Tests that edited_on and edited_by are set correctly during an update
        """
        self.initdb(default_ms)

        test_course = self.store.create_course('testx', 'GreekHero', 'test_run', self.user_id)

        # Create a dummy component to test against
        component = self.store.create_child(
            self.user_id,
            test_course.location,
            'vertical',
        )

        # Store the current edit time and verify that user created the component
        self.assertEqual(component.edited_by, self.user_id)
        old_edited_on = component.edited_on

        edit_user = self.user_id - 2
        # Change the component
        component.display_name = 'Changed'
        self.store.update_item(component, edit_user)
        updated_component = self.store.get_item(component.location)

        # Verify the ordering of edit times and that dummy_user made the edit
        self.assertLess(old_edited_on, updated_component.edited_on)
        self.assertEqual(updated_component.edited_by, edit_user)

    @ddt.data('draft', 'split')
    def test_update_published_info(self, default_ms):
        """
        Tests that published_on and published_by are set correctly
        """
        self.initdb(default_ms)

        test_course = self.store.create_course('testx', 'GreekHero', 'test_run', self.user_id)

        publish_user = 456

        # Create a dummy component to test against
        component = self.store.create_child(
            self.user_id,
            test_course.location,
            'vertical',
        )

        # Store the current time, then publish
        old_time = datetime.datetime.now(UTC)
        self.store.publish(component.location, publish_user)
        updated_component = self.store.get_item(component.location)

        # Verify the time order and that publish_user caused publication
        self.assertLessEqual(old_time, updated_component.published_on)
        self.assertEqual(updated_component.published_by, publish_user)

        # Verify that changing the item doesn't unset the published info
        updated_component.display_name = 'changed'
        self.store.update_item(updated_component, self.user_id)
        updated_component = self.store.get_item(updated_component.location)
        self.assertLessEqual(old_time, updated_component.published_on)
        self.assertEqual(updated_component.published_by, publish_user)

    @ddt.data('draft', 'split')
    def test_auto_publish(self, default_ms):
        """
        Test that the correct things have been published automatically
        Assumptions:
            * we auto-publish courses, chapters, sequentials
            * we don't auto-publish problems
        """

        self.initdb(default_ms)

        # test create_course to make sure we are autopublishing
        test_course = self.store.create_course('testx', 'GreekHero', 'test_run', self.user_id)
        self.assertTrue(self.store.has_published_version(test_course))

        test_course_key = test_course.id

        # test create_item of direct-only category to make sure we are autopublishing
        chapter = self.store.create_child(self.user_id, test_course.location, 'chapter', 'Overview')
        with self.store.branch_setting(ModuleStoreEnum.Branch.published_only):
            self.assertIn(
                chapter.location,
                self.store.get_item(test_course.location).children,
            )
        self.assertTrue(self.store.has_published_version(chapter))

        chapter_location = chapter.location

        # test create_child of direct-only category to make sure we are autopublishing
        sequential = self.store.create_child(self.user_id, chapter_location, 'sequential', 'Sequence')
        with self.store.branch_setting(ModuleStoreEnum.Branch.published_only):
            self.assertIn(
                sequential.location,
                self.store.get_item(chapter_location).children,
            )
        self.assertTrue(self.store.has_published_version(sequential))

        # test update_item of direct-only category to make sure we are autopublishing
        sequential.display_name = 'sequential1'
        sequential = self.store.update_item(sequential, self.user_id)
        self.assertTrue(self.store.has_published_version(sequential))

        # test delete_item of direct-only category to make sure we are autopublishing
        self.store.delete_item(sequential.location, self.user_id, revision=ModuleStoreEnum.RevisionOption.all)
        with self.store.branch_setting(ModuleStoreEnum.Branch.published_only):
            self.assertNotIn(
                sequential.location,
                self.store.get_item(chapter_location).children,
            )
        chapter = self.store.get_item(chapter.location.for_branch(None))
        self.assertTrue(self.store.has_published_version(chapter))

        # test create_child of NOT direct-only category to make sure we aren't autopublishing
        problem_child = self.store.create_child(self.user_id, chapter_location, 'problem', 'Problem_Child')
        self.assertFalse(self.store.has_published_version(problem_child))

        # test create_item of NOT direct-only category to make sure we aren't autopublishing
        problem_item = self.store.create_item(self.user_id, test_course_key, 'problem', 'Problem_Item')
        self.assertFalse(self.store.has_published_version(problem_item))

        # test update_item of NOT direct-only category to make sure we aren't autopublishing
        problem_item.display_name = 'Problem_Item1'
        problem_item = self.store.update_item(problem_item, self.user_id)
        self.assertFalse(self.store.has_published_version(problem_item))

        # test delete_item of NOT direct-only category to make sure we aren't autopublishing
        self.store.delete_item(problem_child.location, self.user_id)
        chapter = self.store.get_item(chapter.location.for_branch(None))
        self.assertTrue(self.store.has_published_version(chapter))

    @ddt.data('draft', 'split')
    def test_get_courses_for_wiki_shared(self, default_ms):
        """
        Test two courses sharing the same wiki
        """
        self.initdb(default_ms)

        # verify initial state - initially, we should have a wiki for the Mongo course
        wiki_courses = self.store.get_courses_for_wiki('999')
        self.assertIn(
            self.course_locations[self.MONGO_COURSEID].course_key.replace(branch=None),  # Branch agnostic
            wiki_courses
        )

        # set Mongo course to share the wiki with simple course
        mongo_course = self.store.get_course(self.course_locations[self.MONGO_COURSEID].course_key)
        mongo_course.wiki_slug = 'simple'
        self.store.update_item(mongo_course, self.user_id)

        # now mongo_course should not be retrievable with old wiki_slug
        wiki_courses = self.store.get_courses_for_wiki('999')
        self.assertEqual(len(wiki_courses), 0)

        # but there should be two courses with wiki_slug 'simple'
        wiki_courses = self.store.get_courses_for_wiki('simple')
        self.assertEqual(len(wiki_courses), 2)
        self.assertIn(
            self.course_locations[self.MONGO_COURSEID].course_key.replace(branch=None),
            wiki_courses
        )
        self.assertIn(self.course_locations[self.XML_COURSEID2].course_key, wiki_courses)

        # configure mongo course to use unique wiki_slug.
        mongo_course = self.store.get_course(self.course_locations[self.MONGO_COURSEID].course_key)
        mongo_course.wiki_slug = 'MITx.999.2013_Spring'
        self.store.update_item(mongo_course, self.user_id)
        # it should be retrievable with its new wiki_slug
        wiki_courses = self.store.get_courses_for_wiki('MITx.999.2013_Spring')
        self.assertEqual(len(wiki_courses), 1)
        self.assertIn(
            self.course_locations[self.MONGO_COURSEID].course_key.replace(branch=None),
            wiki_courses
        )
        # and NOT retriveable with its old wiki_slug
        wiki_courses = self.store.get_courses_for_wiki('simple')
        self.assertEqual(len(wiki_courses), 1)
        self.assertNotIn(
            self.course_locations[self.MONGO_COURSEID].course_key.replace(branch=None),
            wiki_courses
        )
        self.assertIn(
            self.course_locations[self.XML_COURSEID2].course_key,
            wiki_courses
        )

    @ddt.data('draft', 'split')
    def test_branch_setting(self, default_ms):
        """
        Test the branch_setting context manager
        """
        self.initdb(default_ms)
        self._create_block_hierarchy()

        problem_location = self.problem_x1a_1.for_branch(None)
        problem_original_name = 'Problem_x1a_1'

        course_key = problem_location.course_key
        problem_new_name = 'New Problem Name'

        def assertNumProblems(display_name, expected_number):
            """
            Asserts the number of problems with the given display name is the given expected number.
            """
            self.assertEquals(
                len(self.store.get_items(course_key.for_branch(None), settings={'display_name': display_name})),
                expected_number
            )

        def assertProblemNameEquals(expected_display_name):
            """
            Asserts the display_name of the xblock at problem_location matches the given expected value.
            """
            # check the display_name of the problem
            problem = self.store.get_item(problem_location)
            self.assertEquals(problem.display_name, expected_display_name)

            # there should be only 1 problem with the expected_display_name
            assertNumProblems(expected_display_name, 1)

        # verify Draft problem
        with self.store.branch_setting(ModuleStoreEnum.Branch.draft_preferred, course_key):
            self.assertTrue(self.store.has_item(problem_location))
            assertProblemNameEquals(problem_original_name)

        # verify Published problem doesn't exist
        with self.store.branch_setting(ModuleStoreEnum.Branch.published_only, course_key):
            self.assertFalse(self.store.has_item(problem_location))
            with self.assertRaises(ItemNotFoundError):
                self.store.get_item(problem_location)

        # PUBLISH the problem
        self.store.publish(self.vertical_x1a, self.user_id)
        self.store.publish(problem_location, self.user_id)

        # verify Published problem
        with self.store.branch_setting(ModuleStoreEnum.Branch.published_only, course_key):
            self.assertTrue(self.store.has_item(problem_location))
            assertProblemNameEquals(problem_original_name)

        # verify Draft-preferred
        with self.store.branch_setting(ModuleStoreEnum.Branch.draft_preferred, course_key):
            assertProblemNameEquals(problem_original_name)

        # EDIT name
        problem = self.store.get_item(problem_location)
        problem.display_name = problem_new_name
        self.store.update_item(problem, self.user_id)

        # verify Draft problem has new name
        with self.store.branch_setting(ModuleStoreEnum.Branch.draft_preferred, course_key):
            assertProblemNameEquals(problem_new_name)

        # verify Published problem still has old name
        with self.store.branch_setting(ModuleStoreEnum.Branch.published_only, course_key):
            assertProblemNameEquals(problem_original_name)
            # there should be no published problems with the new name
            assertNumProblems(problem_new_name, 0)

        # PUBLISH the problem
        self.store.publish(problem_location, self.user_id)

        # verify Published problem has new name
        with self.store.branch_setting(ModuleStoreEnum.Branch.published_only, course_key):
            assertProblemNameEquals(problem_new_name)
            # there should be no published problems with the old name
            assertNumProblems(problem_original_name, 0)

    def verify_default_store(self, store_type):
        """
        Verifies the default_store property
        """
        self.assertEquals(self.store.default_modulestore.get_modulestore_type(), store_type)

        # verify internal helper method
        store = self.store._get_modulestore_for_courseid()  # pylint: disable=protected-access
        self.assertEquals(store.get_modulestore_type(), store_type)

        # verify store used for creating a course
        try:
            course = self.store.create_course("org", "course{}".format(uuid4().hex[:5]), "run", self.user_id)
            self.assertEquals(course.system.modulestore.get_modulestore_type(), store_type)
        except NotImplementedError:
            self.assertEquals(store_type, ModuleStoreEnum.Type.xml)

    @ddt.data(ModuleStoreEnum.Type.mongo, ModuleStoreEnum.Type.split, ModuleStoreEnum.Type.xml)
    def test_default_store(self, default_ms):
        """
        Test the default store context manager
        """
        # initialize the mixed modulestore
        self._initialize_mixed(mappings={})

        with self.store.default_store(default_ms):
            self.verify_default_store(default_ms)

    def test_default_store_nested(self):
        """
        Test the default store context manager, nested within one another
        """
        # initialize the mixed modulestore
        self._initialize_mixed(mappings={})

        with self.store.default_store(ModuleStoreEnum.Type.mongo):
            self.verify_default_store(ModuleStoreEnum.Type.mongo)
            with self.store.default_store(ModuleStoreEnum.Type.split):
                self.verify_default_store(ModuleStoreEnum.Type.split)
                with self.store.default_store(ModuleStoreEnum.Type.xml):
                    self.verify_default_store(ModuleStoreEnum.Type.xml)
                self.verify_default_store(ModuleStoreEnum.Type.split)
            self.verify_default_store(ModuleStoreEnum.Type.mongo)

    def test_default_store_fake(self):
        """
        Test the default store context manager, asking for a fake store
        """
        # initialize the mixed modulestore
        self._initialize_mixed(mappings={})

        fake_store = "fake"
        with self.assertRaisesRegexp(Exception, "Cannot find store of type {}".format(fake_store)):
            with self.store.default_store(fake_store):
                pass  # pragma: no cover

    def save_asset(self, asset_key):
        """
        Load and save the given file. (taken from test_contentstore)
        """
        with open("{}/static/{}".format(DATA_DIR, asset_key.block_id), "rb") as f:
            content = StaticContent(
                asset_key, "Funky Pix", mimetypes.guess_type(asset_key.block_id)[0], f.read(),
            )
            self.store.contentstore.save(content)

    @ddt.data(
        [ModuleStoreEnum.Type.mongo, ModuleStoreEnum.Type.mongo],
        [ModuleStoreEnum.Type.mongo, ModuleStoreEnum.Type.split],
        [ModuleStoreEnum.Type.split, ModuleStoreEnum.Type.split]
    )
    @ddt.unpack
    def test_clone_course(self, source_modulestore, destination_modulestore):
        """
        Test clone course
        """

        with MongoContentstoreBuilder().build() as contentstore:
            # initialize the mixed modulestore
            self._initialize_mixed(contentstore=contentstore, mappings={})

            with self.store.default_store(source_modulestore):

                source_course_key = self.store.make_course_key("org.source", "course.source", "run.source")
                self._create_course(source_course_key)
                self.save_asset(source_course_key.make_asset_key('asset', 'picture1.jpg'))

            with self.store.default_store(destination_modulestore):
                dest_course_id = self.store.make_course_key("org.other", "course.other", "run.other")
                self.store.clone_course(source_course_key, dest_course_id, self.user_id)

                # pylint: disable=protected-access
            source_store = self.store._get_modulestore_by_type(source_modulestore)
            dest_store = self.store._get_modulestore_by_type(destination_modulestore)
            self.assertCoursesEqual(source_store, source_course_key, dest_store, dest_course_id)

    def test_clone_xml_split(self):
        """
        Can clone xml courses to split; so, test it.
        """
        with MongoContentstoreBuilder().build() as contentstore:
            # initialize the mixed modulestore
            self._initialize_mixed(contentstore=contentstore, mappings={self.XML_COURSEID2: 'xml', })
            source_course_key = CourseKey.from_string(self.XML_COURSEID2)
            with self.store.default_store(ModuleStoreEnum.Type.split):
                dest_course_id = CourseLocator("org.other", "course.other", "run.other")
                self.store.clone_course(
                    source_course_key, dest_course_id, ModuleStoreEnum.UserID.test
                )

            # pylint: disable=protected-access
            source_store = self.store._get_modulestore_by_type(ModuleStoreEnum.Type.xml)
            dest_store = self.store._get_modulestore_by_type(ModuleStoreEnum.Type.split)
            self.assertCoursesEqual(source_store, source_course_key, dest_store, dest_course_id)

    @ddt.data(ModuleStoreEnum.Type.mongo, ModuleStoreEnum.Type.split)
    def test_import_delete_import(self, default):
        """
        Test that deleting an element after import and then re-importing restores that element in draft
        as well as published branches (PLAT_297)
        """
        # set the default modulestore
        with MongoContentstoreBuilder().build() as contentstore:
            self.store = MixedModuleStore(
                contentstore=contentstore,
                create_modulestore_instance=create_modulestore_instance,
                mappings={},
                **self.OPTIONS
            )
            self.addCleanup(self.store.close_all_connections)
            with self.store.default_store(default):
                dest_course_key = self.store.make_course_key('a', 'course', 'course')
                courses = import_from_xml(
                    self.store, self.user_id, DATA_DIR, ['toy'], load_error_modules=False,
                    static_content_store=contentstore,
                    target_course_id=dest_course_key,
                    create_new_course_if_not_present=True,
                )
                course_id = courses[0].id
                # no need to verify course content here as test_cross_modulestore_import_export does that
                # delete the vertical
                vertical_loc = course_id.make_usage_key('vertical', 'vertical_test')
                self.assertTrue(self.store.has_item(vertical_loc))
                with self.store.branch_setting(ModuleStoreEnum.Branch.draft_preferred, course_id):
                    self.store.delete_item(vertical_loc, self.user_id)
                # verify it's in the published still
                with self.store.branch_setting(ModuleStoreEnum.Branch.published_only, course_id):
                    self.assertTrue(self.store.has_item(vertical_loc))

                # now re-import
                import_from_xml(
                    self.store, self.user_id, DATA_DIR, ['toy'], load_error_modules=False,
                    static_content_store=contentstore,
                    target_course_id=dest_course_key,
                )
                # verify it's in both published and draft
                with self.store.branch_setting(ModuleStoreEnum.Branch.draft_preferred, course_id):
                    self.assertTrue(self.store.has_item(vertical_loc))
                with self.store.branch_setting(ModuleStoreEnum.Branch.published_only, course_id):
                    self.assertTrue(self.store.has_item(vertical_loc))

    @ddt.data(ModuleStoreEnum.Type.mongo, ModuleStoreEnum.Type.split)
    def test_import_edit_import(self, default):
        """
        Test that editing an element after import and then re-importing resets the draft and pub'd
        to the imported pub'd value (PLAT-299)
        """
        if default == ModuleStoreEnum.Type.mongo:
            raise SkipTest
        # set the default modulestore
        with MongoContentstoreBuilder().build() as contentstore:
            self.store = MixedModuleStore(
                contentstore=contentstore,
                create_modulestore_instance=create_modulestore_instance,
                mappings={},
                **self.OPTIONS
            )
            self.addCleanup(self.store.close_all_connections)
            with self.store.default_store(default):
                dest_course_key = self.store.make_course_key('a', 'course', 'course')
                courses = import_from_xml(
                    self.store, self.user_id, DATA_DIR, ['toy'], load_error_modules=False,
                    static_content_store=contentstore,
                    target_course_id=dest_course_key,
                    create_new_course_if_not_present=True,
                )
                course_id = courses[0].id
                # no need to verify course content here as test_cross_modulestore_import_export does that
                # delete the vertical
                vertical_loc = course_id.make_usage_key('vertical', 'vertical_test')
                with self.store.branch_setting(ModuleStoreEnum.Branch.draft_preferred, course_id):
                    vertical = self.store.get_item(vertical_loc)
                    vertical.display_name = "4"
                    self.store.update_item(vertical, self.user_id)

                # now re-import
                import_from_xml(
                    self.store, self.user_id, DATA_DIR, ['toy'], load_error_modules=False,
                    static_content_store=contentstore,
                    target_course_id=dest_course_key,
                )
                # verify it's the same in both published and draft (toy has no drafts)
                with self.store.branch_setting(ModuleStoreEnum.Branch.draft_preferred, course_id):
                    draft_vertical = self.store.get_item(vertical_loc)
                with self.store.branch_setting(ModuleStoreEnum.Branch.published_only, course_id):
                    published_vertical = self.store.get_item(vertical_loc)
                self.assertEqual(draft_vertical.display_name, published_vertical.display_name)

# ============================================================================================================
# General utils for not using django settings
# ============================================================================================================


def load_function(path):
    """
    Load a function by name.

    path is a string of the form "path.to.module.function"
    returns the imported python object `function` from `path.to.module`
    """
    module_path, _, name = path.rpartition('.')
    return getattr(import_module(module_path), name)


# pylint: disable=unused-argument
def create_modulestore_instance(engine, contentstore, doc_store_config, options, i18n_service=None, fs_service=None):
    """
    This will return a new instance of a modulestore given an engine and options
    """
    class_ = load_function(engine)

    if issubclass(class_, ModuleStoreDraftAndPublished):
        options['branch_setting_func'] = lambda: ModuleStoreEnum.Branch.draft_preferred

    return class_(
        doc_store_config=doc_store_config,
        contentstore=contentstore,
        **options
    )
