# Copyright 2016 The Chromium Authors. All rights reserved.
# Use of this source code is governed by a BSD-style
# license that can be found in the LICENSE file or at
# https://developers.google.com/open-source/licenses/bsd

"""Tests for the frontendsearchpipeline module."""
from __future__ import print_function
from __future__ import division
from __future__ import absolute_import

import mox
import unittest

from google.appengine.api import memcache
from google.appengine.api import modules
from google.appengine.ext import testbed
from google.appengine.api import urlfetch

import settings
from framework import framework_helpers
from framework import sorting
from framework import urls
from proto import ast_pb2
from proto import project_pb2
from proto import tracker_pb2
from search import frontendsearchpipeline
from search import searchpipeline
from search import query2ast
from services import service_manager
from testing import fake
from testing import testing_helpers
from tracker import tracker_bizobj


# Just an example timestamp.  The value does not matter.
NOW = 2444950132


class FrontendSearchPipelineTest(unittest.TestCase):

  def setUp(self):
    self.config = tracker_bizobj.MakeDefaultProjectIssueConfig(789)
    self.services = service_manager.Services(
        user=fake.UserService(),
        project=fake.ProjectService(),
        issue=fake.IssueService(),
        config=fake.ConfigService(),
        cache_manager=fake.CacheManager())
    self.services.user.TestAddUser('a@example.com', 111)
    self.project = self.services.project.TestAddProject('proj', project_id=789)
    self.mr = testing_helpers.MakeMonorailRequest(
      path='/p/proj/issues/list', project=self.project)
    self.mr.me_user_id = 111

    self.issue_1 = fake.MakeTestIssue(
      789, 1, 'one', 'New', 111, labels=['Priority-High'])
    self.services.issue.TestAddIssue(self.issue_1)
    self.issue_2 = fake.MakeTestIssue(
      789, 2, 'two', 'New', 111, labels=['Priority-Low'])
    self.services.issue.TestAddIssue(self.issue_2)
    self.issue_3 = fake.MakeTestIssue(
      789, 3, 'three', 'New', 111, labels=['Priority-Medium'])
    self.services.issue.TestAddIssue(self.issue_3)
    self.mr.sort_spec = 'Priority'

    self.cnxn = self.mr.cnxn
    self.project = self.mr.project
    self.auth = self.mr.auth
    self.me_user_id = self.mr.me_user_id
    self.query = self.mr.query
    self.query_project_names = self.mr.query_project_names
    self.items_per_page = self.mr.num # defaults to 100
    self.paginate_start = self.mr.start
    self.paginate_end = self.paginate_start + self.items_per_page
    self.can = self.mr.can
    self.group_by_spec = self.mr.group_by_spec
    self.sort_spec = self.mr.sort_spec
    self.warnings = self.mr.warnings
    self.errors = self.mr.errors
    self.use_cached_searches = self.mr.use_cached_searches
    self.profiler = self.mr.profiler

    self.mox = mox.Mox()
    self.testbed = testbed.Testbed()
    self.testbed.activate()
    self.testbed.init_user_stub()
    self.testbed.init_memcache_stub()
    sorting.InitializeArtValues(self.services)

  def tearDown(self):
    self.testbed.deactivate()
    self.mox.UnsetStubs()
    self.mox.ResetAll()

  def testSearchForIIDs_AllResultsCached_AllAtRiskCached(self):
    unfiltered_iids = {(1, 'p:v'): [1001, 1011]}
    nonviewable_iids = {1: set()}
    self.mox.StubOutWithMock(frontendsearchpipeline, '_StartBackendSearch')
    frontendsearchpipeline._StartBackendSearch(
        self.cnxn, ['proj'], [789], mox.IsA(tracker_pb2.ProjectIssueConfig),
        unfiltered_iids, {}, nonviewable_iids, set(), self.services,
        self.me_user_id, self.auth.user_id or 0, self.paginate_end,
        self.query.split(' OR '), self.can, self.group_by_spec, self.sort_spec,
        self.warnings, self.use_cached_searches).AndReturn([])
    self.mox.StubOutWithMock(frontendsearchpipeline, '_FinishBackendSearch')
    frontendsearchpipeline._FinishBackendSearch([])
    self.mox.ReplayAll()

    pipeline = frontendsearchpipeline.FrontendSearchPipeline(
        self.cnxn,
        self.services,
        self.auth,
        self.me_user_id,
        self.query,
        self.query_project_names,
        self.items_per_page,
        self.paginate_start,
        self.can,
        self.group_by_spec,
        self.sort_spec,
        self.warnings,
        self.errors,
        self.use_cached_searches,
        self.profiler,
        project=self.project)
    pipeline.unfiltered_iids = unfiltered_iids
    pipeline.nonviewable_iids = nonviewable_iids
    pipeline.SearchForIIDs()
    self.mox.VerifyAll()
    self.assertEqual(2, pipeline.total_count)
    self.assertEqual([1001, 1011], pipeline.filtered_iids[(1, 'p:v')])

  def testSearchForIIDs_CrossProject_AllViewable(self):
    self.services.project.TestAddProject('other', project_id=790)
    unfiltered_iids = {(1, 'p:v'): [1001, 1011, 2001]}
    nonviewable_iids = {1: set()}
    self.query_project_names = ['other']
    self.mox.StubOutWithMock(frontendsearchpipeline, '_StartBackendSearch')
    frontendsearchpipeline._StartBackendSearch(
        self.cnxn, ['other', 'proj'], [789, 790],
        mox.IsA(tracker_pb2.ProjectIssueConfig), unfiltered_iids, {},
        nonviewable_iids, set(), self.services,
        self.me_user_id, self.auth.user_id or 0, self.paginate_end,
        self.query.split(' OR '), self.can, self.group_by_spec, self.sort_spec,
        self.warnings, self.use_cached_searches).AndReturn([])
    self.mox.StubOutWithMock(frontendsearchpipeline, '_FinishBackendSearch')
    frontendsearchpipeline._FinishBackendSearch([])
    self.mox.ReplayAll()

    pipeline = frontendsearchpipeline.FrontendSearchPipeline(
        self.cnxn,
        self.services,
        self.auth,
        self.me_user_id,
        self.query,
        self.query_project_names,
        self.items_per_page,
        self.paginate_start,
        self.can,
        self.group_by_spec,
        self.sort_spec,
        self.warnings,
        self.errors,
        self.use_cached_searches,
        self.profiler,
        project=self.project)

    pipeline.unfiltered_iids = unfiltered_iids
    pipeline.nonviewable_iids = nonviewable_iids
    pipeline.SearchForIIDs()
    self.mox.VerifyAll()
    self.assertEqual(3, pipeline.total_count)
    self.assertEqual([1001, 1011, 2001], pipeline.filtered_iids[(1, 'p:v')])

  def testSearchForIIDs_CrossProject_MembersOnlyOmitted(self):
    self.services.project.TestAddProject(
        'other', project_id=790, access=project_pb2.ProjectAccess.MEMBERS_ONLY)
    unfiltered_iids = {(1, 'p:v'): [1001, 1011]}
    nonviewable_iids = {1: set()}
    # project 'other' gets filtered out before the backend call.
    self.mr.query_project_names = ['other']
    self.mox.StubOutWithMock(frontendsearchpipeline, '_StartBackendSearch')
    frontendsearchpipeline._StartBackendSearch(
        self.cnxn, ['proj'], [789], mox.IsA(tracker_pb2.ProjectIssueConfig),
        unfiltered_iids, {}, nonviewable_iids, set(), self.services,
        self.me_user_id, self.auth.user_id or 0, self.paginate_end,
        self.query.split(' OR '), self.can, self.group_by_spec, self.sort_spec,
        self.warnings, self.use_cached_searches).AndReturn([])
    self.mox.StubOutWithMock(frontendsearchpipeline, '_FinishBackendSearch')
    frontendsearchpipeline._FinishBackendSearch([])
    self.mox.ReplayAll()

    pipeline = frontendsearchpipeline.FrontendSearchPipeline(
        self.cnxn,
        self.services,
        self.auth,
        self.me_user_id,
        self.query,
        self.query_project_names,
        self.items_per_page,
        self.paginate_start,
        self.can,
        self.group_by_spec,
        self.sort_spec,
        self.warnings,
        self.errors,
        self.use_cached_searches,
        self.profiler,
        project=self.project)
    pipeline.unfiltered_iids = unfiltered_iids
    pipeline.nonviewable_iids = nonviewable_iids
    pipeline.SearchForIIDs()
    self.mox.VerifyAll()
    self.assertEqual(2, pipeline.total_count)
    self.assertEqual([1001, 1011], pipeline.filtered_iids[(1, 'p:v')])

  def testMergeAndSortIssues_EmptyResult(self):
    pipeline = frontendsearchpipeline.FrontendSearchPipeline(
        self.cnxn,
        self.services,
        self.auth,
        self.me_user_id,
        self.query,
        self.query_project_names,
        self.items_per_page,
        self.paginate_start,
        self.can,
        self.group_by_spec,
        self.sort_spec,
        self.warnings,
        self.errors,
        self.use_cached_searches,
        self.profiler,
        project=self.project)
    pipeline.filtered_iids = {0: [], 1: [], 2: []}

    pipeline.MergeAndSortIssues()
    self.assertEqual([], pipeline.allowed_iids)
    self.assertEqual([], pipeline.allowed_results)
    self.assertEqual({}, pipeline.users_by_id)

  def testMergeAndSortIssues_Normal(self):
    pipeline = frontendsearchpipeline.FrontendSearchPipeline(
        self.cnxn,
        self.services,
        self.auth,
        self.me_user_id,
        self.query,
        self.query_project_names,
        self.items_per_page,
        self.paginate_start,
        self.can,
        self.group_by_spec,
        self.sort_spec,
        self.warnings,
        self.errors,
        self.use_cached_searches,
        self.profiler,
        project=self.project)
    # In this unit test case we are not calling SearchForIIDs(), instead just
    # set pipeline.filtered_iids directly.
    pipeline.filtered_iids = {
      0: [],
      1: [self.issue_1.issue_id],
      2: [self.issue_2.issue_id],
      3: [self.issue_3.issue_id]
      }

    pipeline.MergeAndSortIssues()
    self.assertEqual(
      [self.issue_1.issue_id, self.issue_2.issue_id, self.issue_3.issue_id],
      pipeline.allowed_iids)
    self.assertEqual(
      [self.issue_1, self.issue_3, self.issue_2],  # high, medium, low.
      pipeline.allowed_results)
    self.assertEqual([0, 111], list(pipeline.users_by_id.keys()))

  def testDetermineIssuePosition_Normal(self):
    pipeline = frontendsearchpipeline.FrontendSearchPipeline(
        self.cnxn,
        self.services,
        self.auth,
        self.me_user_id,
        self.query,
        self.query_project_names,
        self.items_per_page,
        self.paginate_start,
        self.can,
        self.group_by_spec,
        self.sort_spec,
        self.warnings,
        self.errors,
        self.use_cached_searches,
        self.profiler,
        project=self.project)
    # In this unit test case we are not calling SearchForIIDs(), instead just
    # set pipeline.filtered_iids directly.
    pipeline.filtered_iids = {
      0: [],
      1: [self.issue_1.issue_id],
      2: [self.issue_2.issue_id],
      3: [self.issue_3.issue_id]
      }

    prev_iid, index, next_iid = pipeline.DetermineIssuePosition(self.issue_3)
    # The total ordering is issue_1, issue_3, issue_2 for high, med, low.
    self.assertEqual(self.issue_1.issue_id, prev_iid)
    self.assertEqual(1, index)
    self.assertEqual(self.issue_2.issue_id, next_iid)

  def testDetermineIssuePosition_NotInResults(self):
    pipeline = frontendsearchpipeline.FrontendSearchPipeline(
        self.cnxn,
        self.services,
        self.auth,
        self.me_user_id,
        self.query,
        self.query_project_names,
        self.items_per_page,
        self.paginate_start,
        self.can,
        self.group_by_spec,
        self.sort_spec,
        self.warnings,
        self.errors,
        self.use_cached_searches,
        self.profiler,
        project=self.project)
    # In this unit test case we are not calling SearchForIIDs(), instead just
    # set pipeline.filtered_iids directly.
    pipeline.filtered_iids = {
      0: [],
      1: [self.issue_1.issue_id],
      2: [self.issue_2.issue_id],
      3: []
      }

    prev_iid, index, next_iid = pipeline.DetermineIssuePosition(self.issue_3)
    # The total ordering is issue_1, issue_3, issue_2 for high, med, low.
    self.assertEqual(None, prev_iid)
    self.assertEqual(None, index)
    self.assertEqual(None, next_iid)

  def testDetermineIssuePositionInShard_IssueIsInShard(self):
    pipeline = frontendsearchpipeline.FrontendSearchPipeline(
        self.cnxn,
        self.services,
        self.auth,
        self.me_user_id,
        self.query,
        self.query_project_names,
        self.items_per_page,
        self.paginate_start,
        self.can,
        self.group_by_spec,
        self.sort_spec,
        self.warnings,
        self.errors,
        self.use_cached_searches,
        self.profiler,
        project=self.project)
    # Let's assume issues 1, 2, and 3 are all in the same shard.
    pipeline.filtered_iids = {
      0: [self.issue_1.issue_id, self.issue_2.issue_id, self.issue_3.issue_id],
      }

    # The total ordering is issue_1, issue_3, issue_2 for high, med, low.
    prev_cand, index, next_cand = pipeline._DetermineIssuePositionInShard(
      0, self.issue_1, {})
    self.assertEqual(None, prev_cand)
    self.assertEqual(0, index)
    self.assertEqual(self.issue_3, next_cand)

    prev_cand, index, next_cand = pipeline._DetermineIssuePositionInShard(
      0, self.issue_3, {})
    self.assertEqual(self.issue_1, prev_cand)
    self.assertEqual(1, index)
    self.assertEqual(self.issue_2, next_cand)

    prev_cand, index, next_cand = pipeline._DetermineIssuePositionInShard(
      0, self.issue_2, {})
    self.assertEqual(self.issue_3, prev_cand)
    self.assertEqual(2, index)
    self.assertEqual(None, next_cand)

  def testDetermineIssuePositionInShard_IssueIsNotInShard(self):
    pipeline = frontendsearchpipeline.FrontendSearchPipeline(
        self.cnxn,
        self.services,
        self.auth,
        self.me_user_id,
        self.query,
        self.query_project_names,
        self.items_per_page,
        self.paginate_start,
        self.can,
        self.group_by_spec,
        self.sort_spec,
        self.warnings,
        self.errors,
        self.use_cached_searches,
        self.profiler,
        project=self.project)

    # The total ordering is issue_1, issue_3, issue_2 for high, med, low.
    pipeline.filtered_iids = {
      0: [self.issue_2.issue_id, self.issue_3.issue_id],
      }
    prev_cand, index, next_cand = pipeline._DetermineIssuePositionInShard(
      0, self.issue_1, {})
    self.assertEqual(None, prev_cand)
    self.assertEqual(0, index)
    self.assertEqual(self.issue_3, next_cand)

    pipeline.filtered_iids = {
      0: [self.issue_1.issue_id, self.issue_2.issue_id],
      }
    prev_cand, index, next_cand = pipeline._DetermineIssuePositionInShard(
      0, self.issue_3, {})
    self.assertEqual(self.issue_1, prev_cand)
    self.assertEqual(1, index)
    self.assertEqual(self.issue_2, next_cand)

    pipeline.filtered_iids = {
      0: [self.issue_1.issue_id, self.issue_3.issue_id],
      }
    prev_cand, index, next_cand = pipeline._DetermineIssuePositionInShard(
      0, self.issue_2, {})
    self.assertEqual(self.issue_3, prev_cand)
    self.assertEqual(2, index)
    self.assertEqual(None, next_cand)

  def testFetchAllSamples_Empty(self):
    filtered_iids = {}
    pipeline = frontendsearchpipeline.FrontendSearchPipeline(
        self.cnxn,
        self.services,
        self.auth,
        self.me_user_id,
        self.query,
        self.query_project_names,
        self.items_per_page,
        self.paginate_start,
        self.can,
        self.group_by_spec,
        self.sort_spec,
        self.warnings,
        self.errors,
        self.use_cached_searches,
        self.profiler,
        project=self.project)
    samples_by_shard, sample_iids_to_shard = pipeline._FetchAllSamples(
        filtered_iids)
    self.assertEqual({}, samples_by_shard)
    self.assertEqual({}, sample_iids_to_shard)

  def testFetchAllSamples_SmallResultsPerShard(self):
    filtered_iids = {
        0: [100, 110, 120],
        1: [101, 111, 121],
        }
    pipeline = frontendsearchpipeline.FrontendSearchPipeline(
        self.cnxn,
        self.services,
        self.auth,
        self.me_user_id,
        self.query,
        self.query_project_names,
        self.items_per_page,
        self.paginate_start,
        self.can,
        self.group_by_spec,
        self.sort_spec,
        self.warnings,
        self.errors,
        self.use_cached_searches,
        self.profiler,
        project=self.project)

    samples_by_shard, sample_iids_to_shard = pipeline._FetchAllSamples(
        filtered_iids)
    self.assertEqual(2, len(samples_by_shard))
    self.assertEqual(0, len(sample_iids_to_shard))

  def testFetchAllSamples_Normal(self):
    pipeline = frontendsearchpipeline.FrontendSearchPipeline(
        self.cnxn,
        self.services,
        self.auth,
        self.me_user_id,
        self.query,
        self.query_project_names,
        self.items_per_page,
        self.paginate_start,
        self.can,
        self.group_by_spec,
        self.sort_spec,
        self.warnings,
        self.errors,
        self.use_cached_searches,
        self.profiler,
        project=self.project)
    issues = self.MakeIssues(23)
    filtered_iids = {
        0: [issue.issue_id for issue in issues],
        }

    samples_by_shard, sample_iids_to_shard = pipeline._FetchAllSamples(
        filtered_iids)
    self.assertEqual(1, len(samples_by_shard))
    self.assertEqual(2, len(samples_by_shard[0]))
    self.assertEqual(2, len(sample_iids_to_shard))
    for sample_iid in sample_iids_to_shard:
      shard_key = sample_iids_to_shard[sample_iid]
      self.assertIn(sample_iid, filtered_iids[shard_key])

  def testChooseSampleIssues_Empty(self):
    """When the search gave no results, there cannot be any samples."""
    pipeline = frontendsearchpipeline.FrontendSearchPipeline(
        self.cnxn,
        self.services,
        self.auth,
        self.me_user_id,
        self.query,
        self.query_project_names,
        self.items_per_page,
        self.paginate_start,
        self.can,
        self.group_by_spec,
        self.sort_spec,
        self.warnings,
        self.errors,
        self.use_cached_searches,
        self.profiler,
        project=self.project)
    issue_ids = []
    on_hand_issues, needed_iids = pipeline._ChooseSampleIssues(issue_ids)
    self.assertEqual({}, on_hand_issues)
    self.assertEqual([], needed_iids)

  def testChooseSampleIssues_Small(self):
    """When the search gave few results, don't bother with samples."""
    pipeline = frontendsearchpipeline.FrontendSearchPipeline(
        self.cnxn,
        self.services,
        self.auth,
        self.me_user_id,
        self.query,
        self.query_project_names,
        self.items_per_page,
        self.paginate_start,
        self.can,
        self.group_by_spec,
        self.sort_spec,
        self.warnings,
        self.errors,
        self.use_cached_searches,
        self.profiler,
        project=self.project)
    issue_ids = [78901, 78902]
    on_hand_issues, needed_iids = pipeline._ChooseSampleIssues(issue_ids)
    self.assertEqual({}, on_hand_issues)
    self.assertEqual([], needed_iids)

  def MakeIssues(self, num_issues):
    issues = []
    for i in range(num_issues):
      issue = fake.MakeTestIssue(789, 100 + i, 'samp test', 'New', 111)
      issues.append(issue)
      self.services.issue.TestAddIssue(issue)
    return issues

  def testChooseSampleIssues_Normal(self):
    """We will choose at least one sample for every 10 results in a shard."""
    pipeline = frontendsearchpipeline.FrontendSearchPipeline(
        self.cnxn,
        self.services,
        self.auth,
        self.me_user_id,
        self.query,
        self.query_project_names,
        self.items_per_page,
        self.paginate_start,
        self.can,
        self.group_by_spec,
        self.sort_spec,
        self.warnings,
        self.errors,
        self.use_cached_searches,
        self.profiler,
        project=self.project)
    issues = self.MakeIssues(23)
    issue_ids = [issue.issue_id for issue in issues]
    on_hand_issues, needed_iids = pipeline._ChooseSampleIssues(issue_ids)
    self.assertEqual({}, on_hand_issues)
    self.assertEqual(2, len(needed_iids))
    for sample_iid in needed_iids:
      self.assertIn(sample_iid, issue_ids)

  def testLookupNeededUsers(self):
    pipeline = frontendsearchpipeline.FrontendSearchPipeline(
        self.cnxn,
        self.services,
        self.auth,
        self.me_user_id,
        self.query,
        self.query_project_names,
        self.items_per_page,
        self.paginate_start,
        self.can,
        self.group_by_spec,
        self.sort_spec,
        self.warnings,
        self.errors,
        self.use_cached_searches,
        self.profiler,
        project=self.project)

    pipeline._LookupNeededUsers([])
    self.assertEqual([], list(pipeline.users_by_id.keys()))

    pipeline._LookupNeededUsers([self.issue_1, self.issue_2, self.issue_3])
    self.assertEqual([0, 111], list(pipeline.users_by_id.keys()))

  def testPaginate_List(self):
    pipeline = frontendsearchpipeline.FrontendSearchPipeline(
        self.cnxn,
        self.services,
        self.auth,
        self.me_user_id,
        self.query,
        self.query_project_names,
        self.items_per_page,
        self.paginate_start,
        self.can,
        self.group_by_spec,
        self.sort_spec,
        self.warnings,
        self.errors,
        self.use_cached_searches,
        self.profiler,
        project=self.project)
    pipeline.allowed_iids = [
      self.issue_1.issue_id, self.issue_2.issue_id, self.issue_3.issue_id]
    pipeline.allowed_results = [self.issue_1, self.issue_2, self.issue_3]
    pipeline.total_count = len(pipeline.allowed_results)
    pipeline.Paginate()
    self.assertEqual(
      [self.issue_1, self.issue_2, self.issue_3],
      pipeline.visible_results)
    self.assertFalse(pipeline.pagination.limit_reached)


class FrontendSearchPipelineMethodsTest(unittest.TestCase):

  def setUp(self):
    self.mox = mox.Mox()
    self.testbed = testbed.Testbed()
    self.testbed.activate()
    self.testbed.init_user_stub()
    self.testbed.init_memcache_stub()

    self.project_id = 789
    self.default_config = tracker_bizobj.MakeDefaultProjectIssueConfig(
        self.project_id)
    self.services = service_manager.Services(
        project=fake.ProjectService())
    self.project = self.services.project.TestAddProject(
        'proj', project_id=self.project_id)

  def tearDown(self):
    self.testbed.deactivate()
    self.mox.UnsetStubs()
    self.mox.ResetAll()

  def testMakeBackendCallback(self):
    called_with = []

    def func(a, b):
      called_with.append((a, b))

    callback = frontendsearchpipeline._MakeBackendCallback(func, 10, 20)
    callback()
    self.assertEqual([(10, 20)], called_with)

  def testParseUserQuery_CheckQuery(self):
    warnings = []
    msg = frontendsearchpipeline._CheckQuery(
        'cnxn', self.services, 'ok query', self.default_config,
        [self.project_id], True, warnings=warnings)
    self.assertIsNone(msg)
    self.assertEqual([], warnings)

    warnings = []
    msg = frontendsearchpipeline._CheckQuery(
        'cnxn', self.services, 'modified:0-0-0', self.default_config,
        [self.project_id], True, warnings=warnings)
    self.assertEqual(
        'Could not parse date: 0-0-0',
        msg)

    warnings = []
    msg = frontendsearchpipeline._CheckQuery(
        'cnxn', self.services, 'blocking:3.14', self.default_config,
        [self.project_id], True, warnings=warnings)
    self.assertEqual(
        'Could not parse issue reference: 3.14',
        msg)
    self.assertEqual([], warnings)

  def testStartBackendSearch(self):
    # TODO(jrobbins): write this test.
    pass

  def testFinishBackendSearch(self):
    # TODO(jrobbins): write this test.
    pass

  def testGetProjectTimestamps_NoneSet(self):
    project_shard_timestamps = frontendsearchpipeline._GetProjectTimestamps(
      [], [])
    self.assertEqual({}, project_shard_timestamps)

    project_shard_timestamps = frontendsearchpipeline._GetProjectTimestamps(
      [], [(0, (0, 'p:v')), (1, (1, 'p:v')), (2, (2, 'p:v'))])
    self.assertEqual({}, project_shard_timestamps)

    project_shard_timestamps = frontendsearchpipeline._GetProjectTimestamps(
      [789], [(0, (0, 'p:v')), (1, (1, 'p:v')), (2, (2, 'p:v'))])
    self.assertEqual({}, project_shard_timestamps)

  def testGetProjectTimestamps_SpecificProjects(self):
    memcache.set('789;0', NOW)
    memcache.set('789;1', NOW - 1000)
    memcache.set('789;2', NOW - 3000)
    project_shard_timestamps = frontendsearchpipeline._GetProjectTimestamps(
      [789], [(0, (0, 'p:v')), (1, (1, 'p:v')), (2, (2, 'p:v'))])
    self.assertEqual(
      { (789, 0): NOW,
        (789, 1): NOW - 1000,
        (789, 2): NOW - 3000,
        },
      project_shard_timestamps)

    memcache.set('790;0', NOW)
    memcache.set('790;1', NOW - 10000)
    memcache.set('790;2', NOW - 30000)
    project_shard_timestamps = frontendsearchpipeline._GetProjectTimestamps(
      [789, 790], [(0, (0, 'p:v')), (1, (1, 'p:v')), (2, (2, 'p:v'))])
    self.assertEqual(
      { (789, 0): NOW,
        (789, 1): NOW - 1000,
        (789, 2): NOW - 3000,
        (790, 0): NOW,
        (790, 1): NOW - 10000,
        (790, 2): NOW - 30000,
        },
      project_shard_timestamps)

  def testGetProjectTimestamps_SiteWide(self):
    memcache.set('all;0', NOW)
    memcache.set('all;1', NOW - 10000)
    memcache.set('all;2', NOW - 30000)
    project_shard_timestamps = frontendsearchpipeline._GetProjectTimestamps(
      [], [(0, (0, 'p:v')), (1, (1, 'p:v')), (2, (2, 'p:v'))])
    self.assertEqual(
      { ('all', 0): NOW,
        ('all', 1): NOW - 10000,
        ('all', 2): NOW - 30000,
        },
      project_shard_timestamps)

  def testGetNonviewableIIDs_SearchMissSoNoOp(self):
    """If search cache missed, don't bother looking up nonviewable IIDs."""
    unfiltered_iids_dict = {}  # No cached search results found.
    rpc_tuples = []  # Nothing should accumulate here in this case.
    nonviewable_iids = {}  # Nothing should accumulate here in this case.
    processed_invalidations_up_to = 12345
    frontendsearchpipeline._GetNonviewableIIDs(
        [789], 111, list(unfiltered_iids_dict.keys()), rpc_tuples,
        nonviewable_iids, {}, processed_invalidations_up_to, True)
    self.assertEqual([], rpc_tuples)
    self.assertEqual({}, nonviewable_iids)

  def testGetNonviewableIIDs_SearchHitThenNonviewableHit(self):
    """If search cache hit, get nonviewable info from cache."""
    unfiltered_iids_dict = {
      1: [10001, 10021],
      2: ['the search result issue_ids do not matter'],
      }
    rpc_tuples = []  # Nothing should accumulate here in this case.
    nonviewable_iids = {}  # Our mock results should end up here.
    processed_invalidations_up_to = 12345
    memcache.set('nonviewable:789;111;1',
                 ([10001, 10031], processed_invalidations_up_to - 10))
    memcache.set('nonviewable:789;111;2',
                 ([10002, 10042], processed_invalidations_up_to - 30))

    project_shard_timestamps = {
      (789, 1): 0,  # not stale
      (789, 2): 0,  # not stale
      }
    frontendsearchpipeline._GetNonviewableIIDs(
        [789], 111, list(unfiltered_iids_dict.keys()), rpc_tuples,
        nonviewable_iids, project_shard_timestamps,
        processed_invalidations_up_to, True)
    self.assertEqual([], rpc_tuples)
    self.assertEqual({1: {10001, 10031}, 2: {10002, 10042}}, nonviewable_iids)

  def testGetNonviewableIIDs_SearchHitNonviewableMissSoStartRPC(self):
    """If search hit and n-v miss, create RPCs to get nonviewable info."""
    self.mox.StubOutWithMock(
        frontendsearchpipeline, '_StartBackendNonviewableCall')
    unfiltered_iids_dict = {
      2: ['the search result issue_ids do not matter'],
      }
    rpc_tuples = []  # One RPC object should accumulate here.
    nonviewable_iids = {}  # This will stay empty until RPCs complete.
    processed_invalidations_up_to = 12345
    # Nothing is set in memcache for this case.
    a_fake_rpc = testing_helpers.Blank(callback=None)
    frontendsearchpipeline._StartBackendNonviewableCall(
      789, 111, 2, processed_invalidations_up_to).AndReturn(a_fake_rpc)
    self.mox.ReplayAll()

    frontendsearchpipeline._GetNonviewableIIDs(
        [789], 111, list(unfiltered_iids_dict.keys()), rpc_tuples,
        nonviewable_iids, {}, processed_invalidations_up_to, True)
    self.mox.VerifyAll()
    _, sid_0, rpc_0 = rpc_tuples[0]
    self.assertEqual(2, sid_0)
    self.assertEqual({}, nonviewable_iids)
    self.assertEqual(a_fake_rpc, rpc_0)
    self.assertIsNotNone(a_fake_rpc.callback)

  def testAccumulateNonviewableIIDs_MemcacheHitForProject(self):
    processed_invalidations_up_to = 12345
    cached_dict = {
      '789;111;2': ([10002, 10042], processed_invalidations_up_to - 10),
      '789;111;3': ([10003, 10093], processed_invalidations_up_to - 30),
      }
    rpc_tuples = []  # Nothing should accumulate here.
    nonviewable_iids = {1: {10001}}  # This will gain the shard 2 values.
    project_shard_timestamps = {
      (789, 1): 0,  # not stale
      (789, 2): 0,  # not stale
      }
    frontendsearchpipeline._AccumulateNonviewableIIDs(
      789, 111, 2, cached_dict, nonviewable_iids, project_shard_timestamps,
      rpc_tuples, processed_invalidations_up_to)
    self.assertEqual([], rpc_tuples)
    self.assertEqual({1: {10001}, 2: {10002, 10042}}, nonviewable_iids)

  def testAccumulateNonviewableIIDs_MemcacheStaleForProject(self):
    self.mox.StubOutWithMock(
      frontendsearchpipeline, '_StartBackendNonviewableCall')
    processed_invalidations_up_to = 12345
    cached_dict = {
      '789;111;2': ([10002, 10042], processed_invalidations_up_to - 10),
      '789;111;3': ([10003, 10093], processed_invalidations_up_to - 30),
      }
    rpc_tuples = []  # Nothing should accumulate here.
    nonviewable_iids = {1: {10001}}  # Nothing added here until RPC completes
    project_shard_timestamps = {
      (789, 1): 0,  # not stale
      (789, 2): processed_invalidations_up_to,  # stale!
      }
    a_fake_rpc = testing_helpers.Blank(callback=None)
    frontendsearchpipeline._StartBackendNonviewableCall(
      789, 111, 2, processed_invalidations_up_to).AndReturn(a_fake_rpc)
    self.mox.ReplayAll()

    frontendsearchpipeline._AccumulateNonviewableIIDs(
      789, 111, 2, cached_dict, nonviewable_iids, project_shard_timestamps,
      rpc_tuples, processed_invalidations_up_to)
    self.mox.VerifyAll()
    _, sid_0, rpc_0 = rpc_tuples[0]
    self.assertEqual(2, sid_0)
    self.assertEqual(a_fake_rpc, rpc_0)
    self.assertIsNotNone(a_fake_rpc.callback)
    self.assertEqual({1: {10001}}, nonviewable_iids)

  def testAccumulateNonviewableIIDs_MemcacheHitForWholeSite(self):
    processed_invalidations_up_to = 12345
    cached_dict = {
      'all;111;2': ([10002, 10042], processed_invalidations_up_to - 10),
      'all;111;3': ([10003, 10093], processed_invalidations_up_to - 30),
      }
    rpc_tuples = []  # Nothing should accumulate here.
    nonviewable_iids = {1: {10001}}  # This will gain the shard 2 values.
    project_shard_timestamps = {
      (None, 1): 0,  # not stale
      (None, 2): 0,  # not stale
      }
    frontendsearchpipeline._AccumulateNonviewableIIDs(
      None, 111, 2, cached_dict, nonviewable_iids, project_shard_timestamps,
      rpc_tuples, processed_invalidations_up_to)
    self.assertEqual([], rpc_tuples)
    self.assertEqual({1: {10001}, 2: {10002, 10042}}, nonviewable_iids)

  def testAccumulateNonviewableIIDs_MemcacheMissSoStartRPC(self):
    self.mox.StubOutWithMock(
        frontendsearchpipeline, '_StartBackendNonviewableCall')
    cached_dict = {}  # Nothing here, so it is an at-risk cache miss.
    rpc_tuples = []  # One RPC should accumulate here.
    nonviewable_iids = {1: {10001}}  # Nothing added here until RPC completes.
    processed_invalidations_up_to = 12345
    a_fake_rpc = testing_helpers.Blank(callback=None)
    frontendsearchpipeline._StartBackendNonviewableCall(
      789, 111, 2, processed_invalidations_up_to).AndReturn(a_fake_rpc)
    self.mox.ReplayAll()

    frontendsearchpipeline._AccumulateNonviewableIIDs(
      789, 111, 2, cached_dict, nonviewable_iids, {}, rpc_tuples,
      processed_invalidations_up_to)
    self.mox.VerifyAll()
    _, sid_0, rpc_0 = rpc_tuples[0]
    self.assertEqual(2, sid_0)
    self.assertEqual(a_fake_rpc, rpc_0)
    self.assertIsNotNone(a_fake_rpc.callback)
    self.assertEqual({1: {10001}}, nonviewable_iids)

  def testGetCachedSearchResults(self):
    # TODO(jrobbins): Write this test.
    pass

  def testMakeBackendRequestHeaders(self):
    headers = frontendsearchpipeline._MakeBackendRequestHeaders(False)
    self.assertNotIn('X-AppEngine-FailFast', headers)
    headers = frontendsearchpipeline._MakeBackendRequestHeaders(True)
    self.assertEqual('Yes', headers['X-AppEngine-FailFast'])

  def testStartBackendSearchCall(self):
    self.mox.StubOutWithMock(urlfetch, 'create_rpc')
    self.mox.StubOutWithMock(urlfetch, 'make_fetch_call')
    self.mox.StubOutWithMock(modules, 'get_hostname')
    a_fake_rpc = testing_helpers.Blank(callback=None)
    urlfetch.create_rpc(deadline=settings.backend_deadline).AndReturn(
      a_fake_rpc)
    modules.get_hostname(module='default')
    urlfetch.make_fetch_call(
      a_fake_rpc, mox.StrContains(
          urls.BACKEND_SEARCH + '?groupby=cc&invalidation_timestep=12345&'
          +'logged_in_user_id=777&me_user_ids=555&'
          +'num=201&projects=proj&q=priority%3Dhigh&shard_id=2&start=0'),
          follow_redirects=False,
      headers=mox.IsA(dict))
    self.mox.ReplayAll()

    processed_invalidations_up_to = 12345
    me_user_ids = [555]
    logged_in_user_id = 777
    new_url_num = 201
    frontendsearchpipeline._StartBackendSearchCall(
        ['proj'], (2, 'priority=high'),
        processed_invalidations_up_to,
        me_user_ids,
        logged_in_user_id,
        new_url_num,
        group_by_spec='cc')
    self.mox.VerifyAll()

  def testStartBackendSearchCall_SortAndGroup(self):
    self.mox.StubOutWithMock(urlfetch, 'create_rpc')
    self.mox.StubOutWithMock(urlfetch, 'make_fetch_call')
    self.mox.StubOutWithMock(modules, 'get_hostname')
    a_fake_rpc = testing_helpers.Blank(callback=None)
    urlfetch.create_rpc(deadline=settings.backend_deadline).AndReturn(
      a_fake_rpc)
    modules.get_hostname(module='default')
    urlfetch.make_fetch_call(
        a_fake_rpc,
        mox.StrContains(
            urls.BACKEND_SEARCH + '?groupby=bar&' +
            'invalidation_timestep=12345&' +
            'logged_in_user_id=777&me_user_ids=555&num=201&projects=proj&' +
            'q=priority%3Dhigh&shard_id=2&sort=foo&start=0'),
        follow_redirects=False,
        headers=mox.IsA(dict))
    self.mox.ReplayAll()

    processed_invalidations_up_to = 12345
    me_user_ids = [555]
    logged_in_user_id = 777
    new_url_num = 201
    sort_spec = 'foo'
    group_by_spec = 'bar'
    frontendsearchpipeline._StartBackendSearchCall(
        ['proj'], (2, 'priority=high'),
        processed_invalidations_up_to,
        me_user_ids,
        logged_in_user_id,
        new_url_num,
        sort_spec=sort_spec,
        group_by_spec=group_by_spec)
    self.mox.VerifyAll()

  def testStartBackendNonviewableCall(self):
    self.mox.StubOutWithMock(urlfetch, 'create_rpc')
    self.mox.StubOutWithMock(urlfetch, 'make_fetch_call')
    self.mox.StubOutWithMock(modules, 'get_hostname')
    a_fake_rpc = testing_helpers.Blank(callback=None)
    urlfetch.create_rpc(deadline=settings.backend_deadline).AndReturn(
      a_fake_rpc)
    modules.get_hostname(module='default')
    urlfetch.make_fetch_call(
      a_fake_rpc, mox.StrContains(urls.BACKEND_NONVIEWABLE),
      follow_redirects=False, headers=mox.IsA(dict))
    self.mox.ReplayAll()

    processed_invalidations_up_to = 12345
    frontendsearchpipeline._StartBackendNonviewableCall(
      789, 111, 2, processed_invalidations_up_to)
    self.mox.VerifyAll()

  def testHandleBackendSearchResponse_500(self):
    response_str = 'There was a problem processing the query.'
    rpc = testing_helpers.Blank(
      get_result=lambda: testing_helpers.Blank(
          content=response_str, status_code=500))
    rpc_tuple = (NOW, 2, rpc)
    rpc_tuples = []  # Nothing should be added for this case.
    filtered_iids = {}  # Search results should accumlate here, per-shard.
    search_limit_reached = {}  # Booleans accumulate here, per-shard.
    processed_invalidations_up_to = 12345

    me_user_ids = [111]
    logged_in_user_id = 0
    new_url_num = 100
    error_responses = set()

    self.mox.StubOutWithMock(frontendsearchpipeline, '_StartBackendSearchCall')
    frontendsearchpipeline._HandleBackendSearchResponse(
        ['proj'], rpc_tuple, rpc_tuples, 0, filtered_iids, search_limit_reached,
        processed_invalidations_up_to, error_responses, me_user_ids,
        logged_in_user_id, new_url_num, 1, None, None)
    self.assertEqual([], rpc_tuples)
    self.assertIn(2, error_responses)

  def testHandleBackendSearchResponse_Error(self):
    response_str = (
      '})]\'\n'
      '{'
      ' "unfiltered_iids": [],'
      ' "search_limit_reached": false,'
      ' "error": "Invalid query"'
      '}'
      )
    rpc = testing_helpers.Blank(
      get_result=lambda: testing_helpers.Blank(
          content=response_str, status_code=200))
    rpc_tuple = (NOW, 2, rpc)
    rpc_tuples = []  # Nothing should be added for this case.
    filtered_iids = {}  # Search results should accumlate here, per-shard.
    search_limit_reached = {}  # Booleans accumulate here, per-shard.
    processed_invalidations_up_to = 12345

    me_user_ids = [111]
    logged_in_user_id = 0
    new_url_num = 100
    error_responses = set()
    frontendsearchpipeline._HandleBackendSearchResponse(
        ['proj'], rpc_tuple, rpc_tuples, 2, filtered_iids, search_limit_reached,
        processed_invalidations_up_to, error_responses, me_user_ids,
        logged_in_user_id, new_url_num, 1, None, None)
    self.assertEqual([], rpc_tuples)
    self.assertEqual({2: []}, filtered_iids)
    self.assertEqual({2: False}, search_limit_reached)
    self.assertEqual({2}, error_responses)

  def testHandleBackendSearchResponse_Normal(self):
    response_str = (
      '})]\'\n'
      '{'
      ' "unfiltered_iids": [10002, 10042],'
      ' "search_limit_reached": false'
      '}'
      )
    rpc = testing_helpers.Blank(
      get_result=lambda: testing_helpers.Blank(
          content=response_str, status_code=200))
    rpc_tuple = (NOW, 2, rpc)
    rpc_tuples = []  # Nothing should be added for this case.
    filtered_iids = {}  # Search results should accumlate here, per-shard.
    search_limit_reached = {}  # Booleans accumulate here, per-shard.
    processed_invalidations_up_to = 12345

    me_user_ids = [111]
    logged_in_user_id = 0
    new_url_num = 100
    error_responses = set()
    frontendsearchpipeline._HandleBackendSearchResponse(
        ['proj'], rpc_tuple, rpc_tuples, 2, filtered_iids, search_limit_reached,
        processed_invalidations_up_to, error_responses, me_user_ids,
        logged_in_user_id, new_url_num, 1, None, None)
    self.assertEqual([], rpc_tuples)
    self.assertEqual({2: [10002, 10042]}, filtered_iids)
    self.assertEqual({2: False}, search_limit_reached)

  def testHandleBackendSearchResponse_TriggersRetry(self):
    response_str = None
    rpc = testing_helpers.Blank(
      get_result=lambda: testing_helpers.Blank(content=response_str))
    rpc_tuple = (NOW, 2, rpc)
    rpc_tuples = []  # New RPC should be appended here
    filtered_iids = {}  # No change here until retry completes.
    search_limit_reached = {}  # No change here until retry completes.
    processed_invalidations_up_to = 12345
    error_responses = set()

    me_user_ids = [111]
    logged_in_user_id = 0
    new_url_num = 100

    self.mox.StubOutWithMock(frontendsearchpipeline, '_StartBackendSearchCall')
    a_fake_rpc = testing_helpers.Blank(callback=None)
    rpc = frontendsearchpipeline._StartBackendSearchCall(
        ['proj'],
        2,
        processed_invalidations_up_to,
        me_user_ids,
        logged_in_user_id,
        new_url_num,
        can=1,
        group_by_spec=None,
        sort_spec=None,
        failfast=False).AndReturn(a_fake_rpc)
    self.mox.ReplayAll()

    frontendsearchpipeline._HandleBackendSearchResponse(
        ['proj'], rpc_tuple, rpc_tuples, 2, filtered_iids, search_limit_reached,
        processed_invalidations_up_to, error_responses, me_user_ids,
        logged_in_user_id, new_url_num, 1, None, None)
    self.mox.VerifyAll()
    _, retry_shard_id, retry_rpc = rpc_tuples[0]
    self.assertEqual(2, retry_shard_id)
    self.assertEqual(a_fake_rpc, retry_rpc)
    self.assertIsNotNone(retry_rpc.callback)
    self.assertEqual({}, filtered_iids)
    self.assertEqual({}, search_limit_reached)

  def testHandleBackendNonviewableResponse_Error(self):
    response_str = 'There was an error.'
    rpc = testing_helpers.Blank(
      get_result=lambda: testing_helpers.Blank(
          content=response_str,
          status_code=500
      ))
    rpc_tuple = (NOW, 2, rpc)
    rpc_tuples = []  # Nothing should be added for this case.
    nonviewable_iids = {}  # At-risk issue IDs should accumlate here, per-shard.
    processed_invalidations_up_to = 12345

    self.mox.StubOutWithMock(
        frontendsearchpipeline, '_StartBackendNonviewableCall')
    frontendsearchpipeline._HandleBackendNonviewableResponse(
      789, 111, 2, rpc_tuple, rpc_tuples, 0, nonviewable_iids,
      processed_invalidations_up_to)
    self.assertEqual([], rpc_tuples)
    self.assertNotEqual({2: {10002, 10042}}, nonviewable_iids)

  def testHandleBackendNonviewableResponse_Normal(self):
    response_str = (
      '})]\'\n'
      '{'
      ' "nonviewable": [10002, 10042]'
      '}'
      )
    rpc = testing_helpers.Blank(
      get_result=lambda: testing_helpers.Blank(
          content=response_str,
          status_code=200
      ))
    rpc_tuple = (NOW, 2, rpc)
    rpc_tuples = []  # Nothing should be added for this case.
    nonviewable_iids = {}  # At-risk issue IDs should accumlate here, per-shard.
    processed_invalidations_up_to = 12345

    frontendsearchpipeline._HandleBackendNonviewableResponse(
      789, 111, 2, rpc_tuple, rpc_tuples, 2, nonviewable_iids,
      processed_invalidations_up_to)
    self.assertEqual([], rpc_tuples)
    self.assertEqual({2: {10002, 10042}}, nonviewable_iids)

  def testHandleBackendAtRiskResponse_TriggersRetry(self):
    response_str = None
    rpc = testing_helpers.Blank(
      get_result=lambda: testing_helpers.Blank(content=response_str))
    rpc_tuple = (NOW, 2, rpc)
    rpc_tuples = []  # New RPC should be appended here
    nonviewable_iids = {}  # No change here until retry completes.
    processed_invalidations_up_to = 12345

    self.mox.StubOutWithMock(
      frontendsearchpipeline, '_StartBackendNonviewableCall')
    a_fake_rpc = testing_helpers.Blank(callback=None)
    rpc = frontendsearchpipeline._StartBackendNonviewableCall(
      789, 111, 2, processed_invalidations_up_to, failfast=False
      ).AndReturn(a_fake_rpc)
    self.mox.ReplayAll()

    frontendsearchpipeline._HandleBackendNonviewableResponse(
      789, 111, 2, rpc_tuple, rpc_tuples, 2, nonviewable_iids,
      processed_invalidations_up_to)
    self.mox.VerifyAll()
    _, retry_shard_id, retry_rpc = rpc_tuples[0]
    self.assertEqual(2, retry_shard_id)
    self.assertIsNotNone(retry_rpc.callback)
    self.assertEqual(a_fake_rpc, retry_rpc)
    self.assertEqual({}, nonviewable_iids)

  def testSortIssues(self):
    services = service_manager.Services(
        cache_manager=fake.CacheManager())
    sorting.InitializeArtValues(services)

    issue_1 = fake.MakeTestIssue(
      789, 1, 'one', 'New', 111, labels=['Priority-High'])
    issue_2 = fake.MakeTestIssue(
      789, 2, 'two', 'New', 111, labels=['Priority-Low'])
    issue_3 = fake.MakeTestIssue(
      789, 3, 'three', 'New', 111, labels=['Priority-Medium'])
    issues = [issue_1, issue_2, issue_3]
    config = tracker_bizobj.MakeDefaultProjectIssueConfig(789)

    sorted_issues = frontendsearchpipeline._SortIssues(
        issues, config, {}, '', 'priority')

    self.assertEqual(
      [issue_1, issue_3, issue_2],  # Order is high, medium, low.
      sorted_issues)


class FrontendSearchPipelineShardMethodsTest(unittest.TestCase):

  def setUp(self):
    self.sharded_iids = {
      (0, 'p:v'): [10, 20, 30, 40, 50],
      (1, 'p:v'): [21, 41, 61, 81],
      (2, 'p:v'): [42, 52, 62, 72, 102],
      (3, 'p:v'): [],
      }

  def testTotalLength_Empty(self):
    """If there were no results, the length of the sharded list is zero."""
    self.assertEqual(0, frontendsearchpipeline._TotalLength({}))

  def testTotalLength_Normal(self):
    """The length of the sharded list is the sum of the shard lengths."""
    self.assertEqual(
        14, frontendsearchpipeline._TotalLength(self.sharded_iids))

  def testReverseShards_Empty(self):
    """Reversing an empty sharded list is still empty."""
    empty_sharded_iids = {}
    frontendsearchpipeline._ReverseShards(empty_sharded_iids)
    self.assertEqual({}, empty_sharded_iids)

  def testReverseShards_Normal(self):
    """Reversing a sharded list reverses each shard."""
    frontendsearchpipeline._ReverseShards(self.sharded_iids)
    self.assertEqual(
        {(0, 'p:v'): [50, 40, 30, 20, 10],
         (1, 'p:v'): [81, 61, 41, 21],
         (2, 'p:v'): [102, 72, 62, 52, 42],
         (3, 'p:v'): [],
         },
        self.sharded_iids)

  def testTrimShardedIIDs_Empty(self):
    """If the sharded list is empty, trimming it makes no change."""
    empty_sharded_iids = {}
    frontendsearchpipeline._TrimEndShardedIIDs(empty_sharded_iids, [], 12)
    self.assertEqual({}, empty_sharded_iids)

    frontendsearchpipeline._TrimEndShardedIIDs(
        empty_sharded_iids,
        [(100, (0, 'p:v')), (88, (8, 'p:v')), (99, (9, 'p:v'))],
        12)
    self.assertEqual({}, empty_sharded_iids)

  def testTrimShardedIIDs_NoSamples(self):
    """If there are no samples, we don't trim off any IIDs."""
    orig_sharded_iids = {
      shard_id: iids[:] for shard_id, iids in self.sharded_iids.items()}
    num_trimmed = frontendsearchpipeline._TrimEndShardedIIDs(
        self.sharded_iids, [], 12)
    self.assertEqual(0, num_trimmed)
    self.assertEqual(orig_sharded_iids, self.sharded_iids)

    num_trimmed = frontendsearchpipeline._TrimEndShardedIIDs(
        self.sharded_iids, [], 1)
    self.assertEqual(0, num_trimmed)
    self.assertEqual(orig_sharded_iids, self.sharded_iids)

  def testTrimShardedIIDs_Normal(self):
    """The first 3 samples contribute all needed IIDs, so trim off the rest."""
    samples = [(30, (0, 'p:v')), (41, (1, 'p:v')), (62, (2, 'p:v')),
               (40, (0, 'p:v')), (81, (1, 'p:v'))]
    num_trimmed = frontendsearchpipeline._TrimEndShardedIIDs(
        self.sharded_iids, samples, 5)
    self.assertEqual(2 + 1 + 0 + 0, num_trimmed)
    self.assertEqual(
        {  # shard_id: iids before lower-bound + iids before 1st excess sample.
         (0, 'p:v'): [10, 20] + [30],
         (1, 'p:v'): [21] + [41, 61],
         (2, 'p:v'): [42, 52] + [62, 72, 102],
         (3, 'p:v'): [] + []},
        self.sharded_iids)

  def testCalcSamplePositions_Empty(self):
    sharded_iids = {0: []}
    samples = []
    self.assertEqual(
      [], frontendsearchpipeline._CalcSamplePositions(sharded_iids, samples))

    sharded_iids = {0: [10, 20, 30, 40]}
    samples = []
    self.assertEqual(
      [], frontendsearchpipeline._CalcSamplePositions(sharded_iids, samples))

    sharded_iids = {0: []}
    # E.g., the IIDs 2 and 4 might have been trimmed out in the forward phase.
    # But we still have them in the list for the backwards phase, and they
    # should just not contribute anything to the result.
    samples = [(2, (2, 'p:v')), (4, (4, 'p:v'))]
    self.assertEqual(
      [], frontendsearchpipeline._CalcSamplePositions(sharded_iids, samples))

  def testCalcSamplePositions_Normal(self):
    samples = [(30, (0, 'p:v')), (41, (1, 'p:v')), (62, (2, 'p:v')),
               (40, (0, 'p:v')), (81, (1, 'p:v'))]
    self.assertEqual(
      [(30, (0, 'p:v'), 2),
       (41, (1, 'p:v'), 1),
       (62, (2, 'p:v'), 2),
       (40, (0, 'p:v'), 3),
       (81, (1, 'p:v'), 3)],
      frontendsearchpipeline._CalcSamplePositions(self.sharded_iids, samples))