Revert "validation_pool: pool.changes -> pool.candidates, pool.applied."upstream

This reverts commit ff627b430f16161de5d62b390733984692329fe0.

BUG=chromium:557314
TEST=None

Change-Id: I057df80e2208fbce020e878d677e8b1e5f9656d0
Reviewed-on: https://chromium-review.googlesource.com/312965
Reviewed-by: Aviv Keshet <akeshet@chromium.org>
Reviewed-by: Don Garrett <dgarrett@chromium.org>
Tested-by: Simran Basi <sbasi@chromium.org>

7 files changed, 79 insertions, 105 deletions

diff --git a/cbuildbot/lkgm_manager.py b/cbuildbot/lkgm_manager.py
index a2303f0d9..947b7b25e 100644
--- a/cbuildbot/lkgm_manager.py
+++ b/cbuildbot/lkgm_manager.py
@@ -269,7 +269,7 @@ class LKGMManager(manifest_version.BuildSpecsManager):
           not config_lib.IsPFQType(self.build_type)):
         return None
 
-      self._AddPatchesToManifest(new_manifest, validation_pool.applied)
+      self._AddPatchesToManifest(new_manifest, validation_pool.changes)
 
       # Add info about the last known good version to the manifest. This will
       # be used by slaves to calculate what artifacts from old builds are safe
@@ -288,7 +288,7 @@ class LKGMManager(manifest_version.BuildSpecsManager):
 
         # If we don't have any valid changes to test, make sure the checkout
         # is at least different.
-        if ((not validation_pool or not validation_pool.applied) and
+        if ((not validation_pool or not validation_pool.changes) and
             not self.force and self.HasCheckoutBeenBuilt()):
           return None
 
diff --git a/cbuildbot/stages/completion_stages.py b/cbuildbot/stages/completion_stages.py
index e18eaf6d0..e1467d3f0 100644
--- a/cbuildbot/stages/completion_stages.py
+++ b/cbuildbot/stages/completion_stages.py
@@ -640,7 +640,7 @@ class CommitQueueCompletionStage(MasterSlaveSyncCompletionStage):
     messages = self._GetFailedMessages(failing)
     self.SendInfraAlertIfNeeded(failing, inflight, no_stat)
 
-    changes = self.sync_stage.pool.applied
+    changes = self.sync_stage.pool.changes
 
     do_partial_submission = self._ShouldSubmitPartialPool()
 
diff --git a/cbuildbot/stages/completion_stages_unittest.py b/cbuildbot/stages/completion_stages_unittest.py
index af5ac8714..7e900be31 100644
--- a/cbuildbot/stages/completion_stages_unittest.py
+++ b/cbuildbot/stages/completion_stages_unittest.py
@@ -352,7 +352,7 @@ class BaseCommitQueueCompletionStageTest(
     """
     sync_stage = sync_stages.CommitQueueSyncStage(self._run)
     sync_stage.pool = mock.MagicMock()
-    sync_stage.pool.applied = self.changes
+    sync_stage.pool.changes = self.changes
     sync_stage.pool.tree_was_open = tree_was_open
 
     sync_stage.pool.handle_failure_mock = self.PatchObject(
diff --git a/cbuildbot/stages/sync_stages.py b/cbuildbot/stages/sync_stages.py
index e682f427a..8eb6ce77f 100644
--- a/cbuildbot/stages/sync_stages.py
+++ b/cbuildbot/stages/sync_stages.py
@@ -1058,7 +1058,7 @@ class CommitQueueSyncStage(MasterSlaveLKGMSyncStage):
     else:
       ManifestVersionedSyncStage.PerformStage(self)
 
-    self.WriteChangesToMetadata(self.pool.applied)
+    self.WriteChangesToMetadata(self.pool.changes)
 
 
 class PreCQSyncStage(SyncStage):
@@ -1091,14 +1091,14 @@ class PreCQSyncStage(SyncStage):
     self.pool = validation_pool.ValidationPool.AcquirePreCQPool(
         self._run.config.overlays, self._build_root,
         self._run.buildnumber, self._run.config.name,
-        dryrun=self._run.options.debug_forced, candidates=self.patches,
+        dryrun=self._run.options.debug_forced, changes=self.patches,
         builder_run=self._run)
     self.pool.ApplyPoolIntoRepo()
 
-    if len(self.pool.applied) == 0 and self.patches:
+    if len(self.pool.changes) == 0 and self.patches:
       cros_build_lib.Die('No changes have been applied.')
 
-    changes = self.pool.applied or self.patches
+    changes = self.pool.changes or self.patches
     self.WriteChangesToMetadata(changes)
 
 class PreCQLauncherStage(SyncStage):
diff --git a/cbuildbot/stages/sync_stages_unittest.py b/cbuildbot/stages/sync_stages_unittest.py
index f79a9069f..e2dc8297b 100644
--- a/cbuildbot/stages/sync_stages_unittest.py
+++ b/cbuildbot/stages/sync_stages_unittest.py
@@ -526,38 +526,38 @@ class MasterCQSyncTest(MasterCQSyncTestCase):
   def testCommitNonManifestChange(self):
     """See MasterCQSyncTestCase"""
     changes = self._testCommitNonManifestChange()
-    self.assertItemsEqual(self.sync_stage.pool.candidates, changes)
+    self.assertItemsEqual(self.sync_stage.pool.changes, changes)
     self.assertItemsEqual(self.sync_stage.pool.non_manifest_changes, [])
 
   def testFailedCommitOfNonManifestChange(self):
     """See MasterCQSyncTestCase"""
     changes = self._testFailedCommitOfNonManifestChange()
-    self.assertItemsEqual(self.sync_stage.pool.candidates, changes)
+    self.assertItemsEqual(self.sync_stage.pool.changes, changes)
     self.assertItemsEqual(self.sync_stage.pool.non_manifest_changes, [])
 
   def testCommitManifestChange(self):
     """See MasterCQSyncTestCase"""
     changes = self._testCommitManifestChange()
-    self.assertItemsEqual(self.sync_stage.pool.candidates, changes)
+    self.assertItemsEqual(self.sync_stage.pool.changes, changes)
     self.assertItemsEqual(self.sync_stage.pool.non_manifest_changes, [])
 
   def testCommitManifestChangeWithoutPreCQ(self):
     """Changes get ignored if they aren't approved by pre-cq."""
     self._testCommitManifestChange(pre_cq_status=None)
-    self.assertItemsEqual(self.sync_stage.pool.candidates, [])
+    self.assertItemsEqual(self.sync_stage.pool.changes, [])
     self.assertItemsEqual(self.sync_stage.pool.non_manifest_changes, [])
 
   def testCommitManifestChangeWithoutPreCQAndOldPatches(self):
     """Changes get tested without pre-cq if the approval_timestamp is old."""
     changes = self._testCommitManifestChange(pre_cq_status=None,
                                              approval_timestamp=0)
-    self.assertItemsEqual(self.sync_stage.pool.candidates, changes)
+    self.assertItemsEqual(self.sync_stage.pool.changes, changes)
     self.assertItemsEqual(self.sync_stage.pool.non_manifest_changes, [])
 
   def testDefaultSync(self):
     """See MasterCQSyncTestCase"""
     changes = self._testDefaultSync()
-    self.assertItemsEqual(self.sync_stage.pool.candidates, changes)
+    self.assertItemsEqual(self.sync_stage.pool.changes, changes)
     self.assertItemsEqual(self.sync_stage.pool.non_manifest_changes, [])
 
   def testReload(self):
@@ -565,7 +565,7 @@ class MasterCQSyncTest(MasterCQSyncTestCase):
     # Use zero patches because mock patches can't be pickled.
     changes = self.PerformSync(num_patches=0, runs=0)
     self.ReloadPool()
-    self.assertItemsEqual(self.sync_stage.pool.candidates, changes)
+    self.assertItemsEqual(self.sync_stage.pool.changes, changes)
     self.assertItemsEqual(self.sync_stage.pool.non_manifest_changes, [])
 
   def testTreeClosureBlocksCommit(self):
@@ -579,7 +579,7 @@ class MasterCQSyncTest(MasterCQSyncTestCase):
     gerrit.GerritHelper.Query.assert_called_with(
         mock.ANY, constants.THROTTLED_CQ_READY_QUERY[0],
         sort='lastUpdated')
-    self.assertItemsEqual(self.sync_stage.pool.candidates, changes)
+    self.assertItemsEqual(self.sync_stage.pool.changes, changes)
     self.assertItemsEqual(self.sync_stage.pool.non_manifest_changes, [])
 
 
diff --git a/cbuildbot/validation_pool.py b/cbuildbot/validation_pool.py
index 4c0bde02f..15f18e9d0 100644
--- a/cbuildbot/validation_pool.py
+++ b/cbuildbot/validation_pool.py
@@ -1120,9 +1120,9 @@ class ValidationPool(object):
 
 
   def __init__(self, overlays, build_root, build_number, builder_name,
-               is_master, dryrun, candidates=None, non_os_changes=None,
+               is_master, dryrun, changes=None, non_os_changes=None,
                conflicting_changes=None, pre_cq_trybot=False,
-               tree_was_open=True, applied=None, builder_run=None):
+               tree_was_open=True, _applied=None, builder_run=None):
     """Initializes an instance by setting default variables to instance vars.
 
     Generally use AcquirePool as an entry pool to a pool rather than this
@@ -1136,7 +1136,7 @@ class ValidationPool(object):
       is_master: True if this is the master builder for the Commit Queue.
       dryrun: If set to True, do not submit anything to Gerrit.
     Optional Args:
-      candidates: List of changes to consider validating.
+      changes: List of changes for this validation pool.
       non_os_changes: List of changes that are part of this validation
         pool but aren't part of the cros checkout.
       conflicting_changes: Changes that failed to apply but we're keeping around
@@ -1144,7 +1144,8 @@ class ValidationPool(object):
       pre_cq_trybot: If set to True, this is a Pre-CQ trybot. (Note: The Pre-CQ
         launcher is NOT considered a Pre-CQ trybot.)
       tree_was_open: Whether the tree was open when the pool was created.
-      applied: List of CLs that have been applied to the current repo.
+      applied: List of CLs that have been applied to the current repo. Not
+        yet used, but needs to be here for pickling compatibility.
       builder_run: BuilderRun instance used to fetch cidb handle and metadata
         instance. Please note due to the pickling logic, this MUST be the last
         kwarg listed.
@@ -1166,9 +1167,7 @@ class ValidationPool(object):
       raise ValueError("Invalid builder_name: %r" % (builder_name,))
 
     for changes_name, changes_value in (
-        ('candidates', candidates),
-        ('non_os_changes', non_os_changes),
-        ('applied', applied)):
+        ('changes', changes), ('non_os_changes', non_os_changes)):
       if not changes_value:
         continue
       if not all(isinstance(x, cros_patch.GitRepoPatch) for x in changes_value):
@@ -1196,17 +1195,8 @@ class ValidationPool(object):
       self.queue = 'The Commit Queue'
 
     # See optional args for types of changes.
-    self.candidates = candidates or []
+    self.changes = changes or []
     self.non_manifest_changes = non_os_changes or []
-
-    # TODO(dgarrett): Remove this if block after pickle changes settle down.
-    if applied is None:
-      # If we received a pickle from an older version, it will use the
-      # default applied value. All candidates were already applied.
-      applied = self.candidates[:]
-
-    self.applied = applied or []
-
     # Note, we hold onto these CLs since they conflict against our current CLs
     # being tested; if our current ones succeed, we notify the user to deal
     # w/ the conflict.  If the CLs we're testing fail, then there is no
@@ -1251,12 +1241,11 @@ class ValidationPool(object):
         (
             self._overlays,
             self.build_root, self._build_number, self._builder_name,
-            self.is_master, self.dryrun, self.candidates,
+            self.is_master, self.dryrun, self.changes,
             self.non_manifest_changes,
             self.changes_that_failed_to_apply_earlier,
             self.pre_cq_trybot,
-            self.tree_was_open,
-            self.applied))
+            self.tree_was_open))
 
   @classmethod
   @failures_lib.SetFailureType(failures_lib.BuilderFailure)
@@ -1309,14 +1298,14 @@ class ValidationPool(object):
 
       changes, non_manifest_changes = ValidationPool._FilterNonCrosProjects(
           changes, git.ManifestCheckout.Cached(self.build_root))
-      self.candidates.extend(changes)
+      self.changes.extend(changes)
       self.non_manifest_changes.extend(non_manifest_changes)
 
     # Filter out unwanted changes.
-    self.candidates, self.non_manifest_changes = change_filter(
-        self, self.candidates, self.non_manifest_changes)
+    self.changes, self.non_manifest_changes = change_filter(
+        self, self.changes, self.non_manifest_changes)
 
-    return self.candidates or self.non_manifest_changes
+    return self.changes or self.non_manifest_changes
 
   @classmethod
   def AcquirePool(cls, overlays, repo, build_number, builder_name, query,
@@ -1465,7 +1454,7 @@ class ValidationPool(object):
         attr_dict[name] = pc.getAttribute(name)
       patch = cros_patch.GerritFetchOnlyPatch.FromAttrDict(attr_dict)
 
-      self.candidates.append(patch)
+      self.changes.append(patch)
 
   @classmethod
   def AcquirePoolFromManifest(cls, manifest, overlays, repo, build_number,
@@ -1630,8 +1619,6 @@ class ValidationPool(object):
   def FilterChangesForThrottledTree(self):
     """Apply Throttled Tree logic to select patch candidates.
 
-    This should be called before any CLs are applied.
-
     If the tree is throttled, we only test a random subset of our candidate
     changes. Call this to select that subset, and throw away unrelated changes.
 
@@ -1640,14 +1627,12 @@ class ValidationPool(object):
     if self.tree_was_open:
       return
 
-    # By filtering the candidates before any calls to Apply, we can make sure
-    # that repeated calls to Apply always consider the same list of candidates.
     fail_streak = self._GetFailStreak()
-    test_pool_size = max(1, len(self.candidates) / (2**fail_streak))
-    random.shuffle(self.candidates)
-    self.candidates = self.candidates[:test_pool_size]
+    test_pool_size = max(1, len(self.changes) / (2**fail_streak))
+    random.shuffle(self.changes)
+    self.changes = self.changes[:test_pool_size]
 
-  def ApplyPoolIntoRepo(self, manifest=None, filter_fn=lambda p: True):
+  def ApplyPoolIntoRepo(self, manifest=None):
     """Applies changes from pool into the directory specified by the buildroot.
 
     This method applies changes in the order specified. If the build
@@ -1655,13 +1640,6 @@ class ValidationPool(object):
     order. Otherwise, the changes should already be listed in an order
     that will not break the dependency order.
 
-    It is safe to call this method more than once, probably with different
-    filter functions. A given patch will never be applied more than  once.
-
-    Args:
-      manifest: A manifest object to use for mapping projects to repositories.
-      filter_fn: Takes a patch argument, returns bool for 'should apply'.
-
     Returns:
       True if we managed to apply any changes.
     """
@@ -1674,12 +1652,9 @@ class ValidationPool(object):
 
     if self.is_master:
       try:
-        candidates = [c for c in self.candidates if
-                      c not in self.applied and filter_fn(c)]
-
         # pylint: disable=E1123
         applied, failed_tot, failed_inflight = patch_series.Apply(
-            candidates, manifest=manifest)
+            self.changes, manifest=manifest)
       except (KeyboardInterrupt, RuntimeError, SystemExit):
         raise
       except Exception as e:
@@ -1692,9 +1667,9 @@ class ValidationPool(object):
             'commit queue does not go into an infinite loop retrying '
             'patches.' % (e,)
         )
-        links = cros_patch.GetChangesAsString(self.candidates)
+        links = cros_patch.GetChangesAsString(self.changes)
         logging.error('%s\nAffected Patches are: %s', msg, links)
-        errors = [InternalCQError(patch, msg) for patch in self.candidates]
+        errors = [InternalCQError(patch, msg) for patch in self.changes]
         self._HandleApplyFailure(errors)
         raise
 
@@ -1716,7 +1691,7 @@ class ValidationPool(object):
       # Slaves do not need to create transactions and should simply
       # apply the changes serially, based on the order that the
       # changes were listed on the manifest.
-      for change in self.candidates:
+      for change in self.changes:
         try:
           # pylint: disable=E1123
           patch_series.ApplyChange(change, manifest=manifest)
@@ -1758,9 +1733,9 @@ class ValidationPool(object):
         self._HandleFailedToApplyDueToInflightConflict(x.patch)
 
     self.changes_that_failed_to_apply_earlier.extend(failed_inflight)
-    self.applied.extend(applied)
+    self.changes = applied
 
-    return bool(applied)
+    return bool(self.changes)
 
   @staticmethod
   def Load(filename, builder_run=None):
@@ -2348,7 +2323,7 @@ class ValidationPool(object):
     # a CQ run (since the submit state has changed, we have no way of
     # knowing).  They *likely* will still fail, but this approach tries
     # to minimize wasting the developers time.
-    submitted, errors = self.SubmitChanges(self.applied,
+    submitted, errors = self.SubmitChanges(self.changes,
                                            check_tree_open=check_tree_open,
                                            throttled_ok=throttled_ok,
                                            reason=reason)
@@ -2478,7 +2453,7 @@ class ValidationPool(object):
         not sane, none of the changes will have their CommitReady bit modified.
     """
     if changes is None:
-      changes = self.applied
+      changes = self.changes
 
     logging.info('Validation timed out for all changes.')
     base_msg = ('%(queue)s timed out while verifying your change in '
@@ -2543,7 +2518,7 @@ class ValidationPool(object):
         self._InsertCLActionToDatabase(change, constants.CL_ACTION_VERIFIED)
 
     # Process the changes in parallel.
-    inputs = [[change] for change in self.applied]
+    inputs = [[change] for change in self.changes]
     parallel.RunTasksInProcessPool(ProcessChange, inputs)
 
   def _HandleCouldNotSubmit(self, change, error=''):
@@ -2700,7 +2675,7 @@ class ValidationPool(object):
         status. If not None, this implies there were infrastructure issues.
     """
     if changes is None:
-      changes = self.applied
+      changes = self.changes
 
     candidates = []
 
diff --git a/cbuildbot/validation_pool_unittest.py b/cbuildbot/validation_pool_unittest.py
index fbf47e1f1..3fab2d100 100644
--- a/cbuildbot/validation_pool_unittest.py
+++ b/cbuildbot/validation_pool_unittest.py
@@ -652,7 +652,7 @@ def MakePool(overlays=constants.PUBLIC_OVERLAYS, build_number=1,
              builder_name='foon', is_master=True, dryrun=True,
              fake_db=None, **kwargs):
   """Helper for creating ValidationPool objects for tests."""
-  kwargs.setdefault('candidates', [])
+  kwargs.setdefault('changes', [])
   build_root = kwargs.pop('build_root', '/fake_root')
 
   builder_run = FakeBuilderRun(fake_db)
@@ -785,7 +785,7 @@ class ValidationFailureOrTimeout(MoxBase):
 
   def setUp(self):
     self._patches = self.GetPatches(3)
-    self._pool = MakePool(applied=self._patches, fake_db=self.fake_db)
+    self._pool = MakePool(changes=self._patches, fake_db=self.fake_db)
 
     self.PatchObject(
         triage_lib.CalculateSuspects, 'FindSuspects',
@@ -878,8 +878,8 @@ class TestCoreLogic(MoxBase):
     return cros_patch.ApplyPatchException(patch, inflight=inflight)
 
   def GetPool(self, changes, applied=(), tot=(), inflight=(), **kwargs):
-    pool = self.MakePool(
-        candidates=changes, applied=[], fake_db=self.fake_db, **kwargs)
+
+    pool = self.MakePool(changes=changes, fake_db=self.fake_db, **kwargs)
     applied = list(applied)
     tot = [self.MakeFailure(x, inflight=False) for x in tot]
     inflight = [self.MakeFailure(x, inflight=True) for x in inflight]
@@ -909,7 +909,7 @@ class TestCoreLogic(MoxBase):
     """Verifies that slave calls ApplyChange() directly for each patch."""
     slave_pool = self.MakePool(is_master=False)
     patches = self.GetPatches(3)
-    slave_pool.candidates = patches
+    slave_pool.changes = patches
     for patch in patches:
       # pylint: disable=E1120, E1123
       validation_pool.PatchSeries.ApplyChange(patch, manifest=mox.IgnoreArg())
@@ -920,7 +920,7 @@ class TestCoreLogic(MoxBase):
 
   def runApply(self, pool, result):
     self.assertEqual(result, pool.ApplyPoolIntoRepo())
-    self.assertEqual(pool.applied, pool._test_data[1])
+    self.assertEqual(pool.changes, pool._test_data[1])
     failed_inflight = pool.changes_that_failed_to_apply_earlier
     expected_inflight = set(pool._test_data[3])
     # Intersect the results, since it's possible there were results failed
@@ -928,6 +928,8 @@ class TestCoreLogic(MoxBase):
     self.assertEqual(set(failed_inflight).intersection(expected_inflight),
                      expected_inflight)
 
+    self.assertEqual(pool.changes, pool._test_data[1])
+
   def testPatchSeriesInteraction(self):
     """Verify the interaction between PatchSeries and ValidationPool.
 
@@ -989,7 +991,7 @@ class TestCoreLogic(MoxBase):
     pool = self.MakePool(dryrun=False, handlers=True)
     patches = self.GetPatches(3)
     failed = self.GetPatches(3)
-    pool.applied = patches[:]
+    pool.changes = patches[:]
     # While we don't do anything w/ these patches, that's
     # intentional; we're verifying that it isn't submitted
     # if there is a failure.
@@ -1122,9 +1124,6 @@ class TestCoreLogic(MoxBase):
     """Test that CQ doesn't loop due to unhandled Exceptions."""
     pool, patches, _failed = self._setUpSubmit()
 
-    pool.candidates = pool.applied
-    pool.applied = []
-
     class MyException(Exception):
       """"Unique Exception used for testing."""
 
@@ -1372,11 +1371,11 @@ class TestCoreLogic(MoxBase):
     self.mox.ReplayAll()
 
     # Perform test.
-    slave_pool = self.MakePool(candidates=patches, tree_was_open=True)
+    slave_pool = self.MakePool(changes=patches, tree_was_open=True)
     slave_pool.FilterChangesForThrottledTree()
 
     # Validate results.
-    self.assertEqual(len(slave_pool.candidates), 4)
+    self.assertEqual(len(slave_pool.changes), 4)
     self.mox.VerifyAll()
     self.mox.ResetAll()
 
@@ -1389,11 +1388,11 @@ class TestCoreLogic(MoxBase):
     self.mox.ReplayAll()
 
     # Perform test.
-    slave_pool = self.MakePool(candidates=patches, tree_was_open=False)
+    slave_pool = self.MakePool(changes=patches, tree_was_open=False)
     slave_pool.FilterChangesForThrottledTree()
 
     # Validate results.
-    self.assertEqual(len(slave_pool.candidates), 2)
+    self.assertEqual(len(slave_pool.changes), 2)
     self.mox.VerifyAll()
     self.mox.ResetAll()
 
@@ -1406,11 +1405,11 @@ class TestCoreLogic(MoxBase):
     self.mox.ReplayAll()
 
     # Perform test.
-    slave_pool = self.MakePool(candidates=patches, tree_was_open=False)
+    slave_pool = self.MakePool(changes=patches, tree_was_open=False)
     slave_pool.FilterChangesForThrottledTree()
 
     # Validate results.
-    self.assertEqual(len(slave_pool.candidates), 1)
+    self.assertEqual(len(slave_pool.changes), 1)
     self.mox.VerifyAll()
     self.mox.ResetAll()
 
@@ -1423,11 +1422,11 @@ class TestCoreLogic(MoxBase):
     self.mox.ReplayAll()
 
     # Perform test.
-    slave_pool = self.MakePool(candidates=patches, tree_was_open=False)
+    slave_pool = self.MakePool(changes=patches, tree_was_open=False)
     slave_pool.FilterChangesForThrottledTree()
 
     # Validate results.
-    self.assertEqual(len(slave_pool.candidates), 1)
+    self.assertEqual(len(slave_pool.changes), 1)
     self.mox.VerifyAll()
 
 
@@ -1496,7 +1495,7 @@ sys.stdout.write(validation_pool_unittest.TestPickling.%s)
         constants.PUBLIC_OVERLAYS,
         '/fake/pathway', 1,
         'testing', True, True,
-        candidates=changes, non_os_changes=non_os,
+        changes=changes, non_os_changes=non_os,
         conflicting_changes=conflicting)
     return pickle.dumps([pool, changes, non_os, conflicting])
 
@@ -1511,7 +1510,7 @@ sys.stdout.write(validation_pool_unittest.TestPickling.%s)
       for s_item, v_item in zip(source, value):
         assert getter(s_item).id == getter(v_item).id
         assert getter(s_item).remote == getter(v_item).remote
-    _f(pool.candidates, changes)
+    _f(pool.changes, changes)
     _f(pool.non_manifest_changes, non_os)
     _f(pool.changes_that_failed_to_apply_earlier, conflicting,
        getter=lambda s: getattr(s, 'patch', s))
@@ -1641,8 +1640,8 @@ class TestCreateDisjointTransactions(MoxBase):
       # the specified length, ignoring any remaining patches.
       expected_plans = [txn[:max_txn_length] for txn in txns]
 
-    pool = MakePool(candidates=patches)
-    plans = pool.CreateDisjointTransactions(None, pool.candidates,
+    pool = MakePool(changes=patches)
+    plans = pool.CreateDisjointTransactions(None, pool.changes,
                                             max_txn_length=max_txn_length)
 
     # If the dependencies are circular, the order of the patches is not
@@ -1666,7 +1665,7 @@ class TestCreateDisjointTransactions(MoxBase):
     notify = self.PatchObject(validation_pool.ValidationPool,
                               'SendNotification')
     remove = self.PatchObject(gerrit.GerritHelper, 'RemoveReady')
-    pool = MakePool(candidates=changes)
+    pool = MakePool(changes=changes)
     plans = pool.CreateDisjointTransactions(None, changes,
                                             max_txn_length=max_txn_length)
     self.assertEqual(plans, [])
@@ -1765,7 +1764,7 @@ class BaseSubmitPoolTestCase(MoxBase):
     self.patches = self.GetPatches(2)
 
   def SetUpPatchPool(self, failed_to_apply=False):
-    pool = MakePool(candidates=self.patches, dryrun=False)
+    pool = MakePool(changes=self.patches, dryrun=False)
     if failed_to_apply:
       # Create some phony errors and add them to the pool.
       errors = []
@@ -1789,7 +1788,7 @@ class BaseSubmitPoolTestCase(MoxBase):
     with mock.patch.object(git.ManifestCheckout, 'Cached', new=mock_manifest):
       if not self.ALL_BUILDS_PASSED:
         actually_rejected = sorted(pool.SubmitPartialPool(
-            pool.candidates, mock.ANY, dict(), [], [], [], reason=reason))
+            pool.changes, mock.ANY, dict(), [], [], [], reason=reason))
       else:
         _, actually_rejected = pool.SubmitChanges(self.patches, reason=reason)
 
@@ -2028,17 +2027,17 @@ class LoadManifestTest(cros_test_lib.TempDirTestCase):
       f.flush()
       self.pool.AddPendingCommitsIntoPool(f.name)
 
-    self.assertEqual(self.pool.candidates[0].owner_email, 'foo@chromium.org')
-    self.assertEqual(self.pool.candidates[0].tracking_branch, 'master')
-    self.assertEqual(self.pool.candidates[0].remote, 'cros')
-    self.assertEqual(self.pool.candidates[0].gerrit_number, '17000')
-    self.assertEqual(self.pool.candidates[0].project, 'chromiumos/taco/bar')
-    self.assertEqual(self.pool.candidates[0].project_url,
+    self.assertEqual(self.pool.changes[0].owner_email, 'foo@chromium.org')
+    self.assertEqual(self.pool.changes[0].tracking_branch, 'master')
+    self.assertEqual(self.pool.changes[0].remote, 'cros')
+    self.assertEqual(self.pool.changes[0].gerrit_number, '17000')
+    self.assertEqual(self.pool.changes[0].project, 'chromiumos/taco/bar')
+    self.assertEqual(self.pool.changes[0].project_url,
                      'https://base_url/chromiumos/taco/bar')
-    self.assertEqual(self.pool.candidates[0].change_id,
+    self.assertEqual(self.pool.changes[0].change_id,
                      'Ieeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee1')
-    self.assertEqual(self.pool.candidates[0].commit,
+    self.assertEqual(self.pool.changes[0].commit,
                      '1ddddddddddddddddddddddddddddddddddddddd')
-    self.assertEqual(self.pool.candidates[0].fail_count, 2)
-    self.assertEqual(self.pool.candidates[0].pass_count, 0)
-    self.assertEqual(self.pool.candidates[0].total_fail_count, 3)
+    self.assertEqual(self.pool.changes[0].fail_count, 2)
+    self.assertEqual(self.pool.changes[0].pass_count, 0)
+    self.assertEqual(self.pool.changes[0].total_fail_count, 3)