store/tikv: fix unstable tests in snapshot_fail_test.go (#22916)

session/session_fail_test.go

@@ -111,10 +111,13 @@ func (s *testSessionSerialSuite) TestAutoCommitNeedNotLinearizability(c *C) {
 	tk.MustExec(`create table t1 (c int)`)
 
 	c.Assert(failpoint.Enable("github.com/pingcap/tidb/store/tikv/getMinCommitTSFromTSO", `panic`), IsNil)
-	defer failpoint.Disable("github.com/pingcap/tidb/store/tikv/getMinCommitTSFromTSO")
+	defer func() {
+		c.Assert(failpoint.Disable("github.com/pingcap/tidb/store/tikv/getMinCommitTSFromTSO"), IsNil)
+	}()
+
+	c.Assert(tk.Se.GetSessionVars().SetSystemVar("tidb_enable_async_commit", "1"), IsNil)
+	c.Assert(tk.Se.GetSessionVars().SetSystemVar("tidb_guarantee_linearizability", "1"), IsNil)
 
-	tk.Se.GetSessionVars().SetSystemVar("tidb_enable_async_commit", "1")
-	tk.Se.GetSessionVars().SetSystemVar("tidb_guarantee_linearizability", "1")
 	// Auto-commit transactions don't need to get minCommitTS from TSO
 	tk.MustExec("INSERT INTO t1 VALUES (1)")
 
@@ -141,7 +144,7 @@ func (s *testSessionSerialSuite) TestAutoCommitNeedNotLinearizability(c *C) {
 
 	// Same for 1PC
 	tk.MustExec("set autocommit = 1")
-	tk.Se.GetSessionVars().SetSystemVar("tidb_enable_1pc", "1")
+	c.Assert(tk.Se.GetSessionVars().SetSystemVar("tidb_enable_1pc", "1"), IsNil)
 	tk.MustExec("INSERT INTO t1 VALUES (4)")
 
 	tk.MustExec("BEGIN")

store/gcworker/gc_worker_test.go

@@ -924,10 +924,11 @@ func (s *testGCWorkerSuite) TestResolveLockRangeMeetRegionEnlargeCausedByRegionM
 			mCluster := s.cluster.(*mocktikv.Cluster)
 			mCluster.Merge(s.initRegion.regionID, region2)
 			regionMeta, _ := mCluster.GetRegion(s.initRegion.regionID)
-			s.tikvStore.GetRegionCache().OnRegionEpochNotMatch(
+			err := s.tikvStore.GetRegionCache().OnRegionEpochNotMatch(
 				tikv.NewNoopBackoff(context.Background()),
 				&tikv.RPCContext{Region: regionID, Store: &tikv.Store{}},
 				[]*metapb.Region{regionMeta})
+			c.Assert(err, IsNil)
 			// also let region1 contains all 4 locks
 			s.gcWorker.testingKnobs.scanLocks = func(key []byte, regionID uint64) []*tikv.Lock {
 				if regionID == s.initRegion.regionID {

store/tikv/snapshot_fail_test.go

@@ -43,11 +43,27 @@ func (s *testSnapshotFailSuite) TearDownSuite(c *C) {
 	s.OneByOneSuite.TearDownSuite(c)
 }
 
+func (s *testSnapshotFailSuite) cleanup(c *C) {
+	txn, err := s.store.Begin()
+	c.Assert(err, IsNil)
+	iter, err := txn.Iter(kv.Key(""), kv.Key(""))
+	c.Assert(err, IsNil)
+	for iter.Valid() {
+		err = txn.Delete(iter.Key())
+		c.Assert(err, IsNil)
+		err = iter.Next()
+		c.Assert(err, IsNil)
+	}
+	c.Assert(txn.Commit(context.TODO()), IsNil)
+}
+
 func (s *testSnapshotFailSuite) TestBatchGetResponseKeyError(c *C) {
 	// Meaningless to test with tikv because it has a mock key error
 	if *WithTiKV {
 		return
 	}
+	defer s.cleanup(c)
+
 	// Put two KV pairs
 	txn, err := s.store.Begin()
 	c.Assert(err, IsNil)
@@ -75,6 +91,8 @@ func (s *testSnapshotFailSuite) TestScanResponseKeyError(c *C) {
 	if *WithTiKV {
 		return
 	}
+	defer s.cleanup(c)
+
 	// Put two KV pairs
 	txn, err := s.store.Begin()
 	c.Assert(err, IsNil)
@@ -120,6 +138,8 @@ func (s *testSnapshotFailSuite) TestScanResponseKeyError(c *C) {
 }
 
 func (s *testSnapshotFailSuite) TestRetryPointGetWithTS(c *C) {
+	defer s.cleanup(c)
+
 	snapshot := s.store.GetSnapshot(kv.MaxVersion)
 	c.Assert(failpoint.Enable("github.com/pingcap/tidb/store/tikv/snapshotGetTSAsync", `pause`), IsNil)
 	ch := make(chan error)
@@ -138,13 +158,14 @@ func (s *testSnapshotFailSuite) TestRetryPointGetWithTS(c *C) {
 	c.Assert(failpoint.Enable("github.com/pingcap/tidb/store/tikv/asyncCommitDoNothing", `return`), IsNil)
 	committer, err := newTwoPhaseCommitterWithInit(txn.(*tikvTxn), 1)
 	c.Assert(err, IsNil)
-	// Sets its minCommitTS to a large value, so the lock can be actually ignored.
-	committer.minCommitTS = committer.startTS + (1 << 28)
+	// Sets its minCommitTS to one second later, so the lock will be ignored by point get.
+	committer.minCommitTS = committer.startTS + (1000 << 18)
 	err = committer.execute(context.Background())
 	c.Assert(err, IsNil)
-	c.Assert(failpoint.Disable("github.com/pingcap/tidb/store/tikv/asyncCommitDoNothing"), IsNil)
 	c.Assert(failpoint.Disable("github.com/pingcap/tidb/store/tikv/snapshotGetTSAsync"), IsNil)
 
 	err = <-ch
 	c.Assert(err, ErrorMatches, ".*key not exist")
+
+	c.Assert(failpoint.Disable("github.com/pingcap/tidb/store/tikv/asyncCommitDoNothing"), IsNil)
 }