executor,store/mockstore: add a test to mock get tso fail (pingcap#8566)

executor/executor_test.go

@@ -3360,3 +3360,15 @@ func (s *testSuite) TestDoSubquery(c *C) {
 	c.Assert(err, IsNil, Commentf("err %v", err))
 	c.Assert(r, IsNil, Commentf("result of Do not empty"))
 }
+
+func (s *testSuite) TestTSOFail(c *C) {
+	tk := testkit.NewTestKit(c, s.store)
+	tk.MustExec(`use test`)
+	tk.MustExec(`drop table if exists t`)
+	tk.MustExec(`create table t(a int)`)
+
+	gofail.Enable("github.com/pingcap/tidb/store/mockstore/mocktikv/mockGetTSFail", `return(true)`)
+	defer gofail.Disable("github.com/pingcap/tidb/store/mockstore/mocktikv/mockGetTSFail")
+	_, err := tk.Exec(`select * from t`)
+	c.Assert(err, NotNil)
+}

store/mockstore/mocktikv/pd.go

@@ -17,6 +17,7 @@ import (
 	"sync"
 	"time"
 
+	"github.com/pingcap/errors"
 	"github.com/pingcap/kvproto/pkg/metapb"
 	"github.com/pingcap/pd/client"
 	"golang.org/x/net/context"
@@ -46,6 +47,11 @@ func (c *pdClient) GetClusterID(ctx context.Context) uint64 {
 }
 
 func (c *pdClient) GetTS(context.Context) (int64, int64, error) {
+	// gofail: var mockGetTSFail bool
+	// if mockGetTSFail {
+	// 	return 0, 0, errors.New("mock get timestamp fail")
+	// }
+
 	tsMu.Lock()
 	defer tsMu.Unlock()
 
@@ -97,7 +103,7 @@ func (c *pdClient) GetStore(ctx context.Context, storeID uint64) (*metapb.Store,
 }
 
 func (c *pdClient) GetAllStores(ctx context.Context) ([]*metapb.Store, error) {
-	panic("unimplemented")
+	panic(errors.New("unimplemented"))
 }
 
 func (c *pdClient) UpdateGCSafePoint(ctx context.Context, safePoint uint64) (uint64, error) {