var trimFuncTests = []TrimFuncTest{
	{isSpace, space + " hello " + space,
		[]byte("hello"),
		[]byte("hello " + space),
		[]byte(space + " hello")},
	{isDigit, "\u0e50\u0e5212hello34\u0e50\u0e51",
		[]byte("hello"),
		[]byte("hello34\u0e50\u0e51"),
		[]byte("\u0e50\u0e5212hello")},
	{isUpper, "\u2C6F\u2C6F\u2C6F\u2C6FABCDhelloEF\u2C6F\u2C6FGH\u2C6F\u2C6F",
		[]byte("hello"),
		[]byte("helloEF\u2C6F\u2C6FGH\u2C6F\u2C6F"),

	b = bytes.TrimPrefix(b, []byte("Goodbye,"))
	b = bytes.TrimPrefix(b, []byte("See ya,"))
	fmt.Printf("Hello%s", b)
	// Output: Hello, world!
}

func ExampleTrimSpace() {
	fmt.Printf("%s", bytes.TrimSpace([]byte(" \t\n a lone gopher \n\t\r\n")))
	// Output: a lone gopher
}

func ExampleTrimSuffix() {
	var b = []byte("Hello, goodbye, etc!")
	b = bytes.TrimSuffix(b, []byte("goodbye, etc!"))

)

// Model specify the model you would like to run db operations
//
//	// update all users's name to `hello`
//	db.Model(&User{}).Update("name", "hello")
//	// if user's primary key is non-blank, will use it as condition, then will only update that user's name to `hello`
//	db.Model(&user).Update("name", "hello")
func (db *DB) Model(value interface{}) (tx *DB) {
	tx = db.getInstance()
	tx.Statement.Model = value
	return
}

	// local to remote
	remoteConn := local.Connection(remoteHost)
	remoteConn.WaitForConnect(context.Background())
	defer testlogger.T.SetErrorTB(t)()

	t.Run("localToRemote", func(t *testing.T) {
		const testPayload = "Hello Grid World!"

		start := time.Now()
		resp, err := remoteConn.Request(context.Background(), handlerTest, []byte(testPayload))
		errFatal(err)
		if string(resp) != testPayload {

		{
			objectName:         "test",
			data:               []byte("Hello, World"),
			expectedRespStatus: http.StatusForbidden,
			accessKey:          "",
			secretKey:          "",
			malformedBody:      false,
		},
		// Bad case malformed input.
		{
			objectName:         "test",
			data:               []byte("Hello, World"),
			expectedRespStatus: http.StatusBadRequest,

		// Short Content-Md5 header.
		{mustNewSignedShortMD5Request(http.MethodPut, "http://127.0.0.1:9000/", 5, bytes.NewReader([]byte("hello")), t), ErrInvalidDigest},
		// When request is properly signed, but has bad Content-MD5 header.
		{mustNewSignedBadMD5Request(http.MethodPut, "http://127.0.0.1:9000/", 5, bytes.NewReader([]byte("hello")), t), ErrBadDigest},

	z.conns.addConn(conn)
	defer z.conns.deleteConn(conn)

	// get hello message from ztunnel
	m, _, err := readProto[zdsapi.ZdsHello](conn.u, readWriteDeadline, nil)
	if err != nil {
		return err
	}
	log.Infof("received hello from ztunnel. %v", m.Version)
	log.Debug("sending snapshot to ztunnel")
	if err := z.sendSnapshot(ctx, conn); err != nil {
		return err

					n := 0
					var latency int64
					managers := grid.Managers
					hosts := grid.Hosts
					req := testRequest{
						Num:    rng.Int(),
						String: "hello",
					}
					for pb.Next() {
						// Pick a random manager.
						src, dst := rng.Intn(len(managers)), rng.Intn(len(managers))
						if src == dst {
							dst = (dst + 1) % len(managers)
						}

	c.Assert(response.ContentLength, int64(len([]byte("hello world"))))
	var buffer2 bytes.Buffer
	// retrieve the contents of response body.
	n, err := io.Copy(&buffer2, response.Body)
	c.Assert(err, nil)
	c.Assert(n, int64(len([]byte("hello world"))))
	// asserted the contents of the fetched object with the expected result.
	c.Assert(true, bytes.Equal(buffer2.Bytes(), []byte("hello world")))

	}

	type ColumnStruct2 struct {
		ID    int    `gorm:"primarykey;default:auto_random()"`
		Name  string `gorm:"size:100"`
		Code  string `gorm:"unique;comment:my code2;default:hello"`
		Code2 string `gorm:"comment:my code2;default:hello"`
	}

	if err := DB.Table("column_structs").Migrator().AlterColumn(&ColumnStruct{}, "Name"); err != nil {
		t.Fatalf("no error should happened when alter column, but got %v", err)
	}