Gorm BeforeSave is executed twice in transaction

GORM Playground Link

https://github.com/go-gorm/playground/pull/593

Description

When you save a model which BeforeSave is implemented in a transaction, BeforeSave will be executed twice.

package main_test

import (
    "testing"

    "github.com/stretchr/testify/assert"
    "gorm.io/driver/mysql"
    "gorm.io/gorm"
)

func Test_main(t *testing.T) {
    dsn := "root:pass@tcp(localhost:3306)/dbname?charset=utf8mb4&parseTime=True&loc=Local"
    db, err := gorm.Open(mysql.Open(dsn))
    assert.NoError(t, err)
    assert.NoError(t, db.AutoMigrate(&User{}, &Token{}))

    u := User{
        Name: "user",
        Token: Token{
            Content: "token",
        },
    }
    u1, err := saveUser(db, &u)
    assert.NoError(t, err)
    assert.Equal(t, "token_encrypted", u1.Token.Content)

    u = User{
        ID:   u.ID,
        Name: "user",
        Token: Token{
            Content: "token2",
        },
    }
    u2, err := saveUser(db, &u)
    assert.NoError(t, err)
    assert.Equal(t, "token2_encrypted", u2.Token.Content) // FAIL: actual is token2_encrypted_encrypted
}

func saveUser(db *gorm.DB, u *User) (*User, error) {
    var newUser User
    if err := db.Transaction(func(tx *gorm.DB) error {
        if err := tx.Debug().Session(&gorm.Session{FullSaveAssociations: true}).Save(u).Error; err != nil {
            return err
        }

        if err := tx.Preload("Token").First(&newUser, u.ID).Error; err != nil {
            return err
        }

        return nil
    }); err != nil {
        return nil, err
    }

    return &newUser, nil
}

// - Models

type User struct {
    ID    int    `gorm:"primary_key"`
    Name  string `gorm:"type:varchar(100)"`
    Token Token  `gorm:"foreignKey:UserID"`
}

type Token struct {
    UserID  int    `gorm:"primary_key"`
    Content string `gorm:"type:varchar(100)"`
}

// This method should be called only once
func (t *Token) BeforeSave(tx *gorm.DB) error {
    t.Content += "_encrypted"
    return nil
}

$ go test main_test.go

2023/05/01 11:00:35 /home/ras/misc/go/gorm/main_test.go:42
[2.085ms] [rows:1] INSERT INTO `tokens` (`content`,`user_id`) VALUES ('token_encrypted',7) ON DUPLICATE KEY UPDATE `content`=VALUES(`content`)

2023/05/01 11:00:35 /home/ras/misc/go/gorm/main_test.go:42
[5.084ms] [rows:1] INSERT INTO `users` (`name`) VALUES ('user')

2023/05/01 11:00:35 /home/ras/misc/go/gorm/main_test.go:42
[2.312ms] [rows:2] INSERT INTO `tokens` (`content`,`user_id`) VALUES ('token2_encrypted',7) ON DUPLICATE KEY UPDATE `content`=VALUES(`content`)

2023/05/01 11:00:35 /home/ras/misc/go/gorm/main_test.go:42
[4.827ms] [rows:0] UPDATE `users` SET `name`='user' WHERE `id` = 7

2023/05/01 11:00:35 /home/ras/misc/go/gorm/main_test.go:42
[2.382ms] [rows:2] INSERT INTO `tokens` (`content`,`user_id`) VALUES ('token2_encrypted_encrypted',7) ON DUPLICATE KEY UPDATE `content`=VALUES(`content`)

2023/05/01 11:00:35 /home/ras/misc/go/gorm/main_test.go:42
[5.107ms] [rows:0] INSERT INTO `users` (`name`,`id`) VALUES ('user',7) ON DUPLICATE KEY UPDATE `name`=VALUES(`name`)
--- FAIL: Test_main (0.12s)
    main_test.go:36: 
                Error Trace:    /home/ras/misc/go/gorm/main_test.go:36
                Error:          Not equal: 
                                expected: "token2_encrypted"
                                actual  : "token2_encrypted_encrypted"

                                Diff:
                                --- Expected
                                +++ Actual
                                @@ -1 +1 @@
                                -token2_encrypted
                                +token2_encrypted_encrypted
                Test:           Test_main
FAIL
FAIL    command-line-arguments  0.125s
FAIL

Comment From: github-actions[bot]

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Comment From: GuridMa

Have you solved this? I also encountered the same problem