自定义实现的 driver.Valuer 的 Value 方法，会被调用 3 次

db.go

@@ -83,7 +83,7 @@ func OpenTestConnection() (db *gorm.DB, err error) {
 
 func RunMigrations() {
 	var err error
-	allModels := []interface{}{&User{}, &Account{}, &Pet{}, &Company{}, &Toy{}, &Language{}}
+	allModels := []interface{}{&Model{}}
 	rand.Seed(time.Now().UnixNano())
 	rand.Shuffle(len(allModels), func(i, j int) { allModels[i], allModels[j] = allModels[j], allModels[i] })
 

main_test.go

@@ -1,20 +1,104 @@
 package main
 
 import (
+	"context"
+	"slices"
 	"testing"
 )
 
 // GORM_REPO: https://github.com/go-gorm/gorm.git
 // GORM_BRANCH: master
 // TEST_DRIVERS: sqlite, mysql, postgres, sqlserver
-
 func TestGORM(t *testing.T) {
-	user := User{Name: "jinzhu"}
-
-	DB.Create(&user)
+	arrayInput := []string{"A", "B", "C"}
+	arraySave := []string{"A1", "B1", "C1"}
 
-	var result User
-	if err := DB.First(&result, user.ID).Error; err != nil {
-		t.Errorf("Failed, got error: %v", err)
+	data := Model{
+		JsonField: JsonField{
+			Array: slices.Clone(arrayInput),
+		},
 	}
+
+	t.Run("Create", func(t *testing.T) {
+		err := DB.WithContext(context.TODO()).Model(&Model{}).
+			Create(&data).
+			Error
+		if err != nil {
+			t.Errorf("Failed, create error: %v", err)
+		}
+
+		arrayCreate := data.JsonField.Array
+		t.Logf("arrayCreate is %v", arrayCreate)
+		if !slices.Equal(arrayCreate, arrayInput) {
+			t.Errorf("Failed, json field arrayCreate %v not equal arrayInput %v", arrayCreate, arrayInput)
+		}
+	})
+
+	t.Run("Find With SkipCustomMethod", func(t *testing.T) {
+		var modelSkip *ModelSkip
+		err := DB.WithContext(context.TODO()).Model(&Model{}).
+			Where("id", data.ID).
+			Find(&modelSkip).
+			Error
+		if err != nil {
+			t.Errorf("Failed, get error: %v", err)
+		}
+
+		arraySkip := modelSkip.JsonField.Array
+		t.Logf("arraySkip is %v", arraySkip)
+		if !slices.Equal(arraySkip, arraySave) {
+			t.Errorf("Failed, modelSkip field arraySkip %v not equal arraySave %v", arraySkip, arraySave)
+		}
+	})
+
+	t.Run("Find", func(t *testing.T) {
+		var row *Model
+		err := DB.WithContext(context.TODO()).Model(&Model{}).
+			Where("id", data.ID).
+			Find(&row).
+			Error
+		if err != nil {
+			t.Errorf("Failed, find error: %v", err)
+		}
+
+		arrayFind := row.JsonField.Array
+		t.Logf("arrayFind is %v", arrayFind)
+		if !slices.Equal(arrayFind, arrayInput) {
+			t.Errorf("Failed, json field arrayFind %v not equal arrayInput %v", arrayFind, arrayInput)
+		}
+	})
+
+	t.Run("Update", func(t *testing.T) {
+		arrayUpdate := []string{"X", "Y", "Z"}
+		arrayUpdateSave := []string{"X1", "Y1", "Z1"}
+
+		err := DB.WithContext(context.TODO()).Model(&Model{}).
+			Where("id", data.ID).
+			Updates(Model{
+				JsonField: JsonField{
+					Array: slices.Clone(arrayUpdate),
+				},
+			}).
+			Error
+		if err != nil {
+			t.Errorf("Failed, update error: %v", err)
+		}
+
+		t.Run("ModelSkip", func(t *testing.T) {
+			var modelSkip *ModelSkip
+			err = DB.WithContext(context.TODO()).Model(&Model{}).
+				Where("id", data.ID).
+				Find(&modelSkip).Error
+			if err != nil {
+				t.Errorf("Failed, get error: %v", err)
+			}
+
+			arraySkip := modelSkip.JsonField.Array
+			t.Logf("arraySkip is %v", arraySkip)
+			if !slices.Equal(arraySkip, arrayUpdateSave) {
+				t.Errorf("Failed, json field %v arrayInput not equal arrayUpdateSave %v", arraySkip, arrayUpdateSave)
+			}
+		})
+	})
+
 }

models.go

@@ -1,60 +1,66 @@
 package main
 
 import (
-	"database/sql"
-	"time"
+	"database/sql/driver"
+	"encoding/json"
+	"fmt"
+	"slices"
+	"strings"
 
 	"gorm.io/gorm"
 )
 
-// User has one `Account` (has one), many `Pets` (has many) and `Toys` (has many - polymorphic)
-// He works in a Company (belongs to), he has a Manager (belongs to - single-table), and also managed a Team (has many - single-table)
-// He speaks many languages (many to many) and has many friends (many to many - single-table)
-// His pet also has one Toy (has one - polymorphic)
-type User struct {
+type Model struct {
 	gorm.Model
-	Name      string
-	Age       uint
-	Birthday  *time.Time
-	Account   Account
-	Pets      []*Pet
-	Toys      []Toy `gorm:"polymorphic:Owner"`
-	CompanyID *int
-	Company   Company
-	ManagerID *uint
-	Manager   *User
-	Team      []User     `gorm:"foreignkey:ManagerID"`
-	Languages []Language `gorm:"many2many:UserSpeak"`
-	Friends   []*User    `gorm:"many2many:user_friends"`
-	Active    bool
-}
-
-type Account struct {
-	gorm.Model
-	UserID sql.NullInt64
-	Number string
+	JsonField JsonField `gorm:"type:json;not null;" json:"jsonField"`
 }
 
-type Pet struct {
-	gorm.Model
-	UserID *uint
-	Name   string
-	Toy    Toy `gorm:"polymorphic:Owner;"`
+type JsonField struct {
+	Array []string `json:"array"`
 }
 
-type Toy struct {
-	gorm.Model
-	Name      string
-	OwnerID   string
-	OwnerType string
+func (j *JsonField) Scan(src any) error {
+	err := json.Unmarshal(src.([]byte), &j)
+	if err != nil {
+		return fmt.Errorf("json scan fail, err: %w", err)
+	}
+
+	for i, s := range j.Array {
+		j.Array[i], _ = strings.CutSuffix(s, "1")
+	}
+
+	return nil
+}
+
+func (j JsonField) Value() (driver.Value, error) {
+	clone := slices.Clone(j.Array)
+	for i := range clone {
+		clone[i] += "1" // 我想要修改（加密）原来的字段，I want to modify/encrypt the fields
+	}
+
+	data, err := json.Marshal(JsonField{
+		Array: clone,
+	})
+	if err != nil {
+		return nil, fmt.Errorf("json marshal fail, err: %w", err)
+	}
+
+	return data, nil
+}
+
+type SkipCustomMethod struct {
+	Array []string `gorm:"type:json;not null;" json:"array"`
+}
+
+func (s *SkipCustomMethod) Scan(src any) error {
+	return json.Unmarshal(src.([]byte), &s)
 }
 
-type Company struct {
-	ID   int
-	Name string
+func (s SkipCustomMethod) Value() (driver.Value, error) {
+	return json.Marshal(s)
 }
 
-type Language struct {
-	Code string `gorm:"primarykey"`
-	Name string
+// ModelSkip to skip JsonField.Value and JsonField.Scan
+type ModelSkip struct {
+	JsonField SkipCustomMethod `json:"jsonField"`
 }