refactor: added ErrorTransltor interface

error_translator.go

@@ -1,27 +0,0 @@
-package gorm
-
-import "gorm.io/gorm/errtranslator"
-
-func TranslateErr(dialect string, err error) error {
-	var errTranslator errtranslator.ErrTranslator
-
-	switch dialect {
-	case "sqlite":
-		errTranslator = &errtranslator.SqliteErrTranslator{}
-	case "postgres":
-		errTranslator = &errtranslator.PostgresErrTranslator{}
-	case "mysql":
-		errTranslator = &errtranslator.MysqlErrTranslator{}
-	case "mssql":
-		errTranslator = &errtranslator.MssqlErrTranslator{}
-	}
-
-	if errTranslator != nil {
-		translatedErr := errTranslator.Translate(err)
-		if _, ok := translatedErr.(errtranslator.ErrDuplicatedKey); ok {
-			return ErrDuplicatedKey
-		}
-	}
-
-	return err
-}

gorm.go

@@ -347,12 +347,14 @@ func (db *DB) Callback() *callbacks {
 
 // AddError add error to db
 func (db *DB) AddError(err error) error {
-	translatedErr := TranslateErr(db.Dialector.Name(), err)
+	if errTranslator, ok := db.Dialector.(ErrorTranslator); ok {
+		err = errTranslator.Translate(err)
+	}
 
 	if db.Error == nil {
-		db.Error = translatedErr
-	} else if translatedErr != nil {
-		db.Error = fmt.Errorf("%v; %w", db.Error, translatedErr)
+		db.Error = err
+	} else if err != nil {
+		db.Error = fmt.Errorf("%v; %w", db.Error, err)
 	}
 	return db.Error
 }

interfaces.go

@@ -86,3 +86,7 @@ type Rows interface {
 	Err() error
 	Close() error
 }
+
+type ErrorTranslator interface {
+	Translate(err error) error
+}

tests/error_translator_test.go

@@ -5,125 +5,15 @@ import (
 	"testing"
 
 	"gorm.io/gorm"
+	"gorm.io/gorm/utils/tests"
 )
 
-type City struct {
-	gorm.Model
-	Name string `gorm:"unique"`
-}
+func TestDialectorWithErrorTranslatorSupport(t *testing.T) {
+	translatedErr := errors.New("translated error")
+	var db, _ = gorm.Open(tests.DummyDialector{TranslatedErr: translatedErr})
 
-func TestPostgresErrorTranslator(t *testing.T) {
-	if DB.Dialector.Name() != "postgres" {
-		t.Skip()
-	}
-
-	DB.Migrator().DropTable(&City{})
-
-	if err := DB.AutoMigrate(&City{}); err != nil {
-		t.Fatalf("Failed to migrate cities table, got error: %v", err)
-	}
-
-	err := DB.Create(&City{Name: "Amsterdam"}).Error
-	if err != nil {
-		t.Fatalf("errors happened on create: %v", err)
-	}
-
-	// test errors to be translated
-	err = DB.Create(&City{Name: "Amsterdam"}).Error
-	if !errors.Is(err, gorm.ErrDuplicatedKey) {
-		t.Fatalf("expected err: %v got err: %v", gorm.ErrDuplicatedKey, err)
-	}
-
-	// test default errors to not be translated
-	err = DB.Where("name = ?", "Kabul").First(&City{}).Error
-	if err == nil || !errors.Is(err, gorm.ErrRecordNotFound) {
-		t.Fatalf("expected err: %v got err: %v", gorm.ErrRecordNotFound, err)
-	}
-}
-
-func TestMysqlErrorTranslator(t *testing.T) {
-	if DB.Dialector.Name() != "mysql" {
-		t.Skip()
-	}
-
-	DB.Migrator().DropTable(&City{})
-
-	if err := DB.AutoMigrate(&City{}); err != nil {
-		t.Fatalf("Failed to migrate cities table, got error: %v", err)
-	}
-
-	err := DB.Create(&City{Name: "Berlin"}).Error
-	if err != nil {
-		t.Fatalf("errors happened on create: %v", err)
-	}
-
-	// test errors to be translated
-	err = DB.Create(&City{Name: "Berlin"}).Error
-	if !errors.Is(err, gorm.ErrDuplicatedKey) {
-		t.Fatalf("expected err: %v got err: %v", gorm.ErrDuplicatedKey, err)
-	}
-
-	// test default errors to not be translated
-	err = DB.Where("name = ?", "Istanbul").First(&City{}).Error
-	if err == nil || !errors.Is(err, gorm.ErrRecordNotFound) {
-		t.Fatalf("expected err: %v got err: %v", gorm.ErrRecordNotFound, err)
-	}
-}
-
-func TestMssqlErrorTranslator(t *testing.T) {
-	if DB.Dialector.Name() != "mssql" {
-		t.Skip()
-	}
-
-	DB.Migrator().DropTable(&City{})
-
-	if err := DB.AutoMigrate(&City{}); err != nil {
-		t.Fatalf("Failed to migrate cities table, got error: %v", err)
-	}
-
-	err := DB.Create(&City{Name: "Paris"}).Error
-	if err != nil {
-		t.Fatalf("errors happened on create: %v", err)
-	}
-
-	// test errors to be translated
-	err = DB.Create(&City{Name: "Paris"}).Error
-	if !errors.Is(err, gorm.ErrDuplicatedKey) {
-		t.Fatalf("expected err: %v got err: %v", gorm.ErrDuplicatedKey, err)
-	}
-
-	// test default errors to not be translated
-	err = DB.Where("name = ?", "Prague").First(&City{}).Error
-	if err == nil || !errors.Is(err, gorm.ErrRecordNotFound) {
-		t.Fatalf("expected err: %v got err: %v", gorm.ErrRecordNotFound, err)
-	}
-}
-
-func TestSqliteErrorTranslator(t *testing.T) {
-	if DB.Dialector.Name() != "sqlite" {
-		t.Skip()
-	}
-
-	DB.Migrator().DropTable(&City{})
-
-	if err := DB.AutoMigrate(&City{}); err != nil {
-		t.Fatalf("Failed to migrate cities table, got error: %v", err)
-	}
-
-	err := DB.Create(&City{Name: "Madrid"}).Error
-	if err != nil {
-		t.Fatalf("errors happened on create: %v", err)
-	}
-
-	// test errors to be translated
-	err = DB.Create(&City{Name: "Madrid"}).Error
-	if !errors.Is(err, gorm.ErrDuplicatedKey) {
-		t.Fatalf("expected err: %v got err: %v", gorm.ErrDuplicatedKey, err)
-	}
-
-	// test default errors to not be translated
-	err = DB.Where("name = ?", "Rome").First(&City{}).Error
-	if err == nil || !errors.Is(err, gorm.ErrRecordNotFound) {
-		t.Fatalf("expected err: %v got err: %v", gorm.ErrRecordNotFound, err)
+	err := db.AddError(errors.New("some random error"))
+	if !errors.Is(err, translatedErr) {
+		t.Fatalf("expected err: %v got err: %v", translatedErr, err)
 	}
 }

utils/tests/dummy_dialecter.go

@@ -8,7 +8,9 @@ import (
 	"gorm.io/gorm/schema"
 )
 
-type DummyDialector struct{}
+type DummyDialector struct {
+	TranslatedErr error
+}
 
 func (DummyDialector) Name() string {
 	return "dummy"
@@ -92,3 +94,7 @@ func (DummyDialector) Explain(sql string, vars ...interface{}) string {
 func (DummyDialector) DataTypeOf(*schema.Field) string {
 	return ""
 }
+
+func (d DummyDialector) Translate(err error) error {
+	return d.TranslatedErr
+}