fix: replace associations with custom pk

callbacks/associations.go

@@ -178,7 +178,8 @@ func SaveAfterAssociations(create bool) func(db *gorm.DB) {
 							} else if ref.PrimaryValue != "" {
 								db.AddError(ref.ForeignKey.Set(db.Statement.Context, f, ref.PrimaryValue))
 							}
-							assignmentColumns = append(assignmentColumns, ref.ForeignKey.DBName)
+
+							assignmentColumns = append(assignmentColumns, getAssignmentColumnsForForeignKey(ref.ForeignKey)...)
 						}
 
 						saveAssociations(db, rel, f, selectColumns, restricted, assignmentColumns)
@@ -431,6 +432,33 @@ func saveAssociations(db *gorm.DB, rel *schema.Relationship, rValues reflect.Val
 	return db.AddError(tx.Create(values).Error)
 }
 
+func getAssignmentColumnsForForeignKey(foreignKey *schema.Field) []string {
+	var assignmentColumns []string
+
+	if foreignKey.Schema == nil {
+		return assignmentColumns
+	}
+
+	if !foreignKey.PrimaryKey {
+		assignmentColumns = append(assignmentColumns, foreignKey.DBName)
+		return assignmentColumns
+	}
+
+	for _, field := range foreignKey.Schema.Fields {
+		if field.PrimaryKey {
+			continue
+		}
+
+		if field.DBName == "" {
+			continue
+		}
+
+		assignmentColumns = append(assignmentColumns, field.DBName)
+	}
+
+	return assignmentColumns
+}
+
 // check association values has been saved
 // if values kind is Struct, check it has been saved
 // if values kind is Slice/Array, check all items have been saved

tests/associations_has_one_test.go

@@ -256,14 +256,44 @@ func TestPolymorphicHasOneAssociationForSlice(t *testing.T) {
 	AssertAssociationCount(t, pets, "Toy", 0, "After Clear")
 }
 
-func TestHasOneAssociationReplaceWithNonValidValue(t *testing.T) {
-	user := User{Name: "jinzhu", Account: Account{Number: "1"}}
+func TestReplaceHasOneAssociationWithCustomPK(t *testing.T) {
+	if DB.Dialector.Name() == "sqlite" {
+		return
+	}
 
-	if err := DB.Create(&user).Error; err != nil {
+	DB.Migrator().DropTable(&Owner{})
+	DB.Migrator().DropTable(&CreditCard{})
+
+	DB.AutoMigrate(&CreditCard{})
+	DB.AutoMigrate(&Owner{})
+
+	owner := Owner{
+		Name: "jinzhu",
+		CreditCard: CreditCard{
+			Number:   "123",
+			UserName: "jinzhu",
+		},
+	}
+
+	if err := DB.Create(&owner).Error; err != nil {
 		t.Fatalf("errors happened when create: %v", err)
 	}
 
-	if err := DB.Model(&user).Association("Languages").Replace(Account{Number: "2"}); err == nil {
-		t.Error("expected association error to be not nil")
+	wantNumber := "456"
+
+	if err := DB.Model(&owner).Association("CreditCard").Replace(&CreditCard{
+		Number:   wantNumber,
+		UserName: "jinzhu",
+	}); err != nil {
+		t.Fatalf("errors happened when create: %v", err)
+	}
+
+	var result Owner
+	if err := DB.Preload("CreditCard").First(&result, owner.ID).Error; err != nil {
+		t.Fatalf("errors happened when getting credit card: %v", err)
+	}
+
+	if result.CreditCard.Number != wantNumber {
+		t.Fatal("wrong credit card number")
 	}
 }

utils/tests/models.go

@@ -102,3 +102,14 @@ type Child struct {
 	ParentID *uint
 	Parent   *Parent
 }
+
+type Owner struct {
+	gorm.Model
+	Name       string     `gorm:"index"`
+	CreditCard CreditCard `gorm:"foreignKey:OwnerName;references:name"`
+}
+
+type CreditCard struct {
+	Number   string
+	UserName string `gorm:"primaryKey;unique;size:255"`
+}