Test Preload for BelongsTo/HasOne/HasMany

callbacks/preload.go

@@ -85,27 +85,31 @@ func getIdentityFieldValuesMap(reflectValue reflect.Value, fields []*schema.Fiel
 }
 
 func preloadData(tx *gorm.DB, resultSchema *schema.Schema, foreignKeys []string, foreignValues [][]interface{}) reflect.Value {
-	results := reflect.MakeSlice(reflect.SliceOf(resultSchema.ModelType), 0, 0)
+	slice := reflect.MakeSlice(reflect.SliceOf(resultSchema.ModelType), 0, 0)
+	results := reflect.New(slice.Type())
+	results.Elem().Set(slice)
+
 	queryValues := make([]interface{}, len(foreignValues))
 	if len(foreignKeys) == 1 {
 		for idx, r := range foreignValues {
 			queryValues[idx] = r[0]
 		}
-		tx.Where(clause.IN{Column: foreignKeys[0], Values: queryValues}).Find(results.Addr().Interface())
+		tx.Where(clause.IN{Column: foreignKeys[0], Values: queryValues}).Find(results.Interface())
 	} else {
 		for idx, r := range foreignValues {
 			queryValues[idx] = r
 		}
-		tx.Where(clause.IN{Column: foreignKeys, Values: queryValues}).Find(results.Addr().Interface())
+		tx.Where(clause.IN{Column: foreignKeys, Values: queryValues}).Find(results.Interface())
 	}
 
-	return results
+	return results.Elem()
 }
 
-func preload(tx *gorm.DB, rels []*schema.Relationship, conds []interface{}) {
+func preload(db *gorm.DB, rels []*schema.Relationship, conds []interface{}) {
 	var (
-		reflectValue     = tx.Statement.ReflectValue
+		reflectValue     = db.Statement.ReflectValue
 		rel              = rels[len(rels)-1]
+		tx               = db.Session(&gorm.Session{})
 		relForeignKeys   []string
 		relForeignFields []*schema.Field
 		foreignFields    []*schema.Field
@@ -177,7 +181,7 @@ func preload(tx *gorm.DB, rels []*schema.Relationship, conds []interface{}) {
 
 	fieldValues := make([]reflect.Value, len(foreignFields))
 	for i := 0; i < reflectResults.Len(); i++ {
-		for idx, field := range foreignFields {
+		for idx, field := range relForeignFields {
 			fieldValues[idx] = field.ReflectValueOf(reflectResults.Index(i))
 		}
 
@@ -185,11 +189,13 @@ func preload(tx *gorm.DB, rels []*schema.Relationship, conds []interface{}) {
 			reflectFieldValue := reflect.Indirect(rel.Field.ReflectValueOf(data))
 			switch reflectFieldValue.Kind() {
 			case reflect.Struct:
-				elem := reflectResults.Index(i).Convert(reflectFieldValue.Type().Elem())
+				rel.Field.Set(data, reflectResults.Index(i).Interface())
-				rel.Field.Set(data, elem.Interface())
 			case reflect.Slice, reflect.Array:
-				elem := reflectResults.Index(i).Convert(reflectFieldValue.Type().Elem())
+				if reflectFieldValue.Type().Elem().Kind() == reflect.Ptr {
-				rel.Field.Set(data, reflect.Append(reflectFieldValue, elem).Interface())
+					rel.Field.Set(data, reflect.Append(reflectFieldValue, reflectResults.Index(i).Addr()).Interface())
+				} else {
+					rel.Field.Set(data, reflect.Append(reflectFieldValue, reflectResults.Index(i)).Interface())
+				}
 			}
 		}
 	}

callbacks/query.go

@@ -133,7 +133,7 @@ func Preload(db *gorm.DB) {
 				}
 			}
 
-			preload(db.Session(&gorm.Session{}), rels, db.Statement.Preloads[name])
+			preload(db, rels, db.Statement.Preloads[name])
 		}
 	}
 }

tests/create.go

@@ -56,14 +56,16 @@ func TestCreateAssociations(t *testing.T, db *gorm.DB) {
 }
 
 func TestCreateBelongsToAssociations(t *testing.T, db *gorm.DB) {
-	check := func(t *testing.T, user User) {
+	check := func(t *testing.T, user User, old User) {
-		if user.Company.Name != "" {
+		if old.Company.Name != "" {
 			if user.CompanyID == nil {
 				t.Errorf("Company's foreign key should be saved")
 			} else {
 				var company Company
 				db.First(&company, "id = ?", *user.CompanyID)
-				if company.Name != user.Company.Name {
+				if company.Name != old.Company.Name {
+					t.Errorf("Company's name should be same")
+				} else if user.Company.Name != old.Company.Name {
 					t.Errorf("Company's name should be same")
 				}
 			}
@@ -71,7 +73,7 @@ func TestCreateBelongsToAssociations(t *testing.T, db *gorm.DB) {
 			t.Errorf("Company should not be created for zero value, got: %+v", user.CompanyID)
 		}
 
-		if user.Manager != nil {
+		if old.Manager != nil {
 			if user.ManagerID == nil {
 				t.Errorf("Manager's foreign key should be saved")
 			} else {
@@ -79,6 +81,8 @@ func TestCreateBelongsToAssociations(t *testing.T, db *gorm.DB) {
 				db.First(&manager, "id = ?", *user.ManagerID)
 				if manager.Name != user.Manager.Name {
 					t.Errorf("Manager's name should be same")
+				} else if user.Manager.Name != old.Manager.Name {
+					t.Errorf("Manager's name should be same")
 				}
 			}
 		} else if user.ManagerID != nil {
@@ -99,7 +103,11 @@ func TestCreateBelongsToAssociations(t *testing.T, db *gorm.DB) {
 			t.Fatalf("errors happened when create: %v", err)
 		}
 
-		check(t, user)
+		check(t, user, user)
+
+		var user2 User
+		db.Preload("Company").Preload("Manager").Find(&user2, "id = ?", user.ID)
+		check(t, user2, user)
 	})
 
 	t.Run("BelongsToForBulkInsert", func(t *testing.T) {
@@ -126,8 +134,22 @@ func TestCreateBelongsToAssociations(t *testing.T, db *gorm.DB) {
 			t.Fatalf("errors happened when create: %v", err)
 		}
 
+		var userIDs []uint
 		for _, user := range users {
-			check(t, user)
+			userIDs = append(userIDs, user.ID)
+			check(t, user, user)
+		}
+
+		var users2 []User
+		db.Preload("Company").Preload("Manager").Find(&users2, "id IN (?)", userIDs)
+		for idx, user := range users2 {
+			check(t, user, users[idx])
+		}
+
+		var users3 []User
+		db.Preload("Company").Preload("Manager").Find(users3, "id IN (?)", userIDs)
+		for idx, user := range users3 {
+			check(t, user, users[idx])
 		}
 	})
 
@@ -156,7 +178,7 @@ func TestCreateBelongsToAssociations(t *testing.T, db *gorm.DB) {
 		}
 
 		for _, user := range users {
-			check(t, *user)
+			check(t, *user, *user)
 		}
 	})
 
@@ -185,13 +207,13 @@ func TestCreateBelongsToAssociations(t *testing.T, db *gorm.DB) {
 		}
 
 		for _, user := range users {
-			check(t, *user)
+			check(t, *user, *user)
 		}
 	})
 }
 
 func TestCreateHasOneAssociations(t *testing.T, db *gorm.DB) {
-	check := func(t *testing.T, user User) {
+	check := func(t *testing.T, user User, old User) {
 		if user.Account.ID == 0 {
 			t.Errorf("Account should be saved")
 		} else if user.Account.UserID.Int64 != int64(user.ID) {
@@ -200,7 +222,9 @@ func TestCreateHasOneAssociations(t *testing.T, db *gorm.DB) {
 			var account Account
 			db.First(&account, "id = ?", user.Account.ID)
 			if account.Number != user.Account.Number {
-				t.Errorf("Account's number should be sme")
+				t.Errorf("Account's number should be same")
+			} else if user.Account.Number != old.Account.Number {
+				t.Errorf("Account's number should be same")
 			}
 		}
 	}
@@ -217,7 +241,11 @@ func TestCreateHasOneAssociations(t *testing.T, db *gorm.DB) {
 			t.Fatalf("errors happened when create: %v", err)
 		}
 
-		check(t, user)
+		check(t, user, user)
+
+		var user2 User
+		db.Preload("Account").Find(&user2, "id = ?", user.ID)
+		check(t, user2, user)
 	})
 
 	t.Run("HasOneForBulkInsert", func(t *testing.T) {
@@ -242,8 +270,16 @@ func TestCreateHasOneAssociations(t *testing.T, db *gorm.DB) {
 			t.Fatalf("errors happened when create: %v", err)
 		}
 
+		var userIDs []uint
 		for _, user := range users {
-			check(t, user)
+			userIDs = append(userIDs, user.ID)
+			check(t, user, user)
+		}
+
+		var users2 []User
+		db.Preload("Account").Find(&users2, "id IN (?)", userIDs)
+		for idx, user := range users2 {
+			check(t, user, users[idx])
 		}
 	})
 
@@ -270,7 +306,7 @@ func TestCreateHasOneAssociations(t *testing.T, db *gorm.DB) {
 		}
 
 		for _, user := range users {
-			check(t, *user)
+			check(t, *user, *user)
 		}
 	})
 
@@ -297,11 +333,11 @@ func TestCreateHasOneAssociations(t *testing.T, db *gorm.DB) {
 		}
 
 		for _, user := range users {
-			check(t, user)
+			check(t, user, user)
 		}
 	})
 
-	checkPet := func(t *testing.T, pet Pet) {
+	checkPet := func(t *testing.T, pet Pet, old Pet) {
 		if pet.Toy.OwnerID != fmt.Sprint(pet.ID) || pet.Toy.OwnerType != "pets" {
 			t.Errorf("Failed to create polymorphic has one association - toy owner id %v, owner type %v", pet.Toy.OwnerID, pet.Toy.OwnerType)
 		} else {
@@ -309,6 +345,8 @@ func TestCreateHasOneAssociations(t *testing.T, db *gorm.DB) {
 			db.First(&toy, "owner_id = ? and owner_type = ?", pet.Toy.OwnerID, pet.Toy.OwnerType)
 			if toy.Name != pet.Toy.Name {
 				t.Errorf("Failed to query saved polymorphic has one association")
+			} else if old.Toy.Name != pet.Toy.Name {
+				t.Errorf("Failed to query saved polymorphic has one association")
 			}
 		}
 	}
@@ -323,7 +361,11 @@ func TestCreateHasOneAssociations(t *testing.T, db *gorm.DB) {
 			t.Fatalf("errors happened when create: %v", err)
 		}
 
-		checkPet(t, pet)
+		checkPet(t, pet, pet)
+
+		var pet2 Pet
+		db.Preload("Toy").Find(&pet2, "id = ?", pet.ID)
+		checkPet(t, pet2, pet)
 	})
 
 	t.Run("PolymorphicHasOneForBulkInsert", func(t *testing.T) {
@@ -342,8 +384,16 @@ func TestCreateHasOneAssociations(t *testing.T, db *gorm.DB) {
 			t.Fatalf("errors happened when create: %v", err)
 		}
 
+		var petIDs []uint
 		for _, pet := range pets {
-			checkPet(t, pet)
+			petIDs = append(petIDs, pet.ID)
+			checkPet(t, pet, pet)
+		}
+
+		var pets2 []Pet
+		db.Preload("Toy").Find(&pets2, "id IN (?)", petIDs)
+		for idx, pet := range pets2 {
+			checkPet(t, pet, pets[idx])
 		}
 	})
 
@@ -364,7 +414,7 @@ func TestCreateHasOneAssociations(t *testing.T, db *gorm.DB) {
 		}
 
 		for _, pet := range pets {
-			checkPet(t, *pet)
+			checkPet(t, *pet, *pet)
 		}
 	})
 
@@ -385,14 +435,14 @@ func TestCreateHasOneAssociations(t *testing.T, db *gorm.DB) {
 		}
 
 		for _, pet := range pets {
-			checkPet(t, *pet)
+			checkPet(t, *pet, *pet)
 		}
 	})
 }
 
 func TestCreateHasManyAssociations(t *testing.T, db *gorm.DB) {
-	check := func(t *testing.T, user User) {
+	check := func(t *testing.T, user User, old User) {
-		for _, pet := range user.Pets {
+		for idx, pet := range user.Pets {
 			if pet.ID == 0 {
 				t.Errorf("Pet's foreign key should be saved")
 			}
@@ -403,6 +453,8 @@ func TestCreateHasManyAssociations(t *testing.T, db *gorm.DB) {
 				t.Errorf("Pet's name should be same")
 			} else if result.UserID != user.ID {
 				t.Errorf("Pet's foreign key should be saved")
+			} else if result.Name != old.Pets[idx].Name {
+				t.Errorf("Pet's name should be same")
 			}
 		}
 	}
@@ -419,7 +471,11 @@ func TestCreateHasManyAssociations(t *testing.T, db *gorm.DB) {
 			t.Fatalf("errors happened when create: %v", err)
 		}
 
-		check(t, user)
+		check(t, user, user)
+
+		var user2 User
+		db.Preload("Pets").Find(&user2, "id = ?", user.ID)
+		check(t, user2, user)
 	})
 
 	t.Run("HasManyForBulkInsert", func(t *testing.T) {
@@ -444,8 +500,16 @@ func TestCreateHasManyAssociations(t *testing.T, db *gorm.DB) {
 			t.Fatalf("errors happened when create: %v", err)
 		}
 
+		var userIDs []uint
 		for _, user := range users {
-			check(t, user)
+			userIDs = append(userIDs, user.ID)
+			check(t, user, user)
+		}
+
+		var users2 []User
+		db.Preload("Pets").Find(&users2, "id IN (?)", userIDs)
+		for idx, user := range users2 {
+			check(t, user, users[idx])
 		}
 	})
 
@@ -472,7 +536,7 @@ func TestCreateHasManyAssociations(t *testing.T, db *gorm.DB) {
 		}
 
 		for _, user := range users {
-			check(t, *user)
+			check(t, *user, *user)
 		}
 	})
 
@@ -499,11 +563,11 @@ func TestCreateHasManyAssociations(t *testing.T, db *gorm.DB) {
 		}
 
 		for _, user := range users {
-			check(t, *user)
+			check(t, *user, *user)
 		}
 	})
 
-	checkToy := func(t *testing.T, user User) {
+	checkToy := func(t *testing.T, user User, old User) {
 		for idx, toy := range user.Toys {
 			if toy.ID == 0 {
 				t.Fatalf("Failed to create toy #%v", idx)
@@ -513,6 +577,8 @@ func TestCreateHasManyAssociations(t *testing.T, db *gorm.DB) {
 			db.First(&result, "id = ?", toy.ID)
 			if result.Name != toy.Name {
 				t.Errorf("Failed to query saved toy")
+			} else if result.Name != old.Toys[idx].Name {
+				t.Errorf("Failed to query saved toy")
 			} else if result.OwnerID != fmt.Sprint(user.ID) || result.OwnerType != "users" {
 				t.Errorf("Failed to save relation")
 			}
@@ -531,7 +597,11 @@ func TestCreateHasManyAssociations(t *testing.T, db *gorm.DB) {
 			t.Fatalf("errors happened when create: %v", err)
 		}
 
-		checkToy(t, user)
+		checkToy(t, user, user)
+
+		var user2 User
+		db.Preload("Toys").Find(&user2, "id = ?", user.ID)
+		check(t, user2, user)
 	})
 
 	t.Run("PolymorphicHasManyForBulkInsert", func(t *testing.T) {
@@ -556,8 +626,16 @@ func TestCreateHasManyAssociations(t *testing.T, db *gorm.DB) {
 			t.Fatalf("errors happened when create: %v", err)
 		}
 
+		var userIDs []uint
 		for _, user := range users {
-			checkToy(t, user)
+			userIDs = append(userIDs, user.ID)
+			checkToy(t, user, user)
+		}
+
+		var users2 []User
+		db.Preload("Toys").Find(&users2, "id IN (?)", userIDs)
+		for idx, user := range users2 {
+			check(t, user, users[idx])
 		}
 	})
 
@@ -584,7 +662,7 @@ func TestCreateHasManyAssociations(t *testing.T, db *gorm.DB) {
 		}
 
 		for _, user := range users {
-			checkToy(t, *user)
+			checkToy(t, *user, *user)
 		}
 	})
 
@@ -611,7 +689,7 @@ func TestCreateHasManyAssociations(t *testing.T, db *gorm.DB) {
 		}
 
 		for _, user := range users {
-			checkToy(t, user)
+			checkToy(t, user, user)
 		}
 	})
 }

utils/utils.go

@@ -1,6 +1,7 @@
 package utils
 
 import (
+	"database/sql/driver"
 	"fmt"
 	"reflect"
 	"regexp"
@@ -45,6 +46,9 @@ func ToStringKey(values ...reflect.Value) string {
 
 	for idx, value := range values {
 		rv := reflect.Indirect(value).Interface()
+		if valuer, ok := rv.(driver.Valuer); ok {
+			rv, _ = valuer.Value()
+		}
 
 		switch v := rv.(type) {
 		case string: