test for nested generic version Join/Preload

callbacks/query.go

@@ -110,7 +110,7 @@ func BuildQuerySQL(db *gorm.DB) {
 				}
 			}
 
-			specifiedRelationsName := make(map[string]interface{})
+			specifiedRelationsName := map[string]string{clause.CurrentTable: clause.CurrentTable}
 			for _, join := range db.Statement.Joins {
 				if db.Statement.Schema != nil {
 					var isRelations bool // is relations or raw sql
@@ -124,12 +124,12 @@ func BuildQuerySQL(db *gorm.DB) {
 						nestedJoinNames := strings.Split(join.Name, ".")
 						if len(nestedJoinNames) > 1 {
 							isNestedJoin := true
-							gussNestedRelations := make([]*schema.Relationship, 0, len(nestedJoinNames))
+							guessNestedRelations := make([]*schema.Relationship, 0, len(nestedJoinNames))
 							currentRelations := db.Statement.Schema.Relationships.Relations
 							for _, relname := range nestedJoinNames {
 								// incomplete match, only treated as raw sql
 								if relation, ok = currentRelations[relname]; ok {
-									gussNestedRelations = append(gussNestedRelations, relation)
+									guessNestedRelations = append(guessNestedRelations, relation)
 									currentRelations = relation.FieldSchema.Relationships.Relations
 								} else {
 									isNestedJoin = false
@@ -139,22 +139,13 @@ func BuildQuerySQL(db *gorm.DB) {
 
 							if isNestedJoin {
 								isRelations = true
-								relations = gussNestedRelations
+								relations = guessNestedRelations
 							}
 						}
 					}
 
 					if isRelations {
-						genJoinClause := func(joinType clause.JoinType, parentTableName string, relation *schema.Relationship) clause.Join {
-							tableAliasName := join.Alias
-
-							if tableAliasName == "" {
-								tableAliasName = relation.Name
-								if parentTableName != clause.CurrentTable {
-									tableAliasName = utils.NestedRelationName(parentTableName, tableAliasName)
-								}
-							}
-
+						genJoinClause := func(joinType clause.JoinType, tableAliasName string, parentTableName string, relation *schema.Relationship) clause.Join {
 							columnStmt := gorm.Statement{
 								Table: tableAliasName, DB: db, Schema: relation.FieldSchema,
 								Selects: join.Selects, Omits: join.Omits,
@@ -237,19 +228,24 @@ func BuildQuerySQL(db *gorm.DB) {
 						}
 
 						parentTableName := clause.CurrentTable
-						for _, rel := range relations {
+						for idx, rel := range relations {
 							// joins table alias like "Manager, Company, Manager__Company"
-							nestedAlias := utils.NestedRelationName(parentTableName, rel.Name)
-							if _, ok := specifiedRelationsName[nestedAlias]; !ok {
-								fromClause.Joins = append(fromClause.Joins, genJoinClause(join.JoinType, parentTableName, rel))
-								specifiedRelationsName[nestedAlias] = nil
+							curAliasName := rel.Name
+							if parentTableName != clause.CurrentTable {
+								curAliasName = utils.NestedRelationName(parentTableName, curAliasName)
 							}
 
-							if parentTableName != clause.CurrentTable {
-								parentTableName = utils.NestedRelationName(parentTableName, rel.Name)
-							} else {
-								parentTableName = rel.Name
+							if _, ok := specifiedRelationsName[curAliasName]; !ok {
+								aliasName := curAliasName
+								if idx == len(relations)-1 && join.Alias != "" {
+									aliasName = join.Alias
+								}
+
+								fromClause.Joins = append(fromClause.Joins, genJoinClause(join.JoinType, aliasName, specifiedRelationsName[parentTableName], rel))
+								specifiedRelationsName[curAliasName] = aliasName
 							}
+
+							parentTableName = curAliasName
 						}
 					} else {
 						fromClause.Joins = append(fromClause.Joins, clause.Join{

generics.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"database/sql"
 	"fmt"
+	"sort"
 	"strings"
 
 	"gorm.io/gorm/clause"
@@ -341,6 +342,9 @@ func (c chainG[T]) Joins(jt clause.JoinTarget, on func(db JoinBuilder, joinTable
 		}
 
 		db.Statement.Joins = append(db.Statement.Joins, j)
+		sort.Slice(db.Statement.Joins, func(i, j int) bool {
+			return db.Statement.Joins[i].Name < db.Statement.Joins[j].Name
+		})
 		return db
 	})
 }
@@ -399,7 +403,22 @@ func (c chainG[T]) Preload(association string, query func(db PreloadBuilder) err
 
 			relation, ok := db.Statement.Schema.Relationships.Relations[association]
 			if !ok {
-				db.AddError(fmt.Errorf("relation %s not found", association))
+				if preloadFields := strings.Split(association, "."); len(preloadFields) > 1 {
+					relationships := db.Statement.Schema.Relationships
+					for _, field := range preloadFields {
+						var ok bool
+						relation, ok = relationships.Relations[field]
+						if ok {
+							relationships = relation.FieldSchema.Relationships
+						} else {
+							db.AddError(fmt.Errorf("relation %s not found", association))
+							return nil
+						}
+					}
+				} else {
+					db.AddError(fmt.Errorf("relation %s not found", association))
+					return nil
+				}
 			}
 
 			if q.limitPerRecord > 0 {

scan.go

@@ -245,9 +245,11 @@ func Scan(rows Rows, db *DB, mode ScanMode) {
 							matchedFieldCount[column] = 1
 						}
 					} else if names := utils.SplitNestedRelationName(column); len(names) > 1 { // has nested relation
+						aliasName := utils.JoinNestedRelationNames(names[0 : len(names)-1])
 						for _, join := range db.Statement.Joins {
-							if join.Alias == names[0] {
+							if join.Alias == aliasName {
 								names = append(strings.Split(join.Name, "."), names[len(names)-1])
+								break
 							}
 						}
 

tests/generics_test.go

@@ -6,6 +6,7 @@ import (
 	"fmt"
 	"reflect"
 	"sort"
+	"strconv"
 	"strings"
 	"testing"
 
@@ -378,6 +379,82 @@ func TestGenericsJoins(t *testing.T) {
 	}
 }
 
+func TestGenericsNestedJoins(t *testing.T) {
+	users := []User{
+		{
+			Name: "generics-nested-joins-1",
+			Manager: &User{
+				Name: "generics-nested-joins-manager-1",
+				Company: Company{
+					Name: "generics-nested-joins-manager-company-1",
+				},
+				NamedPet: &Pet{
+					Name: "generics-nested-joins-manager-namepet-1",
+					Toy: Toy{
+						Name: "generics-nested-joins-manager-namepet-toy-1",
+					},
+				},
+			},
+			NamedPet: &Pet{Name: "generics-nested-joins-namepet-1", Toy: Toy{Name: "generics-nested-joins-namepet-toy-1"}},
+		},
+		{
+			Name:     "generics-nested-joins-2",
+			Manager:  GetUser("generics-nested-joins-manager-2", Config{Company: true, NamedPet: true}),
+			NamedPet: &Pet{Name: "generics-nested-joins-namepet-2", Toy: Toy{Name: "generics-nested-joins-namepet-toy-2"}},
+		},
+	}
+
+	ctx := context.Background()
+	db := gorm.G[User](DB)
+	db.CreateInBatches(ctx, &users, 100)
+
+	var userIDs []uint
+	for _, user := range users {
+		userIDs = append(userIDs, user.ID)
+	}
+
+	users2, err := db.Joins(clause.LeftJoin.Association("Manager"), nil).
+		Joins(clause.LeftJoin.Association("Manager.Company"), nil).
+		Joins(clause.LeftJoin.Association("Manager.NamedPet.Toy"), nil).
+		Joins(clause.LeftJoin.Association("NamedPet.Toy"), nil).
+		Joins(clause.LeftJoin.Association("NamedPet").As("t"), nil).
+		Where(map[string]any{"id": userIDs}).Find(ctx)
+
+	if err != nil {
+		t.Fatalf("Failed to load with joins, got error: %v", err)
+	} else if len(users2) != len(users) {
+		t.Fatalf("Failed to load join users, got: %v, expect: %v", len(users2), len(users))
+	}
+
+	sort.Slice(users2, func(i, j int) bool {
+		return users2[i].ID > users2[j].ID
+	})
+
+	sort.Slice(users, func(i, j int) bool {
+		return users[i].ID > users[j].ID
+	})
+
+	for idx, user := range users {
+		// user
+		CheckUser(t, user, users2[idx])
+		if users2[idx].Manager == nil {
+			t.Fatalf("Failed to load Manager")
+		}
+		// manager
+		CheckUser(t, *user.Manager, *users2[idx].Manager)
+		// user pet
+		if users2[idx].NamedPet == nil {
+			t.Fatalf("Failed to load NamedPet")
+		}
+		CheckPet(t, *user.NamedPet, *users2[idx].NamedPet)
+		// manager pet
+		if users2[idx].Manager.NamedPet == nil {
+			t.Fatalf("Failed to load NamedPet")
+		}
+		CheckPet(t, *user.Manager.NamedPet, *users2[idx].Manager.NamedPet)
+	}
+}
+
 func TestGenericsPreloads(t *testing.T) {
 	ctx := context.Background()
 	db := gorm.G[User](DB)
@@ -499,6 +576,35 @@ func TestGenericsPreloads(t *testing.T) {
 	}
 }
 
+func TestGenericsNestedPreloads(t *testing.T) {
+	user := *GetUser("generics_nested_preload", Config{Pets: 2})
+	user.Friends = []*User{GetUser("generics_nested_preload", Config{Pets: 5})}
+
+	ctx := context.Background()
+	db := gorm.G[User](DB)
+
+	for idx, pet := range user.Pets {
+		pet.Toy = Toy{Name: "toy_nested_preload_" + strconv.Itoa(idx+1)}
+	}
+
+	if err := db.Create(ctx, &user); err != nil {
+		t.Fatalf("errors happened when create: %v", err)
+	}
+
+	user2, err := db.Preload("Pets.Toy", nil).Preload("Friends.Pets", func(db gorm.PreloadBuilder) error {
+		db.LimitPerRecord(3)
+		return nil
+	}).Where(user.ID).Take(ctx)
+	if err != nil {
+		t.Errorf("failed to nested preload user")
+	}
+	CheckUser(t, user2, user)
+
+	if len(user2.Friends) != 1 || len(user2.Friends[0].Pets) != 3 {
+		t.Errorf("failed to nested preload with limit per record")
+	}
+}
+
 func TestGenericsDistinct(t *testing.T) {
 	ctx := context.Background()
 
@@ -586,3 +692,40 @@ func TestGenericsSubQuery(t *testing.T) {
 		t.Errorf("Three users should be found, instead found %d", len(results))
 	}
 }
+
+func TestGenericsUpsert(t *testing.T) {
+	ctx := context.Background()
+	lang := Language{Code: "upsert", Name: "Upsert"}
+
+	if err := gorm.G[Language](DB, clause.OnConflict{DoNothing: true}).Create(ctx, &lang); err != nil {
+		t.Fatalf("failed to upsert, got %v", err)
+	}
+
+	lang2 := Language{Code: "upsert", Name: "Upsert"}
+	if err := gorm.G[Language](DB, clause.OnConflict{DoNothing: true}).Create(ctx, &lang2); err != nil {
+		t.Fatalf("failed to upsert, got %v", err)
+	}
+
+	langs, err := gorm.G[Language](DB).Where("code = ?", lang.Code).Find(ctx)
+	if err != nil {
+		t.Errorf("no error should happen when find languages with code, but got %v", err)
+	} else if len(langs) != 1 {
+		t.Errorf("should only find only 1 languages, but got %+v", langs)
+	}
+
+	lang3 := Language{Code: "upsert", Name: "Upsert"}
+	if err := gorm.G[Language](DB, clause.OnConflict{
+		Columns:   []clause.Column{{Name: "code"}},
+		DoUpdates: clause.Assignments(map[string]interface{}{"name": "upsert-new"}),
+	}).Create(ctx, &lang3); err != nil {
+		t.Fatalf("failed to upsert, got %v", err)
+	}
+
+	if langs, err := gorm.G[Language](DB).Where("code = ?", lang.Code).Find(ctx); err != nil {
+		t.Errorf("no error should happen when find languages with code, but got %v", err)
+	} else if len(langs) != 1 {
+		t.Errorf("should only find only 1 languages, but got %+v", langs)
+	} else if langs[0].Name != "upsert-new" {
+		t.Errorf("should update name on conflict, but got name %+v", langs[0].Name)
+	}
+}