fix(scan): 修复对struct存在重复属性导致的崩溃

新增了在递归scan对象属性的时候发现嵌套属性名称和当前属性名称一致的时候做了友好错误提示

README.md

@@ -73,6 +73,7 @@ INSERT INTO
 ### 查询映射 -- 示例
 
 ```go
+// 如果没有结果，会返回 sql.ErrNoRows
 func QueryOne(db *sql.DB) (*User,error){
     tdMapper := NewMapper()
 
@@ -89,8 +90,7 @@ func QueryOne(db *sql.DB) (*User,error){
     return &user, nil
 }
 
-// 如果查询结果数量为0，则返回 sql.ErrNoRows
-// var ErrNoRows = errors.New("sql: no rows in result set")
+// 如果查询结果数量为0，不会返回错误
 func QueryAll(db *sql.DB)([]*User, error) {
     tdMapper := NewMapper()
     

mapping.go

@@ -65,7 +65,7 @@ func (b *Mapper) extractStructData(data ...any) (map[string][]*TableRowMateria,
 			}
 
 			if tableName == "" {
-				return nil, fmt.Errorf("not import TableName() string func for struct type: %s", uniqueTypeName)
+				return nil, fmt.Errorf("not func TableName() string func for struct type: %s", uniqueTypeName)
 			}
 		}
 
@@ -247,10 +247,6 @@ func (b *Mapper) ScanRowsWithContext(ctx context.Context, target any, rows *sql.
 			// 将新实例添加到slice中
 			vf.Set(reflect.Append(vf, newStruct))
 		}
-
-		if vf.Len() == 0 { // 如果slice为空，返回 sql.ErrNoRows
-			return sql.ErrNoRows
-		}
 		return nil
 	default:
 		return errors.New("target must be a pointer to a struct or a slice of structs")
@@ -277,11 +273,11 @@ func (b *Mapper) scanRow(target reflect.Value, rows *sql.Rows) error {
 	dest := make([]interface{}, len(columns))
 	for i, colName := range columns {
 		// 拿到缓存的字段索引
-		if idx, ok := mate.DBName2IndexCache[colName]; ok {
-			dest[i] = target.FieldByIndex(idx).Addr().Interface()
-		} else {
+		idx, ok := mate.DBName2IndexCache[colName]
+		if !ok {
 			return fmt.Errorf("no corresponding field found for column %s", colName)
 		}
+		dest[i] = target.FieldByIndex(idx).Addr().Interface()
 	}
 
 	// 扫描数据

mapping_test.go

@@ -58,7 +58,7 @@ func TestBuilderInsert(t *testing.T) {
 			Ts:      time.Now(), LoadUnitId: "负载单体ID", PInt: &p, NullInt32: sql.NullInt32{Int32: 32, Valid: true},
 		},
 		&TaosUser{
-			TaosTAG: &TaosTAG{DevId: "User001", DevType: "User类型", DataType: "User数据类型001"},
+			TaosTAG: &TaosTAG{DevId: "User001", DevType: "User类型", DataType: "User数据类型001", Alias: "三儿"},
 			Ts:      time.Now(), Name: "张三",
 		}, &TaosUser{
 			TaosTAG: &TaosTAG{DevId: "User002", DevType: "User类型", DataType: "User数据类型002"},

scan.go

@@ -81,7 +81,11 @@ func scan(data interface{}) (*StructMate, error) {
 			continue
 		}
 
-		sr.Field2IndexCache[field.Name] = append(sr.Field2IndexCache[field.Name], i)
+		if len(sr.Field2IndexCache[field.Name]) > 0 {
+			return nil, fmt.Errorf("duplicate field [%s %s `db:%s`]", field.Name, field.Type.Name(), columnName)
+		}
+
+		sr.Field2IndexCache[field.Name] = append([]int{}, i)
 		sr.DBName2IndexCache[columnName] = append(sr.DBName2IndexCache[columnName], i)
 		sr.Filed2DBNameCache[field.Name] = columnName