Try to implement the FirstOrInit method

chain.go

@@ -35,6 +35,11 @@ func (s *Chain) err(err error) error {
 	return err
 }
 
+func (s *Chain) deleteLastError() {
+	s.Error = nil
+	s.Errors = s.Errors[:len(s.Errors)-1]
+}
+
 func (s *Chain) do(value interface{}) *Do {
 	var do Do
 	do.chain = s
@@ -160,6 +165,10 @@ func (s *Chain) First(out interface{}, where ...interface{}) *Chain {
 }
 
 func (s *Chain) FirstOrInit(out interface{}, where ...interface{}) *Chain {
+	if s.First(out).Error != nil {
+		s.do(out).initializedWithSearchCondition()
+		s.deleteLastError()
+	}
 	return s
 }
 

do.go

@@ -350,14 +350,14 @@ func (s *Do) buildWhereCondition(clause map[string]interface{}) (str string) {
 		for key, value := range query.(map[string]interface{}) {
 			sqls = append(sqls, fmt.Sprintf(" ( %v = %v ) ", key, s.addToVars(value)))
 		}
-		return strings.Join(sqls, ",")
+		return strings.Join(sqls, " AND ")
 	case interface{}:
 		m := &Model{data: query, driver: s.driver}
 		var sqls []string
 		for _, field := range m.columnsHasValue("") {
 			sqls = append(sqls, fmt.Sprintf(" ( %v = %v ) ", field.DbName, s.addToVars(field.Value)))
 		}
-		return strings.Join(sqls, ",")
+		return strings.Join(sqls, " AND ")
 	}
 
 	args := clause["args"].([]interface{})
@@ -383,7 +383,6 @@ func (s *Do) whereSql() (sql string) {
 	if !s.unscoped && s.model.hasColumn("DeletedAt") {
 		primary_condiations = append(primary_condiations, "(deleted_at is null or deleted_at <= '0001-01-02')")
 	}
-
 	if !s.model.primaryKeyZero() {
 		primary_condiations = append(primary_condiations, s.primaryCondiation(s.addToVars(s.model.primaryKeyValue())))
 	}
@@ -466,3 +465,22 @@ func (s *Do) createTable() *Do {
 	)
 	return s
 }
+
+func (s *Do) initializedWithSearchCondition() {
+	m := Model{data: s.value, driver: s.driver}
+
+	for _, clause := range s.whereClause {
+		query := clause["query"]
+		switch query.(type) {
+		case map[string]interface{}:
+			for key, value := range query.(map[string]interface{}) {
+				m.setValueByColumn(key, value, s.value)
+			}
+		case interface{}:
+			m := &Model{data: query, driver: s.driver}
+			for _, field := range m.columnsHasValue("") {
+				m.setValueByColumn(field.DbName, field.Value, s.value)
+			}
+		}
+	}
+}

gorm_test.go

@@ -799,9 +799,14 @@ func TestSoftDelete(t *testing.T) {
 }
 
 func TestFindOrInitialize(t *testing.T) {
-	var user User
-	db.Where(User{Name: "hello world"}).FirstOrInit(&user)
-	if user.Name != "hello world" || user.Id != 0 {
+	var user1 User
+	db.Where(&User{Name: "hello world", Age: 33}).FirstOrInit(&user1)
+	if user1.Name != "hello world" || user1.Id != 0 || user1.Age != 33 {
 		t.Errorf("user should be initialized with search value")
 	}
+
+	// db.FirstOrInit(&user2, map[string]interface{}{"name": "hahaha"})
+	// if user2.Name != "hahaha" || user2.Id != 0 {
+	// 	t.Errorf("user should be initialized with search value")
+	// }
 }

model.go

@@ -188,13 +188,21 @@ func (m *Model) callMethod(method string) error {
 	return nil
 }
 
-func (model *Model) returningStr() (str string) {
-	if model.driver == "postgres" {
-		str = fmt.Sprintf("RETURNING \"%v\"", model.primaryKeyDb())
+func (m *Model) returningStr() (str string) {
+	if m.driver == "postgres" {
+		str = fmt.Sprintf("RETURNING \"%v\"", m.primaryKeyDb())
 	}
 	return
 }
 
-func (model *Model) missingColumns() (results []string) {
+func (m *Model) missingColumns() (results []string) {
 	return
 }
+
+func (m *Model) setValueByColumn(name string, value interface{}, out interface{}) {
+	data := reflect.ValueOf(out).Elem()
+	field := data.FieldByName(snakeToUpperCamel(name))
+	if field.IsValid() {
+		field.Set(reflect.ValueOf(value))
+	}
+}