cmd/gf: fix command gf gen dao for fieldMapping feature (#3549)

Author: cyjaysong

cmd/gf/internal/cmd/cmd_z_unit_gen_dao_test.go

@@ -241,7 +241,7 @@ func Test_Gen_Dao_FieldMapping(t *testing.T) {
 			in    = gendao.CGenDaoInput{
 				Path:               path,
 				Link:               link,
-				Tables:             "table_user",
+				Tables:             "",
 				TablesEx:           "",
 				Group:              group,
 				Prefix:             "",

cmd/gf/internal/cmd/gendao/gendao_structure.go

@@ -133,7 +133,7 @@ func generateStructFieldDefinition(
 	}
 
 	if in.FieldMapping != nil && len(in.FieldMapping) > 0 {
-		if typeMapping, ok := in.FieldMapping[fmt.Sprintf("%s.%s", in.Tables, newFiledName)]; ok {
+		if typeMapping, ok := in.FieldMapping[fmt.Sprintf("%s.%s", in.TableName, newFiledName)]; ok {
 			localTypeNameStr = typeMapping.Type
 			appendImport = typeMapping.Import
 		}

os/gfile/gfile_replace.go

@@ -19,7 +19,7 @@ func ReplaceFile(search, replace, path string) error {
 func ReplaceFileFunc(f func(path, content string) string, path string) error {
 	data := GetContents(path)
 	result := f(path, data)
-	if len(data) != len(result) && data != result {
+	if len(data) != len(result) || data != result {
 		return PutContents(path, result)
 	}
 	return nil