support implicit table alias, close #5840 #5940

Author: jinzhu

chainable_api.go

@@ -55,7 +55,7 @@ func (db *DB) Clauses(conds ...clause.Expression) (tx *DB) {
 	return
 }
 
-var tableRegexp = regexp.MustCompile(`(?i).+? AS (\w+)\s*(?:$|,)`)
+var tableRegexp = regexp.MustCompile(`(?i)(?:.+? AS (\w+)\s*(?:$|,)|^\w+\s+(\w+)$)`)
 
 // Table specify the table you would like to run db operations
 //
@@ -65,8 +65,12 @@ func (db *DB) Table(name string, args ...interface{}) (tx *DB) {
 	tx = db.getInstance()
 	if strings.Contains(name, " ") || strings.Contains(name, "`") || len(args) > 0 {
 		tx.Statement.TableExpr = &clause.Expr{SQL: name, Vars: args}
-		if results := tableRegexp.FindStringSubmatch(name); len(results) == 2 {
-			tx.Statement.Table = results[1]
+		if results := tableRegexp.FindStringSubmatch(name); len(results) == 3 {
+			if results[1] != "" {
+				tx.Statement.Table = results[1]
+			} else {
+				tx.Statement.Table = results[2]
+			}
 		}
 	} else if tables := strings.Split(name, "."); len(tables) == 2 {
 		tx.Statement.TableExpr = &clause.Expr{SQL: tx.Statement.Quote(name)}

tests/go.mod

@@ -3,13 +3,12 @@ module gorm.io/gorm/tests
 go 1.16
 
 require (
-	github.com/go-sql-driver/mysql v1.7.0 // indirect
 	github.com/google/uuid v1.3.0
 	github.com/jinzhu/now v1.1.5
 	github.com/lib/pq v1.10.7
 	github.com/mattn/go-sqlite3 v1.14.16 // indirect
 	github.com/microsoft/go-mssqldb v0.19.0 // indirect
-	gorm.io/driver/mysql v1.4.4
+	gorm.io/driver/mysql v1.4.5
 	gorm.io/driver/postgres v1.4.6
 	gorm.io/driver/sqlite v1.4.4
 	gorm.io/driver/sqlserver v1.4.1

tests/soft_delete_test.go

@@ -39,6 +39,11 @@ func TestSoftDelete(t *testing.T) {
 		t.Fatalf("invalid sql generated, got %v", sql)
 	}
 
+	sql = DB.Session(&gorm.Session{DryRun: true}).Table("user u").Select("name").Find(&User{}).Statement.SQL.String()
+	if !regexp.MustCompile(`SELECT .name. FROM user u WHERE .u.\..deleted_at. IS NULL`).MatchString(sql) {
+		t.Errorf("Table with escape character, got %v", sql)
+	}
+
 	if DB.First(&User{}, "name = ?", user.Name).Error == nil {
 		t.Errorf("Can't find a soft deleted record")
 	}