feat: support go1.13 errors.Is

error_12.go

@@ -0,0 +1,7 @@
+// +build !go1.13
+
+package gorm
+
+func isError(err, target error) bool {
+	return err == target
+}

error_13.go

@@ -0,0 +1,7 @@
+// +build go1.13
+
+package gorm
+
+import "errors"
+
+var isError = errors.Is

errors.go

@@ -25,12 +25,12 @@ type Errors []error
 func IsRecordNotFoundError(err error) bool {
 	if errs, ok := err.(Errors); ok {
 		for _, err := range errs {
-			if err == ErrRecordNotFound {
+			if isError(err, ErrRecordNotFound) {
 				return true
 			}
 		}
 	}
-	return err == ErrRecordNotFound
+	return isError(err, ErrRecordNotFound)
 }
 
 // GetErrors gets all errors that have occurred and returns a slice of errors (Error type)

main.go

@@ -592,7 +592,7 @@ func (s *DB) NewRecord(value interface{}) bool {
 // RecordNotFound check if returning ErrRecordNotFound error
 func (s *DB) RecordNotFound() bool {
 	for _, err := range s.GetErrors() {
-		if err == ErrRecordNotFound {
+		if isError(err, ErrRecordNotFound) {
 			return true
 		}
 	}
@@ -776,7 +776,7 @@ func (s *DB) SetJoinTableHandler(source interface{}, column string, handler Join
 // AddError add error to the db
 func (s *DB) AddError(err error) error {
 	if err != nil {
-		if err != ErrRecordNotFound {
+		if !isError(err, ErrRecordNotFound) {
 			if s.logMode == defaultLogMode {
 				go s.print("error", fileWithLineNum(), err)
 			} else {