add Is/Equal/Unwrap functions for package gerror

errors/gerror/gerror_interface.go

@@ -0,0 +1,51 @@
+// Copyright GoFrame Author(https://goframe.org). All Rights Reserved.
+//
+// This Source Code Form is subject to the terms of the MIT License.
+// If a copy of the MIT was not distributed with this file,
+// You can obtain one at https://github.com/gogf/gf.
+
+package gerror
+
+import (
+	"github.com/gogf/gf/v2/errors/gcode"
+)
+
+// iIs is the interface for Is feature.
+type iIs interface {
+	Is(target error) bool
+}
+
+// iEqual is the interface for Equal feature.
+type iEqual interface {
+	Equal(target error) bool
+}
+
+// iCode is the interface for Code feature.
+type iCode interface {
+	Error() string
+	Code() gcode.Code
+}
+
+// iStack is the interface for Stack feature.
+type iStack interface {
+	Error() string
+	Stack() string
+}
+
+// iCause is the interface for Cause feature.
+type iCause interface {
+	Error() string
+	Cause() error
+}
+
+// iCurrent is the interface for Current feature.
+type iCurrent interface {
+	Error() string
+	Current() error
+}
+
+// iNext is the interface for Next feature.
+type iNext interface {
+	Error() string
+	Next() error
+}