feat(error): add error wrapping and unwrapping support

- Implemented Unwrap method for BError and defaultErr types
- Added WrapError function to wrap errors with message prefixes
- Included comprehensive tests for error wrapping functionality
- Ensured compatibility with existing error types and interfaces

Author: Degfy

error.go

@@ -15,6 +15,8 @@ type Error interface {
 	Code() int
 
 	GetStatusCode() int
+
+	Unwrap() error
 }
 
 // InnerError which has stack, and which is used for Internal error
@@ -35,6 +37,10 @@ type BError struct {
 	data any
 }
 
+func (e *BError) Unwrap() error {
+	return e.err
+}
+
 func (e *BError) SetMsg(msg string) {
 	e.err.SetMsg(msg)
 }
@@ -60,6 +66,11 @@ type defaultErr struct {
 	code       int
 	msg        string
 	statusCode int
+	cause      error
+}
+
+func (e *defaultErr) Unwrap() error {
+	return e.cause
 }
 
 func (e *defaultErr) Error() string {
@@ -193,6 +204,16 @@ func ToErrorf(input any, format string, params ...any) error {
 	return ToErrorWithMsg(input, fmt.Sprintf(format, params...))
 }
 
+// WrapError wraps any input error with an additional message prefix.
+// Parameters:
+//
+//	input: any input error or message,
+//	format: format string for the message,
+//	params: parameters to format the message string
+func WrapError(input any, format string, params ...any) Error {
+	return ToErrorWithMsg(input, fmt.Sprintf(format, params...))
+}
+
 type iError struct {
 	*defaultErr
 	trace []byte

error_test.go

@@ -381,3 +381,50 @@ func TestToErrorf(t *testing.T) {
 
 	})
 }
+
+func TestWrapError(t *testing.T) {
+	t.Run("wrap err", func(t *testing.T) {
+		tests := []struct {
+			name string
+			err  error
+		}{
+			{
+				name: "wrap normal error",
+				err:  fmt.Errorf("normal error"),
+			},
+			{
+				name: "wrap gone InnerError",
+				err:  NewInnerError("test error", http.StatusInternalServerError),
+			},
+			{
+				name: "wrap gone BusinessError",
+				err:  NewBusinessError("test error", http.StatusOK),
+			},
+			{
+				name: "wrap gone ParameterError",
+				err:  NewParameterError("test error", http.StatusBadRequest),
+			},
+			{
+				name: "wrap gone Error",
+				err:  NewError(1101, "test error", http.StatusBadRequest),
+			},
+		}
+
+		for _, tt := range tests {
+			t.Run(tt.name, func(t *testing.T) {
+				wrapError := WrapError(tt.err, "wrap error")
+				if !errors.Is(wrapError, tt.err) {
+					t.Error("must be input error")
+				}
+			})
+		}
+	})
+	t.Run("wrap none error", func(t *testing.T) {
+		wrapError := WrapError("some thing", "wrap error")
+
+		msg := wrapError.Msg()
+		if msg != "wrap error" {
+			t.Error("must be wrap error")
+		}
+	})
+}