| // Copyright 2024 The Go Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style |
| // license that can be found in the LICENSE file. |
| |
| // Package errutil provides utilities for easily annotating Go errors. |
| package errutil |
| |
| import "fmt" |
| |
| // Annotatef annotates non-nil error with the given message. |
| // |
| // It's designed to be used in a defer, for example: |
| // |
| // func g(arg string) (err error) { |
| // defer Annotate(&err, fmt.Sprintf("g(%s)") |
| // return errors.New("my error") |
| // } |
| // |
| // Calling g("hello") will result in error message: |
| // |
| // g(hello): my error |
| // |
| // Annotate allows using the above short form instead of the long form: |
| // |
| // func g(arg string) (err error) { |
| // defer func() { |
| // if err != nil { |
| // err = fmt.Errorf("g(%s): %v", arg, err) |
| // } |
| // }() |
| // return errors.New("my error") |
| // } |
| func Annotatef(err *error, format string, a ...any) { |
| if *err != nil { |
| *err = fmt.Errorf("%s: %v", fmt.Sprintf(format, a...), *err) |
| } |
| } |
