badguardhome/internal/agherr/agherr.go
Ainar Garipov 13f708b483 Pull request: * querylog: fix end of log handling
Merge in DNS/adguard-home from 2229-query-log to master

Closes #2229.

Squashed commit of the following:

commit 32508a3f3b1e098869e1649a2774f1f17d14d41f
Author: Ainar Garipov <A.Garipov@AdGuard.COM>
Date:   Tue Nov 10 16:51:25 2020 +0300

    * querylog: add test

commit 774159cc313a0284a8bb8327489671e5d7a3e4eb
Author: Ainar Garipov <A.Garipov@AdGuard.COM>
Date:   Tue Nov 10 15:26:26 2020 +0300

    * querylog: better errors

commit 27b13a4dcaff9e8f9b08aec81c0c03f62ebd3fa5
Author: Ainar Garipov <A.Garipov@AdGuard.COM>
Date:   Tue Nov 10 15:18:51 2020 +0300

    * querylog: fix end of log handling
2020-11-10 19:00:55 +03:00

68 lines
1.5 KiB
Go

// Package agherr contains the extended error type, and the function for
// wrapping several errors.
package agherr
import (
"fmt"
"strings"
)
// Error is the constant error type.
type Error string
// Error implements the error interface for Error.
func (err Error) Error() (msg string) {
return string(err)
}
// manyError is an error containing several wrapped errors. It is created to be
// a simpler version of the API provided by github.com/joomcode/errorx.
type manyError struct {
message string
underlying []error
}
// Many wraps several errors and returns a single error.
func Many(message string, underlying ...error) error {
err := &manyError{
message: message,
underlying: underlying,
}
return err
}
// Error implements the error interface for *manyError.
func (e *manyError) Error() string {
switch len(e.underlying) {
case 0:
return e.message
case 1:
return fmt.Sprintf("%s: %s", e.message, e.underlying[0])
default:
b := &strings.Builder{}
// Ignore errors, since strings.(*Buffer).Write never returns
// errors.
_, _ = fmt.Fprintf(b, "%s: %s (hidden: %s", e.message, e.underlying[0], e.underlying[1])
for _, u := range e.underlying[2:] {
// See comment above.
_, _ = fmt.Fprintf(b, ", %s", u)
}
// See comment above.
_, _ = b.WriteString(")")
return b.String()
}
}
// Unwrap implements the hidden errors.wrapper interface for *manyError.
func (e *manyError) Unwrap() error {
if len(e.underlying) == 0 {
return nil
}
return e.underlying[0]
}