mirror of https://go.googlesource.com/go
79 lines
1.7 KiB
Go
79 lines
1.7 KiB
Go
// Copyright 2018 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 fmt
|
|
|
|
import (
|
|
"errors"
|
|
"sort"
|
|
)
|
|
|
|
// Errorf formats according to a format specifier and returns the string as a
|
|
// value that satisfies error.
|
|
//
|
|
// If the format specifier includes a %w verb with an error operand,
|
|
// the returned error will implement an Unwrap method returning the operand.
|
|
// If there is more than one %w verb, the returned error will implement an
|
|
// Unwrap method returning a []error containing all the %w operands in the
|
|
// order they appear in the arguments.
|
|
// It is invalid to supply the %w verb with an operand that does not implement
|
|
// the error interface. The %w verb is otherwise a synonym for %v.
|
|
func Errorf(format string, a ...any) error {
|
|
p := newPrinter()
|
|
p.wrapErrs = true
|
|
p.doPrintf(format, a)
|
|
s := string(p.buf)
|
|
var err error
|
|
switch len(p.wrappedErrs) {
|
|
case 0:
|
|
err = errors.New(s)
|
|
case 1:
|
|
w := &wrapError{msg: s}
|
|
w.err, _ = a[p.wrappedErrs[0]].(error)
|
|
err = w
|
|
default:
|
|
if p.reordered {
|
|
sort.Ints(p.wrappedErrs)
|
|
}
|
|
var errs []error
|
|
for i, argNum := range p.wrappedErrs {
|
|
if i > 0 && p.wrappedErrs[i-1] == argNum {
|
|
continue
|
|
}
|
|
if e, ok := a[argNum].(error); ok {
|
|
errs = append(errs, e)
|
|
}
|
|
}
|
|
err = &wrapErrors{s, errs}
|
|
}
|
|
p.free()
|
|
return err
|
|
}
|
|
|
|
type wrapError struct {
|
|
msg string
|
|
err error
|
|
}
|
|
|
|
func (e *wrapError) Error() string {
|
|
return e.msg
|
|
}
|
|
|
|
func (e *wrapError) Unwrap() error {
|
|
return e.err
|
|
}
|
|
|
|
type wrapErrors struct {
|
|
msg string
|
|
errs []error
|
|
}
|
|
|
|
func (e *wrapErrors) Error() string {
|
|
return e.msg
|
|
}
|
|
|
|
func (e *wrapErrors) Unwrap() []error {
|
|
return e.errs
|
|
}
|