GoDoxy/internal/gperr/subject.go
2025-04-24 15:09:46 +08:00

105 lines
2.1 KiB
Go

package gperr
import (
"encoding/json"
"errors"
"slices"
"strings"
"github.com/yusing/go-proxy/internal/utils/strutils/ansi"
)
//nolint:errname
type withSubject struct {
Subjects []string
Err error
pendingSubject string
}
const subjectSep = " > "
func highlight(subject string) string {
return ansi.HighlightRed + subject + ansi.Reset
}
func PrependSubject(subject string, err error) error {
if err == nil {
return nil
}
//nolint:errorlint
switch err := err.(type) {
case *withSubject:
return err.Prepend(subject)
case Error:
return err.Subject(subject)
}
return &withSubject{[]string{subject}, err, ""}
}
func (err *withSubject) Prepend(subject string) *withSubject {
if subject == "" {
return err
}
clone := *err
switch subject[0] {
case '[', '(', '{':
// since prepend is called in depth-first order,
// the subject of the index is not yet seen
// add it when the next subject is seen
clone.pendingSubject += subject
default:
clone.Subjects = append(clone.Subjects, subject)
if clone.pendingSubject != "" {
clone.Subjects[len(clone.Subjects)-1] = subject + clone.pendingSubject
clone.pendingSubject = ""
}
}
return &clone
}
func (err *withSubject) Is(other error) bool {
return errors.Is(other, err.Err)
}
func (err *withSubject) Unwrap() error {
return err.Err
}
func (err *withSubject) Error() string {
// subject is in reversed order
n := len(err.Subjects)
size := 0
errStr := err.Err.Error()
var sb strings.Builder
for _, s := range err.Subjects {
size += len(s)
}
sb.Grow(size + 2 + n*len(subjectSep) + len(errStr) + len(highlight("")))
for i := n - 1; i > 0; i-- {
sb.WriteString(err.Subjects[i])
sb.WriteString(subjectSep)
}
sb.WriteString(highlight(err.Subjects[0]))
sb.WriteString(": ")
sb.WriteString(errStr)
return sb.String()
}
// MarshalJSON implements the json.Marshaler interface.
func (err *withSubject) MarshalJSON() ([]byte, error) {
subjects := slices.Clone(err.Subjects)
slices.Reverse(subjects)
reversed := struct {
Subjects []string `json:"subjects"`
Err error `json:"err"`
}{
Subjects: subjects,
Err: err.Err,
}
return json.Marshal(reversed)
}