errors_join.go

// Copyright (c) 2023 Benjamin Borbe All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

package errors

func Join(errs ...error) error {
	n := 0
	for _, err := range errs {
		if err != nil {
			n++
		}
	}
	if n == 0 {
		return nil
	}
	e := &joinError{
		errs: make([]error, 0, n),
	}
	for _, err := range errs {
		if err != nil {
			e.errs = append(e.errs, err)
		}
	}
	return e
}

type joinError struct {
	errs []error
}

func (e *joinError) Error() string {
	var b []byte
	b = append(b, '[', '\n')
	for _, err := range e.errs {
		b = append(b, err.Error()...)
		b = append(b, '\n')
	}
	b = append(b, ']')
	return string(b)
}

func (e *joinError) Unwrap() []error {
	return e.errs
}