badguardhome/internal/aghstrings/strings.go
Eugene Burkov 3f1fd56b17 Pull request: 3172 fix mobileconfig
Merge in DNS/adguard-home from 3172-mobileconfig to master

Updates #3172.
Updates #2497.

Squashed commit of the following:

commit 30549ef4eda9d88f0738089e901492d7369caa25
Author: Eugene Burkov <e.burkov@adguard.com>
Date:   Tue Jun 1 21:00:17 2021 +0300

    all: log changes

commit 9b9429447430a8e5656b992c04c4a74606dc5f9f
Author: Ildar Kamalov <ik@adguard.com>
Date:   Tue Jun 1 17:56:59 2021 +0300

    client: always show port input

commit 6d6a0bdfaa849220a5ddb4a17502ab05379d7a1c
Merge: 13a3bffd 77946a7f
Author: Eugene Burkov <e.burkov@adguard.com>
Date:   Tue Jun 1 17:50:41 2021 +0300

    Merge branch 'master' into 3172-mobileconfig

commit 13a3bffd4dd6ccabf3d261f17b2c758a5c61eb9c
Author: Ildar Kamalov <ik@adguard.com>
Date:   Tue Jun 1 17:20:17 2021 +0300

    client: add port to mobile config form

commit f6abe0b6044572f3801c31b683e76f90c4a28487
Author: Eugene Burkov <e.burkov@adguard.com>
Date:   Mon May 31 19:43:37 2021 +0300

    home: imp cyclo

commit c304a0bacdca6f8b5ffd21f3d00c8244ea9e4e36
Author: Eugene Burkov <e.burkov@adguard.com>
Date:   Mon May 31 18:19:46 2021 +0300

    home: reduce allocs

commit 10a7678861079b710bb0ef14569c60a09612ec70
Author: Eugene Burkov <e.burkov@adguard.com>
Date:   Mon May 24 20:05:08 2021 +0300

    all: make the host parameter required
2021-06-01 21:06:55 +03:00

104 lines
2.2 KiB
Go

// Package aghstrings contains utilities dealing with strings.
package aghstrings
import (
"strings"
)
// CloneSliceOrEmpty returns the copy of a or empty strings slice if a is nil.
func CloneSliceOrEmpty(a []string) (b []string) {
return append([]string{}, a...)
}
// CloneSlice returns the exact copy of a.
func CloneSlice(a []string) (b []string) {
if a == nil {
return nil
}
return CloneSliceOrEmpty(a)
}
// Coalesce returns the first non-empty string. It is named after the function
// COALESCE in SQL except that since strings in Go are non-nullable, it uses an
// empty string as a NULL value. If strs or all it's elements are empty, it
// returns an empty string.
func Coalesce(strs ...string) (res string) {
for _, s := range strs {
if s != "" {
return s
}
}
return ""
}
// FilterOut returns a copy of strs with all strings for which f returned true
// removed.
func FilterOut(strs []string, f func(s string) (ok bool)) (filtered []string) {
for _, s := range strs {
if !f(s) {
filtered = append(filtered, s)
}
}
return filtered
}
// InSlice checks if string is in the slice of strings.
func InSlice(strs []string, str string) (ok bool) {
for _, s := range strs {
if s == str {
return true
}
}
return false
}
// IsCommentOrEmpty returns true of the string starts with a "#" character or is
// an empty string.
func IsCommentOrEmpty(s string) (ok bool) {
return len(s) == 0 || s[0] == '#'
}
// SplitNext splits string by a byte and returns the first chunk skipping empty
// ones. Whitespaces are trimmed.
func SplitNext(s *string, sep rune) (chunk string) {
if s == nil {
return chunk
}
i := strings.IndexByte(*s, byte(sep))
if i == -1 {
chunk = *s
*s = ""
return strings.TrimSpace(chunk)
}
chunk = (*s)[:i]
*s = (*s)[i+1:]
var j int
var r rune
for j, r = range *s {
if r != sep {
break
}
}
*s = (*s)[j:]
return strings.TrimSpace(chunk)
}
// WriteToBuilder is a convenient wrapper for strings.(*Builder).WriteString
// that deals with multiple strings and ignores errors that are guaranteed to be
// nil.
func WriteToBuilder(b *strings.Builder, strs ...string) {
// TODO(e.burkov): Recover from panic?
for _, s := range strs {
_, _ = b.WriteString(s)
}
}