1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
|
// Copyright 2018 The etcd Authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package flags
import (
"flag"
"fmt"
"sort"
"strings"
)
// UniqueStringsValue wraps a list of unique strings.
// The values are set in order.
type UniqueStringsValue struct {
Values map[string]struct{}
}
// Set parses a command line set of strings, separated by comma.
// Implements "flag.Value" interface.
// The values are set in order.
func (us *UniqueStringsValue) Set(s string) error {
us.Values = make(map[string]struct{})
for _, v := range strings.Split(s, ",") {
us.Values[v] = struct{}{}
}
return nil
}
// String implements "flag.Value" interface.
func (us *UniqueStringsValue) String() string {
return strings.Join(us.stringSlice(), ",")
}
func (us *UniqueStringsValue) stringSlice() []string {
ss := make([]string, 0, len(us.Values))
for v := range us.Values {
ss = append(ss, v)
}
sort.Strings(ss)
return ss
}
// NewUniqueStringsValue implements string slice as "flag.Value" interface.
// Given value is to be separated by comma.
// The values are set in order.
func NewUniqueStringsValue(s string) (us *UniqueStringsValue) {
us = &UniqueStringsValue{Values: make(map[string]struct{})}
if s == "" {
return us
}
if err := us.Set(s); err != nil {
panic(fmt.Sprintf("new UniqueStringsValue should never fail: %v", err))
}
return us
}
// UniqueStringsFromFlag returns a string slice from the flag.
func UniqueStringsFromFlag(fs *flag.FlagSet, flagName string) []string {
return (*fs.Lookup(flagName).Value.(*UniqueStringsValue)).stringSlice()
}
// UniqueStringsMapFromFlag returns a map of strings from the flag.
func UniqueStringsMapFromFlag(fs *flag.FlagSet, flagName string) map[string]struct{} {
return (*fs.Lookup(flagName).Value.(*UniqueStringsValue)).Values
}
|
