string_slice.go

  1package pflag
  2
  3import (
  4	"bytes"
  5	"encoding/csv"
  6	"strings"
  7)
  8
  9// -- stringSlice Value
 10type stringSliceValue struct {
 11	value   *[]string
 12	changed bool
 13}
 14
 15func newStringSliceValue(val []string, p *[]string) *stringSliceValue {
 16	ssv := new(stringSliceValue)
 17	ssv.value = p
 18	*ssv.value = val
 19	return ssv
 20}
 21
 22func readAsCSV(val string) ([]string, error) {
 23	if val == "" {
 24		return []string{}, nil
 25	}
 26	stringReader := strings.NewReader(val)
 27	csvReader := csv.NewReader(stringReader)
 28	return csvReader.Read()
 29}
 30
 31func writeAsCSV(vals []string) (string, error) {
 32	b := &bytes.Buffer{}
 33	w := csv.NewWriter(b)
 34	err := w.Write(vals)
 35	if err != nil {
 36		return "", err
 37	}
 38	w.Flush()
 39	return strings.TrimSuffix(b.String(), "\n"), nil
 40}
 41
 42func (s *stringSliceValue) Set(val string) error {
 43	v, err := readAsCSV(val)
 44	if err != nil {
 45		return err
 46	}
 47	if !s.changed {
 48		*s.value = v
 49	} else {
 50		*s.value = append(*s.value, v...)
 51	}
 52	s.changed = true
 53	return nil
 54}
 55
 56func (s *stringSliceValue) Type() string {
 57	return "stringSlice"
 58}
 59
 60func (s *stringSliceValue) String() string {
 61	str, _ := writeAsCSV(*s.value)
 62	return "[" + str + "]"
 63}
 64
 65func (s *stringSliceValue) Append(val string) error {
 66	*s.value = append(*s.value, val)
 67	return nil
 68}
 69
 70func (s *stringSliceValue) Replace(val []string) error {
 71	*s.value = val
 72	return nil
 73}
 74
 75func (s *stringSliceValue) GetSlice() []string {
 76	return *s.value
 77}
 78
 79func stringSliceConv(sval string) (interface{}, error) {
 80	sval = sval[1 : len(sval)-1]
 81	// An empty string would cause a slice with one (empty) string
 82	if len(sval) == 0 {
 83		return []string{}, nil
 84	}
 85	return readAsCSV(sval)
 86}
 87
 88// GetStringSlice return the []string value of a flag with the given name
 89func (f *FlagSet) GetStringSlice(name string) ([]string, error) {
 90	val, err := f.getFlagType(name, "stringSlice", stringSliceConv)
 91	if err != nil {
 92		return []string{}, err
 93	}
 94	return val.([]string), nil
 95}
 96
 97// StringSliceVar defines a string flag with specified name, default value, and usage string.
 98// The argument p points to a []string variable in which to store the value of the flag.
 99// Compared to StringArray flags, StringSlice flags take comma-separated value as arguments and split them accordingly.
100// For example:
101//   --ss="v1,v2" --ss="v3"
102// will result in
103//   []string{"v1", "v2", "v3"}
104func (f *FlagSet) StringSliceVar(p *[]string, name string, value []string, usage string) {
105	f.VarP(newStringSliceValue(value, p), name, "", usage)
106}
107
108// StringSliceVarP is like StringSliceVar, but accepts a shorthand letter that can be used after a single dash.
109func (f *FlagSet) StringSliceVarP(p *[]string, name, shorthand string, value []string, usage string) {
110	f.VarP(newStringSliceValue(value, p), name, shorthand, usage)
111}
112
113// StringSliceVar defines a string flag with specified name, default value, and usage string.
114// The argument p points to a []string variable in which to store the value of the flag.
115// Compared to StringArray flags, StringSlice flags take comma-separated value as arguments and split them accordingly.
116// For example:
117//   --ss="v1,v2" --ss="v3"
118// will result in
119//   []string{"v1", "v2", "v3"}
120func StringSliceVar(p *[]string, name string, value []string, usage string) {
121	CommandLine.VarP(newStringSliceValue(value, p), name, "", usage)
122}
123
124// StringSliceVarP is like StringSliceVar, but accepts a shorthand letter that can be used after a single dash.
125func StringSliceVarP(p *[]string, name, shorthand string, value []string, usage string) {
126	CommandLine.VarP(newStringSliceValue(value, p), name, shorthand, usage)
127}
128
129// StringSlice defines a string flag with specified name, default value, and usage string.
130// The return value is the address of a []string variable that stores the value of the flag.
131// Compared to StringArray flags, StringSlice flags take comma-separated value as arguments and split them accordingly.
132// For example:
133//   --ss="v1,v2" --ss="v3"
134// will result in
135//   []string{"v1", "v2", "v3"}
136func (f *FlagSet) StringSlice(name string, value []string, usage string) *[]string {
137	p := []string{}
138	f.StringSliceVarP(&p, name, "", value, usage)
139	return &p
140}
141
142// StringSliceP is like StringSlice, but accepts a shorthand letter that can be used after a single dash.
143func (f *FlagSet) StringSliceP(name, shorthand string, value []string, usage string) *[]string {
144	p := []string{}
145	f.StringSliceVarP(&p, name, shorthand, value, usage)
146	return &p
147}
148
149// StringSlice defines a string flag with specified name, default value, and usage string.
150// The return value is the address of a []string variable that stores the value of the flag.
151// Compared to StringArray flags, StringSlice flags take comma-separated value as arguments and split them accordingly.
152// For example:
153//   --ss="v1,v2" --ss="v3"
154// will result in
155//   []string{"v1", "v2", "v3"}
156func StringSlice(name string, value []string, usage string) *[]string {
157	return CommandLine.StringSliceP(name, "", value, usage)
158}
159
160// StringSliceP is like StringSlice, but accepts a shorthand letter that can be used after a single dash.
161func StringSliceP(name, shorthand string, value []string, usage string) *[]string {
162	return CommandLine.StringSliceP(name, shorthand, value, usage)
163}