| // Copyright 2018 The LUCI 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 flag |
| |
| import ( |
| "flag" |
| "strings" |
| |
| "go.chromium.org/luci/common/errors" |
| ) |
| |
| // commaListFlag implements the flag.Getter returned by CommaList. |
| type commaListFlag []string |
| |
| // CommaList returns a flag.Getter for parsing a comma |
| // separated flag argument into a string slice. |
| func CommaList(s *[]string) flag.Getter { |
| return (*commaListFlag)(s) |
| } |
| |
| // String implements the flag.Value interface. |
| func (f commaListFlag) String() string { |
| return strings.Join(f, ",") |
| } |
| |
| // Set implements the flag.Value interface. |
| func (f *commaListFlag) Set(s string) error { |
| if f == nil { |
| return errors.Reason("commaListFlag pointer is nil").Err() |
| } |
| *f = splitCommaList(s) |
| return nil |
| } |
| |
| // Get retrieves the flag value. |
| func (f commaListFlag) Get() interface{} { |
| return []string(f) |
| } |
| |
| // splitCommaList splits a comma separated string into a slice of |
| // strings. If the string is empty, return an empty slice. |
| func splitCommaList(s string) []string { |
| if s == "" { |
| return nil |
| } |
| return strings.Split(s, ",") |
| } |