go.chromium.org/luci@v0.0.0-20240309015107-7cdc2e660f33/common/flag/boolslice.go (about)

     1  // Copyright 2019 The LUCI Authors.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //      http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package flag
    16  
    17  import (
    18  	"flag"
    19  	"strconv"
    20  	"strings"
    21  
    22  	"go.chromium.org/luci/common/errors"
    23  )
    24  
    25  // boolSliceFlag is a flag.Getter implementation representing an []bool.
    26  type boolSliceFlag []bool
    27  
    28  // String returns a comma-separated string representation of the flag values.
    29  func (f boolSliceFlag) String() string {
    30  	s := make([]string, len(f))
    31  	for n, i := range f {
    32  		s[n] = strconv.FormatBool(i)
    33  	}
    34  	return strings.Join(s, ", ")
    35  }
    36  
    37  // Set records seeing a flag value.
    38  func (f *boolSliceFlag) Set(val string) error {
    39  	b, err := strconv.ParseBool(val)
    40  	if err != nil {
    41  		return errors.Reason("values must be booleans").Err()
    42  	}
    43  	*f = append(*f, b)
    44  	return nil
    45  }
    46  
    47  // Get retrieves the flag value.
    48  func (f boolSliceFlag) Get() any {
    49  	return []bool(f)
    50  }
    51  
    52  // BoolSlice returns a flag.Getter which reads flags into the given []bool pointer.
    53  func BoolSlice(b *[]bool) flag.Getter {
    54  	return (*boolSliceFlag)(b)
    55  }