urfave-cli/flag_bool.go

150 lines
3.1 KiB
Go
Raw Permalink Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

package cli
import (
"errors"
"flag"
"fmt"
"strconv"
)
// boolValue needs to implement the boolFlag internal interface in flag
// to be able to capture bool fields and values
//
// type boolFlag interface {
// Value
// IsBoolFlag() bool
// }
type boolValue struct {
destination *bool
count *int
}
func newBoolValue(val bool, p *bool, count *int) *boolValue {
*p = val
return &boolValue{
destination: p,
count: count,
}
}
func (b *boolValue) Set(s string) error {
v, err := strconv.ParseBool(s)
if err != nil {
err = errors.New("parse error")
return err
}
*b.destination = v
if b.count != nil {
*b.count = *b.count + 1
}
return err
}
func (b *boolValue) Get() interface{} { return *b.destination }
func (b *boolValue) String() string {
if b.destination != nil {
return strconv.FormatBool(*b.destination)
}
return strconv.FormatBool(false)
}
func (b *boolValue) IsBoolFlag() bool { return true }
func (b *boolValue) Count() int {
if b.count != nil {
return *b.count
}
return 0
}
// GetValue returns the flags value as string representation and an empty
// string if the flag takes no value at all.
func (f *BoolFlag) GetValue() string {
return ""
}
// GetDefaultText returns the default text for this flag
func (f *BoolFlag) GetDefaultText() string {
if f.DefaultText != "" {
return f.DefaultText
}
return fmt.Sprintf("%v", f.defaultValue)
}
// RunAction executes flag action if set
func (f *BoolFlag) RunAction(c *Context) error {
if f.Action != nil {
return f.Action(c, c.Bool(f.Name))
}
return nil
}
// Apply populates the flag given the flag set and environment
func (f *BoolFlag) Apply(set *flag.FlagSet) error {
// set default value so that environment wont be able to overwrite it
f.defaultValue = f.Value
if val, source, found := flagFromEnvOrFile(f.EnvVars, f.FilePath); found {
if val != "" {
valBool, err := strconv.ParseBool(val)
if err != nil {
return fmt.Errorf("could not parse %q as bool value from %s for flag %s: %s", val, source, f.Name, err)
}
f.Value = valBool
} else {
// empty value implies that the env is defined but set to empty string, we have to assume that this is
// what the user wants. If user doesnt want this then the env needs to be deleted or the flag removed from
// file
f.Value = false
}
f.HasBeenSet = true
}
count := f.Count
dest := f.Destination
if count == nil {
count = new(int)
}
if dest == nil {
dest = new(bool)
}
for _, name := range f.Names() {
value := newBoolValue(f.Value, dest, count)
set.Var(value, name, f.Usage)
}
return nil
}
// Get returns the flags value in the given Context.
func (f *BoolFlag) Get(ctx *Context) bool {
return ctx.Bool(f.Name)
}
// Bool looks up the value of a local BoolFlag, returns
// false if not found
func (cCtx *Context) Bool(name string) bool {
if fs := cCtx.lookupFlagSet(name); fs != nil {
return lookupBool(name, fs)
}
return false
}
func lookupBool(name string, set *flag.FlagSet) bool {
f := set.Lookup(name)
if f != nil {
parsed, err := strconv.ParseBool(f.Value.String())
if err != nil {
return false
}
return parsed
}
return false
}