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author | Christopher Speller <crspeller@gmail.com> | 2016-12-06 10:49:34 -0500 |
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committer | GitHub <noreply@github.com> | 2016-12-06 10:49:34 -0500 |
commit | 026553e4f87bfc647a5c03129752e30fc523fa07 (patch) | |
tree | d5403c760151c0fa26fc6d020f7f4326ea9d6f8a /vendor/github.com/spf13/pflag/golangflag.go | |
parent | dcf11a14d8363c79ab62aefca46834d6daa615ab (diff) | |
download | chat-026553e4f87bfc647a5c03129752e30fc523fa07.tar.gz chat-026553e4f87bfc647a5c03129752e30fc523fa07.tar.bz2 chat-026553e4f87bfc647a5c03129752e30fc523fa07.zip |
Improving command line interface (#4689)
Diffstat (limited to 'vendor/github.com/spf13/pflag/golangflag.go')
-rw-r--r-- | vendor/github.com/spf13/pflag/golangflag.go | 104 |
1 files changed, 104 insertions, 0 deletions
diff --git a/vendor/github.com/spf13/pflag/golangflag.go b/vendor/github.com/spf13/pflag/golangflag.go new file mode 100644 index 000000000..b056147fd --- /dev/null +++ b/vendor/github.com/spf13/pflag/golangflag.go @@ -0,0 +1,104 @@ +// Copyright 2009 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package pflag + +import ( + goflag "flag" + "fmt" + "reflect" + "strings" +) + +var _ = fmt.Print + +// flagValueWrapper implements pflag.Value around a flag.Value. The main +// difference here is the addition of the Type method that returns a string +// name of the type. As this is generally unknown, we approximate that with +// reflection. +type flagValueWrapper struct { + inner goflag.Value + flagType string +} + +// We are just copying the boolFlag interface out of goflag as that is what +// they use to decide if a flag should get "true" when no arg is given. +type goBoolFlag interface { + goflag.Value + IsBoolFlag() bool +} + +func wrapFlagValue(v goflag.Value) Value { + // If the flag.Value happens to also be a pflag.Value, just use it directly. + if pv, ok := v.(Value); ok { + return pv + } + + pv := &flagValueWrapper{ + inner: v, + } + + t := reflect.TypeOf(v) + if t.Kind() == reflect.Interface || t.Kind() == reflect.Ptr { + t = t.Elem() + } + + pv.flagType = strings.TrimSuffix(t.Name(), "Value") + return pv +} + +func (v *flagValueWrapper) String() string { + return v.inner.String() +} + +func (v *flagValueWrapper) Set(s string) error { + return v.inner.Set(s) +} + +func (v *flagValueWrapper) Type() string { + return v.flagType +} + +// PFlagFromGoFlag will return a *pflag.Flag given a *flag.Flag +// If the *flag.Flag.Name was a single character (ex: `v`) it will be accessiblei +// with both `-v` and `--v` in flags. If the golang flag was more than a single +// character (ex: `verbose`) it will only be accessible via `--verbose` +func PFlagFromGoFlag(goflag *goflag.Flag) *Flag { + // Remember the default value as a string; it won't change. + flag := &Flag{ + Name: goflag.Name, + Usage: goflag.Usage, + Value: wrapFlagValue(goflag.Value), + // Looks like golang flags don't set DefValue correctly :-( + //DefValue: goflag.DefValue, + DefValue: goflag.Value.String(), + } + // Ex: if the golang flag was -v, allow both -v and --v to work + if len(flag.Name) == 1 { + flag.Shorthand = flag.Name + } + if fv, ok := goflag.Value.(goBoolFlag); ok && fv.IsBoolFlag() { + flag.NoOptDefVal = "true" + } + return flag +} + +// AddGoFlag will add the given *flag.Flag to the pflag.FlagSet +func (f *FlagSet) AddGoFlag(goflag *goflag.Flag) { + if f.Lookup(goflag.Name) != nil { + return + } + newflag := PFlagFromGoFlag(goflag) + f.AddFlag(newflag) +} + +// AddGoFlagSet will add the given *flag.FlagSet to the pflag.FlagSet +func (f *FlagSet) AddGoFlagSet(newSet *goflag.FlagSet) { + if newSet == nil { + return + } + newSet.VisitAll(func(goflag *goflag.Flag) { + f.AddGoFlag(goflag) + }) +} |