Autogenerate compflag code

compflag/compflag.go

@@ -36,13 +36,11 @@ package compflag
 
 import (
 	"flag"
-	"fmt"
 	"os"
 	"strconv"
 	"time"
 
 	"github.com/posener/complete/v2"
-	"github.com/posener/complete/v2/predict"
 )
 
 // FlagSet is bash completion enabled flag.FlagSet.
@@ -69,30 +67,6 @@ func (fs *FlagSet) Complete() {
 	complete.Complete(fs.Name(), complete.FlagSet((*flag.FlagSet)(CommandLine)))
 }
 
-func (fs *FlagSet) String(name string, value string, usage string, options ...predict.Option) *string {
-	p := new(string)
-	(*flag.FlagSet)(fs).Var(newStringValue(value, p, predict.Options(options...)), name, usage)
-	return p
-}
-
-func (fs *FlagSet) Bool(name string, value bool, usage string, options ...predict.Option) *bool {
-	p := new(bool)
-	(*flag.FlagSet)(fs).Var(newBoolValue(value, p, predict.Options(options...)), name, usage)
-	return p
-}
-
-func (fs *FlagSet) Int(name string, value int, usage string, options ...predict.Option) *int {
-	p := new(int)
-	(*flag.FlagSet)(fs).Var(newIntValue(value, p, predict.Options(options...)), name, usage)
-	return p
-}
-
-func (fs *FlagSet) Duration(name string, value time.Duration, usage string, options ...predict.Option) *time.Duration {
-	p := new(time.Duration)
-	(*flag.FlagSet)(fs).Var(newDurationValue(value, p, predict.Options(options...)), name, usage)
-	return p
-}
-
 var CommandLine = (*FlagSet)(flag.CommandLine)
 
 // Parse parses command line arguments. It also performs bash completion when needed.
@@ -101,164 +75,28 @@ func Parse() {
 	CommandLine.Parse(os.Args[1:])
 }
 
-func String(name string, value string, usage string, options ...predict.Option) *string {
+func predictBool(value bool, prefix string) []string {
-	return CommandLine.String(name, value, usage, options...)
-}
-
-func Bool(name string, value bool, usage string, options ...predict.Option) *bool {
-	return CommandLine.Bool(name, value, usage, options...)
-}
-
-func Int(name string, value int, usage string, options ...predict.Option) *int {
-	return CommandLine.Int(name, value, usage, options...)
-}
-
-func Duration(name string, value time.Duration, usage string, options ...predict.Option) *time.Duration {
-	return CommandLine.Duration(name, value, usage, options...)
-}
-
-type boolValue struct {
-	v *bool
-	predict.Config
-}
-
-func newBoolValue(val bool, p *bool, c predict.Config) *boolValue {
-	*p = val
-	return &boolValue{v: p, Config: c}
-}
-
-func (b *boolValue) Set(val string) error {
-	v, err := strconv.ParseBool(val)
-	*b.v = v
-	if err != nil {
-		return fmt.Errorf("bad value for bool flag")
-	}
-	return b.Check(val)
-}
-
-func (b *boolValue) Get() interface{} { return *b.v }
-
-func (b *boolValue) String() string {
-	if b == nil || b.v == nil {
-		return strconv.FormatBool(false)
-	}
-	return strconv.FormatBool(*b.v)
-}
-
-func (b *boolValue) IsBoolFlag() bool { return true }
-
-func (b *boolValue) Predict(prefix string) []string {
-	if b.Predictor != nil {
-		return b.Predictor.Predict(prefix)
-	}
 	// If false, typing the bool flag is expected to turn it on, so there is nothing to complete
 	// after the flag.
-	if !*b.v {
+	if !value {
 		return nil
 	}
 	// Otherwise, suggest only to turn it off.
 	return []string{"false"}
 }
 
-type stringValue struct {
+func parseString(s string) (string, error) { return s, nil }
-	v *string
-	predict.Config
-}
 
-func newStringValue(val string, p *string, c predict.Config) *stringValue {
+func formatString(v string) string { return v }
-	*p = val
-	return &stringValue{v: p, Config: c}
-}
 
-func (s *stringValue) Set(val string) error {
+func parseInt(s string) (int, error) { return strconv.Atoi(s) }
-	*s.v = val
-	return s.Check(val)
-}
 
-func (s *stringValue) Get() interface{} {
+func formatInt(v int) string { return strconv.Itoa(v) }
-	return *s.v
-}
 
-func (s *stringValue) String() string {
+func parseBool(s string) (bool, error) { return strconv.ParseBool(s) }
-	if s == nil || s.v == nil {
-		return ""
-	}
-	return *s.v
-}
 
-func (s *stringValue) Predict(prefix string) []string {
+func formatBool(v bool) string { return strconv.FormatBool(v) }
-	if s.Predictor != nil {
-		return s.Predictor.Predict(prefix)
-	}
-	return []string{""}
-}
 
-type intValue struct {
+func parseDuration(s string) (time.Duration, error) { return time.ParseDuration(s) }
-	v *int
-	predict.Config
-}
 
-func newIntValue(val int, p *int, c predict.Config) *intValue {
+func formatDuration(v time.Duration) string { return v.String() }
-	*p = val
-	return &intValue{v: p, Config: c}
-}
-
-func (i *intValue) Set(val string) error {
-	v, err := strconv.ParseInt(val, 0, strconv.IntSize)
-	*i.v = int(v)
-	if err != nil {
-		return fmt.Errorf("bad value for int flag")
-	}
-	return i.Check(val)
-}
-
-func (i *intValue) Get() interface{} { return *i.v }
-
-func (i *intValue) String() string {
-	if i == nil || i.v == nil {
-		return strconv.Itoa(0)
-	}
-	return strconv.Itoa(*i.v)
-}
-
-func (s *intValue) Predict(prefix string) []string {
-	if s.Predictor != nil {
-		return s.Predictor.Predict(prefix)
-	}
-	return []string{""}
-}
-
-type durationValue struct {
-	v *time.Duration
-	predict.Config
-}
-
-func newDurationValue(val time.Duration, p *time.Duration, c predict.Config) *durationValue {
-	*p = val
-	return &durationValue{v: p, Config: c}
-}
-
-func (i *durationValue) Set(val string) error {
-	v, err := time.ParseDuration(val)
-	*i.v = v
-	if err != nil {
-		return fmt.Errorf("bad value for duration flag")
-	}
-	return i.Check(val)
-}
-
-func (i *durationValue) Get() interface{} { return *i.v }
-
-func (i *durationValue) String() string {
-	if i == nil || i.v == nil {
-		return time.Duration(0).String()
-	}
-	return i.v.String()
-}
-
-func (s *durationValue) Predict(prefix string) []string {
-	if s.Predictor != nil {
-		return s.Predictor.Predict(prefix)
-	}
-	return []string{""}
-}

compflag/flags.go

@@ -0,0 +1,259 @@
+package compflag
+
+import (
+	"flag"
+	"fmt"
+	"time"
+
+	"github.com/posener/complete/v2/predict"
+)
+
+// Code auto generated with `go run ./gen`. DO NOT EDIT
+
+//go:generate go run ./gen
+
+// String if a flag function for a flag of type string.
+func String(name string, value string, usage string, options ...predict.Option) *string {
+	return CommandLine.String(name, value, usage, options...)
+}
+
+// StringVar if a flag function for a flag of already exiting variable of type string.
+func StringVar(v *string, name string, value string, usage string, options ...predict.Option) {
+	CommandLine.StringVar(v, name, value, usage, options...)
+}
+
+// Bool if a flag function for a flag of type bool.
+func Bool(name string, value bool, usage string, options ...predict.Option) *bool {
+	return CommandLine.Bool(name, value, usage, options...)
+}
+
+// BoolVar if a flag function for a flag of already exiting variable of type bool.
+func BoolVar(v *bool, name string, value bool, usage string, options ...predict.Option) {
+	CommandLine.BoolVar(v, name, value, usage, options...)
+}
+
+// Int if a flag function for a flag of type int.
+func Int(name string, value int, usage string, options ...predict.Option) *int {
+	return CommandLine.Int(name, value, usage, options...)
+}
+
+// IntVar if a flag function for a flag of already exiting variable of type int.
+func IntVar(v *int, name string, value int, usage string, options ...predict.Option) {
+	CommandLine.IntVar(v, name, value, usage, options...)
+}
+
+// Duration if a flag function for a flag of type time.Duration.
+func Duration(name string, value time.Duration, usage string, options ...predict.Option) *time.Duration {
+	return CommandLine.Duration(name, value, usage, options...)
+}
+
+// DurationVar if a flag function for a flag of already exiting variable of type time.Duration.
+func DurationVar(v *time.Duration, name string, value time.Duration, usage string, options ...predict.Option) {
+	CommandLine.DurationVar(v, name, value, usage, options...)
+}
+
+// String if a flag function for a flag of type string.
+func (fs *FlagSet) String(name string, value string, usage string, options ...predict.Option) *string {
+	p := new(string)
+	fs.StringVar(p, name, value, usage, options...)
+	return p
+}
+
+// StringVar if a flag function for a flag of already exiting variable of type string.
+func (fs *FlagSet) StringVar(p *string, name string, value string, usage string, options ...predict.Option) {
+	(*flag.FlagSet)(fs).Var(newStringValue(value, p, predict.Options(options...)), name, usage)
+}
+
+// Bool if a flag function for a flag of type bool.
+func (fs *FlagSet) Bool(name string, value bool, usage string, options ...predict.Option) *bool {
+	p := new(bool)
+	fs.BoolVar(p, name, value, usage, options...)
+	return p
+}
+
+// BoolVar if a flag function for a flag of already exiting variable of type bool.
+func (fs *FlagSet) BoolVar(p *bool, name string, value bool, usage string, options ...predict.Option) {
+	(*flag.FlagSet)(fs).Var(newBoolValue(value, p, predict.Options(options...)), name, usage)
+}
+
+// Int if a flag function for a flag of type int.
+func (fs *FlagSet) Int(name string, value int, usage string, options ...predict.Option) *int {
+	p := new(int)
+	fs.IntVar(p, name, value, usage, options...)
+	return p
+}
+
+// IntVar if a flag function for a flag of already exiting variable of type int.
+func (fs *FlagSet) IntVar(p *int, name string, value int, usage string, options ...predict.Option) {
+	(*flag.FlagSet)(fs).Var(newIntValue(value, p, predict.Options(options...)), name, usage)
+}
+
+// Duration if a flag function for a flag of type time.Duration.
+func (fs *FlagSet) Duration(name string, value time.Duration, usage string, options ...predict.Option) *time.Duration {
+	p := new(time.Duration)
+	fs.DurationVar(p, name, value, usage, options...)
+	return p
+}
+
+// DurationVar if a flag function for a flag of already exiting variable of type time.Duration.
+func (fs *FlagSet) DurationVar(p *time.Duration, name string, value time.Duration, usage string, options ...predict.Option) {
+	(*flag.FlagSet)(fs).Var(newDurationValue(value, p, predict.Options(options...)), name, usage)
+}
+
+// ============================================================================================== //
+
+type stringValue struct {
+	v *string
+	predict.Config
+}
+
+func newStringValue(val string, p *string, c predict.Config) *stringValue {
+	*p = val
+	return &stringValue{v: p, Config: c}
+}
+
+func (v *stringValue) Set(val string) error {
+	var err error
+	*v.v, err = parseString(val)
+	if err != nil {
+		return fmt.Errorf("bad value for String flag")
+	}
+	return v.Check(val)
+}
+
+func (v *stringValue) Get() interface{} {
+	return *v.v
+}
+
+func (v *stringValue) String() string {
+	if v == nil || v.v == nil {
+		return ""
+	}
+	return formatString(*v.v)
+}
+
+func (v *stringValue) Predict(prefix string) []string {
+	if v.Predictor != nil {
+		return v.Predictor.Predict(prefix)
+	}
+	return []string{""}
+}
+
+// ============================================================================================== //
+
+type boolValue struct {
+	v *bool
+	predict.Config
+}
+
+func newBoolValue(val bool, p *bool, c predict.Config) *boolValue {
+	*p = val
+	return &boolValue{v: p, Config: c}
+}
+
+func (v *boolValue) Set(val string) error {
+	var err error
+	*v.v, err = parseBool(val)
+	if err != nil {
+		return fmt.Errorf("bad value for Bool flag")
+	}
+	return v.Check(val)
+}
+
+func (v *boolValue) Get() interface{} {
+	return *v.v
+}
+
+func (v *boolValue) String() string {
+	if v == nil || v.v == nil {
+		return ""
+	}
+	return formatBool(*v.v)
+}
+
+func (v *boolValue) IsBoolFlag() bool { return true }
+
+func (v *boolValue) Predict(prefix string) []string {
+	if v.Predictor != nil {
+		return v.Predictor.Predict(prefix)
+	}
+	return predictBool(*v.v, prefix)
+}
+
+// ============================================================================================== //
+
+type intValue struct {
+	v *int
+	predict.Config
+}
+
+func newIntValue(val int, p *int, c predict.Config) *intValue {
+	*p = val
+	return &intValue{v: p, Config: c}
+}
+
+func (v *intValue) Set(val string) error {
+	var err error
+	*v.v, err = parseInt(val)
+	if err != nil {
+		return fmt.Errorf("bad value for Int flag")
+	}
+	return v.Check(val)
+}
+
+func (v *intValue) Get() interface{} {
+	return *v.v
+}
+
+func (v *intValue) String() string {
+	if v == nil || v.v == nil {
+		return ""
+	}
+	return formatInt(*v.v)
+}
+
+func (v *intValue) Predict(prefix string) []string {
+	if v.Predictor != nil {
+		return v.Predictor.Predict(prefix)
+	}
+	return []string{""}
+}
+
+// ============================================================================================== //
+
+type durationValue struct {
+	v *time.Duration
+	predict.Config
+}
+
+func newDurationValue(val time.Duration, p *time.Duration, c predict.Config) *durationValue {
+	*p = val
+	return &durationValue{v: p, Config: c}
+}
+
+func (v *durationValue) Set(val string) error {
+	var err error
+	*v.v, err = parseDuration(val)
+	if err != nil {
+		return fmt.Errorf("bad value for Duration flag")
+	}
+	return v.Check(val)
+}
+
+func (v *durationValue) Get() interface{} {
+	return *v.v
+}
+
+func (v *durationValue) String() string {
+	if v == nil || v.v == nil {
+		return ""
+	}
+	return formatDuration(*v.v)
+}
+
+func (v *durationValue) Predict(prefix string) []string {
+	if v.Predictor != nil {
+		return v.Predictor.Predict(prefix)
+	}
+	return []string{""}
+}

compflag/gen/flags.go.gotmpl

@@ -0,0 +1,83 @@
+package compflag
+
+// Code auto generated with `go run ./gen`. DO NOT EDIT
+
+//go:generate go run ./gen
+
+
+{{ range . }}
+
+// {{ .Name }} if a flag function for a flag of type {{ .Type }}.
+func {{ .Name }}(name string, value {{ .Type }}, usage string, options ...predict.Option) *{{ .Type }} {
+	return CommandLine.{{ .Name }}(name, value, usage, options...)
+}
+
+// {{ .Name }}Var if a flag function for a flag of already exiting variable of type {{ .Type }}.
+func {{ .Name }}Var(v *{{ .Type }}, name string, value {{ .Type }}, usage string, options ...predict.Option) {
+	CommandLine.{{ .Name }}Var(v, name, value, usage, options...)
+}
+
+{{ end }}
+
+{{ range . }}
+
+// {{ .Name }} if a flag function for a flag of type {{ .Type }}.
+func (fs *FlagSet) {{ .Name }}(name string, value {{ .Type }}, usage string, options ...predict.Option) *{{ .Type }} {
+	p := new({{ .Type }})
+	fs.{{.Name}}Var(p, name, value, usage, options...)
+	return p
+}
+
+// {{ .Name }}Var if a flag function for a flag of already exiting variable of type {{ .Type }}.
+func (fs *FlagSet) {{ .Name }}Var(p *{{ .Type }}, name string, value {{ .Type }}, usage string, options ...predict.Option) {
+	(*flag.FlagSet)(fs).Var({{ .NewInternalTypeFuncName }}(value, p, predict.Options(options...)), name, usage)
+}
+
+{{ end }}
+
+{{ range . }}
+
+// ============================================================================================== //
+
+type {{ .InternalTypeName }} struct {
+	v *{{ .Type }}
+	predict.Config
+}
+
+func {{ .NewInternalTypeFuncName }}(val {{ .Type }}, p *{{ .Type }}, c predict.Config) *{{ .InternalTypeName }} {
+	*p = val
+	return &{{ .InternalTypeName}} {v: p, Config: c}
+}
+
+func (v *{{ .InternalTypeName }}) Set(val string) error {
+	var err error
+	*v.v, err = parse{{ .Name }}(val)
+	if err != nil {
+		return fmt.Errorf("bad value for {{ .Name }} flag")
+	}
+	return v.Check(val)
+}
+
+func (v *{{ .InternalTypeName }}) Get() interface{} {
+	return *v.v
+}
+
+func (v *{{ .InternalTypeName }}) String() string {
+	if v == nil || v.v == nil {
+		return ""
+	}
+	return format{{ .Name }}(*v.v)
+}
+
+{{ if .IsBool }}
+func (v *{{ .InternalTypeName }}) IsBoolFlag() bool { return true }
+{{ end}}
+
+func (v *{{ .InternalTypeName }}) Predict(prefix string) []string {
+	if v.Predictor != nil {
+		return v.Predictor.Predict(prefix)
+	}
+	return {{ if .CustomPredict }}predict{{ .Name }}(*v.v, prefix){{ else }}[]string{""}{{ end }}
+}
+
+{{ end }}

compflag/gen/main.go

@@ -0,0 +1,67 @@
+// Generates flags.go.
+package main
+
+import (
+	"log"
+	"os"
+	"path/filepath"
+	"strings"
+	"text/template"
+
+	"github.com/posener/script"
+)
+
+const tmplGlob = "gen/*.go.gotmpl"
+
+type flag struct {
+	Name          string
+	Type          string
+	IsBool        bool
+	CustomPredict bool
+}
+
+func (f flag) NewInternalTypeFuncName() string {
+	return "new" + strings.Title(f.InternalTypeName())
+}
+
+func (f flag) InternalTypeName() string {
+	return strings.ToLower(f.Name[:1]) + f.Name[1:] + "Value"
+}
+
+var flags = []flag{
+	{Name: "String", Type: "string"},
+	{Name: "Bool", Type: "bool", IsBool: true, CustomPredict: true},
+	{Name: "Int", Type: "int"},
+	{Name: "Duration", Type: "time.Duration"},
+}
+
+var tmpl = template.Must(template.ParseGlob(tmplGlob))
+
+func main() {
+	for _, t := range tmpl.Templates() {
+		fileName := outFileName(t.Name())
+		f, err := os.Create(fileName)
+		if err != nil {
+			panic(err)
+		}
+		defer f.Close()
+
+		log.Printf("Writing %s", fileName)
+		err = t.Execute(f, flags)
+		if err != nil {
+			panic(err)
+		}
+
+		// Format the file.
+		err = script.ExecHandleStderr(os.Stderr, "goimports", "-w", fileName).ToStdout()
+		if err != nil {
+			panic(err)
+		}
+	}
+}
+
+func outFileName(templateName string) string {
+	name := filepath.Base(templateName)
+	// Remove .gotmpl suffix.
+	return name[:strings.LastIndex(name, ".")]
+}