Add bash implementation of autocomplete and add names helper for command and option sets

command.go

@@ -71,6 +71,13 @@ func (c *Command) Execute(args []string) {
 	if c.isRoot {
 		args = args[1:]
 	}
+	if len(args) > 0 {
+		sc, ok := c.Subcommands.Get(args[0])
+		if ok {
+			sc.Execute(args[1:])
+			return
+		}
+	}
 
 	parser := opt.NewParser(args, c.Opts, false)
 	restArgs, err := parser.Parse()
@@ -80,14 +87,6 @@ func (c *Command) Execute(args []string) {
 		os.Exit(1)
 	}
 
-	if len(restArgs) > 0 {
-		sc, ok := c.Subcommands.Get(restArgs[0])
-		if ok {
-			sc.Execute(restArgs[1:])
-			return
-		}
-	}
-
 	helpOpt, ok := opt.Globals().GetBool("help")
 	if ok && helpOpt.Value() {
 		c.ShowHelp()

completions_bash.go

@@ -9,11 +9,46 @@ import (
 
 func WriteBashCompletions(out io.Writer, rootCmd *Command) error {
 	return bashTpl.Execute(out, map[string]any{
-		"rootCmd":    rootCmd,
-		"globalOpts": opt.Globals(),
+		"RootCmd":    rootCmd,
+		"GlobalOpts": opt.Globals(),
 	})
 }
 
-var bashTpl = template.Must(template.New("bash").Parse(`
-	
+var bashTpl = template.Must(template.New("bash").Funcs(tplFuncs).Parse(`
+{{- $rootCmd := .RootCmd -}}
+{{- $progName := $rootCmd.Name -}}
+{{- $varName := under $rootCmd.Name -}}
+
+{{- define "cmd" }}
+  {{ $currIdx := .Index }}
+  {{ $nextIdx := inc .Index }}
+  "{{ .Cmd.Name }}")
+	case ${COMP_WORDS[{{ $currIdx }}]} in
+		{{ range .Cmd.Subcommands -}}
+		{{ template "cmd" (map "Cmd" . "Index" $nextIdx) -}}
+		{{ end }}
+		*)
+			COMPREPLY=($(compgen -W "{{ join .Cmd.Subcommands.Names " " }} {{ join .Cmd.Opts.Names " "  }}" -- $curr))
+	esac
+  ;;
+{{ end -}}
+
+_{{$varName}}_completions()
+{
+	local curr prev
+	COMPREPLY=()
+	curr=${COMP_WORDS[COMP_CWORD]}
+	prev=${COMP_WORDS[COMP_CWORD-1]}
+
+    case ${COMP_WORDS[1]} in
+		{{ range .RootCmd.Subcommands -}}
+		{{ template "cmd" (map "Cmd" . "Index" 2) -}}
+		{{ end }}
+
+		*)
+		    COMPREPLY=($(compgen -W "{{ join .RootCmd.Subcommands.Names " " }} {{ join .RootCmd.Opts.Names " "  }}" -- $curr))
+	esac
+}
+
+complete -F _{{$varName}}_completions {{$progName}}
 `))

completions_fish.go

@@ -19,7 +19,7 @@ var fishTpl = template.Must(template.New("fish").Funcs(tplFuncs).Parse(`
 {{- $rootCmd := .RootCmd -}}
 {{- $progName := $rootCmd.Name -}}
 {{- $varName := under $rootCmd.Name -}}
-set -l commands {{- range $rootCmd.Subcommands }} {{ .Name }}{{ end }}
+set -l commands {{ join $rootCmd.Subcommands.Names " " }}
 
 function __fish_{{ $varName }}_needs_command
 	set -l cmd (commandline -opc)
@@ -75,7 +75,7 @@ complete -f -c {{ $progName }} -n "__fish_{{ $varName }}_using_command {{.Cmd.Pa
 {{ end -}}
 
 {{ if gt (len .Cmd.Subcommands) 0  }}
-set -l {{ $varPrefix }}commands {{- range .Cmd.Subcommands }} {{ .Name }}{{ end -}}
+set -l {{ $varPrefix }}commands {{ join .Cmd.Subcommands.Names " " }}
 {{ $cmdName := .Cmd.Name }}
 {{- range .Cmd.Subcommands }}
 {{- template "cmd" (map "Cmd" . "ProgName" $progName "VarName" $varName) -}}

opt/set.go

@@ -33,6 +33,16 @@ func (s Set) Get(name string) (Option, bool) {
 	return nil, false
 }
 
+func (s Set) Names() []string {
+	names := []string{}
+	for _, o := range s {
+		names = append(names, "--"+o.Name())
+		names = append(names, "-"+o.ShortName())
+	}
+	return names
+
+}
+
 func (s Set) GetByLongName(longName string) (Option, bool) {
 	for _, o := range s {
 		if o.Name() == longName {

set.go

@@ -35,6 +35,15 @@ func (s Set) MaxNameWidth() int {
 	return max
 }
 
+func (s Set) Names() []string {
+	names := make([]string, 0, len(s))
+	for _, c := range s {
+		names = append(names, c.Name)
+		names = append(names, c.Aliases...)
+	}
+	return names
+}
+
 func (s Set) Len() int {
 	return len(s)
 }

tpl_funcs.go

@@ -8,9 +8,11 @@ import (
 
 var tplFuncs = template.FuncMap{
 	"map":       tplMap,
+	"cat":       tplCat,
 	"join":      tplJoin,
 	"under":     tplUnder,
 	"varPrefix": tplVarPrefix,
+	"inc":       tplInc,
 }
 
 func tplMap(vals ...any) (map[string]any, error) {
@@ -25,10 +27,14 @@ func tplMap(vals ...any) (map[string]any, error) {
 	return m, nil
 }
 
-func tplJoin(strs ...string) string {
+func tplCat(strs ...string) string {
 	return strings.Join(strs, "")
 }
 
+func tplJoin(strs []string, sep string) string {
+	return strings.Join(strs, sep)
+}
+
 func tplUnder(s string) string {
 	return strings.ToLower(strings.ReplaceAll(strings.ReplaceAll(s, " ", "_"), "-", "_"))
 }
@@ -40,3 +46,7 @@ func tplVarPrefix(s string) string {
 
 	return tplUnder(s) + "_"
 }
+
+func tplInc(i int) int {
+	return i + 1
+}