Release v0.3.0

- Implement the completion script for PowerShell
- Add global options to zsh completion script

cmd/example-cmd.go

@@ -0,0 +1,39 @@
+package main
+
+import (
+	"fmt"
+	"os"
+
+	"go.fifitido.net/cmd"
+	"go.fifitido.net/cmd/opt"
+)
+
+var (
+	so = opt.String("string", "s", "", "example string option")
+	io = opt.Int("int", "i", 0, "example int option")
+	fo = opt.Float("float", "f", 0, "example float option")
+	bo = opt.Bool("bool", "b", false, "example bool option")
+)
+
+var root = cmd.NewRoot(
+	"example-cmd",
+	cmd.WithShortDescription("Example command"),
+	cmd.WithLongDescription(`An example command to show how to use go.fifitido.net/cmd
+
+this example is just a simple hello world program to show
+the basics of the library.`),
+	cmd.WithArgument("name", false),
+	cmd.WithSubcommand(cmd.CompletionsSubcommand()),
+	cmd.WithOptions(so, io, fo, bo),
+	cmd.WithRunFunc(func(args []string) {
+		if len(args) == 0 {
+			fmt.Println("Hello World!")
+		} else {
+			fmt.Printf("Hello %s!\n", args[0])
+		}
+	}),
+)
+
+func main() {
+	root.Execute(os.Args)
+}

command.go

@@ -3,32 +3,32 @@ package cmd
 import (
 	"fmt"
 	"os"
-	"path/filepath"
 
-	"go.fifitido.net/cmd/opts"
+	"go.fifitido.net/cmd/opt"
 )
 
 type Command struct {
-	name             string
-	shortDescription string
-	longDescription  string
-	aliases          []string
-	arguments        []*Argument
-	opts             opts.Set
-	subcommands      Set
-	parent           *Command
+	Name             string
+	version          string
+	ShortDescription string
+	LongDescription  string
+	Aliases          []string
+	Args             []*Argument
+	Opts             opt.Set
+	Subcommands      Set
+	Parent           *Command
 	run              func(args []string)
 	isRoot           bool
 }
 
-func NewRoot(options ...Option) *Command {
-	cmd := &Command{isRoot: true}
+func NewRoot(name string, version string, options ...Option) *Command {
+	cmd := &Command{Name: name, version: version, isRoot: true}
 	cmd.ApplyOptions(options...)
 	return cmd
 }
 
 func New(name string, options ...Option) *Command {
-	cmd := &Command{name: name}
+	cmd := &Command{Name: name}
 	cmd.ApplyOptions(options...)
 	return cmd
 }
@@ -44,15 +44,24 @@ func (c *Command) Root() *Command {
 		return c
 	}
 
-	return c.parent.Root()
+	return c.Parent.Root()
+}
+
+func (c *Command) IsRoot() bool {
+	return c.isRoot
 }
 
 func (c *Command) CommandPath() string {
-	if c.parent == nil {
-		return filepath.Base(os.Args[0])
+	if c.Parent == nil {
+		return ""
 	}
 
-	return c.parent.CommandPath() + " " + c.name
+	parentPath := c.Parent.CommandPath()
+	if parentPath == "" {
+		return c.Name
+	}
+
+	return c.Parent.CommandPath() + " " + c.Name
 }
 
 func (c *Command) CanRun() bool {
@@ -67,8 +76,15 @@ 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 := opts.NewParser(args, c.opts, false)
+	parser := opt.NewParser(args, c.Opts, false)
 	restArgs, err := parser.Parse()
 	if err != nil {
 		fmt.Println(err.Error())
@@ -76,15 +92,13 @@ 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
-		}
+	versionOpt, ok := opt.Globals().GetBool("version")
+	if ok && versionOpt.Value() {
+		c.ShowVersion()
+		return
 	}
 
-	helpOpt, ok := opts.Globals().GetBool("help")
+	helpOpt, ok := opt.Globals().GetBool("help")
 	if ok && helpOpt.Value() {
 		c.ShowHelp()
 		return
@@ -97,3 +111,8 @@ func (c *Command) Execute(args []string) {
 
 	c.ShowHelp()
 }
+
+func (c *Command) ShowVersion() {
+	rootName := c.Root().Name
+	fmt.Printf("%s %s\n", rootName, c.version)
+}

completions.go

@@ -0,0 +1,124 @@
+package cmd
+
+import (
+	"io"
+	"os"
+
+	"go.fifitido.net/cmd/opt"
+)
+
+var outputFileOption = opt.String("output", "o", "", "The file to output the completions to")
+
+func CompletionsSubcommand() *Command {
+	cmd := New(
+		"completions",
+		WithShortDescription("Generate shell completions"),
+		WithLongDescription("Generate shell completions"),
+	)
+
+	registerBashCompletions(cmd)
+	registerFishCompletions(cmd)
+	registerPowerShellCompletions(cmd)
+	registerZsgCompletions(cmd)
+
+	return cmd
+}
+
+func getCompletionsOut() io.Writer {
+	outputFile := outputFileOption.Value()
+
+	if outputFile != "" {
+		var err error
+		out, err := os.OpenFile(outputFile, os.O_WRONLY|os.O_CREATE, 0644)
+		if err != nil {
+			panic(err)
+		}
+		return out
+	}
+
+	return os.Stdout
+}
+
+func registerBashCompletions(parent *Command) *Command {
+	return New(
+		"bash",
+		WithShortDescription("Generate bash completions"),
+		WithLongDescription("Generate bash completions"),
+		WithOptions(outputFileOption),
+		WithParent(parent),
+		WithRunFunc(func(args []string) {
+			out := getCompletionsOut()
+
+			if fc, ok := out.(io.Closer); ok {
+				defer fc.Close()
+			}
+
+			if err := WriteBashCompletions(out, parent.Root()); err != nil {
+				panic(err)
+			}
+		}),
+	)
+}
+
+func registerFishCompletions(parent *Command) *Command {
+	return New(
+		"fish",
+		WithShortDescription("Generate fish completions"),
+		WithLongDescription("Generate fish completions"),
+		WithOptions(outputFileOption),
+		WithParent(parent),
+		WithRunFunc(func(args []string) {
+			out := getCompletionsOut()
+
+			if fc, ok := out.(io.Closer); ok {
+				defer fc.Close()
+			}
+
+			if err := WriteFishCompletions(out, parent.Root()); err != nil {
+				panic(err)
+			}
+		}),
+	)
+}
+
+func registerPowerShellCompletions(parent *Command) *Command {
+	return New(
+		"powershell",
+		WithShortDescription("Generate powershell completions"),
+		WithLongDescription("Generate powershell completions"),
+		WithOptions(outputFileOption),
+		WithParent(parent),
+		WithRunFunc(func(args []string) {
+			out := getCompletionsOut()
+
+			if fc, ok := out.(io.Closer); ok {
+				defer fc.Close()
+			}
+
+			if err := WritePowerShellCompletions(out, parent.Root()); err != nil {
+				panic(err)
+			}
+		}),
+	)
+}
+
+func registerZsgCompletions(parent *Command) *Command {
+	return New(
+		"zsh",
+		WithShortDescription("Generate zsh completions"),
+		WithLongDescription("Generate zsh completions"),
+		WithOptions(outputFileOption),
+		WithParent(parent),
+		WithRunFunc(func(args []string) {
+			out := getCompletionsOut()
+
+			if fc, ok := out.(io.Closer); ok {
+				defer fc.Close()
+			}
+
+			if err := WriteZshCompletions(out, parent.Root()); err != nil {
+				panic(err)
+			}
+		}),
+	)
+}

completions_bash.go

@@ -0,0 +1,58 @@
+package cmd
+
+import (
+	"io"
+	"text/template"
+
+	"go.fifitido.net/cmd/opt"
+)
+
+func WriteBashCompletions(out io.Writer, rootCmd *Command) error {
+	return bashTpl.Execute(out, map[string]any{
+		"RootCmd":    rootCmd,
+		"GlobalOpts": opt.Globals(),
+	})
+}
+
+// TODO: Add --option|--other-option...) to return nothing for options that require a value
+// TODO: Add descriptions to completions using https://stackoverflow.com/a/10130007
+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 -}}
+{{- $indentSize := mult $currIdx 2 -}}
+{{ indent $indentSize }}"{{ .Cmd.Name }}")
+{{ indent $indentSize }}  case ${COMP_WORDS[{{ $currIdx }}]} in
+{{ indent $indentSize }}	{{ range .Cmd.Subcommands -}}
+{{ indent $indentSize }}	{{ template "cmd" (map "Cmd" . "Index" $nextIdx) -}}
+{{ indent $indentSize }}	{{ end }}
+{{ indent $indentSize }}    *)
+{{ indent $indentSize }}      COMPREPLY=($(compgen -W "{{ join .Cmd.Subcommands.Names " " }} {{ join .Cmd.Opts.Names " "  }}" -- $curr))
+{{ indent $indentSize }}    ;;
+{{ indent $indentSize }}  esac
+{{ indent $indentSize }};; # {{ .Cmd.Name }}
+{{- end -}}
+
+_{{$varName}}_completions()
+{
+  COMPREPLY=()
+
+  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 " "  }}" -- $curr))
+    ;;
+  esac
+
+  # Global Options
+  COMPREPLY+=($(compgen -W "{{ join .GlobalOpts.Names " " }}" -- $curr))
+}
+
+complete -F _{{$varName}}_completions {{$progName}}
+`))

completions_fish.go

@@ -0,0 +1,100 @@
+package cmd
+
+import (
+	"io"
+	"text/template"
+
+	"go.fifitido.net/cmd/opt"
+)
+
+func WriteFishCompletions(out io.Writer, rootCmd *Command) error {
+	return fishTpl.Execute(out, map[string]any{
+		"RootCmd":    rootCmd,
+		"GlobalOpts": opt.Globals(),
+	})
+}
+
+// TODO: Fix fish infinitely completing last command at the end of the command chain
+var fishTpl = template.Must(template.New("fish").Funcs(tplFuncs).Parse(`
+{{- $rootCmd := .RootCmd -}}
+{{- $progName := $rootCmd.Name -}}
+{{- $varName := under $rootCmd.Name -}}
+set -l commands {{ join $rootCmd.Subcommands.Names " " }}
+
+function __fish_{{ $varName }}_needs_command
+	set -l cmd (commandline -opc)
+	if test (count $cmd) -eq 1
+		return 0
+	end
+	return 1
+end
+
+function __fish_{{ $varName }}_using_command
+	set -l cmd (commandline -opc)
+	set -l cnt (count $argv)
+	if test (count $cmd) -gt $cnt
+		for i in (seq 1 $cnt);
+			if test $argv[$i] != $cmd[(math $i + 1)]
+				return 1
+			end
+		end
+		return 0
+	end
+	return 1
+end
+
+{{/* Option template */ -}}
+{{ define "opt" }}
+{{ $progName := .ProgName -}}
+{{- $varName := .VarName -}}
+complete -c {{ $progName }}
+{{- if ne .Opt.ShortName "" }} -s {{ .Opt.ShortName }} {{ end -}}
+{{- if ne .Opt.Name "" }} -l {{ .Opt.Name }} {{ end -}} 
+{{- if .Cmd }} {{- if ne .Cmd.CommandPath "" -}}
+-n "__fish_{{ $varName }}_using_command {{.Cmd.CommandPath}}" {{ else -}}
+-n "__fish_{{ $varName }}_needs_command" {{ end -}}{{- end -}}
+-d '{{ .Opt.Description }}'
+{{- end }}
+
+{{- /* Command template */ -}}
+{{ define "cmd" }}
+{{ $progName := .ProgName -}}
+{{- $varName := .VarName -}}
+{{- $cmd := .Cmd -}}
+{{- $parentVarPrefix := varPrefix .Cmd.Parent.CommandPath -}}
+{{- $varPrefix := varPrefix .Cmd.CommandPath -}}
+
+{{- if eq .Cmd.Parent.CommandPath "" -}}
+complete -f -c {{ $progName }} -n "__fish_{{ $varName }}_needs_command" -a {{ .Cmd.Name }} -d "{{ .Cmd.ShortDescription }}"
+{{- else -}}
+complete -f -c {{ $progName }} -n "__fish_{{ $varName }}_using_command {{.Cmd.Parent.CommandPath}}" -a {{ .Cmd.Name }} -d "{{ .Cmd.ShortDescription }}"
+{{- end -}}
+
+{{- range .Cmd.Opts }}
+{{- template "opt" (map "Opt" . "ProgName" $progName "VarName" $varName "Cmd" $cmd) -}}
+{{ end -}}
+
+{{ if gt (len .Cmd.Subcommands) 0  }}
+set -l {{ $varPrefix }}commands {{ join .Cmd.Subcommands.Names " " }}
+{{ $cmdName := .Cmd.Name }}
+{{- range .Cmd.Subcommands }}
+{{- template "cmd" (map "Cmd" . "ProgName" $progName "VarName" $varName) -}}
+{{ end -}}
+{{- end -}}
+{{ end }}
+
+{{- /* Top-level commands */ -}}
+{{ range $rootCmd.Subcommands }}
+{{- template "cmd" (map "Cmd" . "ProgName" $progName "VarName" $varName) -}}
+{{ end }}
+
+{{- /* Root command options */ -}}
+{{ range $rootCmd.Opts }}
+{{- template "opt" (map "Opt" . "ProgName" $progName "VarName" $varName "Cmd" $rootCmd) -}}
+{{ end }}
+
+{{- /* Global options */ -}}
+{{ range .GlobalOpts }}
+{{- template "opt" (map "Opt" . "ProgName" $progName "VarName" $varName) -}}
+{{ end }}
+`))

completions_powershell.go

@@ -0,0 +1,90 @@
+package cmd
+
+import (
+	"io"
+	"text/template"
+
+	"go.fifitido.net/cmd/opt"
+)
+
+func WritePowerShellCompletions(out io.Writer, rootCmd *Command) error {
+	return powerShellTpl.Execute(out, map[string]any{
+		"RootCmd":    rootCmd,
+		"GlobalOpts": opt.Globals(),
+	})
+}
+
+var powerShellTpl = template.Must(template.New("PowerShell").Funcs(tplFuncs).Parse(`
+{{- $rootCmd := .RootCmd -}}
+{{- $progName := $rootCmd.Name -}}
+{{- $varName := $rootCmd.Name | camel -}}
+
+{{- define "cmd" -}}
+{{- $progName := .ProgName -}}
+{{- if .Cmd.IsRoot }}
+{{- /**/}}            '{{ $progName }}' {
+{{- else }}
+{{- /**/}}            '{{ $progName }};{{ join (split .Cmd.CommandPath " ") ";" }}' {
+{{- end -}}
+{{- range .Cmd.Opts -}}
+{{ if ne .Name "" }}
+                [CompletionResult]::new('--{{ .Name }}', '{{ .Name }}', [CompletionResultType]::ParameterName, '{{ .Description }}')
+{{- end -}}
+{{- if ne .ShortName "" }}
+                [CompletionResult]::new('-{{ .ShortName }}', '{{ .ShortName }}', [CompletionResultType]::ParameterName, '{{ .Description }}')
+{{- end -}}
+{{- end }}
+{{- range .Cmd.Subcommands }}
+                [CompletionResult]::new('{{ .Name }}', '{{ .Name }}', [CompletionResultType]::ParameterValue, '{{ .ShortDescription }}')
+{{- end }}
+                break;
+            }
+{{- range .Cmd.Subcommands }}
+{{ template "cmd" (map "Cmd" . "ProgName" $progName) }}
+{{- end -}}
+{{- end -}}
+using namespace System.Management.Automation
+using namespace System.Management.Automation.Language
+
+[scriptblock]$__{{ $varName }}CompleterBlock = {
+    param(
+        $wordToComplete,
+        $commandAst,
+        $cursorPosition
+    )
+
+    $commandElements
+    $command = @(
+        '{{ $progName }}'
+        for ($i = 1; $i -lt $commandElements.Count; $i++) {
+            $element = $commandElements[$i]
+            if ($element -isnot [StringConstantExpressionAst] -or
+                $element.StringConstantType -ne [StringConstantType]::BareWord -or
+                $element.Value.StartsWith('-') -or
+                $element.Value -eq $wordToComplete) {
+                break
+            }
+            $element.Value
+        }
+    ) -join ';'
+
+    $completions = @(
+        switch ($command) {
+{{ template "cmd" (map "Cmd" $rootCmd "ProgName" $progName) }}
+        }
+{{- range .GlobalOpts -}}
+{{- if ne .Name "" }}
+        [CompletionResult]::new('--{{ .Name }}', '{{ .Name }}', [CompletionResultType]::ParameterName, '{{ .Description }}')
+{{- end -}}
+{{- if ne .ShortName "" }}
+        [CompletionResult]::new('-{{ .ShortName }}', '{{ .ShortName }}', [CompletionResultType]::ParameterName, '{{ .Description }}')
+{{- end -}}
+{{- end -}}
+    )
+
+    $completions.Where{ $_.CompletionText -like "$wordToComplete*" } |
+        Sort-Object -Property ListItemText
+}
+
+Register-ArgumentCompleter -CommandName {{ $progName }} -ScriptBlock $__{{ $varName }}CompleterBlock
+`))

completions_zsh.go

@@ -0,0 +1,85 @@
+package cmd
+
+import (
+	"io"
+	"text/template"
+
+	"go.fifitido.net/cmd/opt"
+)
+
+func WriteZshCompletions(out io.Writer, rootCmd *Command) error {
+	return zshTpl.Execute(out, map[string]any{
+		"RootCmd":    rootCmd,
+		"GlobalOpts": opt.Globals(),
+	})
+}
+
+// TODO: Fix indentation and other spacing
+var zshTpl = template.Must(template.New("zsh").Funcs(tplFuncs).Parse(`
+{{- $rootCmd := .RootCmd -}}
+{{- $progName := $rootCmd.Name -}}
+{{- $varName := under $rootCmd.Name -}}
+
+{{- define "cmd" }}
+{{- $varPrefix := varPrefix .Cmd.CommandPath -}}
+{{- if not .Cmd.IsRoot}}
+{{ .Cmd.Name }})
+{{ end -}}
+  {{ if gt (len .Cmd.Subcommands) 0 -}}
+  local -a {{ $varPrefix }}commands
+  {{ $varPrefix }}commands=(
+    {{- range .Cmd.Subcommands}}
+    '{{ .Name }}:{{ .ShortDescription }}'
+    {{- end }}
+  )
+  {{ end }}
+
+  {{- if or (gt (len .Cmd.Opts) 0) (gt (len .Cmd.Subcommands) 0) -}}
+  _arguments
+  {{- end -}}
+  {{- range .Cmd.Opts -}}
+    {{- if ne .Name ""}} \
+    '--{{ .Name }}[{{ .Description }}]'
+    {{- end }}
+    {{- if ne .ShortName ""}} \
+    '-{{ .ShortName }}[{{ .Description }}]'
+    {{- end }}
+  {{- end }}
+  {{- if gt (len .Cmd.Subcommands) 0 -}}
+    {{ " " }}\
+    '1: :{_describe 'command' {{ $varPrefix }}commands}' \
+    '*:: :->args'
+  
+  case $state in
+    args)
+      case $words[1] in
+        {{- range .Cmd.Subcommands }}
+          {{ template "cmd" (map "Cmd" .) }}
+        {{- end }}
+      esac
+      ;;
+  esac
+  {{- end }}
+{{- if not .Cmd.IsRoot}}
+  ;;
+{{ end }}
+{{ end -}}
+
+function _{{ $varName }} {
+  {{ template "cmd" (map "Cmd" .RootCmd) -}}
+
+  {{- if gt (len .GlobalOpts) 0 }}
+  _arguments
+    {{- range .GlobalOpts -}}
+      {{- if ne .Name ""}} \
+      '--{{ .Name }}[{{ .Description }}]'
+      {{- end }}
+      {{- if ne .ShortName ""}} \
+      '-{{ .ShortName }}[{{ .Description }}]'
+      {{- end }}
+    {{- end }}
+  {{- end }}
+}
+
+compdef _{{ $varName }} {{ $progName }}
+`))

examples/hello-world/cmd/main.go

@@ -8,6 +8,7 @@ import (
 )
 
 var root = cmd.NewRoot(
+	"hello-world",
 	cmd.WithShortDescription("Example command"),
 	cmd.WithLongDescription(`An example command to show how to use go.fifitido.net/cmd
 

examples/hello-world/go.mod

@@ -2,4 +2,4 @@ module go.fifitido.net/cmd/examples/hello-world
 
 go 1.21.3
 
-require go.fifitido.net/cmd v0.0.0-20231110055906-31e40ecc826a
+require go.fifitido.net/cmd v0.2.0

examples/hello-world/go.sum

@@ -1,6 +1,2 @@
-go.fifitido.net/cmd v0.0.0-20231110043437-c32ce2efcd5f h1:v+sjO+t6cGEtDhStOnuypYBrkOMO4suiDVxL93rOUCs=
-go.fifitido.net/cmd v0.0.0-20231110043437-c32ce2efcd5f/go.mod h1:8SaDxCG1m6WwShUlZApSbNleCvV7oTfqZIyYu4aAqO0=
-go.fifitido.net/cmd v0.0.0-20231110054944-def39983fdfa h1:Z62sZG2rnKMqa0jI+WD1t8vO9ESQsQa4j6ad9OFeREM=
-go.fifitido.net/cmd v0.0.0-20231110054944-def39983fdfa/go.mod h1:8SaDxCG1m6WwShUlZApSbNleCvV7oTfqZIyYu4aAqO0=
-go.fifitido.net/cmd v0.0.0-20231110055906-31e40ecc826a h1:qT/xBA3vcVJYgaPoei70yRlLoB1CdaL3FPzi0kZ+JF0=
-go.fifitido.net/cmd v0.0.0-20231110055906-31e40ecc826a/go.mod h1:8SaDxCG1m6WwShUlZApSbNleCvV7oTfqZIyYu4aAqO0=
+go.fifitido.net/cmd v0.2.0 h1:QEq4Gbts4DjnzXLwxV4xaSI3kleVXmtvSFcuOGjBGqc=
+go.fifitido.net/cmd v0.2.0/go.mod h1:8SaDxCG1m6WwShUlZApSbNleCvV7oTfqZIyYu4aAqO0=

go.mod

@@ -1,3 +1,5 @@
 module go.fifitido.net/cmd
 
 go 1.21.3
+
+require github.com/iancoleman/strcase v0.3.0

go.sum

@@ -0,0 +1,2 @@
+github.com/iancoleman/strcase v0.3.0 h1:nTXanmYxhfFAMjZL34Ov6gkzEsSJZ5DbhxWjvSASxEI=
+github.com/iancoleman/strcase v0.3.0/go.mod h1:iwCmte+B7n89clKwxIoIXy/HfoL7AsD47ZCWhYzw7ho=

help.go

@@ -2,29 +2,40 @@ package cmd
 
 import (
 	"fmt"
+	"strings"
 
-	"go.fifitido.net/cmd/opts"
+	"go.fifitido.net/cmd/opt"
 )
 
 func (c *Command) ShowHelp() {
 	cmdPath := c.CommandPath()
+	binaryName := c.Root().Name
 
-	fmt.Println(c.longDescription)
+	fmt.Println(c.LongDescription)
 	fmt.Println()
 	fmt.Println("Usage: ")
-	fmt.Printf("  %s ", cmdPath)
+	fmt.Printf("  %s %s ", binaryName, cmdPath)
 
-	if len(c.subcommands) > 0 {
+	if len(c.Subcommands) > 0 {
 		if c.CanRun() {
 			fmt.Print("[command] ")
 		} else {
 			fmt.Print("<command> ")
 		}
 	}
+	fmt.Print("[options]")
+	if len(c.Args) > 0 {
+		for _, a := range c.Args {
+			if a.Required {
+				fmt.Print(" <" + a.Name + ">")
+			} else {
+				fmt.Print(" [" + a.Name + "]")
+			}
+		}
+	}
+	fmt.Println()
 
-	fmt.Println("[options]")
-
-	if len(c.subcommands) > 0 {
+	if len(c.Subcommands) > 0 {
 		fmt.Println()
 
 		if c.isRoot {
@@ -33,31 +44,34 @@ func (c *Command) ShowHelp() {
 			fmt.Println("Available subcommands:")
 		}
 
-		for _, s := range c.subcommands {
-			fmt.Println("  " + s.name + "    " + s.shortDescription)
+		paddedWidth := c.Subcommands.MaxWidth()
+		for _, s := range c.Subcommands {
+			spaceSize := 2 + paddedWidth - len(s.Name)
+			fmt.Println("  " + s.Name + strings.Repeat(" ", spaceSize) + s.ShortDescription)
 		}
 	}
 
-	fmt.Println()
-	fmt.Println("Available options:")
-
-	paddedWidth := c.opts.MaxWidth()
-	for _, f := range c.opts {
-		fmt.Println("  " + opts.HelpLine(f, paddedWidth))
+	if len(c.Opts) > 0 {
+		fmt.Println()
+		fmt.Println("Available options:")
+		paddedWidth := c.Opts.MaxWidth()
+		for _, f := range c.Opts {
+			fmt.Println("  " + opt.HelpLine(f, paddedWidth))
+		}
 	}
 
-	globalOpts := opts.Globals()
+	globalOpts := opt.Globals()
 	if len(globalOpts) > 0 {
-		paddedWidth = globalOpts.MaxWidth()
 		fmt.Println()
 		fmt.Println("Global options:")
+		paddedWidth := globalOpts.MaxWidth()
 		for _, f := range globalOpts {
-			fmt.Println("  " + opts.HelpLine(f, paddedWidth))
+			fmt.Println("  " + opt.HelpLine(f, paddedWidth))
 		}
 	}
 
-	if len(c.subcommands) > 0 {
+	if len(c.Subcommands) > 0 {
 		fmt.Println()
-		fmt.Printf("Run '%s <command> --help' for more information about a command.\n", c.Root().CommandPath())
+		fmt.Printf("Run '%s <command> --help' for more information about a command.\n", binaryName)
 	}
 }

opt/bool.go

@@ -1,4 +1,4 @@
-package opts
+package opt
 
 import (
 	"strconv"

opt/float.go

@@ -1,4 +1,4 @@
-package opts
+package opt
 
 import "strconv"
 

opt/global.go

@@ -1,4 +1,4 @@
-package opts
+package opt
 
 var globalOpts = Set{
 	Bool("help", "h", false, "Show the help menu"),

opt/int.go

@@ -1,4 +1,4 @@
-package opts
+package opt
 
 import "strconv"
 

opt/option.go

@@ -1,4 +1,4 @@
-package opts
+package opt
 
 import "fmt"
 

opt/parser.go

@@ -1,4 +1,4 @@
-package opts
+package opt
 
 import (
 	"errors"

opt/parser_test.go

@@ -1,15 +1,15 @@
-package opts_test
+package opt_test
 
 import (
 	"testing"
 
-	"go.fifitido.net/cmd/opts"
+	"go.fifitido.net/cmd/opt"
 )
 
 func TestParseUnknownLongOption(t *testing.T) {
-	set := opts.Set{}
+	set := opt.Set{}
 	args := []string{"--unknown"}
-	parser := opts.NewParser(args, set, false)
+	parser := opt.NewParser(args, set, false)
 	_, err := parser.Parse()
 	if err == nil {
 		t.Error("Expected error")
@@ -19,9 +19,9 @@ func TestParseUnknownLongOption(t *testing.T) {
 }
 
 func TestParseUnknownShortOption(t *testing.T) {
-	set := opts.Set{}
+	set := opt.Set{}
 	args := []string{"-u"}
-	parser := opts.NewParser(args, set, false)
+	parser := opt.NewParser(args, set, false)
 	_, err := parser.Parse()
 	if err == nil {
 		t.Error("Expected error")
@@ -31,12 +31,12 @@ func TestParseUnknownShortOption(t *testing.T) {
 }
 
 func TestParseUnknownShortChainedOption1(t *testing.T) {
-	set := opts.Set{
-		opts.Bool("banana", "b", false, ""),
-		opts.Bool("cucumber", "c", false, ""),
+	set := opt.Set{
+		opt.Bool("banana", "b", false, ""),
+		opt.Bool("cucumber", "c", false, ""),
 	}
 	args := []string{"-abc"}
-	parser := opts.NewParser(args, set, false)
+	parser := opt.NewParser(args, set, false)
 	_, err := parser.Parse()
 	if err == nil {
 		t.Error("Expected error")
@@ -46,12 +46,12 @@ func TestParseUnknownShortChainedOption1(t *testing.T) {
 }
 
 func TestParseUnknownShortChainedOption2(t *testing.T) {
-	set := opts.Set{
-		opts.Bool("apple", "a", false, ""),
-		opts.Bool("cucumber", "c", false, ""),
+	set := opt.Set{
+		opt.Bool("apple", "a", false, ""),
+		opt.Bool("cucumber", "c", false, ""),
 	}
 	args := []string{"-abc"}
-	parser := opts.NewParser(args, set, false)
+	parser := opt.NewParser(args, set, false)
 	_, err := parser.Parse()
 	if err == nil {
 		t.Error("Expected error")
@@ -61,12 +61,12 @@ func TestParseUnknownShortChainedOption2(t *testing.T) {
 }
 
 func TestParseUnknownShortChainedOption3(t *testing.T) {
-	set := opts.Set{
-		opts.Bool("apple", "a", false, ""),
-		opts.Bool("banana", "b", false, ""),
+	set := opt.Set{
+		opt.Bool("apple", "a", false, ""),
+		opt.Bool("banana", "b", false, ""),
 	}
 	args := []string{"-abc"}
-	parser := opts.NewParser(args, set, false)
+	parser := opt.NewParser(args, set, false)
 	_, err := parser.Parse()
 	if err == nil {
 		t.Error("Expected error")
@@ -76,12 +76,12 @@ func TestParseUnknownShortChainedOption3(t *testing.T) {
 }
 
 func TestParseUnchaninableOption(t *testing.T) {
-	set := opts.Set{
-		opts.Bool("apple", "a", false, ""),
-		opts.String("banana", "b", "", ""),
+	set := opt.Set{
+		opt.Bool("apple", "a", false, ""),
+		opt.String("banana", "b", "", ""),
 	}
 	args := []string{"-ab"}
-	parser := opts.NewParser(args, set, false)
+	parser := opt.NewParser(args, set, false)
 	_, err := parser.Parse()
 	if err == nil {
 		t.Error("Expected error")
@@ -91,92 +91,92 @@ func TestParseUnchaninableOption(t *testing.T) {
 }
 
 func TestParseShortOptionWithValueAndNoSpace(t *testing.T) {
-	opt := opts.String("fruit", "f", "", "")
-	set := opts.Set{opt}
+	o := opt.String("fruit", "f", "", "")
+	set := opt.Set{o}
 	args := []string{"-fapple"}
-	parser := opts.NewParser(args, set, false)
+	parser := opt.NewParser(args, set, false)
 	_, err := parser.Parse()
 	if err != nil {
 		t.Errorf("Expected no error, got: %s", err.Error())
 	}
 
-	if opt.Value() != "apple" {
-		t.Errorf("Expected fruit to be 'apple', got: %s", opt.Value())
+	if o.Value() != "apple" {
+		t.Errorf("Expected fruit to be 'apple', got: %s", o.Value())
 	}
 }
 
 func TestParseShortOptionWithValueAndSpace(t *testing.T) {
-	opt := opts.String("fruit", "f", "", "")
-	set := opts.Set{opt}
+	o := opt.String("fruit", "f", "", "")
+	set := opt.Set{o}
 	args := []string{"-f", "apple"}
-	parser := opts.NewParser(args, set, false)
+	parser := opt.NewParser(args, set, false)
 	_, err := parser.Parse()
 	if err != nil {
 		t.Errorf("Expected no error, got: %s", err.Error())
 	}
 
-	if opt.Value() != "apple" {
-		t.Errorf("Expected fruit to be 'apple', got: %s", opt.Value())
+	if o.Value() != "apple" {
+		t.Errorf("Expected fruit to be 'apple', got: %s", o.Value())
 	}
 }
 
 func TestParseShortOptionWithValueAndEqual(t *testing.T) {
-	opt := opts.String("fruit", "f", "", "")
-	set := opts.Set{opt}
+	o := opt.String("fruit", "f", "", "")
+	set := opt.Set{o}
 	args := []string{"-f=apple"}
-	parser := opts.NewParser(args, set, false)
+	parser := opt.NewParser(args, set, false)
 	_, err := parser.Parse()
 	if err != nil {
 		t.Errorf("Expected no error, got: %s", err.Error())
 	}
 
-	if opt.Value() != "apple" {
-		t.Errorf("Expected fruit to be 'apple', got: %s", opt.Value())
+	if o.Value() != "apple" {
+		t.Errorf("Expected fruit to be 'apple', got: %s", o.Value())
 	}
 }
 
 func TestParseLongOptionWithValueAndEqual(t *testing.T) {
-	opt := opts.String("fruit", "f", "", "")
-	set := opts.Set{opt}
+	o := opt.String("fruit", "f", "", "")
+	set := opt.Set{o}
 	args := []string{"--fruit=apple"}
-	parser := opts.NewParser(args, set, false)
+	parser := opt.NewParser(args, set, false)
 	_, err := parser.Parse()
 	if err != nil {
 		t.Errorf("Expected no error, got: %s", err.Error())
 	}
 
-	if opt.Value() != "apple" {
-		t.Errorf("Expected fruit to be 'apple', got: %s", opt.Value())
+	if o.Value() != "apple" {
+		t.Errorf("Expected fruit to be 'apple', got: %s", o.Value())
 	}
 }
 
 func TestParseLongOptionWithValueAndSpace(t *testing.T) {
-	opt := opts.String("fruit", "f", "", "")
-	set := opts.Set{opt}
+	o := opt.String("fruit", "f", "", "")
+	set := opt.Set{o}
 	args := []string{"--fruit", "apple"}
-	parser := opts.NewParser(args, set, false)
+	parser := opt.NewParser(args, set, false)
 	_, err := parser.Parse()
 	if err != nil {
 		t.Errorf("Expected no error, got: %s", err.Error())
 	}
 
-	if opt.Value() != "apple" {
-		t.Errorf("Expected fruit to be 'apple', got: %s", opt.Value())
+	if o.Value() != "apple" {
+		t.Errorf("Expected fruit to be 'apple', got: %s", o.Value())
 	}
 }
 
 func TestParseOptionTerminator(t *testing.T) {
-	opt := opts.String("fruit", "f", "banana", "")
-	set := opts.Set{opt}
+	o := opt.String("fruit", "f", "banana", "")
+	set := opt.Set{o}
 	args := []string{"--fruit", "apple", "--", "hello", "world"}
-	parser := opts.NewParser(args, set, false)
+	parser := opt.NewParser(args, set, false)
 	restArgs, err := parser.Parse()
 	if err != nil {
 		t.Errorf("Expected no error, got: %s", err.Error())
 	}
 
-	if opt.Value() != "apple" {
-		t.Errorf("Expected fruit to be 'apple', got: %s", opt.Value())
+	if o.Value() != "apple" {
+		t.Errorf("Expected fruit to be 'apple', got: %s", o.Value())
 	}
 
 	if len(restArgs) != 2 {
@@ -193,9 +193,9 @@ func TestParseOptionTerminator(t *testing.T) {
 }
 
 func TestParseLongOptionIgnoreUnknown(t *testing.T) {
-	set := opts.Set{}
+	set := opt.Set{}
 	args := []string{"--unknown", "hello", "world"}
-	parser := opts.NewParser(args, set, true)
+	parser := opt.NewParser(args, set, true)
 	restArgs, err := parser.Parse()
 	if err != nil {
 		t.Errorf("Expected no error, got: %s", err.Error())
@@ -215,9 +215,9 @@ func TestParseLongOptionIgnoreUnknown(t *testing.T) {
 }
 
 func TestParseShortOptionIgnoreUnknown(t *testing.T) {
-	set := opts.Set{}
+	set := opt.Set{}
 	args := []string{"-q"}
-	parser := opts.NewParser(args, set, true)
+	parser := opt.NewParser(args, set, true)
 
 	_, err := parser.Parse()
 	if err != nil {
@@ -226,12 +226,12 @@ func TestParseShortOptionIgnoreUnknown(t *testing.T) {
 }
 
 func TestParseChainedShortOptionIgnoreUnknown(t *testing.T) {
-	apple := opts.Bool("apple", "a", false, "")
-	banana := opts.Bool("banana", "b", false, "")
-	cucumber := opts.Bool("cucumber", "c", false, "")
-	set := opts.Set{apple, banana, cucumber}
+	apple := opt.Bool("apple", "a", false, "")
+	banana := opt.Bool("banana", "b", false, "")
+	cucumber := opt.Bool("cucumber", "c", false, "")
+	set := opt.Set{apple, banana, cucumber}
 	args := []string{"-adc"}
-	parser := opts.NewParser(args, set, true)
+	parser := opt.NewParser(args, set, true)
 
 	_, err := parser.Parse()
 	if err != nil {
@@ -252,25 +252,25 @@ func TestParseChainedShortOptionIgnoreUnknown(t *testing.T) {
 }
 
 func TestParseSingleDashValue(t *testing.T) {
-	opt := opts.String("fruit", "f", "", "")
-	set := opts.Set{opt}
+	o := opt.String("fruit", "f", "", "")
+	set := opt.Set{o}
 	args := []string{"-f-"}
-	parser := opts.NewParser(args, set, false)
+	parser := opt.NewParser(args, set, false)
 	_, err := parser.Parse()
 	if err != nil {
 		t.Errorf("Expected no error, got: %s", err.Error())
 	}
 
-	if opt.Value() != "-" {
-		t.Errorf("Expected fruit to be '-', got: %s", opt.Value())
+	if o.Value() != "-" {
+		t.Errorf("Expected fruit to be '-', got: %s", o.Value())
 	}
 }
 
 func TestParseLongOptionBadValue(t *testing.T) {
-	opt := opts.Int("fruit", "f", 0, "")
-	set := opts.Set{opt}
+	o := opt.Int("fruit", "f", 0, "")
+	set := opt.Set{o}
 	args := []string{"--fruit=five"}
-	parser := opts.NewParser(args, set, false)
+	parser := opt.NewParser(args, set, false)
 	_, err := parser.Parse()
 	if err == nil {
 		t.Error("Expected error")
@@ -278,10 +278,10 @@ func TestParseLongOptionBadValue(t *testing.T) {
 }
 
 func TestParseShortOptionWithSpaceBadValue(t *testing.T) {
-	opt := opts.Int("fruit", "f", 0, "")
-	set := opts.Set{opt}
+	o := opt.Int("fruit", "f", 0, "")
+	set := opt.Set{o}
 	args := []string{"-f", "five"}
-	parser := opts.NewParser(args, set, false)
+	parser := opt.NewParser(args, set, false)
 	_, err := parser.Parse()
 	if err == nil {
 		t.Error("Expected error")
@@ -289,11 +289,11 @@ func TestParseShortOptionWithSpaceBadValue(t *testing.T) {
 }
 
 func TestParseShortOptionWithoutEqualBadValue(t *testing.T) {
-	optG := opts.Bool("green", "g", false, "")
-	optF := opts.Int("fruit", "f", 0, "")
-	set := opts.Set{optG, optF}
+	og := opt.Bool("green", "g", false, "")
+	of := opt.Int("fruit", "f", 0, "")
+	set := opt.Set{og, of}
 	args := []string{"-ffive"}
-	parser := opts.NewParser(args, set, false)
+	parser := opt.NewParser(args, set, false)
 	_, err := parser.Parse()
 	if err == nil {
 		t.Error("Expected error")
@@ -301,11 +301,11 @@ func TestParseShortOptionWithoutEqualBadValue(t *testing.T) {
 }
 
 func TestParseShortOptionWithEqualBadValue(t *testing.T) {
-	optG := opts.Bool("green", "g", false, "")
-	optF := opts.Int("fruit", "f", 0, "")
-	set := opts.Set{optG, optF}
+	og := opt.Bool("green", "g", false, "")
+	of := opt.Int("fruit", "f", 0, "")
+	set := opt.Set{og, of}
 	args := []string{"-f=five"}
-	parser := opts.NewParser(args, set, false)
+	parser := opt.NewParser(args, set, false)
 	_, err := parser.Parse()
 	if err == nil {
 		t.Error("Expected error")
@@ -313,10 +313,10 @@ func TestParseShortOptionWithEqualBadValue(t *testing.T) {
 }
 
 func TestParseLongOptionMissingValue(t *testing.T) {
-	opt := opts.Float("fruit-price", "f", 0, "")
-	set := opts.Set{opt}
+	o := opt.Float("fruit-price", "f", 0, "")
+	set := opt.Set{o}
 	args := []string{"--fruit-price"}
-	parser := opts.NewParser(args, set, false)
+	parser := opt.NewParser(args, set, false)
 	_, err := parser.Parse()
 	if err == nil {
 		t.Error("Expected error")
@@ -324,10 +324,10 @@ func TestParseLongOptionMissingValue(t *testing.T) {
 }
 
 func TestParseShortOptionMissingValue(t *testing.T) {
-	opt := opts.Float("fruit-price", "f", 0, "")
-	set := opts.Set{opt}
+	o := opt.Float("fruit-price", "f", 0, "")
+	set := opt.Set{o}
 	args := []string{"-f"}
-	parser := opts.NewParser(args, set, false)
+	parser := opt.NewParser(args, set, false)
 	_, err := parser.Parse()
 	if err == nil {
 		t.Error("Expected error")

opt/set.go

@@ -1,4 +1,4 @@
-package opts
+package opt
 
 type Set []Option
 
@@ -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 {

opt/string.go

@@ -1,4 +1,4 @@
-package opts
+package opt
 
 type StringOption struct {
 	name        string

option.go

@@ -1,67 +1,67 @@
 package cmd
 
 import (
-	"go.fifitido.net/cmd/opts"
+	"go.fifitido.net/cmd/opt"
 )
 
 type Option func(*Command)
 
 func WithShortDescription(s string) Option {
 	return func(c *Command) {
-		c.shortDescription = s
+		c.ShortDescription = s
 	}
 }
 
 func WithLongDescription(s string) Option {
 	return func(c *Command) {
-		c.longDescription = s
+		c.LongDescription = s
 	}
 }
 
 func WithArgument(name string, required bool) Option {
 	return func(c *Command) {
-		c.arguments = append(c.arguments, &Argument{name, required})
+		c.Args = append(c.Args, &Argument{name, required})
 	}
 }
 
 func WithArguments(args ...*Argument) Option {
 	return func(c *Command) {
-		c.arguments = append(c.arguments, args...)
+		c.Args = append(c.Args, args...)
 	}
 }
 
-func WithOption(f opts.Option) Option {
+func WithOption(f opt.Option) Option {
 	return func(c *Command) {
-		c.opts = append(c.opts, f)
+		c.Opts = append(c.Opts, f)
 	}
 }
 
-func WithOptions(os ...opts.Option) Option {
+func WithOptions(os ...opt.Option) Option {
 	return func(c *Command) {
-		c.opts = append(c.opts, os...)
+		c.Opts = append(c.Opts, os...)
 	}
 }
 
 func WithSubcommand(s *Command) Option {
 	return func(c *Command) {
-		c.subcommands.Add(c)
-		s.parent = c
+		c.Subcommands.Add(s)
+		s.Parent = c
 	}
 }
 
 func WithSubcommands(ss ...*Command) Option {
 	return func(c *Command) {
-		c.subcommands.Add(c)
 		for _, s := range ss {
-			s.parent = c
+			c.Subcommands.Add(s)
+			s.Parent = c
 		}
 	}
 }
 
 func WithParent(p *Command) Option {
 	return func(c *Command) {
-		c.parent = p
-		p.subcommands.Add(c)
+		c.Parent = p
+		p.Subcommands.Add(c)
 	}
 }
 

set.go

@@ -12,11 +12,11 @@ func (s *Set) Add(c *Command) {
 
 func (s Set) Get(name string) (*Command, bool) {
 	for _, c := range s {
-		if c.name == name {
+		if c.Name == name {
 			return c, true
 		}
 
-		for _, alias := range c.aliases {
+		for _, alias := range c.Aliases {
 			if alias == name {
 				return c, true
 			}
@@ -25,16 +25,25 @@ func (s Set) Get(name string) (*Command, bool) {
 	return nil, false
 }
 
-func (s Set) MaxNameWidth() int {
+func (s Set) MaxWidth() int {
 	max := 0
 	for _, f := range s {
-		if w := len(f.name); w > max {
+		if w := len(f.Name); w > max {
 			max = w
 		}
 	}
 	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

@@ -0,0 +1,99 @@
+package cmd
+
+import (
+	"fmt"
+	"strings"
+	"text/template"
+
+	"github.com/iancoleman/strcase"
+)
+
+var tplFuncs = template.FuncMap{
+	"map":       tplMap,
+	"cat":       tplCat,
+	"split":     tplSplit,
+	"join":      tplJoin,
+	"under":     tplUnder,
+	"varPrefix": tplVarPrefix,
+	"repeat":    tplRepeat,
+	"indent":    tplIndent,
+	"add":       tplAdd,
+	"inc":       tplInc,
+	"sub":       tplSub,
+	"dec":       tplDec,
+	"mult":      tplMult,
+	"pascal":    tplPascal,
+	"camel":     tplCamel,
+}
+
+func tplMap(vals ...any) (map[string]any, error) {
+	if len(vals)%2 != 0 {
+		return nil, fmt.Errorf("missing value, need one key and one value per kv pair")
+	}
+
+	m := make(map[string]any)
+	for i := 0; i < len(vals); i += 2 {
+		m[vals[i].(string)] = vals[i+1]
+	}
+	return m, nil
+}
+
+func tplCat(strs ...string) string {
+	return strings.Join(strs, "")
+}
+
+func tplSplit(s string, sep string) []string {
+	return strings.Split(s, sep)
+}
+
+func tplJoin(strs []string, sep string) string {
+	return strings.Join(strs, sep)
+}
+
+func tplUnder(s string) string {
+	return strcase.ToSnake(s)
+}
+
+func tplVarPrefix(s string) string {
+	if s == "" {
+		return ""
+	}
+
+	return tplUnder(s) + "_"
+}
+
+func tplRepeat(s string, n int) string {
+	return strings.Repeat(s, n)
+}
+
+func tplIndent(n int) string {
+	return tplRepeat(" ", n)
+}
+
+func tplAdd(a, b int) int {
+	return a + b
+}
+
+func tplInc(i int) int {
+	return tplAdd(i, 1)
+}
+
+func tplSub(a, b int) int {
+	return a - b
+}
+
+func tplDec(i int) int {
+	return tplSub(i, 1)
+}
+
+func tplMult(a, b int) int {
+	return a * b
+}
+
+func tplPascal(s string) string {
+	return strcase.ToCamel(s)
+}
+
+func tplCamel(s string) string {
+	return strcase.ToLowerCamel(s)
+}