chord/vendor/github.com/urfave/cli/v3/help.go
2025-03-15 20:42:37 -04:00

597 lines
16 KiB
Go

package cli
import (
"context"
"fmt"
"io"
"os"
"strings"
"text/tabwriter"
"text/template"
"unicode/utf8"
)
const (
helpName = "help"
helpAlias = "h"
)
// Prints help for the App or Command
type helpPrinter func(w io.Writer, templ string, data interface{})
// Prints help for the App or Command with custom template function.
type helpPrinterCustom func(w io.Writer, templ string, data interface{}, customFunc map[string]interface{})
// HelpPrinter is a function that writes the help output. If not set explicitly,
// this calls HelpPrinterCustom using only the default template functions.
//
// If custom logic for printing help is required, this function can be
// overridden. If the ExtraInfo field is defined on an App, this function
// should not be modified, as HelpPrinterCustom will be used directly in order
// to capture the extra information.
var HelpPrinter helpPrinter = printHelp
// HelpPrinterCustom is a function that writes the help output. It is used as
// the default implementation of HelpPrinter, and may be called directly if
// the ExtraInfo field is set on an App.
//
// In the default implementation, if the customFuncs argument contains a
// "wrapAt" key, which is a function which takes no arguments and returns
// an int, this int value will be used to produce a "wrap" function used
// by the default template to wrap long lines.
var HelpPrinterCustom helpPrinterCustom = printHelpCustom
// VersionPrinter prints the version for the App
var VersionPrinter = printVersion
func buildHelpCommand(withAction bool) *Command {
cmd := &Command{
Name: helpName,
Aliases: []string{helpAlias},
Usage: "Shows a list of commands or help for one command",
ArgsUsage: "[command]",
HideHelp: true,
}
if withAction {
cmd.Action = helpCommandAction
}
return cmd
}
func helpCommandAction(ctx context.Context, cmd *Command) error {
args := cmd.Args()
firstArg := args.First()
tracef("doing help for cmd %[1]q with args %[2]q", cmd, args)
// This action can be triggered by a "default" action of a command
// or via cmd.Run when cmd == helpCmd. So we have following possibilities
//
// 1 $ app
// 2 $ app help
// 3 $ app foo
// 4 $ app help foo
// 5 $ app foo help
// Case 4. when executing a help command set the context to parent
// to allow resolution of subsequent args. This will transform
// $ app help foo
// to
// $ app foo
// which will then be handled as case 3
if cmd.parent != nil && (cmd.HasName(helpName) || cmd.HasName(helpAlias)) {
tracef("setting cmd to cmd.parent")
cmd = cmd.parent
}
// Case 4. $ app help foo
// foo is the command for which help needs to be shown
if firstArg != "" {
if firstArg == "--" {
return nil
}
tracef("returning ShowCommandHelp with %[1]q", firstArg)
return ShowCommandHelp(ctx, cmd, firstArg)
}
// Case 1 & 2
// Special case when running help on main app itself as opposed to individual
// commands/subcommands
if cmd.parent == nil {
tracef("returning ShowAppHelp")
_ = ShowAppHelp(cmd)
return nil
}
// Case 3, 5
if (len(cmd.Commands) == 1 && !cmd.HideHelp) ||
(len(cmd.Commands) == 0 && cmd.HideHelp) {
tmpl := cmd.CustomHelpTemplate
if tmpl == "" {
tmpl = CommandHelpTemplate
}
tracef("running HelpPrinter with command %[1]q", cmd.Name)
HelpPrinter(cmd.Root().Writer, tmpl, cmd)
return nil
}
tracef("running ShowSubcommandHelp")
return ShowSubcommandHelp(cmd)
}
// ShowAppHelpAndExit - Prints the list of subcommands for the app and exits with exit code.
func ShowAppHelpAndExit(cmd *Command, exitCode int) {
_ = ShowAppHelp(cmd)
os.Exit(exitCode)
}
// ShowAppHelp is an action that displays the help.
func ShowAppHelp(cmd *Command) error {
tmpl := cmd.CustomRootCommandHelpTemplate
if tmpl == "" {
tracef("using RootCommandHelpTemplate")
tmpl = RootCommandHelpTemplate
}
if cmd.ExtraInfo == nil {
HelpPrinter(cmd.Root().Writer, tmpl, cmd.Root())
return nil
}
tracef("setting ExtraInfo in customAppData")
customAppData := func() map[string]any {
return map[string]any{
"ExtraInfo": cmd.ExtraInfo,
}
}
HelpPrinterCustom(cmd.Root().Writer, tmpl, cmd.Root(), customAppData())
return nil
}
// DefaultAppComplete prints the list of subcommands as the default app completion method
func DefaultAppComplete(ctx context.Context, cmd *Command) {
DefaultCompleteWithFlags(ctx, cmd)
}
func printCommandSuggestions(commands []*Command, writer io.Writer) {
for _, command := range commands {
if command.Hidden {
continue
}
if strings.HasSuffix(os.Getenv("SHELL"), "zsh") {
_, _ = fmt.Fprintf(writer, "%s:%s\n", command.Name, command.Usage)
} else {
_, _ = fmt.Fprintf(writer, "%s\n", command.Name)
}
}
}
func cliArgContains(flagName string, args []string) bool {
for _, name := range strings.Split(flagName, ",") {
name = strings.TrimSpace(name)
count := utf8.RuneCountInString(name)
if count > 2 {
count = 2
}
flag := fmt.Sprintf("%s%s", strings.Repeat("-", count), name)
for _, a := range args {
if a == flag {
return true
}
}
}
return false
}
func printFlagSuggestions(lastArg string, flags []Flag, writer io.Writer) {
// Trim to handle both "-short" and "--long" flags.
cur := strings.TrimLeft(lastArg, "-")
for _, flag := range flags {
if bflag, ok := flag.(*BoolFlag); ok && bflag.Hidden {
continue
}
usage := ""
if docFlag, ok := flag.(DocGenerationFlag); ok {
usage = docFlag.GetUsage()
}
name := strings.TrimSpace(flag.Names()[0])
// this will get total count utf8 letters in flag name
count := utf8.RuneCountInString(name)
if count > 2 {
count = 2 // reuse this count to generate single - or -- in flag completion
}
// if flag name has more than one utf8 letter and last argument in cli has -- prefix then
// skip flag completion for short flags example -v or -x
if strings.HasPrefix(lastArg, "--") && count == 1 {
continue
}
// match if last argument matches this flag and it is not repeated
if strings.HasPrefix(name, cur) && cur != name && !cliArgContains(name, os.Args) {
flagCompletion := fmt.Sprintf("%s%s", strings.Repeat("-", count), name)
if usage != "" && strings.HasSuffix(os.Getenv("SHELL"), "zsh") {
flagCompletion = fmt.Sprintf("%s:%s", flagCompletion, usage)
}
fmt.Fprintln(writer, flagCompletion)
}
}
}
func DefaultCompleteWithFlags(ctx context.Context, cmd *Command) {
args := os.Args
if cmd != nil && cmd.flagSet != nil && cmd.parent != nil {
args = cmd.Args().Slice()
tracef("running default complete with flags[%v] on command %[2]q", args, cmd.Name)
} else {
tracef("running default complete with os.Args flags[%v]", args)
}
argsLen := len(args)
lastArg := ""
// parent command will have --generate-shell-completion so we need
// to account for that
if argsLen > 1 {
lastArg = args[argsLen-2]
} else if argsLen > 0 {
lastArg = args[argsLen-1]
}
if lastArg == "--" {
tracef("not printing flag suggestion as last arg is --")
return
}
if strings.HasPrefix(lastArg, "-") {
tracef("printing flag suggestion for flag[%v] on command %[1]q", lastArg, cmd.Name)
printFlagSuggestions(lastArg, cmd.Flags, cmd.Root().Writer)
return
}
if cmd != nil {
tracef("printing command suggestions on command %[1]q", cmd.Name)
printCommandSuggestions(cmd.Commands, cmd.Root().Writer)
return
}
}
// ShowCommandHelpAndExit - exits with code after showing help
func ShowCommandHelpAndExit(ctx context.Context, cmd *Command, command string, code int) {
_ = ShowCommandHelp(ctx, cmd, command)
os.Exit(code)
}
// ShowCommandHelp prints help for the given command
func ShowCommandHelp(ctx context.Context, cmd *Command, commandName string) error {
for _, subCmd := range cmd.Commands {
if !subCmd.HasName(commandName) {
continue
}
tmpl := subCmd.CustomHelpTemplate
if tmpl == "" {
if len(subCmd.Commands) == 0 {
tracef("using CommandHelpTemplate")
tmpl = CommandHelpTemplate
} else {
tracef("using SubcommandHelpTemplate")
tmpl = SubcommandHelpTemplate
}
}
tracef("running HelpPrinter")
HelpPrinter(cmd.Root().Writer, tmpl, subCmd)
tracef("returning nil after printing help")
return nil
}
tracef("no matching command found")
if cmd.CommandNotFound == nil {
errMsg := fmt.Sprintf("No help topic for '%v'", commandName)
if cmd.Suggest {
if suggestion := SuggestCommand(cmd.Commands, commandName); suggestion != "" {
errMsg += ". " + suggestion
}
}
tracef("exiting 3 with errMsg %[1]q", errMsg)
return Exit(errMsg, 3)
}
tracef("running CommandNotFound func for %[1]q", commandName)
cmd.CommandNotFound(ctx, cmd, commandName)
return nil
}
// ShowSubcommandHelpAndExit - Prints help for the given subcommand and exits with exit code.
func ShowSubcommandHelpAndExit(cmd *Command, exitCode int) {
_ = ShowSubcommandHelp(cmd)
os.Exit(exitCode)
}
// ShowSubcommandHelp prints help for the given subcommand
func ShowSubcommandHelp(cmd *Command) error {
HelpPrinter(cmd.Root().Writer, SubcommandHelpTemplate, cmd)
return nil
}
// ShowVersion prints the version number of the App
func ShowVersion(cmd *Command) {
tracef("showing version via VersionPrinter (cmd=%[1]q)", cmd.Name)
VersionPrinter(cmd)
}
func printVersion(cmd *Command) {
_, _ = fmt.Fprintf(cmd.Root().Writer, "%v version %v\n", cmd.Name, cmd.Version)
}
func handleTemplateError(err error) {
if err != nil {
tracef("error encountered during template parse: %[1]v", err)
// If the writer is closed, t.Execute will fail, and there's nothing
// we can do to recover.
if os.Getenv("CLI_TEMPLATE_ERROR_DEBUG") != "" {
_, _ = fmt.Fprintf(ErrWriter, "CLI TEMPLATE ERROR: %#v\n", err)
}
return
}
}
// printHelpCustom is the default implementation of HelpPrinterCustom.
//
// The customFuncs map will be combined with a default template.FuncMap to
// allow using arbitrary functions in template rendering.
func printHelpCustom(out io.Writer, templ string, data interface{}, customFuncs map[string]interface{}) {
const maxLineLength = 10000
tracef("building default funcMap")
funcMap := template.FuncMap{
"join": strings.Join,
"subtract": subtract,
"indent": indent,
"nindent": nindent,
"trim": strings.TrimSpace,
"wrap": func(input string, offset int) string { return wrap(input, offset, maxLineLength) },
"offset": offset,
"offsetCommands": offsetCommands,
}
if wa, ok := customFuncs["wrapAt"]; ok {
if wrapAtFunc, ok := wa.(func() int); ok {
wrapAt := wrapAtFunc()
customFuncs["wrap"] = func(input string, offset int) string {
return wrap(input, offset, wrapAt)
}
}
}
for key, value := range customFuncs {
funcMap[key] = value
}
w := tabwriter.NewWriter(out, 1, 8, 2, ' ', 0)
t := template.Must(template.New("help").Funcs(funcMap).Parse(templ))
if _, err := t.New("helpNameTemplate").Parse(helpNameTemplate); err != nil {
handleTemplateError(err)
}
if _, err := t.New("argsTemplate").Parse(argsTemplate); err != nil {
handleTemplateError(err)
}
if _, err := t.New("usageTemplate").Parse(usageTemplate); err != nil {
handleTemplateError(err)
}
if _, err := t.New("descriptionTemplate").Parse(descriptionTemplate); err != nil {
handleTemplateError(err)
}
if _, err := t.New("visibleCommandTemplate").Parse(visibleCommandTemplate); err != nil {
handleTemplateError(err)
}
if _, err := t.New("copyrightTemplate").Parse(copyrightTemplate); err != nil {
handleTemplateError(err)
}
if _, err := t.New("versionTemplate").Parse(versionTemplate); err != nil {
handleTemplateError(err)
}
if _, err := t.New("visibleFlagCategoryTemplate").Parse(visibleFlagCategoryTemplate); err != nil {
handleTemplateError(err)
}
if _, err := t.New("visibleFlagTemplate").Parse(visibleFlagTemplate); err != nil {
handleTemplateError(err)
}
if _, err := t.New("visiblePersistentFlagTemplate").Parse(visiblePersistentFlagTemplate); err != nil {
handleTemplateError(err)
}
if _, err := t.New("visibleGlobalFlagCategoryTemplate").Parse(strings.Replace(visibleFlagCategoryTemplate, "OPTIONS", "GLOBAL OPTIONS", -1)); err != nil {
handleTemplateError(err)
}
if _, err := t.New("authorsTemplate").Parse(authorsTemplate); err != nil {
handleTemplateError(err)
}
if _, err := t.New("visibleCommandCategoryTemplate").Parse(visibleCommandCategoryTemplate); err != nil {
handleTemplateError(err)
}
tracef("executing template")
handleTemplateError(t.Execute(w, data))
_ = w.Flush()
}
func printHelp(out io.Writer, templ string, data interface{}) {
HelpPrinterCustom(out, templ, data, nil)
}
func checkVersion(cmd *Command) bool {
found := false
for _, name := range VersionFlag.Names() {
if cmd.Bool(name) {
found = true
}
}
return found
}
func checkShellCompleteFlag(c *Command, arguments []string) (bool, []string) {
if (c.parent == nil && !c.EnableShellCompletion) || (c.parent != nil && !c.Root().shellCompletion) {
return false, arguments
}
pos := len(arguments) - 1
lastArg := arguments[pos]
if lastArg != completionFlag {
return false, arguments
}
for _, arg := range arguments {
// If arguments include "--", shell completion is disabled
// because after "--" only positional arguments are accepted.
// https://unix.stackexchange.com/a/11382
if arg == "--" {
return false, arguments[:pos]
}
}
return true, arguments[:pos]
}
func checkCompletions(ctx context.Context, cmd *Command) bool {
tracef("checking completions on command %[1]q", cmd.Name)
if !cmd.Root().shellCompletion {
tracef("completion not enabled skipping %[1]q", cmd.Name)
return false
}
if argsArguments := cmd.Args(); argsArguments.Present() {
name := argsArguments.First()
if cmd := cmd.Command(name); cmd != nil {
// let the command handle the completion
return false
}
}
tracef("no subcommand found for completiot %[1]q", cmd.Name)
if cmd.ShellComplete != nil {
tracef("running shell completion func for command %[1]q", cmd.Name)
cmd.ShellComplete(ctx, cmd)
}
return true
}
func subtract(a, b int) int {
return a - b
}
func indent(spaces int, v string) string {
pad := strings.Repeat(" ", spaces)
return pad + strings.Replace(v, "\n", "\n"+pad, -1)
}
func nindent(spaces int, v string) string {
return "\n" + indent(spaces, v)
}
func wrap(input string, offset int, wrapAt int) string {
var ss []string
lines := strings.Split(input, "\n")
padding := strings.Repeat(" ", offset)
for i, line := range lines {
if line == "" {
ss = append(ss, line)
} else {
wrapped := wrapLine(line, offset, wrapAt, padding)
if i == 0 {
ss = append(ss, wrapped)
} else {
ss = append(ss, padding+wrapped)
}
}
}
return strings.Join(ss, "\n")
}
func wrapLine(input string, offset int, wrapAt int, padding string) string {
if wrapAt <= offset || len(input) <= wrapAt-offset {
return input
}
lineWidth := wrapAt - offset
words := strings.Fields(input)
if len(words) == 0 {
return input
}
wrapped := words[0]
spaceLeft := lineWidth - len(wrapped)
for _, word := range words[1:] {
if len(word)+1 > spaceLeft {
wrapped += "\n" + padding + word
spaceLeft = lineWidth - len(word)
} else {
wrapped += " " + word
spaceLeft -= 1 + len(word)
}
}
return wrapped
}
func offset(input string, fixed int) int {
return len(input) + fixed
}
// this function tries to find the max width of the names column
// so say we have the following rows for help
//
// foo1, foo2, foo3 some string here
// bar1, b2 some other string here
//
// We want to offset the 2nd row usage by some amount so that everything
// is aligned
//
// foo1, foo2, foo3 some string here
// bar1, b2 some other string here
//
// to find that offset we find the length of all the rows and use the max
// to calculate the offset
func offsetCommands(cmds []*Command, fixed int) int {
max := 0
for _, cmd := range cmds {
s := strings.Join(cmd.Names(), ", ")
if len(s) > max {
max = len(s)
}
}
return max + fixed
}