Merge branch 'master' into suggestions

app.go

@@ -43,8 +43,11 @@ type App struct {
 	Flags []Flag
 	// Boolean to enable bash completion commands
 	EnableBashCompletion bool
-	// Boolean to hide built-in help command
+	// Boolean to hide built-in help command and help flag
 	HideHelp bool
+	// Boolean to hide built-in help command but keep help flag.
+	// Ignored if HideHelp is true.
+	HideHelpCommand bool
 	// Boolean to hide built-in version flag and the VERSION section of help
 	HideVersion bool
 	// categories contains the categorized commands and is populated on app startup
@@ -61,7 +64,7 @@ type App struct {
 	Action ActionFunc
 	// Execute this function if the proper command cannot be found
 	CommandNotFound CommandNotFoundFunc
-	// Execute this function if an usage error occurs
+	// Execute this function if a usage error occurs
 	OnUsageError OnUsageErrorFunc
 	// Compilation date
 	Compiled time.Time
@@ -69,12 +72,15 @@ type App struct {
 	Authors []*Author
 	// Copyright of the binary if any
 	Copyright string
+	// Reader reader to write input to (useful for tests)
+	Reader io.Reader
 	// Writer writer to write output to
 	Writer io.Writer
 	// ErrWriter writes error output
 	ErrWriter io.Writer
-	// Execute this function to handle ExitErrors. If not provided, HandleExitCoder is provided to
-	// function as a default, so this is optional.
+	// ExitErrHandler processes any error encountered while running an App before
+	// it is returned to the caller. If no function is provided, HandleExitCoder
+	// is used as the default behavior.
 	ExitErrHandler ExitErrHandlerFunc
 	// Other custom info
 	Metadata map[string]interface{}
@@ -115,7 +121,9 @@ func NewApp() *App {
 		BashComplete: DefaultAppComplete,
 		Action:       helpCommand.Action,
 		Compiled:     compileTime(),
+		Reader:       os.Stdin,
 		Writer:       os.Stdout,
+		ErrWriter:    os.Stderr,
 	}
 }
 
@@ -134,7 +142,7 @@ func (a *App) Setup() {
 	}
 
 	if a.HelpName == "" {
-		a.HelpName = filepath.Base(os.Args[0])
+		a.HelpName = a.Name
 	}
 
 	if a.Usage == "" {
@@ -157,10 +165,18 @@ func (a *App) Setup() {
 		a.Compiled = compileTime()
 	}
 
+	if a.Reader == nil {
+		a.Reader = os.Stdin
+	}
+
 	if a.Writer == nil {
 		a.Writer = os.Stdout
 	}
 
+	if a.ErrWriter == nil {
+		a.ErrWriter = os.Stderr
+	}
+
 	var newCommands []*Command
 
 	for _, c := range a.Commands {
@@ -172,7 +188,9 @@ func (a *App) Setup() {
 	a.Commands = newCommands
 
 	if a.Command(helpCommand.Name) == nil && !a.HideHelp {
-		a.appendCommand(helpCommand)
+		if !a.HideHelpCommand {
+			a.appendCommand(helpCommand)
+		}
 
 		if HelpFlag != nil {
 			a.appendFlag(HelpFlag)
@@ -192,10 +210,6 @@ func (a *App) Setup() {
 	if a.Metadata == nil {
 		a.Metadata = make(map[string]interface{})
 	}
-
-	if a.Writer == nil {
-		a.Writer = os.Stdout
-	}
 }
 
 func (a *App) newFlagSet() (*flag.FlagSet, error) {
@@ -271,7 +285,7 @@ func (a *App) RunContext(ctx context.Context, arguments []string) (err error) {
 		return nil
 	}
 
-	cerr := checkRequiredFlags(a.Flags, context)
+	cerr := context.checkRequiredFlags(a.Flags)
 	if cerr != nil {
 		_ = ShowAppHelp(context)
 		return cerr
@@ -292,8 +306,6 @@ func (a *App) RunContext(ctx context.Context, arguments []string) (err error) {
 	if a.Before != nil {
 		beforeErr := a.Before(context)
 		if beforeErr != nil {
-			_, _ = fmt.Fprintf(a.Writer, "%v\n\n", beforeErr)
-			_ = ShowAppHelp(context)
 			a.handleExitCoder(context, beforeErr)
 			err = beforeErr
 			return err
@@ -323,11 +335,11 @@ func (a *App) RunContext(ctx context.Context, arguments []string) (err error) {
 // RunAndExitOnError calls .Run() and exits non-zero if an error was returned
 //
 // Deprecated: instead you should return an error that fulfills cli.ExitCoder
-// to cli.App.Run. This will cause the application to exit with the given eror
+// to cli.App.Run. This will cause the application to exit with the given error
 // code in the cli.ExitCoder
 func (a *App) RunAndExitOnError() {
 	if err := a.Run(os.Args); err != nil {
-		_, _ = fmt.Fprintln(a.errWriter(), err)
+		_, _ = fmt.Fprintln(a.ErrWriter, err)
 		OsExiter(1)
 	}
 }
@@ -335,19 +347,9 @@ func (a *App) RunAndExitOnError() {
 // RunAsSubcommand invokes the subcommand given the context, parses ctx.Args() to
 // generate command-specific flags
 func (a *App) RunAsSubcommand(ctx *Context) (err error) {
+	// Setup also handles HideHelp and HideHelpCommand
 	a.Setup()
 
-	// append help to commands
-	if len(a.Commands) > 0 {
-		if a.Command(helpCommand.Name) == nil && !a.HideHelp {
-			a.appendCommand(helpCommand)
-
-			if HelpFlag != nil {
-				a.appendFlag(HelpFlag)
-			}
-		}
-	}
-
 	var newCmds []*Command
 	for _, c := range a.Commands {
 		if c.HelpName == "" {
@@ -407,7 +409,7 @@ func (a *App) RunAsSubcommand(ctx *Context) (err error) {
 		}
 	}
 
-	cerr := checkRequiredFlags(a.Flags, context)
+	cerr := context.checkRequiredFlags(a.Flags)
 	if cerr != nil {
 		_ = ShowSubcommandHelp(context)
 		return cerr
@@ -496,15 +498,6 @@ func (a *App) VisibleFlags() []Flag {
 	return visibleFlags(a.Flags)
 }
 
-func (a *App) errWriter() io.Writer {
-	// When the app ErrWriter is nil use the package level one.
-	if a.ErrWriter == nil {
-		return ErrWriter
-	}
-
-	return a.ErrWriter
-}
-
 func (a *App) appendFlag(fl Flag) {
 	if !hasFlag(a.Flags, fl) {
 		a.Flags = append(a.Flags, fl)