Add command to generate man pages

The climan package has a command that can be registered with any urfav
cli app to generate man pages.

Signed-off-by: Michael Crosby <crosbymichael@gmail.com>

vendor/github.com/urfave/cli/app.go

@@ -1,9 +1,9 @@
 package cli
 
 import (
+	"flag"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"os"
 	"path/filepath"
 	"sort"
@@ -11,9 +11,10 @@ import (
 )
 
 var (
-	changeLogURL                    = "https://github.com/urfave/cli/blob/master/CHANGELOG.md"
-	appActionDeprecationURL         = fmt.Sprintf("%s#deprecated-cli-app-action-signature", changeLogURL)
-	runAndExitOnErrorDeprecationURL = fmt.Sprintf("%s#deprecated-cli-app-runandexitonerror", changeLogURL)
+	changeLogURL            = "https://github.com/urfave/cli/blob/master/CHANGELOG.md"
+	appActionDeprecationURL = fmt.Sprintf("%s#deprecated-cli-app-action-signature", changeLogURL)
+	// unused variable. commented for now. will remove in future if agreed upon by everyone
+	//runAndExitOnErrorDeprecationURL = fmt.Sprintf("%s#deprecated-cli-app-runandexitonerror", changeLogURL)
 
 	contactSysadmin = "This is an error in the application.  Please contact the distributor of this application if this is not you."
 
@@ -94,6 +95,10 @@ type App struct {
 	// cli.go uses text/template to render templates. You can
 	// render custom help text by setting this variable.
 	CustomAppHelpTemplate string
+	// Boolean to enable short-option handling so user can combine several
+	// single-character bool arguements into one
+	// i.e. foobar -o -v -> foobar -ov
+	UseShortOptionHandling bool
 
 	didSetup bool
 }
@@ -138,7 +143,7 @@ func (a *App) Setup() {
 		a.Authors = append(a.Authors, Author{Name: a.Author, Email: a.Email})
 	}
 
-	newCmds := []Command{}
+	var newCmds []Command
 	for _, c := range a.Commands {
 		if c.HelpName == "" {
 			c.HelpName = fmt.Sprintf("%s %s", a.HelpName, c.Name)
@@ -173,6 +178,14 @@ func (a *App) Setup() {
 	}
 }
 
+func (a *App) newFlagSet() (*flag.FlagSet, error) {
+	return flagSet(a.Name, a.Flags)
+}
+
+func (a *App) useShortOptionHandling() bool {
+	return a.UseShortOptionHandling
+}
+
 // Run is the entry point to the cli app. Parses the arguments slice and routes
 // to the proper flag/args combination
 func (a *App) Run(arguments []string) (err error) {
@@ -186,19 +199,17 @@ func (a *App) Run(arguments []string) (err error) {
 	// always appends the completion flag at the end of the command
 	shellComplete, arguments := checkShellCompleteFlag(a, arguments)
 
-	// parse flags
-	set, err := flagSet(a.Name, a.Flags)
+	_, err = a.newFlagSet()
 	if err != nil {
 		return err
 	}
 
-	set.SetOutput(ioutil.Discard)
-	err = set.Parse(arguments[1:])
+	set, err := parseIter(a, arguments[1:])
 	nerr := normalizeFlags(a.Flags, set)
 	context := NewContext(a, set, nil)
 	if nerr != nil {
-		fmt.Fprintln(a.Writer, nerr)
-		ShowAppHelp(context)
+		_, _ = fmt.Fprintln(a.Writer, nerr)
+		_ = ShowAppHelp(context)
 		return nerr
 	}
 	context.shellComplete = shellComplete
@@ -213,13 +224,13 @@ func (a *App) Run(arguments []string) (err error) {
 			a.handleExitCoder(context, err)
 			return err
 		}
-		fmt.Fprintf(a.Writer, "%s %s\n\n", "Incorrect Usage.", err.Error())
-		ShowAppHelp(context)
+		_, _ = fmt.Fprintf(a.Writer, "%s %s\n\n", "Incorrect Usage.", err.Error())
+		_ = ShowAppHelp(context)
 		return err
 	}
 
 	if !a.HideHelp && checkHelp(context) {
-		ShowAppHelp(context)
+		_ = ShowAppHelp(context)
 		return nil
 	}
 
@@ -228,6 +239,12 @@ func (a *App) Run(arguments []string) (err error) {
 		return nil
 	}
 
+	cerr := checkRequiredFlags(a.Flags, context)
+	if cerr != nil {
+		_ = ShowAppHelp(context)
+		return cerr
+	}
+
 	if a.After != nil {
 		defer func() {
 			if afterErr := a.After(context); afterErr != nil {
@@ -243,8 +260,8 @@ func (a *App) Run(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)
+			_, _ = fmt.Fprintf(a.Writer, "%v\n\n", beforeErr)
+			_ = ShowAppHelp(context)
 			a.handleExitCoder(context, beforeErr)
 			err = beforeErr
 			return err
@@ -278,7 +295,7 @@ func (a *App) Run(arguments []string) (err 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)
 	}
 }
@@ -305,24 +322,22 @@ func (a *App) RunAsSubcommand(ctx *Context) (err error) {
 	}
 	a.Commands = newCmds
 
-	// parse flags
-	set, err := flagSet(a.Name, a.Flags)
+	_, err = a.newFlagSet()
 	if err != nil {
 		return err
 	}
 
-	set.SetOutput(ioutil.Discard)
-	err = set.Parse(ctx.Args().Tail())
+	set, err := parseIter(a, ctx.Args().Tail())
 	nerr := normalizeFlags(a.Flags, set)
 	context := NewContext(a, set, ctx)
 
 	if nerr != nil {
-		fmt.Fprintln(a.Writer, nerr)
-		fmt.Fprintln(a.Writer)
+		_, _ = fmt.Fprintln(a.Writer, nerr)
+		_, _ = fmt.Fprintln(a.Writer)
 		if len(a.Commands) > 0 {
-			ShowSubcommandHelp(context)
+			_ = ShowSubcommandHelp(context)
 		} else {
-			ShowCommandHelp(ctx, context.Args().First())
+			_ = ShowCommandHelp(ctx, context.Args().First())
 		}
 		return nerr
 	}
@@ -337,8 +352,8 @@ func (a *App) RunAsSubcommand(ctx *Context) (err error) {
 			a.handleExitCoder(context, err)
 			return err
 		}
-		fmt.Fprintf(a.Writer, "%s %s\n\n", "Incorrect Usage.", err.Error())
-		ShowSubcommandHelp(context)
+		_, _ = fmt.Fprintf(a.Writer, "%s %s\n\n", "Incorrect Usage.", err.Error())
+		_ = ShowSubcommandHelp(context)
 		return err
 	}
 
@@ -352,6 +367,12 @@ func (a *App) RunAsSubcommand(ctx *Context) (err error) {
 		}
 	}
 
+	cerr := checkRequiredFlags(a.Flags, context)
+	if cerr != nil {
+		_ = ShowSubcommandHelp(context)
+		return cerr
+	}
+
 	if a.After != nil {
 		defer func() {
 			afterErr := a.After(context)
@@ -428,7 +449,7 @@ func (a *App) VisibleCategories() []*CommandCategory {
 
 // VisibleCommands returns a slice of the Commands with Hidden=false
 func (a *App) VisibleCommands() []Command {
-	ret := []Command{}
+	var ret []Command
 	for _, command := range a.Commands {
 		if !command.Hidden {
 			ret = append(ret, command)
@@ -453,7 +474,6 @@ func (a *App) hasFlag(flag Flag) bool {
 }
 
 func (a *App) errWriter() io.Writer {
-
 	// When the app ErrWriter is nil use the package level one.
 	if a.ErrWriter == nil {
 		return ErrWriter
@@ -496,11 +516,12 @@ func (a Author) String() string {
 // it's an ActionFunc or a func with the legacy signature for Action, the func
 // is run!
 func HandleAction(action interface{}, context *Context) (err error) {
-	if a, ok := action.(ActionFunc); ok {
+	switch a := action.(type) {
+	case ActionFunc:
 		return a(context)
-	} else if a, ok := action.(func(*Context) error); ok {
+	case func(*Context) error:
 		return a(context)
-	} else if a, ok := action.(func(*Context)); ok { // deprecated function signature
+	case func(*Context): // deprecated function signature
 		a(context)
 		return nil
 	}