merging code

app.go

@@ -64,6 +64,7 @@ func (a *App) Run(arguments []string) error {
 	}
 
 	//append version/help flags
+	a.appendFlag(BoolFlag{"generate-bash-completion", ""})
 	a.appendFlag(BoolFlag{"version, v", "print the version"})
 	a.appendFlag(BoolFlag{"help, h", "show help"})
 
@@ -88,6 +89,10 @@ func (a *App) Run(arguments []string) error {
 		return err
 	}
 
+	if checkCompletions(context) {
+		return nil
+	}
+
 	if checkHelp(context) {
 		return nil
 	}

command.go

@@ -16,6 +16,8 @@ type Command struct {
 	Usage string
 	// A longer explaination of how the command works
 	Description string
+	// The function to call when checking for bash command completions
+	BashComplete func(context *Context)
 	// The function to call when this command is invoked
 	Action func(context *Context)
 	// List of flags to parse
@@ -27,6 +29,7 @@ func (c Command) Run(ctx *Context) error {
 	// append help to flags
 	c.Flags = append(
 		c.Flags,
+		BoolFlag{"generate-bash-completion", ""},
 		BoolFlag{"help, h", "show help"},
 	)
 
@@ -67,6 +70,11 @@ func (c Command) Run(ctx *Context) error {
 		return nerr
 	}
 	context := NewContext(ctx.App, set, ctx.globalSet)
+
+	if checkCommandCompletions(context, c.Name) {
+		return nil
+	}
+
 	if checkCommandHelp(context, c.Name) {
 		return nil
 	}

help.go

@@ -81,6 +81,24 @@ func ShowVersion(c *Context) {
 	fmt.Printf("%v version %v\n", c.App.Name, c.App.Version)
 }
 
+// Prints the lists of commands within a given context
+func ShowCompletions(c *Context) {
+	for _, command := range c.App.Commands {
+		fmt.Println(command.Name)
+		if command.ShortName != "" {
+			fmt.Println(command.ShortName)
+		}
+	}
+}
+
+// Prints the custom completions for a given command
+func ShowCommandCompletions(ctx *Context, command string) {
+	c := ctx.App.Command(command)
+	if c != nil && c.BashComplete != nil {
+		c.BashComplete(ctx)
+	}
+}
+
 func printHelp(templ string, data interface{}) {
 	w := tabwriter.NewWriter(os.Stdout, 0, 8, 1, '\t', 0)
 	t := template.Must(template.New("help").Parse(templ))
@@ -117,3 +135,21 @@ func checkCommandHelp(c *Context, name string) bool {
 
 	return false
 }
+
+func checkCompletions(c *Context) bool {
+	if c.GlobalBool("generate-bash-completion") {
+		ShowCompletions(c)
+		return true
+	}
+
+	return false
+}
+
+func checkCommandCompletions(c *Context, name string) bool {
+	if c.Bool("generate-bash-completion") {
+		ShowCommandCompletions(c, name)
+		return true
+	}
+
+	return false
+}