Sets a subcommand's parent cmd

This allows the help output to show the correct/full command path to the
subcommand.

Signed-off-by: Brian Goff <cpuguy83@gmail.com>

app_test.go

@@ -735,6 +735,36 @@ func TestApp_Run_CommandWithSubcommandHasHelpTopic(t *testing.T) {
 	}
 }
 
+func TestApp_Run_SubcommandFullPath(t *testing.T) {
+	app := cli.NewApp()
+	buf := new(bytes.Buffer)
+	app.Writer = buf
+
+	subCmd := cli.Command{
+		Name:  "bar",
+		Usage: "does bar things",
+	}
+	cmd := cli.Command{
+		Name:        "foo",
+		Description: "foo commands",
+		Subcommands: []cli.Command{subCmd},
+	}
+	app.Commands = []cli.Command{cmd}
+
+	err := app.Run([]string{"command", "foo", "bar", "--help"})
+	if err != nil {
+		t.Error(err)
+	}
+
+	output := buf.String()
+	if !strings.Contains(output, "foo bar - does bar things") {
+		t.Errorf("expected full path to subcommand: %s", output)
+	}
+	if !strings.Contains(output, "command foo bar [arguments...]") {
+		t.Errorf("expected full path to subcommand: %s", output)
+	}
+}
+
 func TestApp_Run_Help(t *testing.T) {
 	var helpArguments = [][]string{{"boom", "--help"}, {"boom", "-h"}, {"boom", "help"}}
 

command.go

@@ -36,11 +36,21 @@ type Command struct {
 	SkipFlagParsing bool
 	// Boolean to hide built-in help command
 	HideHelp bool
+
+	commandNamePath []string
+}
+
+// Returns the full name of the command.
+// For subcommands this ensures that parent commands are part of the command path
+func (c Command) FullName() string {
+	if c.commandNamePath == nil {
+		return c.Name
+	}
+	return strings.Join(c.commandNamePath, " ")
 }
 
 // Invokes the command given the context, parses ctx.Args() to generate command-specific flags
 func (c Command) Run(ctx *Context) error {
-
 	if len(c.Subcommands) > 0 || c.Before != nil || c.After != nil {
 		return c.startApp(ctx)
 	}
@@ -179,5 +189,12 @@ func (c Command) startApp(ctx *Context) error {
 		app.Action = helpSubcommand.Action
 	}
 
+	var newCmds []Command
+	for _, cc := range app.Commands {
+		cc.commandNamePath = []string{c.Name, cc.Name}
+		newCmds = append(newCmds, cc)
+	}
+	app.Commands = newCmds
+
 	return app.RunAsSubcommand(ctx)
 }

help.go

@@ -38,10 +38,10 @@ COPYRIGHT:
 // cli.go uses text/template to render templates. You can
 // render custom help text by setting this variable.
 var CommandHelpTemplate = `NAME:
-   {{.Name}} - {{.Usage}}
+   {{.FullName}} - {{.Usage}}
 
 USAGE:
-   command {{.Name}}{{if .Flags}} [command options]{{end}} [arguments...]{{if .Description}}
+   command {{.FullName}}{{if .Flags}} [command options]{{end}} [arguments...]{{if .Description}}
 
 DESCRIPTION:
    {{.Description}}{{end}}{{if .Flags}}