Wrong help output when a Command has "HideHelpCommand=true" but no defined subcommands

[fsufitch]

My urfave/cli version is

v2.27.1

Checklist

• Are you running the latest v2 release? The list of releases is here.
• Did you check the manual for your release? The v2 manual is here
• Did you perform a search about this problem? Here's the GitHub guide about searching.

Dependency Management

• My project is automatically downloading the latest version.

Describe the bug

When HideHelpCommand is set to true on a command with no subcommands, the help text output by [...] mycmd --help imples there are subcommands, when in fact there are none. By comparison, the text output by [...] help mycmd is correct, though!

To reproduce

package main

import (
	"fmt"

	"github.com/urfave/cli/v2"
)

func main() {
	app := &cli.App{Commands: []*cli.Command{{
		Name:            "foo",
		HideHelpCommand: true, // <--- problem is here
	}}}

	app.Run([]string{"CMD", "help", "foo"})

	fmt.Print("\n\n========================================\n\n")

	app.Run([]string{"CMD", "foo", "--help"})
}

Observed behavior

The former execution presents the usage:

play foo [command options] [arguments...]

While the latter presents the (incorrect) usage:

play foo command [command options]

Expected behavior

The two outputs should match. The help calls are equivalent, and the latter output is misleading.

Additional context

Playground of the broken code: https://go.dev/play/p/kCuTCXk3Uxg

Run go version and paste its output here

N/A (Go 1.22 in the Go Playground)

Run go env and paste its output here

N/A (Go 1.22 in the Go Playground)