Display --help Suggestion Every Time an Error Occurs

[danielhelfand]

I am wondering what the best practice would be for displaying a suggestion to run --help would be after every error message without displaying usage. I would like it for the suggestion to be specific to the root command and subcommands ran.

An example would be that a user types a wrong command or misuses a command. The resulting message would be:

Run rootcommand subcommand --help for usage.

[umarcor]

Hi @danielhelfand! This is partially addressed in #841 and #842 (draft). Precisely, error messages are enhanced to properly identify the following contexts:

"invalid":    `invalid argument "a" for "c"`,
"unknown":    `unknown command "one" for "c"`,
"less":       "requires at least 2 arg(s), only received 1",
"more":       "accepts at most 2 arg(s), received 3",
"notexact":   "accepts 2 arg(s), received 3",
"notinrange": "accepts between 2 and 4 arg(s), received 1",

Then, in #842 generation of help/usage is reworked. See function helpHint.

It'd be great if you could have a look or try them and suggest any enhancement.

[danielhelfand]

@umarcor Thanks for all this information! I'll take a look and keep up with these updates. This looks great so far though. Glad to see this is being worked on.

[github-actions]

This issue is being marked as stale due to a long period of inactivity

[johnSchnake]

If you want a custom usage message you can achieve that as well; you could gather the parent commands names by just walking up the command tree too:

	cmd.SetUsageFunc(func(c *cobra.Command) error {
		current := c
		cmds := []string{c.Name()}
		for{
			if current.HasParent(){
				current= c.Parent()
			}else{
				break
			}
			cmds = append(cmds, current.Name())
		}
		fmt.Printf(`Try "%v --help" for more info`,strings.Join(cmds, " ") )
		return nil
	},

Just one way to do it.

Based on time/activity I'm going to close as motivated by #1600. Reopen if you feel something else needs done here.