[vidigoat]

What type of PR is this?

• bug

What this PR does / why we need it:

A flag with an env var but no usage text printed its env var hint one column to the right of the other flags' usage:

cmd := &cli.Command{
	Name: "app",
	Flags: []cli.Flag{
		&cli.StringFlag{Name: "token", Sources: cli.EnvVars("APP_TOKEN")},
		&cli.StringFlag{Name: "name", Usage: "your name", Sources: cli.EnvVars("APP_NAME")},
		&cli.BoolFlag{Name: "quiet", Sources: cli.EnvVars("APP_QUIET")},
	},
}

GLOBAL OPTIONS:
   --token string   [$APP_TOKEN]
   --name string   your name [$APP_NAME]
   --quiet          [$APP_QUIET]
   --help, -h      show help

stringifyFlag passes "<names>\t<usage>" to FlagEnvHinter, and withEnvHint appends " [$APP_TOKEN]". With no usage, that space is the first thing in the usage column, which the tabwriter aligns. stringifyFlag already trims the space in front of (default: …) for the same case (strings.TrimSpace(usage + defaultValueString)), but the env hint is added after that.

• docs.go: withEnvHint leaves out the leading space when the string it is given ends with the tab, i.e. the flag has no usage text. A custom FlagEnvHinter gets the same string as before.
• flag_test.go: TestFlagEnvHintWithoutUsage checks a string flag and a bool flag with two env vars, building the expected hint with withEnvHint so it holds for the Windows %VAR% form too. TestFlagDefaultValueWithEnv and the *WithEnvVarHelpOutput tests built their expected strings by concatenating withEnvHint(envVars, ""), which assumes the hint always starts with a space. They now pass the flag's text to withEnvHint (withEnvHint([]string{"uflag"}, "--flag\t")), or compare against the hint without its leading space.

With this change:

GLOBAL OPTIONS:
   --token string  [$APP_TOKEN]
   --name string   your name [$APP_NAME]
   --quiet         [$APP_QUIET]
   --help, -h      show help

Which issue(s) this PR fixes:

None, found while checking the help output of flags with value sources.

Testing

• TestFlagEnvHintWithoutUsage fails on main ("--token string\t [$APP_TOKEN]") and passes with this change.
• make all, make test GFLAGS='--tags urfave_cli_no_template', make lint, make diffcheck and make v3diff pass, and so do the urfave_cli_no_docs and urfave_cli_no_suggest tags.
• The example CLI built for linux/amd64 with Go 1.27.3 grows by 80 bytes.

Release Notes

In help, the env var hint of a flag with no usage text now lines up with the other flags' usage.

🤖 Generated with Claude Code