[vidigoat]

What type of PR is this?

• bug

What this PR does / why we need it:

With UseShortOptionHandling, a short flag that is missing its argument is reported with its dash on its own, but without it inside a group:

$ app -n           flag needs an argument: -n
$ app -avn         flag needs an argument: n
$ app -nv          flag needs an argument: n    (-n takes a value but isn't last)

TestParseAndRunShortOpts shows both forms next to each other (test -i expects -i, test -ia expects i). v2.27.7 printed -n for -n and -avn, and the other parse errors also name the flag with a dash (flag provided but not defined: -invalid). The two group paths in parseFlags now format it as -%c, like the single-flag path.

Which issue(s) this PR fixes:

None, found by running the same command lines against v2.27.7 and v3.

Testing

• The three -ia/-aic cases in TestParseAndRunShortOpts and TestCommand_UseShortOptionHandlingMultiByteLastFlag now expect the dash; they fail on main.
• Rechecked -avn, -ac and -n against v2.27.7: same messages now.
• make (generate, vet, tests, binary size, gfmrun), make lint and make v3diff pass. go test -race passes, as do the tests with urfave_cli_no_template, urfave_cli_no_docs and urfave_cli_no_suggest.

The change and the test updates were written with Claude Code (AI).

Release Notes

A short flag missing its argument inside a group of short options is now reported with its dash ("flag needs an argument: -n"), as for a single flag.

🤖 Generated with Claude Code

[Juneezee]

Thanks! The fix is right and minimal. I updated one sentence in the description: v2.27.7 gave no error for -nv, because it took -v as the value of -n.