Re: [PATCH v2 2/3] git.c: handle_alias: prepend alias info when first argument is -h

> Most git commands respond to -h anywhere in the command line, or at
> least as a first and lone argument, by printing the usage
> information. For aliases, we can provide a little more information that
> might be useful in interpreting/understanding the following output by
> prepending a line telling that the command is an alias, and for what.
> 
> When one invokes a simple alias, such as "cp = cherry-pick"
> with -h, this results in
> 
> $ git cp -h
> 'cp' is aliased to 'cherry-pick'
> usage: git cherry-pick [<options>] <commit-ish>...
> ...
> 
> When the alias consists of more than one word, this provides the
> additional benefit of informing the user which options are implicit in
> using the alias, e.g. with "cp = cherry-pick -n":
> 
> $ git cp -h
> 'cp' is aliased to 'cherry-pick -n'
> usage: git cherry-pick [<options>] <commit-ish>...
> ...
> 
> For shell commands, we cannot know how it responds to -h, but printing
> this line to stderr should not hurt, and can help in figuring out what
> is happening in a case like
> 
> $ git sc -h
> 'sc' is aliased to '!somecommand'
> somecommand: invalid option '-h'

> diff --git a/git.c b/git.c
> index a6f4b44af5..0211c2d4c0 100644
> --- a/git.c
> +++ b/git.c
> @@ -318,6 +318,9 @@ static int handle_alias(int *argcp, const char ***argv)
>  	alias_command = (*argv)[0];
>  	alias_string = alias_lookup(alias_command);
>  	if (alias_string) {
> +		if (*argcp > 1 && !strcmp((*argv)[1], "-h"))
> +			fprintf_ln(stderr, _("'%s' is aliased to '%s'"),
> +				   alias_command, alias_string);
>  		if (alias_string[0] == '!') {
>  			struct child_process child = CHILD_PROCESS_INIT;
>  			int nongit_ok;