Re: [PATCH v2 2/4] stripspace: Use parse-options for command-line parsing

[Tobias Klauser <tklauser@distanz.ch>]

On 2015-10-16 at 19:07:34 +0200, Junio C Hamano <gitster@pobox.com> wrote:
> Tobias Klauser <tklauser@distanz.ch> writes:
> 
> > Use parse-options to parse command-line options instead of a
> > hand-crafted implementation.
> >
> > This is a preparatory patch to simplify the introduction of the
> > --count-lines option in a follow-up patch.
> 
> The second paragraph is probably of much lessor importance than one
> thing you forgot to mention: the users can now use a unique prefix
> of the option and say "stripspace --comment".

I didn't even know about that feature, but now that you've mentioned it
I will certainly make use of it more in the future :) And of course,
I'll adjust the commit message accordingly for v3.

> > +enum stripspace_mode {
> > +	STRIP_DEFAULT = 0,
> > +	STRIP_COMMENTS,
> > +	COMMENT_LINES
> > +};
> >  
> >  int cmd_stripspace(int argc, const char **argv, const char *prefix)
> >  {
> >  	struct strbuf buf = STRBUF_INIT;
> > -	int strip_comments = 0;
> > -	enum { INVAL = 0, STRIP_SPACE = 1, COMMENT_LINES = 2 } mode = STRIP_SPACE;
> > -
> > -	if (argc == 2) {
> > -		if (!strcmp(argv[1], "-s") ||
> > -		    !strcmp(argv[1], "--strip-comments")) {
> > -			strip_comments = 1;
> > -		} else if (!strcmp(argv[1], "-c") ||
> > -			   !strcmp(argv[1], "--comment-lines")) {
> > -			mode = COMMENT_LINES;
> > -		} else {
> > -			mode = INVAL;
> > -		}
> > -	} else if (argc > 1) {
> > -		mode = INVAL;
> > -	}
> > -
> > -	if (mode == INVAL)
> > -		usage(usage_msg);
> 
> When given "git stripspace -s blorg", we used to set mode to INVAL
> and then showed the correct usage.  But we no longer have a check
> that corresponds to the old INVAL thing, do we?  Perhaps check argc
> to detect presence of an otherwise ignored non-option argument
> immediately after parse_options() returns?

Agreed, we should check it. I'll go with the implementation you
suggested in the follow-up message.

> > -	if (strip_comments || mode == COMMENT_LINES)
> > +	enum stripspace_mode mode = STRIP_DEFAULT;
> > +
> > +	const struct option options[] = {
> > +		OPT_CMDMODE('s', "strip-comments", &mode,
> > +			    N_("skip and remove all lines starting with comment character"),
> > +			    STRIP_COMMENTS),
> > +		OPT_CMDMODE('c', "comment-lines", &mode,
> > +			    N_("prepend comment character and blank to each line"),
> > +			    COMMENT_LINES),
> > +		OPT_END()
> > +	};
> > +
> > +	argc = parse_options(argc, argv, prefix, options, stripspace_usage,
> > +			     PARSE_OPT_KEEP_DASHDASH);
> 
> What is the point of keep-dashdash here?

Likewise, it shouldn't be there as in your follow-up patch.