Re: orthogonal cases of log --date option

[Junio C Hamano <gitster@pobox.com>]

Jay Soffian <jaysoffian@gmail.com> writes:

> On Fri, Mar 6, 2009 at 1:50 AM, Junio C Hamano <gitster@pobox.com> wrote:
>> Jeff King <peff@peff.net> writes:
>>
>>> Because from the user's perspective --foo={bar,baz,bleep} is about
>>> selecting exactly one of {bar,baz,bleep}.
>>
>> I do not feel very strongly about this either way, and without any prior
>> end user "Huh?" input, I would probably have argued like you myself, but
>> I saw the original message from Miles about giving more than one --date
>> and getting perplexed to see that it did not work, so...
>>
>> I am not likely to use --tz=Indian/Christmas myself; GMT and local might
>> however be useful in some situations, though.
>
> So I don't mind picking this up, but I'd like some guidance. There are
> two issues:
>
> 1) The CLI. You and Jeff don't seem to have an agreement here, but
> frankly, this is the easy part.
>
> 2) The internal implementation. Your implementation (enum -> bitfield)
> is clever, but Jeff seems to prefer what I suggested (going to a
> struct). The latter is quite a bit more work.

Is it?  Isn't it just the matter of doing something like this?

	struct date_mode {
        	enum {
                DATE_NORMAL = 0,
                DATE_RELATIVE,
                ...
                DATE_RAW
                } format;
                enum {
                DATE_ORIGINAL = 0,
                DATE_LOCAL
                /* perhaps ",DATE_GMT" later... */
                } tz_offset;
	};

	/* In revision.c::handle_revision_opt() */
        ...
	} else if (!strcmp(arg, "--date=local")) {
		revs->date_mode.format = DATE_NORMAL;
        	revs->date_mode.tz_offset = DATE_LOCAL;
	} else if (!prefixcmp(arg, "--date=")) {
        	revs->date_mode.format = parse_date_format(arg + 7);
	} else if (!strcmp(arg, "--tz=local")) {
        	revs->date_mode.tz_offset = DATE_LOCAL;
	}
	...

        /* In date.c::show_date() */
	...
        const char *show_date(unsigned long time, int tz, struct date_mode *mode_)
	{
        	int mode = mode_->format;

		if (mode_->tz_offset == DATE_LOCAL)
			tz = local_tzoffset(time);

		...
		/* and remove the existing
                if (mode == DATE_LOCAL)
                	tz = local_tzoffset(time);
		   that appears later in the code
		*/
	...