Subject: Re: [PATCH 01/11] graph: automatically track visible width of `strbuf`

From: Denton Liu <[email-masked]>
Date: Thu, 10 Oct 2019 22:01:11 -0700

On Fri, Oct 11, 2019 at 10:42:20AM +0900, Junio C Hamano wrote:
> Denton Liu <[email-masked]> writes:
> 
> > 	static int calculate_width(const struct strbuf *row)
> > 	{
> > 		int in_termcode = 0;
> > 		int width = 0;
> > 		int i;
> >
> > 		for (i = 0; i < row.len; i++) {
> > 			if (row.buf[i] == '\033')
> > 				in_termcode = 1;
> >
> > 			if (!in_termcode)
> > 				width++;
> > 			else if (row.buf[i] == 'm')
> > 				in_termcode = 0;
> > 		}
> > 	}
> 
> Not every byte that is outside the escape sequence contributes to
> one display columns.  You would want to take a look at utf8_width()
> for inspiration.
> 

Heh, I guess you're right. Looking right below the definition of
utf8_width, I realised we have the utf8_strnwidth function. We should be
able to just call

	utf8_strnwidth(row.buf, row.len, 1);