Re: [PATCH v3 01/13] graph: automatically track display width of graph lines

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

"James Coglan via GitGitGadget" <gitgitgadget@gmail.com> writes:

> +struct graph_line {
> +	struct strbuf *buf;
> +	size_t width;
> +};
> +
> +static inline void graph_line_addch(struct graph_line *line, int c)
> +{
> +	strbuf_addch(line->buf, c);
> +	line->width++;
> +}
> +
> +static inline void graph_line_addchars(struct graph_line *line, int c, size_t n)
> +{
> +	strbuf_addchars(line->buf, c, n);
> +	line->width += n;
> +}
> +
> +static inline void graph_line_addstr(struct graph_line *line, const char *s)
> +{
> +	strbuf_addstr(line->buf, s);
> +	line->width += strlen(s);
> +}
> +
> +static inline void graph_line_addcolor(struct graph_line *line, unsigned short color)
> +{
> +	strbuf_addstr(line->buf, column_get_color_code(color));
> +}

All makes sense, and as long as nobody uses strbuf_add*() on
line->buf directly, it shouldn't be too hard to extend these
to support graph drawn characters outside ASCII in the future
after this series settles.

>  static void graph_output_pre_commit_line(struct git_graph *graph,
> ...
>  	for (i = 0; i < graph->num_columns; i++) {
>  		struct column *col = &graph->columns[i];
>  		if (col->commit == graph->commit) {
>  			seen_this = 1;
> -			strbuf_write_column(sb, col, '|');
> -			strbuf_addchars(sb, ' ', graph->expansion_row);
> -			chars_written += 1 + graph->expansion_row;
> +			graph_line_write_column(line, col, '|');
> +			graph_line_addchars(line, ' ', graph->expansion_row);

Nice reduction of noise, as the proposed log message promises.

>  int graph_next_line(struct git_graph *graph, struct strbuf *sb)

I just noticed it but does this have to be extern?  Nobody outside
graph.[ch] seems to have any reference to it.  That might mean that
it may be easier than we thought earlier to change the second
parameter of this to "struct graph_line *", instead of us wrapping
an incoming strbuf (which external callers are aware of, as opposed
to graph_line which we prefer not to expose to outsiders).  Whether
we change the second parameter or not, the first clean-up may be to
turn this function into a file-scope static, perhaps?

All the changes are very pleasing to see.  Thanks.