Re: [PATCH v2 2/3] Adjust stat width calculations to take --graph output into account
- From
Lucian Poston <lucian.poston@gmail.com>
- Date
- Apr 12, 2012, 07:47 UTC
- Message-ID
- <CACz_eyc0AjvU0U2FGzqhUTZ_nncuFoAxZ6VGw0=7LVXH4SLqwA@mail.gmail.com>
- In-Reply-To
- <4F6C4C90.5050702@in.waw.pl>
On Fri, Mar 23, 2012 at 03:12, Zbigniew Jędrzejewski-Szmek <zbyszek@in.waw.pl> wrote:
Show 25 quoted lines
> On 03/23/2012 06:54 AM, Lucian Poston wrote:
>
>> diff --git a/diff.c b/diff.c
>> index 377ec1e..31ba10c 100644
>> --- a/diff.c
>> +++ b/diff.c
>> @@ -1383,6 +1383,8 @@ static void show_stats(struct diffstat_t *data, struct diff_options *options)
>> int width, name_width, graph_width, number_width = 4, count;
>> const char *reset, *add_c, *del_c;
>> const char *line_prefix = "";
>> + int line_prefix_length = 0;
>> + int reserved_character_count;
>> int extra_shown = 0;
>> struct strbuf *msg = NULL;
>>
>> @@ -1392,6 +1394,7 @@ static void show_stats(struct diffstat_t *data, struct diff_options *options)
>> if (options->output_prefix) {
>> msg = options->output_prefix(options, options->output_prefix_data);
>> line_prefix = msg->buf;
>> + line_prefix_length = options->output_prefix_length;
>> }
> Hi,
> line_prefix will only be used once. And options->output_prefix_length will
> be 0 if !options->output_prefix, so line_prefix variable can be eliminated
> and options->output_prefix_length used directly instead.Rather than adding the line_prefix_length variable, the next patch will use options->output_prefix_length directly.
Show 67 quoted lines
>> count = options->stat_count ? options->stat_count : data->nr; >> @@ -1427,37 +1430,46 @@ static void show_stats(struct diffstat_t *data, struct diff_options *options) >> * We have width = stat_width or term_columns() columns total. >> * We want a maximum of min(max_len, stat_name_width) for the name part. >> * We want a maximum of min(max_change, stat_graph_width) for the +- part. >> - * We also need 1 for " " and 4 + decimal_width(max_change) >> - * for " | NNNN " and one the empty column at the end, altogether >> + * Each line needs space for the following characters: >> + * - 1 for the initial " " >> + * - 4 + decimal_width(max_change) for " | NNNN " >> + * - 1 for the empty column at the end, >> + * Altogether, the reserved_character_count totals >> * 6 + decimal_width(max_change). >> * >> - * If there's not enough space, we will use the smaller of >> - * stat_name_width (if set) and 5/8*width for the filename, >> - * and the rest for constant elements + graph part, but no more >> - * than stat_graph_width for the graph part. >> - * (5/8 gives 50 for filename and 30 for the constant parts + graph >> - * for the standard terminal size). >> + * Additionally, there may be a line_prefix, which reduces the available >> + * width by line_prefix_length. >> + * >> + * If there's not enough space, we will use the smaller of stat_name_width >> + * (if set) and 5/8*width for the filename, and the rest for the graph >> + * part, but no more than stat_graph_width for the graph part. >> + * Assuming the line prefix is empty, on a standard 80 column terminal >> + * this ratio results in 50 characters for the filename and 20 characters >> + * for the graph (plus the 10 reserved characters). >> * >> * In other words: stat_width limits the maximum width, and >> * stat_name_width fixes the maximum width of the filename, >> * and is also used to divide available columns if there >> * aren't enough. >> */ >> + reserved_character_count = 6 + number_width; >> >> if (options->stat_width == -1) >> width = term_columns(); >> else >> width = options->stat_width ? options->stat_width : 80; >> >> + width -= line_prefix_length; >> + >> if (options->stat_graph_width == -1) >> options->stat_graph_width = diff_stat_graph_width; >> >> /* >> - * Guarantee 3/8*16==6 for the graph part >> - * and 5/8*16==10 for the filename part >> + * Guarantees at least 6 characters for the graph part [16 * 3/8] >> + * and at least 10 for the filename part [16 * 5/8] >> */ >> - if (width< 16 + 6 + number_width) >> - width = 16 + 6 + number_width; >> + if (width< 16 + reserved_character_count) >> + width = 16 + reserved_character_count; >> >> /* >> * First assign sizes that are wanted, ignoring available width. >> @@ -1472,16 +1484,36 @@ static void show_stats(struct diffstat_t *data, struct diff_options *options) >> /* >> * Adjust adjustable widths not to exceed maximum width >> */ > > In this part below, you add gratuitous braces around single line if-blocks. > This makes the code (and the diff) longer with no gain.
I prefer gratuitous braces, particularly when conditionals are nested as they are here. It helps later when maintaining the code if someone wants to add a debug statement or comment out a line.
I'll remove braces from single line conditionals to keep with the existing conventions.
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>> - if (name_width + number_width + 6 + graph_width> width) {
>> - if (graph_width> width * 3/8 - number_width - 6)
>> - graph_width = width * 3/8 - number_width - 6;
>> + if (reserved_character_count + name_width + graph_width> width) {
>> + /*
>> + * Reduce graph_width to be at most 3/8 of the unreserved space and no
>> + * less than 6, which leaves at least 5/8 for the filename.
>> + */
>> + if (graph_width> width * 3/8 - reserved_character_count) {
>> + graph_width = width * 3/8 - reserved_character_count;
>> + if (graph_width< 6) {
>> + graph_width = 6;
>> + }
>> + }
> This extra test is not necessary. Above, after /* Guarantees at least 6 characters
> for the graph part [16 * 3/8] ... */, this should already by so that
> (width * 3/8 - reserved_character_count) is at least 6.Ahh, this is because the calculations go haywire when the number of columns is small. I briefly mentioned it here: http://thread.gmane.org/gmane.comp.version-control.git/193694/focus=193744
graph_width actually can have a negative value under certain conditions, and this check compensates for that edge case. My earlier patches took a less conservative approach and adjusted the calculations so that the value of graph_width would be at least 6, but it caused several tests to regress. Since the intention of the original graph_width calculation was place a lower bound of 6 on its value, I simply enforce that here without affecting the general cases, which will remain unmodified in order to prevent test regressions.
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>> +
>> + /*
>> + * If the remaining unreserved space will not accomodate the
>> + * filenames, adjust name_width to use all available remaining space.
>> + * Otherwise, assign any extra space to graph_width.
>> + */
>> + if (name_width> width - reserved_character_count - graph_width) {
>> + name_width = width - reserved_character_count - graph_width;
>> + } else {
>> + graph_width = width - reserved_character_count - name_width;
>> + }
>> +
>> + /*
>> + * If stat-graph-width was specified, limit graph_width to its value.
>> + */
>> if (options->stat_graph_width&&
>> - graph_width> options->stat_graph_width)
>> + graph_width> options->stat_graph_width) {
>> graph_width = options->stat_graph_width;
>> - if (name_width> width - number_width - 6 - graph_width)
>> - name_width = width - number_width - 6 - graph_width;
>> - else
>> - graph_width = width - number_width - 6 - name_width;
>> + }
> Here, the order of the two tests
> (1) if (options->stat_graph_width && graph_width > options->stat_graph_width)
> (2) if (name_width > width - number_width - 6 - graph_width)
> is reversed. This is not OK, because this means that
> options->stat_graph_width will be used unconditionally, while
> before it was subject to limiting by total width.If options->stat_graph_width is specified, it should always limit the value of graph_width, correct? Since (1) is the last test, it can only decrease the value of graph_width, which would already be limited by the total width.
I just noticed that name_width isn't being limited to stat_name_width, if it is specified. I'll add a check for that.
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> The tests: > After the new tests are added, I see: > > ok 53 - format-patch ignores COLUMNS (long filename) > ok 54 - diff respects COLUMNS (long filename) > ok 55 - show respects COLUMNS (long filename) > ok 56 - log respects COLUMNS (long filename) > ok 57 - show respects 80 COLUMNS (long filename) <======= > ok 58 - log respects 80 COLUMNS (long filename) <------- > ok 59 - show respects 80 COLUMNS (long filename) <======= > ok 60 - log respects 80 COLUMNS (long filename) <------- > > So some tests descriptions are duplicated. Also it would be > nice to test with --graph in more places. I'm attaching a > replacement patch which adds more tests. It should go *before* > your series, and your series should tweak the tests to pass, > showing what changed.
Thanks, I'll add these.