diff --stat: add config option to limit graph width

Config option diff.statGraphWidth=<width> is equivalent to
--stat-graph-width=<width>, except that the config option is ignored
by format-patch.

For the graph-width limiting to be usable, it should happen
'automatically' once configured, hence the config option.
Nevertheless, graph width limiting only makes sense when used on a
wide terminal, so it should not influence the output of format-patch,
which adheres to the 80-column standard.

Signed-off-by: Zbigniew Jędrzejewski-Szmek <zbyszek@in.waw.pl>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 8 insertions, 0 deletions

diff --git a/diff.c b/diff.c
index 8f2abc8..4525cda 100644
--- a/diff.c
+++ b/diff.c
@@ -31,6 +31,7 @@ static const char *external_diff_cmd_cfg;
 int diff_auto_refresh_index = 1;
 static int diff_mnemonic_prefix;
 static int diff_no_prefix;
+static int diff_stat_graph_width;
 static int diff_dirstat_permille_default = 30;
 static struct diff_options default_diff_options;
 
@@ -156,6 +157,10 @@ int git_diff_ui_config(const char *var, const char *value, void *cb)
 		diff_no_prefix = git_config_bool(var, value);
 		return 0;
 	}
+	if (!strcmp(var, "diff.statgraphwidth")) {
+		diff_stat_graph_width = git_config_int(var, value);
+		return 0;
+	}
 	if (!strcmp(var, "diff.external"))
 		return git_config_string(&external_diff_cmd_cfg, var, value);
 	if (!strcmp(var, "diff.wordregex"))
@@ -1398,6 +1403,9 @@ static void show_stats(struct diffstat_t *data, struct diff_options *options)
 	else
 		width = options->stat_width ? options->stat_width : 80;
 
+	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