Merge branch 'mk/diff-shortstat-dirstat-fix' into maint

"git diff --shortstat --dirstat=changes" showed a dirstat based on
lines that was never asked by the end user in addition to the
dirstat that the user asked for.

* mk/diff-shortstat-dirstat-fix:
  diff --shortstat --dirstat: remove duplicate output

Author: gitster

diff.c

@@ -4541,7 +4541,7 @@ void diff_flush(struct diff_options *options)
 			show_stats(&diffstat, options);
 		if (output_format & DIFF_FORMAT_SHORTSTAT)
 			show_shortstats(&diffstat, options);
-		if (output_format & DIFF_FORMAT_DIRSTAT)
+		if (output_format & DIFF_FORMAT_DIRSTAT && dirstat_by_line)
 			show_dirstat_by_line(&diffstat, options);
 		free_diffstat_info(&diffstat);
 		separator++;

t/t4047-diff-dirstat.sh

@@ -973,4 +973,18 @@ test_expect_success 'diff.dirstat=future_param,0,lines should warn, but still wo
 	test_i18ngrep -q "diff\\.dirstat" actual_error
 '
 
+test_expect_success '--shortstat --dirstat should output only one dirstat' '
+	git diff --shortstat --dirstat=changes HEAD^..HEAD >out &&
+	grep " dst/copy/changed/$" out >actual_diff_shortstat_dirstat_changes &&
+	test_line_count = 1 actual_diff_shortstat_dirstat_changes &&
+
+	git diff --shortstat --dirstat=lines HEAD^..HEAD >out &&
+	grep " dst/copy/changed/$" out >actual_diff_shortstat_dirstat_lines &&
+	test_line_count = 1 actual_diff_shortstat_dirstat_lines &&
+
+	git diff --shortstat --dirstat=files HEAD^..HEAD >out &&
+	grep " dst/copy/changed/$" out >actual_diff_shortstat_dirstat_files &&
+	test_line_count = 1 actual_diff_shortstat_dirstat_files
+'
+
 test_done