sort: fix -s -r interaction: 'stable' order is not affected by -r

function                                             old     new   delta
compare_keys                                         818     820      +2

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

coreutils/sort.c

@@ -380,7 +380,9 @@ static int compare_keys(const void *xarg, const void *yarg)
 
 			/* If x > y, 1, else -1 */
 			retval = (x32 > y32) * 2 - 1;
-		} else
+			/* Here, -r has no effect! */
+			return retval;
+		}
 		if (!(option_mask32 & FLAG_no_tie_break)) {
 			/* fallback sort */
 			flags = option_mask32;

testsuite/sort.tests

@@ -175,6 +175,19 @@ testing "sort file in place" \
 111
 " ""
 
+testing "sort -sr (stable and reverse) does NOT reverse 'stable' ordering" \
+"sort -k2 -r -s input" "\
+b 2
+d 2
+a 1
+c 1
+" "\
+a 1
+b 2
+c 1
+d 2
+" ""
+
 # testing "description" "command(s)" "result" "infile" "stdin"
 
 exit $FAILCOUNT