diff --git a/mergetools/vimdiff b/mergetools/vimdiff
index 97e376329b..734d15a03b 100644
--- a/mergetools/vimdiff
+++ b/mergetools/vimdiff
@@ -72,7 +72,6 @@ gen_cmd_aux () {
 	nested=0
 	nested_min=100
 
-
 	# Step 1:
 	#
 	# Increase/decrease "start"/"end" indices respectively to get rid of
@@ -87,7 +86,7 @@ gen_cmd_aux () {
 	IFS=#
 	for c in $(echo "$LAYOUT" | sed 's:.:&#:g')
 	do
-		if test "$c" = " "
+		if test -z "$c" || test "$c" = " "
 		then
 			continue
 		fi
diff --git a/t/t4046-diff-unmerged.sh b/t/t4046-diff-unmerged.sh
index ffaf69335f..fb8c51746e 100755
--- a/t/t4046-diff-unmerged.sh
+++ b/t/t4046-diff-unmerged.sh
@@ -20,13 +20,15 @@ test_expect_success setup '
 			for t in o x
 			do
 				path="$b$o$t" &&
-				case "$path" in ooo) continue ;; esac &&
-				paths="$paths$path " &&
-				p="	$path" &&
-				case "$b" in x) echo "$m1$p" ;; esac &&
-				case "$o" in x) echo "$m2$p" ;; esac &&
-				case "$t" in x) echo "$m3$p" ;; esac ||
-				return 1
+				if test "$path" != ooo
+				then
+					paths="$paths$path " &&
+					p="	$path" &&
+					case "$b" in x) echo "$m1$p" ;; esac &&
+					case "$o" in x) echo "$m2$p" ;; esac &&
+					case "$t" in x) echo "$m3$p" ;; esac ||
+					return 1
+				fi
 			done
 		done
 	done >ls-files-s.expect &&