diff --git a/run-tests.sh b/run-tests.sh
index e39418fb354226b767aedf5c7d1de462707bdf5e..1a5be572416c6f6794a4f7d1ce108423aebfdc35 100755
--- a/run-tests.sh
+++ b/run-tests.sh
@@ -8,7 +8,7 @@ for f in testcases/regression/valid/*.scala; do
   echo -n "Running $f, expecting VALID, got: "
   res=`./leon --noLuckyTests --timeout=10 --oneline "$f"`
   echo $res | tr [a-z] [A-Z]
-  if [ $res = valid ]; then
+  if [ "$res" = valid ]; then
     nbsuccess=$((nbsuccess + 1))
   else
     failedtests="$failedtests $f"
@@ -19,7 +19,7 @@ for f in testcases/regression/invalid/*.scala; do
   echo -n "Running $f, expecting INVALID, got: "
   res=`./leon --noLuckyTests --timeout=10 --oneline "$f"`
   echo $res | tr [a-z] [A-Z]
-  if [ $res = invalid ]; then
+  if [ "$res" = invalid ]; then
     nbsuccess=$((nbsuccess + 1))
   else
     failedtests="$failedtests $f"
@@ -30,7 +30,7 @@ for f in testcases/regression/error/*.scala; do
   echo -n "Running $f, expecting ERROR, got: "
   res=`./leon --noLuckyTests --timeout=10 --oneline "$f"`
   echo $res | tr [a-z] [A-Z]
-  if [ $res = error ]; then
+  if [ "$res" = error ]; then
     nbsuccess=$((nbsuccess + 1))
   else
     failedtests="$failedtests $f"