diff --git a/executable/Env.re b/executable/Env.re
index 6881331..792890f 100644
--- a/executable/Env.re
+++ b/executable/Env.re
@@ -78,7 +78,7 @@ let printUseOnCd = (~shell) =>
   switch (shell) {
   | System.Shell.Bash => {|
     __fnmcd () {
-      cd $@
+      cd "$@"
 
       if [[ -f .node-version && .node-version ]]; then
         echo "fnm: Found .node-version"
diff --git a/feature_tests/run.sh b/feature_tests/run.sh
index 8ecdcb4..2aef50a 100755
--- a/feature_tests/run.sh
+++ b/feature_tests/run.sh
@@ -2,8 +2,9 @@
 
 set -e
 
-DIRECTORY=`dirname $0`
-BINARY=$1
+DIRECTORY="$(dirname "$0")"
+BINARY="$1"
+SPECIFIC_TEST="$2"
 TEMP_DIR_BASE=$(pwd)/$DIRECTORY/.tmp
 TEMP_BINARY_PATH=$TEMP_DIR_BASE/bin
 TEMP_FNM_DIR=$TEMP_DIR_BASE/.fnm
@@ -15,18 +16,30 @@ fi
 
 echo "using fnm=$BINARY"
 
-rm -rf $TEMP_DIR_BASE
-mkdir $TEMP_DIR_BASE $TEMP_BINARY_PATH
-cp $BINARY $TEMP_BINARY_PATH/fnm
+rm -rf "$TEMP_DIR_BASE"
+mkdir "$TEMP_DIR_BASE" "$TEMP_BINARY_PATH"
+cp "$BINARY" "$TEMP_BINARY_PATH/fnm"
 
-for test_file in $DIRECTORY/*/run.sh; do
-  rm -rf $TEMP_FNM_DIR
+run_test() {
+  test_file="$1"
+  rm -rf "$TEMP_FNM_DIR"
+
+  TEST_BASENAME="$(basename "$test_file")"
+  TEST_DIRNAME="$(dirname "$test_file")"
 
   echo "Running test in $test_file"
   echo "Running test in $test_file" | sed "s/./-/g"
-  (cd $(dirname $test_file) && FNM_DIR=$TEMP_FNM_DIR PATH=$TEMP_BINARY_PATH:$PATH bash $(basename $test_file))
+  (cd "$TEST_DIRNAME" && FNM_DIR="$TEMP_FNM_DIR" PATH="$TEMP_BINARY_PATH:$PATH" bash "$TEST_BASENAME")
   echo ""
   echo " -> Finished!"
 
-  rm -rf $TEMP_FNM_DIR
-done
+  rm -rf "$TEMP_FNM_DIR"
+}
+
+if [ "$SPECIFIC_TEST" == "" ]; then
+  for test_file in "$DIRECTORY"/*/run.sh; do
+    run_test "$test_file"
+  done
+else
+  run_test "$SPECIFIC_TEST"
+fi
diff --git a/feature_tests/use_on_cd/dot_node_version/.node-version b/feature_tests/use_on_cd/dot node version/.node-version
similarity index 100%
rename from feature_tests/use_on_cd/dot_node_version/.node-version
rename to feature_tests/use_on_cd/dot node version/.node-version
diff --git a/feature_tests/use_on_cd/run.sh b/feature_tests/use_on_cd/run.sh
index 179ebe8..d89db2d 100644
--- a/feature_tests/use_on_cd/run.sh
+++ b/feature_tests/use_on_cd/run.sh
@@ -2,9 +2,7 @@
 
 set -e
 
-DIRECTORY=`dirname $0`
-
-eval "`fnm env --multi`"
+eval "$(fnm env --multi)"
 fnm install 6.11.3
 fnm install 8.11.3
 fnm use 6.11.3
@@ -34,7 +32,7 @@ if hash zsh 2>/dev/null; then
     fi
 
     fnm use 6.11.3
-    cd ../dot_node_version
+    cd ../dot\ node\ version
 
     NODE_VERSION=$(node -v)
     if [ "$NODE_VERSION" != "v8.11.3" ]; then
@@ -69,7 +67,7 @@ if hash fish 2>/dev/null; then
     end
 
     fnm use 6.11.3
-    cd ../dot_node_version
+    cd ../dot\ node\ version
 
     set NODE_VERSION (node -v)
     if test "$NODE_VERSION" != "v8.11.3"
@@ -83,6 +81,7 @@ fi
 
 echo " > Running test on Bash..."
 bash -c '
+  set -e
   shopt -s expand_aliases
   eval "`fnm env --multi --use-on-cd`"
   fnm use 6.11.3
@@ -98,7 +97,7 @@ bash -c '
     exit 1
   fi
   fnm use 6.11.3
-  cd ../dot_node_version
+  cd ../dot\ node\ version
   NODE_VERSION=$(node -v)
   if [ "$NODE_VERSION" != "v8.11.3" ]; then
     echo "Failed: Node version ($NODE_VERSION) is not v8.11.3"