Merge pull request #1676 from Quadric/fix-node-version-in-install-script

`install.sh`: Fix a bug that block that installation of node in install.sh
diff --git a/install.sh b/install.sh
index e0d793e..120c98a 100755
--- a/install.sh
+++ b/install.sh
@@ -140,22 +140,22 @@
 # Automatically install Node.js
 #
 nvm_install_node() {
-  local NODE_VERSION
-  NODE_VERSION="$(nvm_node_version)"
+  local NODE_VERSION_LOCAL
+  NODE_VERSION_LOCAL="$(nvm_node_version)"
 
-  if [ -z "$NODE_VERSION" ]; then
+  if [ -z "$NODE_VERSION_LOCAL" ]; then
     return 0
   fi
 
-  echo "=> Installing Node.js version $NODE_VERSION"
-  nvm install "$NODE_VERSION"
+  echo "=> Installing Node.js version $NODE_VERSION_LOCAL"
+  nvm install "$NODE_VERSION_LOCAL"
   local CURRENT_NVM_NODE
 
   CURRENT_NVM_NODE="$(nvm_version current)"
-  if [ "$(nvm_version "$NODE_VERSION")" == "$CURRENT_NVM_NODE" ]; then
-    echo "=> Node.js version $NODE_VERSION has been successfully installed"
+  if [ "$(nvm_version "$NODE_VERSION_LOCAL")" == "$CURRENT_NVM_NODE" ]; then
+    echo "=> Node.js version $NODE_VERSION_LOCAL has been successfully installed"
   else
-    echo >&2 "Failed to install Node.js $NODE_VERSION"
+    echo >&2 "Failed to install Node.js $NODE_VERSION_LOCAL"
   fi
 }
 
diff --git a/test/install_script/nvm_install_with_node_version b/test/install_script/nvm_install_with_node_version
new file mode 100755
index 0000000..5f5208f
--- /dev/null
+++ b/test/install_script/nvm_install_with_node_version
@@ -0,0 +1,8 @@
+#!/bin/sh
+
+die () { echo "$@" ; exit 1; }
+
+NODE_VERSION=8 \. ../../install.sh
+
+# nvm installed node 8
+nvm ls 8 > /dev/null 2>&1 || die "nvm didn't install node 8"