use lts range instead of latest

lib/binaries.sh

@@ -35,11 +35,12 @@ install_yarn() {
 }
 
 install_nodejs() {
-  local version="$1"
+  local user_version="$1"
   local dir="$2"
+  local version=${user_version:-6.x}
 
   if needs_resolution "$version"; then
-    echo "Resolving node version ${version:-(latest stable)} via semver.io..."
+    echo "Resolving node version $version via semver.io..."
     local version=$(curl --silent --get --retry 5 --retry-max-time 15 --data-urlencode "range=${version}" https://semver.herokuapp.com/node/resolve)
   fi
 

test/run

 #!/usr/bin/env bash
 # See README.md for info on running these tests.
 
+testNoVersion() {
+  compile "no-version"
+  assertCaptured "engines.node (package.json):  unspecified"
+  assertCaptured "Resolving node version 6.x via semver.io"
+  assertCaptured "Downloading and installing node 6."
+  assertCapturedSuccess
+}
+
 testDisableCache() {
   cache=$(mktmpdir)
   env_dir=$(mktmpdir)
@@ -300,14 +308,6 @@ testIoJs() {
   assertCapturedSuccess
 }
 
-testNoVersion() {
-  compile "no-version"
-  assertCaptured "engines.node (package.json):  unspecified"
-  assertCaptured "Resolving node version (latest stable) via semver.io"
-  assertCaptured "Downloading and installing node 6."
-  assertCapturedSuccess
-}
-
 testSpecificVersion() {
   compile "specific-version"
   assertNotCaptured "Resolving node version"