Fix filename.join/2 signature

Mohamed Seleem · Mohamed Seleem · commit a9eae953e66b · 2017-10-22T10:34:02.000+02:00
diff --git a/src/javascript/lib/core/erlang_compat/filename.js b/src/javascript/lib/core/erlang_compat/filename.js
@@ -1,6 +1,5 @@
-function join(arg = [], extra = []) {
-  let components = Array.isArray(arg) ? arg : [arg];
-  components = components.concat(extra)
+function join(arg, extra = null) {
+  const components = Array.isArray(arg) ? arg : [arg, extra];
   let names = [];
   for (let i = components.length - 1; i >= 0; i--) {
     const name = components[i];
diff --git a/src/javascript/tests/core/erlang_compat/filename_spec.js b/src/javascript/tests/core/erlang_compat/filename_spec.js
@@ -19,3 +19,8 @@ test('join/1', (t) => {
   result = Core.filename.join(['a/b///c/']);
   t.is(result, 'a/b/c');
 });
+
+test('join/2', (t) => {
+  let result = Core.filename.join('/usr', 'bin');
+  t.is(result, '/usr/bin');
+});
