wrap non-arrays/strings/falsys in an array in util.list - fixes babel/babelify#69

src/babel/util.js

@@ -59,8 +59,10 @@ export function list(val: string): Array<string> {
     return [];
   } else if (Array.isArray(val)) {
     return val;
-  } else {
+  } else if (typeof val === "string") {
     return val.split(",");
+  } else {
+    return [val];
   }
 }
 

test/core/util.js

@@ -58,6 +58,10 @@ suite("util", function () {
     assert.deepEqual(util.list("foo"), ["foo"]);
     assert.deepEqual(util.list("foo,bar"), ["foo", "bar"]);
     assert.deepEqual(util.list(["foo", "bar"]), ["foo", "bar"]);
+    assert.deepEqual(util.list(/foo/), [/foo/]);
+
+    var date = new Date;
+    assert.deepEqual(util.list(date), [date]);
   });
 
   test("arrayify", function () {