Allow helperMissing to apply to simple mustaches (paves the way to support things like link_to in a Rails context)

spec/qunit_spec.js

@@ -1,5 +1,11 @@
 module("basic context");
 
+Handlebars.registerHelper('helperMissing', function(helper, context) {
+  if(helper === "link_to") {
+    return new Handlebars.SafeString("<a>" + context + "</a>");
+  }
+});
+
 var shouldCompileTo = function(string, hash, expected, message) {
   var template = Handlebars.compile(string);
   if(Object.prototype.toString.call(hash) === "[object Array]") {
@@ -459,3 +465,11 @@ test("constructing a safestring from a string and checking its type", function()
   equal(safe, "testing 1, 2, 3", "SafeString is equivalent to its underlying string");
 });
 
+module("helperMissing");
+
+test("if a context is not found, helperMissing is used", function() {
+  var string = "{{hello}} {{link_to world}}"
+  var context = { hello: "Hello", world: "world" };
+
+  shouldCompileTo(string, context, "Hello <a>world</a>")
+})