Add ES6 map support to Jasmine

spec/helpers/checkForMap.js

@@ -0,0 +1,22 @@
+(function(env) {
+  function hasFunctioningMaps() {
+    if (typeof Map === 'undefined') { return false; }
+
+    try {
+      var s = new Map([['a', 4]]);
+      if (s.size !== 1) { return false; }
+      if (s.keys().next().value !== 'a') { return false; }
+      if (s.values().next().value !== 4) { return false; }
+      return true;
+    } catch(e) {
+      return false;
+    }
+  }
+
+  env.requireFunctioningMaps = function() {
+    if (!hasFunctioningMaps()) {
+      env.pending("Browser has incomplete or missing support for Maps");
+    }
+  };
+
+})(jasmine.getEnv());