     internal var befores: [BeforeExampleWithMetadataClosure] {
         var closures = Array(hooks.befores.reverse())
         walkUp() { (group: ExampleGroup) -> () in
-            closures.extend(Array(group.hooks.befores.reverse()))
+            closures.appendContentsOf(Array(group.hooks.befores.reverse()))
         }
         return Array(closures.reverse())
     }

    internal var afters: [AfterExampleWithMetadataClosure] {
        var closures = hooks.afters
        walkUp() { (group: ExampleGroup) -> () in
            closures.extend(group.hooks.afters)
        }
        return closures
    }

    public var examples: [Example] {
        var examples = childExamples
        for group in childGroups {
            examples.appendContentsOf(group.examples)
        }
        return examples
    }
