Add unit test for plugin

components/servo/Cargo.lock

@@ -1280,6 +1280,7 @@ name = "util_tests"
 version = "0.0.1"
 dependencies = [
  "geom 0.1.0 (git+https://github.com/servo/rust-geom)",
+ "plugins 0.0.1",
  "util 0.0.1",
 ]
 

tests/unit/util/Cargo.toml

@@ -11,5 +11,9 @@ doctest = false
 [dependencies.util]
 path = "../../../components/util"
 
+
+[dependencies.plugins]
+path = "../../../components/plugins"
+
 [dependencies.geom]
 git = "https://github.com/servo/rust-geom"

tests/unit/util/lib.rs

@@ -2,6 +2,8 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
+#![feature(plugin, custom_derive, custom_attributes)]
+#![plugin(plugins)]
 extern crate util;
 extern crate geom;
 
@@ -9,3 +11,4 @@ extern crate geom;
 #[cfg(test)] mod logical_geometry;
 #[cfg(test)] mod task;
 #[cfg(test)] mod vec;
+#[cfg(test)] mod mem;

tests/unit/util/mem.rs

@@ -0,0 +1,33 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+use util::mem::HeapSizeOf;
+
+
+struct Four;
+impl HeapSizeOf for Four {
+    fn heap_size_of_children(&self) -> usize {
+        4
+    }
+}
+
+#[derive(HeapSizeOf)]
+struct Eight(Four, Four, bool, bool, bool);
+
+#[derive(HeapSizeOf)]
+enum EightOrFour {
+    Eight(Eight),
+    Four(Four),
+    Zero(u8)
+}
+
+#[test]
+fn test_heap_size() {
+    assert_eq!(Four.heap_size_of_children(), 4);
+    let eight = Eight(Four, Four, true, true, true);
+    assert_eq!(eight.heap_size_of_children(), 8);
+    assert_eq!(EightOrFour::Eight(eight).heap_size_of_children(), 8);
+    assert_eq!(EightOrFour::Four(Four).heap_size_of_children(), 4);
+    assert_eq!(EightOrFour::Zero(1).heap_size_of_children(), 0);
+}