Proactive SkPixelRef invalidation

tests/MessageBusTest.cpp

+/*
+ * Copyright 2013 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "SkMessageBus.h"
+#include "Test.h"
+#include "TestClassDef.h"
+
+namespace {
+
+struct TestMessage {
+    int x;
+    float y;
+};
+
+}  // namespace
+
+DEF_TEST(MessageBus, r) {
+    // Register two inboxes to receive all TestMessages.
+    SkMessageBus<TestMessage>::Inbox inbox1, inbox2;
+
+    // Send two messages.
+    const TestMessage m1 = { 5, 4.2f };
+    const TestMessage m2 = { 6, 4.3f };
+    SkMessageBus<TestMessage>::Post(m1);
+    SkMessageBus<TestMessage>::Post(m2);
+
+    // Make sure we got two.
+    SkTDArray<TestMessage> messages;
+    inbox1.poll(&messages);
+    REPORTER_ASSERT(r, 2 == messages.count());
+    REPORTER_ASSERT(r, 5 == messages[0].x);
+    REPORTER_ASSERT(r, 6 == messages[1].x);
+
+    // Send another; check we get just that one.
+    const TestMessage m3 = { 1, 0.3f };
+    SkMessageBus<TestMessage>::Post(m3);
+    inbox1.poll(&messages);
+    REPORTER_ASSERT(r, 1 == messages.count());
+    REPORTER_ASSERT(r, 1 == messages[0].x);
+
+    // Nothing was sent since the last read.
+    inbox1.poll(&messages);
+    REPORTER_ASSERT(r, 0 == messages.count());
+
+    // Over all this time, inbox2 should have piled up 3 messages.
+    inbox2.poll(&messages);
+    REPORTER_ASSERT(r, 3 == messages.count());
+    REPORTER_ASSERT(r, 5 == messages[0].x);
+    REPORTER_ASSERT(r, 6 == messages[1].x);
+    REPORTER_ASSERT(r, 1 == messages[2].x);
+}
+
+// Multithreaded tests tbd.