Mojo: Add some tests for ChannelEndpointId, etc.

mojo/edk/system/channel_endpoint_id_unittest.cc

+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "mojo/edk/system/channel_endpoint_id.h"
+
+#include <sstream>
+
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace mojo {
+namespace system {
+namespace {
+
+TEST(ChannelEndpointIdTest, Basic) {
+  ChannelEndpointId invalid;
+  ChannelEndpointId bootstrap(ChannelEndpointId::GetBootstrap());
+
+  EXPECT_EQ(invalid, invalid);
+  EXPECT_EQ(bootstrap, bootstrap);
+  EXPECT_FALSE(invalid == bootstrap);
+
+  EXPECT_FALSE(invalid != invalid);
+  EXPECT_FALSE(bootstrap != bootstrap);
+  EXPECT_NE(invalid, bootstrap);
+
+  EXPECT_FALSE(invalid < invalid);
+  EXPECT_LT(invalid, bootstrap);
+
+  EXPECT_FALSE(invalid.is_valid());
+  EXPECT_TRUE(bootstrap.is_valid());
+
+  // Test assignment.
+  ChannelEndpointId copy;
+  copy = bootstrap;
+  EXPECT_EQ(copy, bootstrap);
+  copy = invalid;
+  EXPECT_EQ(copy, invalid);
+}
+
+// Tests values of invalid and bootstrap IDs. (This tests implementation
+// details.)
+TEST(ChannelEndpointIdTest, Value) {
+  EXPECT_EQ(0u, ChannelEndpointId().value());
+  EXPECT_EQ(1u, ChannelEndpointId::GetBootstrap().value());
+}
+
+// Tests ostream output. (This tests implementation details.)
+TEST(ChannelEndpointIdTest, Ostream) {
+  {
+    std::ostringstream stream;
+    stream << ChannelEndpointId();
+    EXPECT_EQ("0", stream.str());
+  }
+  {
+    std::ostringstream stream;
+    stream << ChannelEndpointId::GetBootstrap();
+    EXPECT_EQ("1", stream.str());
+  }
+}
+
+TEST(LocalChannelEndpointIdGeneratorTest, Basic) {
+  LocalChannelEndpointIdGenerator gen;
+
+  ChannelEndpointId id1;
+  EXPECT_FALSE(id1.is_valid());  // Check sanity.
+
+  id1 = gen.GetNext();
+  EXPECT_TRUE(id1.is_valid());
+
+  EXPECT_EQ(id1, ChannelEndpointId::GetBootstrap());
+
+  ChannelEndpointId id2 = gen.GetNext();
+  EXPECT_TRUE(id2.is_valid());
+  // Technically, nonequality here is an implementation detail, since, e.g.,
+  // random generation of IDs would be a valid implementation.
+  EXPECT_NE(id2, id1);
+  // ... but right now we just increment to generate IDs.
+  EXPECT_EQ(2u, id2.value());
+}
+
+}  // namespace
+
+// Tests that the generator handles wrap-around correctly. (This tests
+// implementation details.) This test isn't in an anonymous namespace, since
+// it needs to be friended.
+TEST(LocalChannelEndpointIdGeneratorTest, WrapAround) {
+  LocalChannelEndpointIdGenerator gen;
+  gen.next_channel_endpoint_id_.value_ = static_cast<uint32_t>(-1);
+
+  ChannelEndpointId id = gen.GetNext();
+  EXPECT_TRUE(id.is_valid());
+  EXPECT_EQ(static_cast<uint32_t>(-1), id.value());
+
+  id = gen.GetNext();
+  EXPECT_TRUE(id.is_valid());
+  EXPECT_EQ(1u, id.value());
+}
+
+}  // namespace system
+}  // namespace mojo