Add metrics library tests. Some metrics daemon API cleanup.

src/platform/metrics/metrics_library_test.cc

Index: src/platform/metrics/metrics_library_test.cc
diff --git a/src/platform/metrics/metrics_library_test.cc b/src/platform/metrics/metrics_library_test.cc
new file mode 100644
index 0000000000000000000000000000000000000000..f585d350734b10c13e49dd2818059d9d54bf6051
--- /dev/null
+++ b/src/platform/metrics/metrics_library_test.cc
@@ -0,0 +1,89 @@
+// Copyright (c) 2010 The Chromium OS 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 "metrics_library.h"
+
+#include <cstring>
+
+#include <base/file_util.h>
+#include <gtest/gtest.h>
+
+static const FilePath kTestUMAEventsFile("test-uma-events");
+
+class MetricsLibraryTest : public testing::Test {
+ protected:
+  virtual void SetUp() {
+    EXPECT_EQ(NULL, lib_.uma_events_file_);
+    lib_.Init();
+    EXPECT_TRUE(NULL != lib_.uma_events_file_);
+    lib_.uma_events_file_ = kTestUMAEventsFile.value().c_str();
+  }
+
+  virtual void TearDown() {
+    file_util::Delete(kTestUMAEventsFile, false);
+  }
+
+  MetricsLibrary lib_;
+};
+
+TEST_F(MetricsLibraryTest, FormatChromeMessage) {
+  char buf[7];
+  const int kLen = 6;
+  EXPECT_EQ(kLen, lib_.FormatChromeMessage(7, buf, "%d", 1));
+
+  char exp[kLen];
+  sprintf(exp, "%c%c%c%c1", kLen, 0, 0, 0);
+  EXPECT_EQ(0, memcmp(exp, buf, kLen));
+}
+
+TEST_F(MetricsLibraryTest, FormatChromeMessageTooLong) {
+  char buf[7];
+  EXPECT_EQ(-1, lib_.FormatChromeMessage(7, buf, "test"));
+}
+
+TEST_F(MetricsLibraryTest, SendEnumToUMA) {
+  char buf[100];
+  const int kLen = 40;
+  EXPECT_TRUE(lib_.SendEnumToUMA("Test.EnumMetric", 1, 3));
+  EXPECT_EQ(kLen, file_util::ReadFile(kTestUMAEventsFile, buf, 100));
+
+  char exp[kLen];
+  sprintf(exp, "%c%c%c%clinearhistogram%cTest.EnumMetric 1 3",
+          kLen, 0, 0, 0, 0);
+  EXPECT_EQ(0, memcmp(exp, buf, kLen));
+}
+
+TEST_F(MetricsLibraryTest, SendMessageToChrome) {
+  EXPECT_TRUE(lib_.SendMessageToChrome(4, "test"));
+  EXPECT_TRUE(lib_.SendMessageToChrome(7, "content"));
+  std::string uma_events;
+  EXPECT_TRUE(file_util::ReadFileToString(kTestUMAEventsFile, &uma_events));
+  EXPECT_EQ("testcontent", uma_events);
+}
+
+TEST_F(MetricsLibraryTest, SendMessageToChromeUMAEventsBadFileLocation) {
+  // Checks that the library doesn't die badly if the file can't be
+  // created.
+  static const char kDoesNotExistFile[] = "/does/not/exist";
+  lib_.uma_events_file_ = kDoesNotExistFile;
+  static const char kDummyMessage[] = "Dummy Message";
+  EXPECT_FALSE(lib_.SendMessageToChrome(strlen(kDummyMessage), kDummyMessage));
+  file_util::Delete(FilePath(kDoesNotExistFile), false);
+}
+
+TEST_F(MetricsLibraryTest, SendToUMA) {
+  char buf[100];
+  const int kLen = 37;
+  EXPECT_TRUE(lib_.SendToUMA("Test.Metric", 2, 1, 100, 50));
+  EXPECT_EQ(kLen, file_util::ReadFile(kTestUMAEventsFile, buf, 100));
+
+  char exp[kLen];
+  sprintf(exp, "%c%c%c%chistogram%cTest.Metric 2 1 100 50", kLen, 0, 0, 0, 0);
+  EXPECT_EQ(0, memcmp(exp, buf, kLen));
+}
+
+int main(int argc, char** argv) {
+  testing::InitGoogleTest(&argc, argv);
+  return RUN_ALL_TESTS();
+}