1 files changed, 107 insertions, 0 deletions
diff --git a/metrics_library_test.cc b/metrics_library_test.cc
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+++ b/metrics_library_test.cc
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+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+
+#include <base/files/file_util.h>
+#include <base/files/scoped_temp_dir.h>
+#include <gmock/gmock.h>
+#include <gtest/gtest.h>
+
+#include "metrics/c_metrics_library.h"
+#include "metrics/metrics_library.h"
+
+
+class MetricsLibraryTest : public testing::Test {
+ protected:
+  virtual void SetUp() {
+    ASSERT_TRUE(temp_dir_.CreateUniqueTempDir());
+    lib_.InitForTest(temp_dir_.path());
+    // Defeat metrics enabled caching between tests.
+    lib_.cached_enabled_time_ = 0;
+  }
+
+  void SetMetricsConsent(bool enabled) {
+    if (enabled) {
+      ASSERT_EQ(base::WriteFile(lib_.consent_file_, "", 0), 0);
+    } else {
+      ASSERT_TRUE(base::DeleteFile(lib_.consent_file_, false));
+    }
+  }
+
+  void VerifyEnabledCacheHit(bool to_value);
+  void VerifyEnabledCacheEviction(bool to_value);
+
+  MetricsLibrary lib_;
+  base::ScopedTempDir temp_dir_;
+};
+
+TEST_F(MetricsLibraryTest, AreMetricsEnabledFalse) {
+  SetMetricsConsent(false);
+  EXPECT_FALSE(lib_.AreMetricsEnabled());
+}
+
+TEST_F(MetricsLibraryTest, AreMetricsEnabledTrue) {
+  SetMetricsConsent(true);
+  EXPECT_TRUE(lib_.AreMetricsEnabled());
+}
+
+void MetricsLibraryTest::VerifyEnabledCacheHit(bool to_value) {
+  // We might step from one second to the next one time, but not 100
+  // times in a row.
+  for (int i = 0; i < 100; ++i) {
+    lib_.cached_enabled_time_ = 0;
+    SetMetricsConsent(to_value);
+    lib_.AreMetricsEnabled();
+    // If we check the metrics status twice in a row, we use the cached value
+    // the second time.
+    SetMetricsConsent(!to_value);
+    if (lib_.AreMetricsEnabled() == to_value)
+      return;
+  }
+  ADD_FAILURE() << "Did not see evidence of caching";
+}
+
+void MetricsLibraryTest::VerifyEnabledCacheEviction(bool to_value) {
+  lib_.cached_enabled_time_ = 0;
+  SetMetricsConsent(!to_value);
+  ASSERT_EQ(!to_value, lib_.AreMetricsEnabled());
+
+  SetMetricsConsent(to_value);
+  // Sleep one second (or cheat to be faster) and check that we are not using
+  // the cached value.
+  --lib_.cached_enabled_time_;
+  ASSERT_EQ(to_value, lib_.AreMetricsEnabled());
+}
+
+TEST_F(MetricsLibraryTest, AreMetricsEnabledCaching) {
+  VerifyEnabledCacheHit(false);
+  VerifyEnabledCacheHit(true);
+  VerifyEnabledCacheEviction(false);
+  VerifyEnabledCacheEviction(true);
+}
+
+TEST_F(MetricsLibraryTest, AreMetricsEnabledNoCaching) {
+  // disable caching.
+  lib_.use_caching_ = false;
+
+  // Checking the consent repeatedly should return the right result.
+  for (int i=0; i<100; ++i) {
+    SetMetricsConsent(true);
+    ASSERT_EQ(true, lib_.AreMetricsEnabled());
+    SetMetricsConsent(false);
+    ASSERT_EQ(false, lib_.AreMetricsEnabled());
+  }
+}