1 files changed, 35 insertions, 1 deletions
diff --git a/base/chrono_utils_test.cpp b/base/chrono_utils_test.cpp
index 057132d9f..da442f455 100644
--- a/base/chrono_utils_test.cpp
+++ b/base/chrono_utils_test.cpp
@@ -19,6 +19,9 @@
 #include <time.h>
 
 #include <chrono>
+#include <sstream>
+#include <string>
+#include <thread>
 
 #include <gtest/gtest.h>
 
@@ -42,5 +45,36 @@ TEST(ChronoUtilsTest, BootClockNowSeconds) {
   EXPECT_EQ(now, boot_seconds);
 }
 
+template <typename T>
+void ExpectAboutEqual(T expected, T actual) {
+  auto expected_upper_bound = expected * 1.05f;
+  auto expected_lower_bound = expected * .95;
+  EXPECT_GT(expected_upper_bound, actual);
+  EXPECT_LT(expected_lower_bound, actual);
+}
+
+TEST(ChronoUtilsTest, TimerDurationIsSane) {
+  auto start = boot_clock::now();
+  Timer t;
+  std::this_thread::sleep_for(50ms);
+  auto stop = boot_clock::now();
+  auto stop_timer = t.duration();
+
+  auto expected = std::chrono::duration_cast<std::chrono::milliseconds>(stop - start);
+  ExpectAboutEqual(expected, stop_timer);
+}
+
+TEST(ChronoUtilsTest, TimerOstream) {
+  Timer t;
+  std::this_thread::sleep_for(50ms);
+  auto stop_timer = t.duration().count();
+  std::stringstream os;
+  os << t;
+  decltype(stop_timer) stop_timer_from_stream;
+  os >> stop_timer_from_stream;
+  EXPECT_NE(0, stop_timer);
+  ExpectAboutEqual(stop_timer, stop_timer_from_stream);
+}
+
 }  // namespace base
-}  // namespace android
-\ No newline at end of file
+}  // namespace android