1 files changed, 45 insertions, 0 deletions
diff --git a/dom/media/gtest/TestRTCStatsTimestampMaker.cpp b/dom/media/gtest/TestRTCStatsTimestampMaker.cpp
new file mode 100644
index 0000000000..931d5e107d
--- /dev/null
+++ b/dom/media/gtest/TestRTCStatsTimestampMaker.cpp
@@ -0,0 +1,45 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include <cmath>
+
+#include "gtest/gtest.h"
+#include "libwebrtcglue/SystemTime.h"
+
+using namespace mozilla;
+using namespace dom;
+
+TEST(RTCStatsTimestampMakerRealtimeClock, ConvertTimestampToNtpTime)
+{
+  RTCStatsTimestampMaker maker;
+  RTCStatsTimestampMakerRealtimeClock clock(maker);
+  constexpr auto ntpTo1Jan1970Ms = webrtc::kNtpJan1970 * 1000LL;
+  for (int i = 1000; i < 20000; i += 93) {
+    const auto t = webrtc::Timestamp::Micros(i);
+    const auto ntp = clock.ConvertTimestampToNtpTime(t);
+    // Because of precision differences, these round to a specific millisecond
+    // slightly differently.
+    EXPECT_NEAR(ntp.ToMs() - ntpTo1Jan1970Ms,
+                maker.ConvertRealtimeTo1Jan1970(t).ms(), 1.0)
+        << " for i=" << i;
+  }
+}
+
+TEST(RTCStatsTimestampMaker, ConvertNtpToDomTime)
+{
+  RTCStatsTimestampMaker maker;
+  RTCStatsTimestampMakerRealtimeClock clock(maker);
+  for (int i = 1000; i < 20000; i += 93) {
+    const auto t = webrtc::Timestamp::Micros(i);
+    const auto ntp = clock.ConvertTimestampToNtpTime(t);
+    const auto dom =
+        maker.ConvertNtpToDomTime(webrtc::Timestamp::Millis(ntp.ToMs()));
+    // Because of precision differences, these round to a specific millisecond
+    // slightly differently.
+    EXPECT_NEAR(std::lround(dom), std::lround(maker.ReduceRealtimePrecision(t)),
+                1.0)
+        << " for i=" << i;
+  }
+}