1 files changed, 13 insertions, 0 deletions
diff --git a/testing/web-platform/tests/hr-time/monotonic-clock.any.js b/testing/web-platform/tests/hr-time/monotonic-clock.any.js
new file mode 100644
index 0000000000..c53b04d844
--- /dev/null
+++ b/testing/web-platform/tests/hr-time/monotonic-clock.any.js
@@ -0,0 +1,13 @@
+// The time values returned when calling the now method MUST be monotonically increasing and not subject to system clock adjustments or system clock skew.
+test(function() {
+  assert_true(self.performance.now() > 0, "self.performance.now() returns positive numbers");
+}, "self.performance.now() returns a positive number");
+
+// The difference between any two chronologically recorded time values returned from the now method MUST never be negative.
+test(function() {
+    var now1 = self.performance.now();
+    var now2 = self.performance.now();
+    assert_true((now2-now1) >= 0, "self.performance.now() difference is not negative");
+  },
+  "self.performance.now() difference is not negative"
+);