Add m-esr52 at 52.6.0

1 files changed, 76 insertions, 0 deletions

diff --git a/dom/performance/tests/test_worker_performance_now.js b/dom/performance/tests/test_worker_performance_now.js
new file mode 100644
index 000000000..c2a905031
--- /dev/null
+++ b/dom/performance/tests/test_worker_performance_now.js
@@ -0,0 +1,76 @@
+function ok(a, msg) {
+  dump("OK: " + !!a + "  =>  " + a + ": " + msg + "\n");
+  postMessage({type: 'status', status: !!a, msg: a + ": " + msg });
+}
+
+function workerTestDone() {
+  postMessage({ type: 'finish' });
+}
+
+function workerTestGetOSCPU(cb) {
+  addEventListener('message', function workerTestGetOSCPUCB(e) {
+    if (e.data.type !== 'returnOSCPU') {
+      return;
+    }
+    removeEventListener('message', workerTestGetOSCPUCB);
+    cb(e.data.result);
+  });
+  postMessage({
+    type: 'getOSCPU'
+  });
+}
+
+ok(self.performance, "Performance object should exist.");
+ok(typeof self.performance.now == 'function', "Performance object should have a 'now' method.");
+var n = self.performance.now(), d = Date.now();
+ok(n >= 0, "The value of now() should be equal to or greater than 0.");
+ok(self.performance.now() >= n, "The value of now() should monotonically increase.");
+
+// The spec says performance.now() should have micro-second resolution, but allows 1ms if the platform doesn't support it.
+// Our implementation does provide micro-second resolution, except for windows XP combined with some HW properties
+// where we can't use QueryPerformanceCounters (see comments at mozilla-central/xpcom/ds/TimeStamp_windows.cpp).
+// This XP-low-res case results in about 15ms resolutions, and can be identified when perf.now() returns only integers.
+//
+// Since setTimeout might return too early/late, our goal is that perf.now() changed within 2ms
+// (or 25ms for XP-low-res), rather than specific number of setTimeout(N) invocations.
+// See bug 749894 (intermittent failures of this test)
+var platformPossiblyLowRes;
+workerTestGetOSCPU(function(oscpu) {
+    platformPossiblyLowRes = oscpu.indexOf("Windows NT 5.1") == 0; // XP only
+    setTimeout(checkAfterTimeout, 1);
+});
+var allInts = (n % 1) == 0; // Indicator of limited HW resolution.
+var checks = 0;
+
+function checkAfterTimeout() {
+  checks++;
+  var d2 = Date.now();
+  var n2 = self.performance.now();
+
+  allInts = allInts && (n2 % 1) == 0;
+  var lowResCounter = platformPossiblyLowRes && allInts;
+
+  if ( n2 == n && checks < 50 && // 50 is just a failsafe. Our real goals are 2ms or 25ms.
+       ( (d2 - d) < 2 // The spec allows 1ms resolution. We allow up to measured 2ms to ellapse.
+         ||
+         lowResCounter &&
+         (d2 - d) < 25
+       )
+     ) {
+    setTimeout(checkAfterTimeout, 1);
+    return;
+  }
+
+  // Loose spec: 1ms resolution, or 15ms resolution for the XP-low-res case.
+  // We shouldn't test that dt is actually within 2/25ms since the iterations break if it isn't, and timeout could be late.
+  ok(n2 > n, "Loose - the value of now() should increase within 2ms (or 25ms if low-res counter) (delta now(): " + (n2 - n) + " ms).");
+
+  // Strict spec: if it's not the XP-low-res case, while the spec allows 1ms resolution, it prefers microseconds, which we provide.
+  // Since the fastest setTimeout return which I observed was ~500 microseconds, a microseconds counter should change in 1 iteretion.
+  ok(n2 > n && (lowResCounter || checks == 1),
+     "Strict - [if high-res counter] the value of now() should increase after one setTimeout (hi-res: " + (!lowResCounter) +
+                                                                                              ", iters: " + checks +
+                                                                                              ", dt: " + (d2 - d) +
+                                                                                              ", now(): " + n2 + ").");
+  workerTestDone();
+};