998206 - Add "shuffle" option to run reftests in random order

Status: RESOLVED FIXED

(Core :: Layout, defect)

Comment 1

[Robert O'Callahan (:roc) (email my personal email if necessary)]

Attachment: fix

Comment 2

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

Comment on attachment 8408790 [details] [diff] [review]
fix

>+    try {
>+      gShuffle = prefs.getBoolPref("reftest.shuffle");
>+    } catch (e) {
>+      gShuffle = false;
>+    }

I'm not sure which prefs go in OnRefTestLoad and which prefs go in StartTests.  This seems more like the ones in StartTests.  (That bit is #ifdef BOOTSTRAP, though.)

>+function Shuffle(array)
>+{
>+    for (var i = array.length - 1; i > 0; i--) {
>+        var j = Math.floor(Math.random() * (i + 1));
>+        var temp = array[i];
>+        array[i] = array[j];
>+        array[j] = temp;
>+    }
>+}

Maybe link to http://en.wikipedia.org/wiki/Fisher%E2%80%93Yates_shuffle in a comment?  (It wasn't immediately obvious to me that the resulting positions in the array are uniformly distributed, although I think that was partly due to misreading the code the first time through.)

Comment 3

[Robert O'Callahan (:roc) (email my personal email if necessary)]

https://hg.mozilla.org/integration/mozilla-inbound/rev/a344959a5756

Comment 4

[Ryan VanderMeulen [:RyanVM]]

https://hg.mozilla.org/mozilla-central/rev/a344959a5756