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<!DOCTYPE html>
<meta charset=utf-8>
<title>Test for promise resolution ordering with thenables and promises</title>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<div id="log"></div>
<script>
/* global async_test, assert_true, assert_equals */

var t = async_test("A promise resolved first (with a thenable) should trigger its callbacks before a promise resolved second (with a promise).");
t.step(function() {
  var customThenCalled = false;
  var p0 = Promise.resolve();
  p0.then = function(resolved, rejected) {
    customThenCalled = true;
    Promise.prototype.then.call(this, resolved, rejected);
  };
  var p1 = new Promise(function(r) { r(p0); });
  delete p0.then;
  var p2 = new Promise(function(r) { r(p0); });
  var resolutionOrder = "";
  Promise.all([ p1.then(function() { resolutionOrder += "1"; }),
                p2.then(function() { resolutionOrder += "2"; }) ])
         .then(t.step_func_done(function() {
           assert_true(customThenCalled, "Should have called custom then");
           assert_equals(resolutionOrder, "12");
         }));
});
</script>