browser/modules/test/head.js

   1 Cu.import("resource://gre/modules/Promise.jsm");
   2
   3 const SINGLE_TRY_TIMEOUT = 100;
   4 const NUMBER_OF_TRIES = 30;
   5
   6 function waitForConditionPromise(condition, timeoutMsg, tryCount=NUMBER_OF_TRIES) {
   7   let defer = Promise.defer();
   8   let tries = 0;
   9   function checkCondition() {
  10     if (tries >= tryCount) {
  11       defer.reject(timeoutMsg);
  12     }
  13     var conditionPassed;
  14     try {
  15       conditionPassed = condition();
  16     } catch (e) {
  17       return defer.reject(e);
  18     }
  19     if (conditionPassed) {
  20       return defer.resolve();
  21     }
  22     tries++;
  23     setTimeout(checkCondition, SINGLE_TRY_TIMEOUT);
  24   }
  25   setTimeout(checkCondition, SINGLE_TRY_TIMEOUT);
  26   return defer.promise;
  27 }
  28
  29 function waitForCondition(condition, nextTest, errorMsg) {
  30   waitForConditionPromise(condition, errorMsg).then(nextTest, (reason) => {
  31     ok(false, reason + (reason.stack ? "\n" + e.stack : ""));
  32   });
  33 }