Provide documentation on how to use correctly browser.wait with protractor.ExpectedConditions

[evilaliv3]

I'm trying to use the protractor.ExpectedConditions together with browser.wait() but i'm sporadically failing with the error: stale element reference: element is not attached to the page document.

The way i'm using the function is the following:

function (locator, timeout) {
  var t = timeout === undefined ? exports.browserTimeout() : timeout;
  var EC = protractor.ExpectedConditions;
  browser.wait(EC.invisibilityOf(element(locator)), t);
};

the reason that is causing the failure is probably that between the call to element(locator) and the usage of the element i've applications refresh that remove the element and cause the issue when the refernece is used.

i've not found any good documentation to use this routines without having this issue.

could you please provide some guidelines?

[evilaliv3]

@juliemr it seems to me that this is related to #2277

is it possible that there is a regression?

[evilaliv3]

Solved using element.isVisible in place of the ExpectedCondition:

function (locator, timeout) {
  var t = timeout === undefined ? exports.browserTimeout() : timeout;
  return browser.wait(function() {
    return element(locator).isDisplayed().then(function(present) {
      return present;
    });
  }, t);
};

i would suggest @cnishina that also for EC.invisibilityOf you adopt the same returning false in place of raising an exception.

[evilaliv3]

No damn, i'm still getting the error in a sporadic way even using the isDisplayed().

i confirm so that we are facing a regression on #2277

[tilmanschweitzer]

@evilaliv3 Hi, this issue is caused by a race condition between the isPresent and isDisplayed check. If the element is removed between both calls or while isDisplayed is executed you get a NoSuchElementError or a StaleElementReferenceError.

This problem is solved for visibilityOf (https://github.com/angular/protractor/pull/3958/files), but it still exists for textToBePresentInElement and probably others.

Before these changes are release in a future version your can monkey patch your ExpectedContions and use workaround functions that I put in an npm module

https://www.npmjs.com/package/protractor-save-expected-conditions