Cypress test hangs forever when system throws an unexpected alert during the test #27896

tausif29 · 2023-09-25T09:00:42Z

Current behavior

When Web application unexpectedly throws an error by alert box
Cypress test hangs/stuck forever and test never gets completed or failed until user manually closes the browser.

I have a below sample HTML page to reproduce the issue, Here I am explicitly throwing the alert box after 5 seconds of the page load.

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Button Alert Example</title>
</head>
<body>

  <button onclick="changeLabel()">Click me for a label</button>
  <p id="label"></p>

  <iframe id="myFrame" style="display:none;"></iframe>

  <script>
    // Show alert after 5 seconds of page load within the frame
    setTimeout(function() {
      var frame = document.getElementById('myFrame');
      frame.style.display = 'block';
      frame.contentWindow.alert("Error While Processing Request");
    }, 5000);

    function changeLabel() {
      document.getElementById('label').innerText = "You clicked the button!";
    }
  </script>

</body>
</html>

Below is the Cypress test to reproduce the issue:

describe('Reproduce Alert Test', () => {
  it('Handle alert in a Frame', () => {
    cy.visit('/alert-test.html');
    cy.wait(6000)

    // Verify page title
    cy.title().should('eq', 'Alert Example');

    // Click the button and verify the label
    cy.get('button').contains('Click me for a label').click();
    cy.get('#label').should('have.text', 'You clicked the button!');
  });
});

NOTE: Issue gets reproduced when the webpage contains the the iFrame, Without iFrame Cypress automatically accepts the alert message.

Desired behavior

Either Cypress test should automatically accept the alert message and test should be continued further or Cypress test should gets failed immediately.

Test code to reproduce

Sample HTML Page to Reproduce the Issue:

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Button Alert Example</title>
</head>
<body>

  <button onclick="changeLabel()">Click me for a label</button>
  <p id="label"></p>

  <iframe id="myFrame" style="display:none;"></iframe>

  <script>
    // Show alert after 5 seconds of page load within the frame
    setTimeout(function() {
      var frame = document.getElementById('myFrame');
      frame.style.display = 'block';
      frame.contentWindow.alert("Error While Processing Request");
    }, 5000);

    function changeLabel() {
      document.getElementById('label').innerText = "You clicked the button!";
    }
  </script>

</body>
</html>

Sample Cypress Code:

describe('Reproduce Alert Test', () => {
  it('Handle alert in a Frame', () => {
    cy.visit('/alert-test.html');
    cy.wait(6000)

    // Verify page title
    cy.title().should('eq', 'Alert Example');

    // Click the button and verify the label
    cy.get('button').contains('Click me for a label').click();
    cy.get('#label').should('have.text', 'You clicked the button!');
  });
});

Cypress Version

All

Node version

All

Operating System

All

Debug Logs

No response

Other

No response

The text was updated successfully, but these errors were encountered:

nagash77 · 2023-09-25T17:59:19Z

@tausif29 can you please specify the version(s) of Cypress, Node and what OS(es) you are running and seeing this behavior? Please also include debug logs which will assist in helping us debug this issue. Are you using Test replay as well?

tausif29 · 2023-09-26T05:37:26Z

@nagash77 Issue is not version specific, It replicates on the all the versions, I have checked on version 10 , 12 & 13

I have shared the sample HTML & Cypress Code to reproduce the issue.

kmieshkov1 · 2023-10-07T18:44:22Z

Have the same issue. I was trying to handle that with cypress events like cy.on('window:alert', () => true) but it doesn't work either

ojemuyiwa · 2023-10-10T12:15:43Z

Just a thought @tausif29 in your e2e.ts or index.js in support do you have:

Cypress.on('uncaught:exception', (err, runnable) => {
    return false;
});

tausif29 · 2023-10-11T06:58:49Z

Just a thought @tausif29 in your e2e.ts or index.js in support do you have:
Cypress.on('uncaught:exception', (err, runnable) => {
    return false;
});

@ojemuyiwa Yes its there in my test [Refer below screenshot]

ojemuyiwa · 2023-10-11T16:05:54Z

Just a thought @tausif29 in your e2e.ts or index.js in support do you have:
Cypress.on('uncaught:exception', (err, runnable) => {
    return false;
});
@ojemuyiwa Yes its there in my test [Refer below screenshot]

Ahh I see, so although I don't see any use case for an iframe showing alerts, your cy.on('window:alert' targets the parent window and not the iframe window. if you get the iframe using cy.get('#myFrame') you may access its window. See examples on the same window https://testersdock.com/cypress-javascript-alert-confirm-prompt/

kmieshkov1 · 2023-10-30T14:34:48Z

@ojemuyiwa The issue is: if an alert pops up from the main content (top) Cypress handles it correctly and accepts it by default, but when alerts are invoked from the iframe - Cypress hangs, cy.on('window:alert', () => true) doesn't work in this case
The expected behavior is to handle alerts disregarding from where they were invoked since it's blocking the whole application (by the nature of alert windows)

hatseh · 2023-11-11T19:10:43Z

We are facing the same issue. I confirm what @tausif29 said, we can reproduce it on all versions of node/cypress using the code sample they provided.

kmieshkov1 · 2024-03-14T22:31:22Z

Hey @jennifer-shehane 👋 any updates on this one?

samelawrence · 2024-03-22T14:20:48Z

+1 for this thread, we are experiencing the same issue and it is disrupting major portions of our test suite. I wonder if this is related to the Chrome team deprecating the unload event? I can only reproduce this issue reliably in Chrome.

jennifer-shehane · 2024-04-01T17:05:33Z

I'm able to recreate this given the example in Chrome, Firefox, and Electron in Cypress 13.7.1. This doesn't seem browser specific, or related to Chrome's deprecation of the upload event.

We don't have a timeline to share for addressing this issue unfortunately.

samelawrence · 2024-04-01T17:35:05Z

@jennifer-shehane Thanks for looking into this! I'll stay subscribed to this issue and hope for an update soon, as this is currently blocking large portions of our test suite. If possible, it would be really helpful to know what version introduced this bug. When I rolled my Cypress installation back to a version when we last had successful runs (13.6.4), I was still able to reproduce the bug, so I haven't been able to pinpoint when this change was introduced. If anyone else seeing this can answer my question, please do - I know Jennifer has a lot on her plate. Thanks!

RTJakobs · 2024-05-28T11:44:00Z

Hello, I have been working with Cypress since the beginning of the year and have now also encountered the problem that I cannot automate a window that comes from an IFrame.
Is there already an update or a Cypress version that can solve the problem?

hatseh · 2024-05-28T13:11:50Z

One solution we found is to use the cy.stub() utility function: https://docs.cypress.io/api/commands/stub.
This way we stub window.alert, window.confirm, window.prompt or window.print

const stubWindow = (win) => {
  if (win.alert.restore) {
    win.alert.restore()
  }
  cy.stub(win, 'alert')
    .callsFake(() => {
      throw new Error('window.alert() called, failing current test!')
    })
    .as('alert')
}

RTJakobs · 2024-05-28T13:52:25Z

Would I put this source code e.g. in beforeEach() or does it have to be directly in the test case?
And when I have clicked on my element, do I then use the const together with cy.on()?

hatseh · 2024-05-29T13:32:39Z

We call it inside a getIframe function that is used to get the body of an iframe to fetch any element inside that iframe.

Cypress.Commands.add('getIframe', (iframeSelector = 'iframe', selector = 'body') => {
  cy.get(iframeSelector)
    .its('0.contentDocument')
    .then((doc) => {
      const win = doc.defaultView
      stubWindow(win)
      return cy.wrap(win.document.body, { log: false })
    })
})

nagash77 self-assigned this Sep 25, 2023

jennifer-shehane unassigned nagash77 Jan 24, 2024

jennifer-shehane added type: bug stage: needs investigating Someone from Cypress needs to look at this labels Apr 1, 2024

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Cypress test hangs forever when system throws an unexpected alert during the test #27896

Cypress test hangs forever when system throws an unexpected alert during the test #27896

tausif29 commented Sep 25, 2023 •

edited by jennifer-shehane

nagash77 commented Sep 25, 2023

tausif29 commented Sep 26, 2023

kmieshkov1 commented Oct 7, 2023

ojemuyiwa commented Oct 10, 2023

tausif29 commented Oct 11, 2023

ojemuyiwa commented Oct 11, 2023

kmieshkov1 commented Oct 30, 2023

hatseh commented Nov 11, 2023

kmieshkov1 commented Mar 14, 2024

samelawrence commented Mar 22, 2024 •

edited

jennifer-shehane commented Apr 1, 2024

samelawrence commented Apr 1, 2024

RTJakobs commented May 28, 2024

hatseh commented May 28, 2024

RTJakobs commented May 28, 2024

hatseh commented May 29, 2024

Cypress test hangs forever when system throws an unexpected alert during the test #27896

Cypress test hangs forever when system throws an unexpected alert during the test #27896

Comments

tausif29 commented Sep 25, 2023 • edited by jennifer-shehane

Current behavior

Desired behavior

Test code to reproduce

Cypress Version

Node version

Operating System

Debug Logs

Other

nagash77 commented Sep 25, 2023

tausif29 commented Sep 26, 2023

kmieshkov1 commented Oct 7, 2023

ojemuyiwa commented Oct 10, 2023

tausif29 commented Oct 11, 2023

ojemuyiwa commented Oct 11, 2023

kmieshkov1 commented Oct 30, 2023

hatseh commented Nov 11, 2023

kmieshkov1 commented Mar 14, 2024

samelawrence commented Mar 22, 2024 • edited

jennifer-shehane commented Apr 1, 2024

samelawrence commented Apr 1, 2024

RTJakobs commented May 28, 2024

hatseh commented May 28, 2024

RTJakobs commented May 28, 2024

hatseh commented May 29, 2024

tausif29 commented Sep 25, 2023 •

edited by jennifer-shehane

samelawrence commented Mar 22, 2024 •

edited