Muting Noisy XHR Logs in Cypress

(This guide has been updated multiple times, especially since the release of Cypress 10)

For a while now, our Cypress runner has been quite noisy, generating lots of XHR requests in the log as our tests run. A bug was introduced into Cypress in the last few versions that has made it quite difficult to mute these. Fortunately, I found a solution that Simen Brekken helpfully posted here and I felt like I'd share it with the Dev audience in case it was helpful to someone else.

For the fix, we add a flag to our cypress.config.ts to allow us to enable or disable rich logging as needed.

e2e: {
  hideXHRInCommandLog: true
}

In our /cypress/support/e2e.ts file, we have:

// Hide fetch/XHR requests from command log
if (Cypress.config("hideXHRInCommandLog")) {
  const app = window.top;

  if (
    app &&
    !app.document.head.querySelector("[data-hide-command-log-request]")
  ) {
    const style = app.document.createElement("style");
    style.innerHTML =
      ".command-name-request, .command-name-xhr { display: none }";
    style.setAttribute("data-hide-command-log-request", "");

    app.document.head.appendChild(style);
  }
}

And then lastly, in /support/cypress.d.ts, we add:

declare namespace Cypress {
  interface ResolvedConfigOptions {
    hideXHRInCommandLog?: boolean;
  }
}

This solution uses CSS to prevent the XHR requests from being picked up in the DOM and thereby reported to the Cypress runner. It's not the most elegant solution, but it'll work for now until we get a better fix from Cypress. Thanks, Simen!