`cy.then() timed out after waiting 4000ms. Your callback function returned a promise that never resolved.` on some tests using `axe-core` 4.7.1.

I'm trying to upgrade axe-core to version 4.7.1 but I'm finding that some of my Cypress a11y tests are now unexpectedly failing with this error:

cy.then() timed out after waiting 4000ms.

Your callback function returned a promise that never resolved.

The callback function was:

function (win) {
        if (isEmptyObjectorNull(context)) {
            context = undefined;
        }
        if (isEmptyObjectorNull(options)) {
            options = undefined;
        }
        if (isEmptyObjectorNull(violationCallback)) {
            violationCallback = undefined;
        }
        var _a = options || {}, includedImpacts = _a.includedImpacts, interval = _a.interval, retries = _a.retries, axeOptions = __rest(_a, ["includedImpacts", "interval", "retries"]);
        var remainingRetries = retries || 0;
        function runAxeCheck() {
            return win.axe
                .run(context || win.document, axeOptions)
                .then(function (_a) {
                var violations = _a.violations;
                var results = summarizeResults(includedImpacts, violations);
                if (results.length > 0 && remainingRetries > 0) {
                    remainingRetries--;
                    return new Promise(function (resolve) {
                        setTimeout(resolve, interval || 1000);
                    }).then(runAxeCheck);
                }
                else {
                    return results;
                }
            });
        }
        return runAxeCheck();
    }

It seems that the checks that axe-core is doing now takes longer than 4 seconds which causes then to timeout.

It looks like a workaround is to change the value of Cypress' defaultCommandTimeout but having to change this suite-wide or on a case-by-case basis for impacted tests is not a practical solution.

Another option could be to use the timeout option for uses of then in checkA11y but hardcoding it probably isn't a great idea and how long the timeout should be would also be unclear. 🤔

Start in src/index.ts at the checkA11y call around line 67 and reproduce the timeout with axe-core 4.7.1. Compare the behavior with Cypress's defaultCommandTimeout and the timeout option for then; done means affected accessibility checks complete without suite-wide or per-test timeout changes, with regression coverage.