Experiments

If you'd like to try out what we're working on in the Test Runner, you can enable beta features for your project by turning on the experimental features you'd like to try.

Configuration

You can pass the configuration options below to enable or disable experiments. See our Configuration Guide on how to pass configuration to Cypress.

OptionDefaultDescription
experimentalFetchPolyfillfalseAutomatically replaces window.fetch with a polyfill that Cypress can spy on and stub. Note: experimentalFetchPolyfill has been deprecated in Cypress 6.0.0 and will be removed in a future release. Consider using cy.intercept() to intercept fetch requests instead.
experimentalInteractiveRunEventsfalseAllows listening to the before:run, after:run, before:spec, and after:spec events in the plugins file during interactive mode.
experimentalSessionSupportfalseEnable use of cy.session() and new behavior to handle caching and restoring cookies, localStorage, and sessionStorage.
experimentalSourceRewritingfalseEnables AST-based JS/HTML rewriting. This may fix issues caused by the existing regex-based JS/HTML replacement algorithm. See #5273 for details.
experimentalStudiofalseGenerate and save commands directly to your test suite by interacting with your app as an end user would. See Cypress Studio for more details.

History

VersionChanges
8.2.0Added support for experimentalSessionSupport.
7.1.0Added support for experimentalInteractiveRunEvents.
7.0.0Removed experimentalComponentTesting and made it the default behavior.
6.7.0Removed experimentalRunEvents and made it the default behavior.
6.3.0Added support for experimentalStudio.
6.2.0Added support for experimentalRunEvents.
6.0.0Removed experimentalNetworkStubbing and made it the default behavior when using cy.intercept().
6.0.0Deprecated experimentalFetchPolyfill.
5.2.0Removed experimentalShadowDomSupport and made it the default behavior.
5.1.0Added support for experimentalNetworkStubbing.
5.0.0Removed experimentalGetCookiesSameSite and made it the default behavior.
4.9.0Added support for experimentalFetchPolyfill.
4.8.0Added support for experimentalShadowDomSupport.
4.6.0Added support for experimentalSourceRewriting.
4.5.0Added support for experimentalComponentTesting.
4.3.0Added support for experimentalGetCookiesSameSite.