shinytest

shinytest provides automated testing for Shiny applications through a simulation-based approach that you can control programmatically. It enables you to script interactions with your app and verify behavior remains consistent across changes.

The package uses snapshot-based testing where initial test runs capture application state, and subsequent runs compare against those snapshots to detect regressions. However, shinytest is deprecated and relies on PhantomJS, which is no longer maintained, so it may not work with Shiny versions after 1.8.1. Users should migrate to shinytest2, which uses modern Chromium-based browsers.