Screen Assertion

A screen assertion enables you to monitor global changes to a particular screen throughout the evolution of your application. Waldo creates a screen assertion automatically for each screen in your test.


By default, Waldo sets the similarity ratio for a screen assertion to 70%. You always have the option to adjust or delete the assertion.

To adjust the similarity ratio for a screen assertion, simply move the thumb indicator on the slider to the desired value.



It's not about pixel

The similarity assertion ensures that the expected and actual state are structurally similar. It uses a score based on the number of elements, their positions on the screen, and their attributes. It does not take into account how they look like pixel-wise.

Note: You can always inspect screen structures by hovering the similarity assertion (both in runs and tests modals). Comparing the actual and expected screens that way can usually explain why they look pixel-wise identical but have less than 100% similarity.


Note: Waldo does not count automatically-created screen assertions in the number displayed in the screen badge for each step of a test.