jantimon / inp-tests

Cypress Tests to verify INP assumptions

This is a simple project to test the impact of different actions on the Input to Next paint metric.

Fast INPs

• non interactive elements have a good INP 🏃‍♀️
• button without side effects has a good INP 🏃‍♀️
• button with artificial main thread delay inside requestIdleCallback has a good INP 🏃‍♀️
• button with artificial main thread delay inside 2 requestAnimationFrame has a good INP 🏃‍♀️
• fetching data has a good INP 🏃‍♀️

Slow INPs

• button with artificial main thread delay inside requestAnimationFrame has a bad INP 🐌
• button with artificial main thread delay inside setTimeout has a bad INP 🐌
• button with artificial main thread delay has a bad INP 🐌
• :active does not improve a bad INP 🐌

Full test suite