As your project grows, and the number of scriptsA piece of code that allows you to create your own Components, trigger game events, modify Component properties over time and respond to user input in any way you like. More info
See in Glossary, classes and methods in your project increases, it can become difficult to ensure that a change in one part of your code doesn’t break things somewhere else.
Automated testing helps you check that all parts of your code are functioning as expected. It saves time by identifying where and when problems occur as soon as they are introduced during development, rather than relying on manual testing, or even worse - bug reports from your end users.
The Unity Test Framework package (formerly the “Unity Test Runner”) is a tool that allows you to test your code in both Edit mode and Play mode, and also on target platforms such as Standalone, Android, or iOS.
For more information on other versions of the Test Framework package, see the com.unity.test-framework page.