What data and objects are permissible to save and initialize using fixtures?

Fixtures are used to prepare test data and objects necessary for executing tests. Typically, fixtures contain:

• Static data required for the test (e.g., JSON objects, configurations, parameters).
• Model objects or entities with predefined values.
• Environment settings or states that should be consistent across multiple tests.

It is important that the data in fixtures is deterministic and reproducible to ensure test stability. It is not recommended to store dynamic data in fixtures that depend on external services or time, as this can lead to test instability.