= Test Instance Post-processing

`{TestInstancePostProcessor}` defines the API for `Extensions` that wish to _post
process_ test instances.

Common use cases include injecting dependencies into the test instance, invoking custom
initialization methods on the test instance, etc.

For a concrete example, consult the source code for the `{MockitoExtension}` and the
`{SpringExtension}`.

[NOTE]
.Accessing the test-scoped `ExtensionContext`
====
You may override the `getTestInstantiationExtensionContextScope(...)` method to return
`TEST_METHOD` to make test-specific data available to your extension implementation or if
you want to xref:extensions/keeping-state-in-extensions.adoc[keep state] on the test method level.
====
