Laravel 7 error in PHPUnit postJson?

Question

PHPUnit

I am writing an API on Laravel 7.
The documentation has a postJson method, but when starting tests, it gives an error:

Call to undefined method Tests\Unit\NoteTest::postJson()

Answer 1

This is in feature tests, but not in unit tests. They are in different namespaces, although they are called the same.
Although nothing prevents changing to, except that this will slightly violate the logic of placing tests.
use PHPUnit\Framework\TestCase;
use Tests\TestCase;