Salesforce Developers PDI Question # 55 Topic 6 Discussion

Records created in the test setup method cannot be updated in individual test methods.

In a test setup method, test data is inserted once and made available for all test methods In the test class.

A method defined with the @testSetup annotation executes once for each test method in the test class and counts towards system limits.

The @testSetup annotation is not supported when the @isTest(SeeAllData=True) annotation is used .