Editing Design by contract (section)

==Relationship to software testing==
Design by contract does not replace regular testing strategies, such as [[unit testing]], [[integration testing]] and [[system testing]]. Rather, it complements external testing with internal self-tests that can be activated both for isolated tests and in production code during a test-phase.

The advantage of internal self-tests is that they can detect errors before they manifest themselves as invalid results observed by the client. This leads to earlier and more specific error detection.

The use of assertions can be considered to be a form of [[test oracle]], a way of testing the design by contract implementation.