Which of the following are formal tests, and therefore must be documented?

Integration tests are indeed considered formal tests that must be documented, as they are essential for verifying that different components or systems interact correctly. During integration testing, you confirm that the integrated components function together as intended, ensuring that data flows seamlessly between systems. This is critical in an SAP S/4HANA implementation to maintain the integrity of business processes that span multiple systems or applications.

Documentation of integration tests provides a clear account of test scenarios, execution results, and any issues encountered, serving as valuable reference material for future testing phases and system audits. This formal approach helps to ensure compliance with quality assurance standards and facilitates smoother transitions to production.

While unit tests and business process tests also play vital roles in the testing phase, they have different focuses. Unit tests target individual components or modules, usually at the developer level, and may not always require extensive formal documentation. Business process tests, on the other hand, verify that specific business processes work correctly within the integrated system, but they also might not have the same level of formal documentation requirement as integration tests. String tests, often related to user interface flows or data integrity, are more situational and do not fit the category of formal tests requiring documentation.