Implementation details: impact on testability

Implementations in the safety environment have a requirement for a significantly more detailed and exhaustive testing than in the non-safety environment. If an API function has parameters with very broad ranges, then their impact on testability should be discussed. Similarly, if a function has parameters for which allowed and disallowed sets of values are hard to determine, there should be discussion in the API specification how tests such as fault injection should be handled with respect to the safety standards that require such tests. In addition to issues for implementers, the mentioned examples of parameters can cause issues to users as well, since coding guidelines, such as MISRA guidelines, usually have a rule requiring that validity of parameters passed to library functions be checked. This could lead to different implementers performing this validity check in different ways, resulting in different validation accuracy, yet all of them be given the same approval of conformance to the API specification.

Start by reading the issue body and comparing its safety-environment testing concerns with the non-safety environment. Determine how the API specification should address broad or ambiguous parameter ranges, fault-injection tests, and differing validity checks by implementers; done means the guideline gives actionable coverage for both implementers and users.