Subdomain (Partition) Testing

In subdomain testing, the input space of the program being tested is divided using a criterion of ‘sameness,’ grouping input points such that it seems unnecessary to try many in the same group. These subdomains are then sampled: it is required that each be covered by at least one test. There are a number of pitfalls in this procedure because the points in a subdomain are never truly ‘the same’; nevertheless, the method is the only imaginable way to systematize testing. Key terms: test coverage, functional testing, structural testing, input partition, sampling, subdomain homogeneity