Generating Unit Tests with Structured System Interactions

There is a large body of work in the literature about
automatic unit tests generation, and many successful results have
been reported so far. However, current approaches target library
classes, but not full applications.
A major obstacle for testing full applications is that they
interact with the environment. For example, they establish connections
to remote servers. Thoroughly testing such applications
requires tests that completely control the interactions between
the application and its environment.
Recent techniques based on mocking enable the generation of
tests which include environment interactions; however, generating
the right type of interactions is still an open problem.
In this paper, we describe a novel approach which addresses
this problem by enhancing search-based testing with complex test
data generation. Experiments on an artificial system show that
the proposed approach can generate effective unit tests. Compared
with current techniques based on mocking, we generate
more robust unit tests which achieve higher coverage and are,
arguably, easier to read and understand.