Quoting:
"Property-based testing (PBT) relies on properties which can be written in pseudocode as:
for all (x, y, ...)
such as precondition(x, y, ...) holds
property(x, y, ...) is true
Introductory examples usually illustrate the technique with testing a data structure or a function, by recording its inputs and outputs and checking that specified properties are all valid.
Few commonly known examples deal with stateful PBT applied to testing actual live systems. In his talk, Kowal gives such an example. The process involves the identification of properties, building a stateful model of the system under test (SUT), using that model to generate interesting test sequences, running the test sequences on the actual system, comparing at each step of the run the system behaviour and outputs to those predicted by the model, and shrinking failing test sequences to a minimal expression."
