PRT - Path-oriented Random Testing 

PRT  is a small SICStus Prolog program that performs uniform random testing at the level of path within a program under test. The tool takes as inputs a path condition, 
i.e. a set of constraints holding over input variables, and returns a sequence of test data that is uniformly distributed over the input space of the program under test.
Path condition can be provided under the form of clpfd constraints, using the syntax of the clpfd library, but it can also be provided by external tools.

An important parameter is the so-called division parameter k, which permits to tune PRT to distinct resolution techniques. When k=1, constraint refutation
is not used to build a Uniform Random Test data Generator while when k>1, constraint refutation is applied on 2^k subdomains of the input space to prune the
search space. In practice, small values of k have to be privileged in order to avoid combinatorial explosion. 

The source code of PRT can be downloaded here
It contains numerous examples and some explanations on usage. 

Two main predicates are available, namely   rt/5 and  prt/4  with the following parameters:
- C a path condition (given in clpfd constraints syntax)
- VARS a list of input variables
- N the requested length of Seq 
- K the division parameter

Both predicates return a sequence Seq of N test data that respect C.

rt/5 implements "pure" random testing without using path condition to minimize the number of rejects while
prt/4 implements Path-oriented Random Tesing.
Examples:
?- rt(domain([X,Y],0,100), (Y #> X + 50, X*Y #< 60), [X,Y], 1000, Seq1).

?- prt((domain([X,Y],0,100), Y #> X + 50, X*Y #< 60), [X,Y], 1000, 2, Seq3).

Benchmarks can be reproduced using the bench/2 predicate  (See Experiments section in the code)