SciFe: Scala framework for efficient enumeration of data structures with invariants

We introduce SciFe, a tool for automated generation of complex structures, suitable for tasks such as automated testing and synthesis. SciFe is capable of exhaustive, memoized enumeration of values from finite or infinite domains. SciFe is based on the concept of an enumerator, defined as an efficiently computable bijection between natural numbers and values from a given set. SciFe introduces higher-order enumerators which define enumerators that depend on additional parameters. SciFe also includes combinators that can construct more complex enumerators from existing ones while preserving exhaustiveness and efficiency. SciFe is a Scala library that implements a domain-specific language. This tool demo presents an overview of SciFe as well as its use to generate complex structures such as search trees and models of class hierarchies. Our experiments demonstrate better performance and shorter specifications when compared to existing approaches.