crosshair-tool 0.0.102

Description

CrossHair is an analysis tool for Python that blurs the line between testing and
type systems.

If you have a function with type annotations and add a contract in a supported
syntax, CrossHair will attempt to find counterexamples for you.

CrossHair works by repeatedly calling your functions with symbolic inputs. It
uses an SMT solver (a kind of theorem prover) to explore viable execution paths
and find counterexamples for you. This is not a new idea; a Python approach was
first described in this paper. However, to my knowledge, CrossHair is the most
complete implementation: it can use symbolic reasoning for the built-in types,
user-defined classes, and much of the standard library.