An analysis tool for Python that blurs the line between testing and type systems.
THE LATEST NEWS: Python's most popular property-based testing tool, Hypothesis, now supports running CrossHair as an optional backend!
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.
Try CrossHair right now, in your browser, at crosshair-web.org!
CrossHair has IDE integrations for VS Code, PyCharm, and more.
Finally, CrossHair can do more than check contracts. It can also generate unit tests and find behavioral differences between functions.
Want to help? Sign up for email or RSS updates. Star ⭐️ the repository. There are other ways to help too.
FAQs
Analyze Python code for correctness using symbolic execution.
We found that crosshair-tool demonstrated a healthy version release cadence and project activity because the last version was released less than a year ago. It has 1 open source maintainer collaborating on the project.
Did you know?
Socket for GitHub automatically highlights issues in each pull request and monitors the health of all your open source dependencies. Discover the contents of your packages and block harmful activity before you install or update your dependencies.
Research
Security News
Malicious Go packages are impersonating popular libraries to install hidden loader malware on Linux and macOS, targeting developers with obfuscated payloads.
Security News
Bybit's $1.46B hack by North Korea's Lazarus Group pushes 2025 crypto losses to $1.6B in just two months, already surpassing all of 2024's $1.49B total.
Security News
OpenSSF has published OSPS Baseline, an initiative designed to establish a minimum set of security-related best practices for open source software projects.
