Was looking at contributing to test coverage, and was following the guidelines for contributing in CONTRIBUTING.md. Found an issue with the file, in that it asks you to run npm run missing-tests to generate the missing tests. This doesn't work any more. Managed to track down how you generate missing tests (by running generate/index.js). This also runs some other generating code.

I'm happy to update the contributing.md file to mention that you need to run node generate/index.js, or update the package.json to have a generate command, and submit a pull request.

Let me know how to proceed, thanks.