[v5] jest fails to run

I’ve just bumped my code to v5 as I’m currently experiencing the #65 bug often. My tests dont run however (detail below). I’m guessing this is because the current build target and module ts settings are super modern.

Could they be downgraded to "target":"es5" and "module": "commonjs" ?

ps congrats on the first v5 alpha!

  ● Test suite failed to run

    Jest encountered an unexpected token

    This usually means that you are trying to import a file which Jest cannot parse, e.g. it's not plain JavaScript.

    By default, if Jest sees a Babel config, it will use that to transform your files, ignoring "node_modules".

    Here's what you can do:
     • If you are trying to use ECMAScript Modules, see https://jestjs.io/docs/en/ecmascript-modules for how to enable it.
     • To have some of your "node_modules" files transformed, you can specify a custom "transformIgnorePatterns" in your config.
     • If you need a custom transformation specify a "transform" option in your config.
     • If you simply want to mock your non-JS modules (e.g. binary assets) you can stub them out with the "moduleNameMapper" config option.

    You'll find more details and examples of these config options in the docs:
    https://jestjs.io/docs/en/configuration.html

    Details:

    /home/circleci/project/node_modules/redlock/dist/index.js:1
    ({"Object.<anonymous>":function(module,exports,require,__dirname,__filename,global,jest){import { randomBytes, createHash } from "crypto";
                                                                                             ^^^^^^

    SyntaxError: Cannot use import statement outside a module

    > 1 | import Redlock, { Lock } from "redlock";

[SimenB]

Jest executes all code in a vm, and vm’s support for ESM is sorta sketchy still (see first link in the error in the OP: https://jestjs.io/docs/ecmascript-modules)

Best solution for Jest here is to ship a CJS implementation (in addition to the ESM one) referenced in main and using exports for the ESM one: https://nodejs.org/api/packages.html#packages_package_entry_points

(note that Jest does not support this field yet, which is why main is still needed)

[mike-marcacci]

I just published v5.0.0-beta.1 which should fix this.