Support for "esbuild-jest"

[makoru-hikage]

This is for projects using React which requires es6 builds. React projects typically uses ES6 builds.

[glennsl]

What would be required for this?

[makoru-hikage]

Thank you for your reply! Fortunately, you do not need to do any additional code changes for this. I initially thought you would need to.

I just needed to add this in a Jest config file (or "jest" property if you are storing your Jest config in package.json):

{
    "transform": {
      "^.+\\.jsx?$": "esbuild-jest"
    },
    "transformIgnorePatterns": ["<rootDir>/node_modules/(?!(rescript|@glennsl/bs-jest)/)"]
  }

This will require "esbuild-jest" of course. When someone uses rescript build -with-deps with this property in bsconfig.json:

"package-specs": {
    "module": "es6",
    "in-source": true
  }

All res* and ml* files are transpiled into js (or mjs) in ES6 flavor. However, the compiled res/ml files in node_modules aren't transpiled, so this thing "transformIgnorePatterns": ["<rootDir>/node_modules/(?!(rescript|@glennsl/bs-jest)/)"] is added to the Jest config.

Shall I add something to the docs?

[makoru-hikage]

Please take note that I have not done any test files involving React. I use it here: https://github.com/makoru-hikage/sasquare-reasonml

(Please do not mind that misnomer on my personal project.)

[glennsl]

Thanks for the explanation!

Shall I add something to the docs?

Yes. Please do! As a sub-heading to the troubleshooting section, for example, or just referencing this issue if you're feeling lazy.

[makoru-hikage]

Thank you! I shall write a sub-heading, submit a PR and close this upon merging.

[glennsl]

Closing this as resolved in #91 then. Thanks again!