Jest can't transpile node_modules

Question

I am having the following error when running Jest

SyntaxError: node_modules/my_styleguide/src/components/blocks/SegmentSetting.jsx: Unexpected token (46:10)
  44 |         ) {
  45 |         return (
> 46 |           <p className="SettingDescr">{self.props.description}</p>
     |           ^
  47 |         )
  48 |       }
  49 |     }

The node_modules dependency is still in its es6 format. Jest doesn't seem to provide the option to transpile your node_modules, as it does with your actual app. Instead, jest ignores the node_modules folder.

The .bashrc file looks ok to me:

{
  "presets": ["es2015", "react", "stage-0"]
}

How do you make Jest transpile your node_modules too? It would be the equivalent of the "--ignore false" flag that we have in mocha.

Answer 1

I would mark this as an answer rather than the answer.

I had a similar issue, multiple components in node_modules in ES2015 and in need of transpilation.

I updated transformIgnorePatterns to:

["/node_modules/(?!(our-react-components-.*?\\.js$))"]

The negative look-ahead for modules in our-react-components-* folders mean Jest (and therefore Babel) will find and transpile our shared components.

This was in an ejected Create React App project with Jest 20.0.4.