jest-resolver-esm/index.js

ESM resolver for Jest: use Webpack enhanced-resolver by default, with fallback to Jest resolver

const fs = require('fs');
const resolve = require('enhanced-resolve');

const enhanced = resolve.ResolverFactory.createResolver({
    fileSystem: new resolve.CachedInputFileSystem(fs, 4000),
    extensions: ['.js', '.json'],
    useSyncFileSystemCalls: true,
    conditionNames: ['node', 'import'],
});

module.exports = (request, options) => {
    try {
        return enhanced.resolveSync({}, options.basedir, request, {});
    } catch {
        // Call Jest default resolver
        return options.defaultResolver(request, options);
    }
};