require in rollem.config.js doesn't work

When I am trying to import relative module, like it doesn't work. For example, the following rollem.config.js fails

import helper from './my-helper';

export default [/* ...entries... */]

Gives me an error Error: Cannot find module './my-helper.js'

It happens because you are using eval that uses require from the current module context, but not the original rollem.config.js location.

See how that was worked around in Rollup. I think that this trick with temporary replaced require hook should be ported there as well.

Reproduce the failure with the rollem.config.js example and its relative ./my-helper import. Read the Rollup runRollup.js workaround linked in the issue, then trace the eval/require handling in Rollem. Done means relative modules imported from rollem.config.js resolve from that configuration file's location.