Transform require/import syntax of "externals" to match output format?

[popeindustries]

Presently (0.8.17), when marking a dependency as external (via externals argument or custom onResolve plugin), the original import syntax is preserved instead of being transformed to match that of the output format.

For example, when bundling a cjs file to esm:

const ms = require('ms');
module.exports = ms('10m');

...with externals: ['ms'] and format: 'esm' results in:

var __commonJS = (callback, module) => () => {
  if (!module) {
    module = {exports: {}};
    callback(module.exports, module);
  }
  return module.exports;
};

// input.js
var require_input = __commonJS((exports) => {
  var ms = require("ms");
  exports.dep = ms("10m");
});
export default require_input();

...which preserves the original var ms = require("ms") instead of transforming to import ms from "ms" to match the output format.

Perhaps it's out of scope, but fixing something like this in user space, without access to the AST, would be quite error prone.

[evanw]

This is a duplicate of #566.

fixing something like this in user space, without access to the AST, would be quite error prone

It's actually easy to do this with a plugin: #566 (comment).

[popeindustries]

Sorry for the duplicate! I'll take a look at the plugin solution.