babel-plugin-transform-import-extension/lib/index.js

Change the file extension in require calls when transpiling import statements

"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports["default"] = plugin;
var defaultOpts = {
  mjs: "js"
};

function plugin() {
  return {
    visitor: {
      ImportDeclaration: function ImportDeclaration(path, state) {
        var source = path.node.source;
        var value = source.value;
        var opts = state.opts;
        var origExts = Object.keys(opts);
        var newExtFrom = origExts.length ? opts : defaultOpts;
        origExts = Object.keys(newExtFrom);
        source.value = origExts.reduce(function (newValue, origExt) {
          return newValue.replace(new RegExp("^(\\..*\\.)".concat(origExt, "$")), "$1".concat(newExtFrom[origExt]));
        }, value);
      }
    }
  };
}