Installing ReactTestRenderer@15.4.0-rc.1 from npm just brings down an index.js file, the referenced lib folder does not exist.

'use strict';
var fs = require('fs');
var grunt = require('grunt');
var src = 'packages/react-test-renderer/';
var dest = 'build/packages/react-test-renderer/';
var modSrc = 'build/node_modules/react-test-renderer/lib';
var lib = dest + 'lib/';
function buildRelease() {
  if (grunt.file.exists(dest)) {
    grunt.file.delete(dest);
  }
  
  var mappings = [].concat(
    grunt.file.expandMapping('**/*', dest, {cwd: src}),
    grunt.file.expandMapping('**/*', lib, {cwd: modSrc}),
    grunt.file.expandMapping('{LICENSE,PATENTS}', dest)
  );
  mappings.forEach(function(mapping) {
    var mappingSrc = mapping.src[0];
    var mappingDest = mapping.dest;
    if (grunt.file.isDir(mappingSrc)) {
      grunt.file.mkdir(mappingDest);
    } else {
      grunt.file.copy(mappingSrc, mappingDest);
    }
  });
}
function packRelease() {