code: function (version) {
          let cachePath = path.join(ForestInternal.elmRoot(version), 'binpath.log');
          let promiseFn = function (resolve, reject) {
              fs.readFile(cachePath, 'utf-8', (err, data) => {
                  if (err) {
                      // TODO: Try to re-cache the result of `npm bin`
                      throw new ForestError(Errors.BinPathReadFailed, err.message);
                  }
                  else {
                      resolve(data.trim());
                  }
              });
          };
          return new Promise(promiseFn);
      }
docs: /* ****************************************************************************
  Get the result of `npm bin` in the container for a specific elm version