PhantomJS timeout triggered by ?: expression

[o0chapm]

An issue is seen when running blanket_mocha:frontend:

      this.attributes =
        _.extend(this.attributes || {},
          {serviceUrl: url + (url.indexOf("?") >= 0 ? "&" : "?") + postData});

results in PhantomJS error:
Warning: PhantomJS timed out, possibly due to a missing Mocha run() call. Use --force to continue.

Re-writing the expression clears the issue:

      var url = this.url(),
        postData = $.param(cartObject) + (postDataString ? postDataString : ""),
        index = url.indexOf("?"),
        separator = index < 0 ? "?" : "&";
      this.attributes = _.extend(this.attributes || {}, {
        serviceUrl: url + separator + postData
      });