ErrorException: Creating default object from empty value

I created table migrations in Laravel using php artisan migrate:make. When I tried to create the tables in the database, I got an error:

[ErrorException] 
Creating default object from empty value

What is this related to? No tables are created nor can I find any errors in my migrations.

I have 25 tables in the migrations folder, all look similar to this.

<?php

use Illuminate\Database\Schema\Blueprint;
use Illuminate\Database\Migrations\Migration;

class CreateAddressesTable extends Migration {
    public function up() {
        Schema::create("addresses", function() {
            $table->engine = "InnoDB";

            $table->increments("id");
            $table->integer("user_id")->unsigned();

            $table->string("street");
            $table->string("city");
            $table->integer("postal_code")->unsigned();

            $table->foreign("user_id")->references("id")->on("users");

            $table->softDeletes();
            $table->timestamps();
        });
    }

    public function down() {
        Schema::dropIfExists("addresses");
    }
}