title: Laravel collection->push() not working properly
body: <p>I want to collect product and push to the session cart.</p>
  
  <pre><code>$product= Product::find(1);
  $product2= Product::find(2);
  
  session(['cart' =&gt; collect($product)]);
  
  session(['cart' =&gt; session('cart')-&gt;push($product2)])
  </code></pre>
  
  <p>This is my output with some dummy data.</p>
  
  <pre><code>{
    "0": {
      "id": 2,
      "sku": "SKU914",
      "price": 1.0,
      "special_price": 0.91,
      "weight": 763,
      "barcode": "0434120288572",
      "created_at": "2020-01-31 14:39:53",
      "updated_at": "2020-01-31 14:39:53"
    },
    "id": 1,
    "sku": "SKU579",
    "price": 22.8,
    "special_price": 19.14,
    "weight": 478459,
    "barcode": "1390377688",
    "created_at": "2020-01-31 14:34:59",
    "updated_at": "2020-01-31 14:34:59"
  }
  </code></pre>
  
  <p>The second product ($product2) which I pushed become outside of the array.
  How should I do to make it like <code>"0": {}, "1": {}</code></p>