add json encoding exception

src/Illuminate/Database/Eloquent/JsonEncodingException.php

@@ -0,0 +1,20 @@
+<?php
+
+namespace Illuminate\Database\Eloquent;
+
+use RuntimeException;
+
+class JsonEncodingException extends RuntimeException
+{
+    /**
+     * Create a new JSON encoding exception for the model.
+     *
+     * @param  mixed  $model
+     * @param  string  $message
+     * @return static
+     */
+    public static function forModel($model, $message)
+    {
+        return new static('Error encoding model ['.get_class($model).'] with ID ['.$model->getKey().'] to JSON: '.$message);
+    }
+}

src/Illuminate/Database/Eloquent/Model.php

@@ -2415,14 +2415,14 @@ public function setIncrementing($value)
      * @param  int  $options
      * @return string
      *
-     * @throws \InvalidArgumentException
+     * @throws JsonEncodingException
      */
     public function toJson($options = 0)
     {
         $json = json_encode($this->jsonSerialize(), $options);
 
         if (JSON_ERROR_NONE !== json_last_error()) {
-            throw new InvalidArgumentException(json_last_error_msg());
+            throw JsonEncodingException::forModel($this, json_last_error_msg());
         }
 
         return $json;