Fix with closue value implementation.

Use filteredQuery as callback parameter.
Fix #1752

Author: yajra

src/DataTableAbstract.php

@@ -340,7 +340,7 @@ public function with($key, $value = '')
         if (is_array($key)) {
             $this->appends = $key;
         } elseif (is_callable($value)) {
-            $this->appends[$key] = value($value);
+            $this->appends[$key] = $value;
         } else {
             $this->appends[$key] = value($value);
         }
@@ -683,12 +683,12 @@ protected function processResults($results, $object = false)
      */
     protected function render(array $data)
     {
-        $output = array_merge([
+        $output = $this->attachAppends([
             'draw'            => (int) $this->request->input('draw'),
             'recordsTotal'    => $this->totalRecords,
             'recordsFiltered' => $this->filteredRecords,
             'data'            => $data,
-        ], $this->appends);
+        ]);
 
         if ($this->config->isDebugging()) {
             $output = $this->showDebugger($output);
@@ -702,6 +702,17 @@ protected function render(array $data)
         );
     }
 
+    /**
+     * Attach custom with meta on response.
+     *
+     * @param array $data
+     * @return array
+     */
+    protected function attachAppends(array $data)
+    {
+        return array_merge($data, $this->appends);
+    }
+
     /**
      * Append debug parameters on output.
      *

src/QueryDataTable.php

@@ -669,4 +669,23 @@ protected function showDebugger(array $output)
 
         return $output;
     }
+
+    /**
+     * Attach custom with meta on response.
+     *
+     * @param array $data
+     * @return array
+     */
+    protected function attachAppends(array $data)
+    {
+        $appends = [];
+        foreach ($this->appends as $key => $value) {
+            if (is_callable($value)) {
+                $appends[$key] = value($value($this->getFilteredQuery()));
+            } else {
+                $appends[$key] = $value;
+            }
+        }
+        return array_merge($data, $appends);
+    }
 }