Merge branch '1.x' into 2.x

* 1.x:
  Throw exception in case non-Traversable data is passed to "filter" filter
  Improve batch code example

doc/filters/batch.rst

@@ -7,7 +7,7 @@ missing items:
 
 .. code-block:: twig
 
-    {% set items = ['a', 'b', 'c', 'd', 'e', 'f', 'g'] %}
+    {% set items = ['a', 'b', 'c', 'd'] %}
 
     <table>
     {% for row in items|batch(3, 'No item') %}
@@ -31,11 +31,6 @@ The above example will be rendered as:
         </tr>
         <tr>
             <td>d</td>
-            <td>e</td>
-            <td>f</td>
-        </tr>
-        <tr>
-            <td>g</td>
             <td>No item</td>
             <td>No item</td>
         </tr>

src/Extension/CoreExtension.php

@@ -1537,6 +1537,10 @@ function twig_array_column($array, $name, $index = null): array
 
 function twig_array_filter($array, $arrow)
 {
+    if (!twig_test_iterable($array)) {
+        throw new RuntimeError(sprintf('The "filter" filter expects an array or "Traversable", got "%s".', \is_object($array) ? \get_class($array) : \gettype($array)));
+    }
+
     if (\is_array($array)) {
         return array_filter($array, $arrow, \ARRAY_FILTER_USE_BOTH);
     }