Fix code needed for SonataPageBundle (#1100)

src/Model/BaseBlock.php

@@ -199,6 +199,26 @@ public function addChildren(BlockInterface $children): void
         $children->setParent($this);
     }
 
+    public function removeChild(BlockInterface $child): void
+    {
+        // NEXT_MAJOR: Remove this condition, children will be a Collection.
+        if (\is_array($this->children)) {
+            $key = array_search($child, $this->children, true);
+
+            if (false === $key) {
+                return;
+            }
+
+            unset($this->children[$key]);
+
+            return;
+        }
+
+        if ($this->children->contains($child)) {
+            $this->children->removeElement($child);
+        }
+    }
+
     public function getChildren()
     {
         return $this->children;

src/Model/BlockInterface.php

@@ -17,6 +17,7 @@
 
 /**
  * @method void addChild(BlockInterface $child)
+ * @method void removeChild(BlockInterface $child)
  * @method bool hasChild()
  */
 interface BlockInterface

tests/Util/RecursiveBlockIteratorIteratorTest.php

@@ -28,6 +28,9 @@ public function testInterface(): void
 
         $block1->addChild($block2);
         $block1->addChild($block3);
+        $block1->removeChild($block3);
+        $block1->removeChild($block4);
+        $block1->addChild($block3);
 
         $i = new RecursiveBlockIteratorIterator([$block1, $block4]);