move runPluginFromDefaultHandler to new Runtime class

src/Compile/DefaultHandlerFunctionCallCompiler.php

@@ -44,7 +44,7 @@ class DefaultHandlerFunctionCallCompiler extends Base {
 		}
 		$_params = 'array(' . implode(',', $_paramsArray) . ')';
 
-		$output = "\$_smarty_tpl->smarty->runPluginFromDefaultHandler(" . var_export($function, true) .
+		$output = "\$_smarty_tpl->smarty->getRuntime('DefaultPluginHandler')->runPlugin(" . var_export($function, true) .
 			",'function',$_params, \$_smarty_tpl)";
 
 		if (!empty($parameter['modifierlist'])) {

src/Runtime/DefaultPluginHandlerRuntime.php

@@ -0,0 +1,48 @@
+<?php
+
+namespace Smarty\Runtime;
+
+use Smarty\Exception;
+
+class DefaultPluginHandlerRuntime {
+
+	/**
+	 * @var callable
+	 */
+	private $defaultPluginHandler;
+
+	public function __construct(?callable $defaultPluginHandler = null) {
+		$this->defaultPluginHandler = $defaultPluginHandler;
+	}
+
+	/**
+	 * @throws Exception
+	 */
+	public function runPlugin($tag, $plugin_type, $params, \Smarty\Template $template) {
+
+		if ($this->defaultPluginHandler === null) {
+			return false;
+		}
+
+		$callback = null;
+
+		// these are not used here
+		$script = null;
+		$cacheable = null;
+
+		if (call_user_func_array(
+				$this->defaultPluginHandler,
+				[
+					$tag,
+					$plugin_type,
+					null, // This used to pass $this->template, but this parameter has been removed in 5.0
+					&$callback,
+					&$script,
+					&$cacheable,
+				]
+			) && $callback) {
+			return $callback($params, $template);
+		}
+		throw new Exception("Default plugin handler: Returned callback for '{$tag}' not callable at runtime");
+	}
+}

src/Smarty.php

@@ -2075,6 +2075,10 @@ class Smarty extends \Smarty\TemplateBase
 				return $this->runtimes[$type] = new \Smarty\Runtime\MakeNocacheRuntime();
 			case 'TplFunction':
 				return $this->runtimes[$type] = new \Smarty\Runtime\TplFunctionRuntime();
+			case 'DefaultPluginHandler':
+				return $this->runtimes[$type] = new \Smarty\Runtime\DefaultPluginHandlerRuntime(
+					$this->getDefaultPluginHandlerFunc()
+				);
 		}
 
 		throw new \Smarty\Exception('Trying to load invalid runtime ' . $type);
@@ -2103,31 +2107,6 @@ class Smarty extends \Smarty\TemplateBase
 		return $this->default_plugin_handler_func;
 	}
 
-	public function runPluginFromDefaultHandler($tag, $plugin_type, $params, \Smarty\Template $template) {
-		$defaultPluginHandlerFunc = $this->getDefaultPluginHandlerFunc();
-
-		$callback = null;
-
-		// these are not used here
-		$script = null;
-		$cacheable = null;
-
-		if (call_user_func_array(
-			$defaultPluginHandlerFunc,
-			[
-				$tag,
-				$plugin_type,
-				null, // This used to pass $this->template, but this parameter has been removed in 5.0
-				&$callback,
-				&$script,
-				&$cacheable,
-			]
-		) && $callback) {
-			return $callback($params, $template);
-		}
-		throw new Exception("Default plugin handler: Returned callback for '{$tag}' not callable at runtime");
-	}
-
 	/**
 	 * load a filter of specified type and name
 	 *