Update Twig from 1.35.0 to 1.42.4 (PHP 5.5 is now required!)

This fixes some errors on PHP 7.4 and contains even more fixes
Also bumped PHP version to 5.5 as Twig requires it.

system/libs/Twig/Loader/ArrayLoader.php

@@ -9,6 +9,11 @@
  * file that was distributed with this source code.
  */
 
+namespace Twig\Loader;
+
+use Twig\Error\LoaderError;
+use Twig\Source;
+
 /**
  * Loads a template from an array.
  *
@@ -23,14 +28,14 @@
  *
  * @author Fabien Potencier <fabien@symfony.com>
  */
-class Twig_Loader_Array implements Twig_LoaderInterface, Twig_ExistsLoaderInterface, Twig_SourceContextLoaderInterface
+class ArrayLoader implements LoaderInterface, ExistsLoaderInterface, SourceContextLoaderInterface
 {
-    protected $templates = array();
+    protected $templates = [];
 
     /**
      * @param array $templates An array of templates (keys are the names, and values are the source code)
      */
-    public function __construct(array $templates = array())
+    public function __construct(array $templates = [])
     {
         $this->templates = $templates;
     }
@@ -48,11 +53,11 @@ class Twig_Loader_Array implements Twig_LoaderInterface, Twig_ExistsLoaderInterf
 
     public function getSource($name)
     {
-        @trigger_error(sprintf('Calling "getSource" on "%s" is deprecated since 1.27. Use getSourceContext() instead.', get_class($this)), E_USER_DEPRECATED);
+        @trigger_error(sprintf('Calling "getSource" on "%s" is deprecated since 1.27. Use getSourceContext() instead.', \get_class($this)), E_USER_DEPRECATED);
 
         $name = (string) $name;
         if (!isset($this->templates[$name])) {
-            throw new Twig_Error_Loader(sprintf('Template "%s" is not defined.', $name));
+            throw new LoaderError(sprintf('Template "%s" is not defined.', $name));
         }
 
         return $this->templates[$name];
@@ -62,10 +67,10 @@ class Twig_Loader_Array implements Twig_LoaderInterface, Twig_ExistsLoaderInterf
     {
         $name = (string) $name;
         if (!isset($this->templates[$name])) {
-            throw new Twig_Error_Loader(sprintf('Template "%s" is not defined.', $name));
+            throw new LoaderError(sprintf('Template "%s" is not defined.', $name));
         }
 
-        return new Twig_Source($this->templates[$name], $name);
+        return new Source($this->templates[$name], $name);
     }
 
     public function exists($name)
@@ -77,7 +82,7 @@ class Twig_Loader_Array implements Twig_LoaderInterface, Twig_ExistsLoaderInterf
     {
         $name = (string) $name;
         if (!isset($this->templates[$name])) {
-            throw new Twig_Error_Loader(sprintf('Template "%s" is not defined.', $name));
+            throw new LoaderError(sprintf('Template "%s" is not defined.', $name));
         }
 
         return $name.':'.$this->templates[$name];
@@ -87,11 +92,11 @@ class Twig_Loader_Array implements Twig_LoaderInterface, Twig_ExistsLoaderInterf
     {
         $name = (string) $name;
         if (!isset($this->templates[$name])) {
-            throw new Twig_Error_Loader(sprintf('Template "%s" is not defined.', $name));
+            throw new LoaderError(sprintf('Template "%s" is not defined.', $name));
         }
 
         return true;
     }
 }
 
-class_alias('Twig_Loader_Array', 'Twig\Loader\ArrayLoader', false);
+class_alias('Twig\Loader\ArrayLoader', 'Twig_Loader_Array');

system/libs/Twig/Loader/ChainLoader.php

@@ -9,6 +9,11 @@
  * file that was distributed with this source code.
  */
 
+namespace Twig\Loader;
+
+use Twig\Error\LoaderError;
+use Twig\Source;
+
 /**
  * Loads templates from other loaders.
  *
@@ -16,67 +21,75 @@
  *
  * @author Fabien Potencier <fabien@symfony.com>
  */
-class Twig_Loader_Chain implements Twig_LoaderInterface, Twig_ExistsLoaderInterface, Twig_SourceContextLoaderInterface
+class ChainLoader implements LoaderInterface, ExistsLoaderInterface, SourceContextLoaderInterface
 {
-    private $hasSourceCache = array();
-    protected $loaders = array();
+    private $hasSourceCache = [];
+    protected $loaders = [];
 
     /**
-     * @param Twig_LoaderInterface[] $loaders
+     * @param LoaderInterface[] $loaders
      */
-    public function __construct(array $loaders = array())
+    public function __construct(array $loaders = [])
     {
         foreach ($loaders as $loader) {
             $this->addLoader($loader);
         }
     }
 
-    public function addLoader(Twig_LoaderInterface $loader)
+    public function addLoader(LoaderInterface $loader)
     {
         $this->loaders[] = $loader;
-        $this->hasSourceCache = array();
+        $this->hasSourceCache = [];
+    }
+
+    /**
+     * @return LoaderInterface[]
+     */
+    public function getLoaders()
+    {
+        return $this->loaders;
     }
 
     public function getSource($name)
     {
-        @trigger_error(sprintf('Calling "getSource" on "%s" is deprecated since 1.27. Use getSourceContext() instead.', get_class($this)), E_USER_DEPRECATED);
+        @trigger_error(sprintf('Calling "getSource" on "%s" is deprecated since 1.27. Use getSourceContext() instead.', \get_class($this)), E_USER_DEPRECATED);
 
-        $exceptions = array();
+        $exceptions = [];
         foreach ($this->loaders as $loader) {
-            if ($loader instanceof Twig_ExistsLoaderInterface && !$loader->exists($name)) {
+            if ($loader instanceof ExistsLoaderInterface && !$loader->exists($name)) {
                 continue;
             }
 
             try {
                 return $loader->getSource($name);
-            } catch (Twig_Error_Loader $e) {
+            } catch (LoaderError $e) {
                 $exceptions[] = $e->getMessage();
             }
         }
 
-        throw new Twig_Error_Loader(sprintf('Template "%s" is not defined%s.', $name, $exceptions ? ' ('.implode(', ', $exceptions).')' : ''));
+        throw new LoaderError(sprintf('Template "%s" is not defined%s.', $name, $exceptions ? ' ('.implode(', ', $exceptions).')' : ''));
     }
 
     public function getSourceContext($name)
     {
-        $exceptions = array();
+        $exceptions = [];
         foreach ($this->loaders as $loader) {
-            if ($loader instanceof Twig_ExistsLoaderInterface && !$loader->exists($name)) {
+            if ($loader instanceof ExistsLoaderInterface && !$loader->exists($name)) {
                 continue;
             }
 
             try {
-                if ($loader instanceof Twig_SourceContextLoaderInterface) {
+                if ($loader instanceof SourceContextLoaderInterface) {
                     return $loader->getSourceContext($name);
                 }
 
-                return new Twig_Source($loader->getSource($name), $name);
-            } catch (Twig_Error_Loader $e) {
+                return new Source($loader->getSource($name), $name);
+            } catch (LoaderError $e) {
                 $exceptions[] = $e->getMessage();
             }
         }
 
-        throw new Twig_Error_Loader(sprintf('Template "%s" is not defined%s.', $name, $exceptions ? ' ('.implode(', ', $exceptions).')' : ''));
+        throw new LoaderError(sprintf('Template "%s" is not defined%s.', $name, $exceptions ? ' ('.implode(', ', $exceptions).')' : ''));
     }
 
     public function exists($name)
@@ -88,7 +101,7 @@ class Twig_Loader_Chain implements Twig_LoaderInterface, Twig_ExistsLoaderInterf
         }
 
         foreach ($this->loaders as $loader) {
-            if ($loader instanceof Twig_ExistsLoaderInterface) {
+            if ($loader instanceof ExistsLoaderInterface) {
                 if ($loader->exists($name)) {
                     return $this->hasSourceCache[$name] = true;
                 }
@@ -97,14 +110,14 @@ class Twig_Loader_Chain implements Twig_LoaderInterface, Twig_ExistsLoaderInterf
             }
 
             try {
-                if ($loader instanceof Twig_SourceContextLoaderInterface) {
+                if ($loader instanceof SourceContextLoaderInterface) {
                     $loader->getSourceContext($name);
                 } else {
                     $loader->getSource($name);
                 }
 
                 return $this->hasSourceCache[$name] = true;
-            } catch (Twig_Error_Loader $e) {
+            } catch (LoaderError $e) {
             }
         }
 
@@ -113,39 +126,39 @@ class Twig_Loader_Chain implements Twig_LoaderInterface, Twig_ExistsLoaderInterf
 
     public function getCacheKey($name)
     {
-        $exceptions = array();
+        $exceptions = [];
         foreach ($this->loaders as $loader) {
-            if ($loader instanceof Twig_ExistsLoaderInterface && !$loader->exists($name)) {
+            if ($loader instanceof ExistsLoaderInterface && !$loader->exists($name)) {
                 continue;
             }
 
             try {
                 return $loader->getCacheKey($name);
-            } catch (Twig_Error_Loader $e) {
-                $exceptions[] = get_class($loader).': '.$e->getMessage();
+            } catch (LoaderError $e) {
+                $exceptions[] = \get_class($loader).': '.$e->getMessage();
             }
         }
 
-        throw new Twig_Error_Loader(sprintf('Template "%s" is not defined%s.', $name, $exceptions ? ' ('.implode(', ', $exceptions).')' : ''));
+        throw new LoaderError(sprintf('Template "%s" is not defined%s.', $name, $exceptions ? ' ('.implode(', ', $exceptions).')' : ''));
     }
 
     public function isFresh($name, $time)
     {
-        $exceptions = array();
+        $exceptions = [];
         foreach ($this->loaders as $loader) {
-            if ($loader instanceof Twig_ExistsLoaderInterface && !$loader->exists($name)) {
+            if ($loader instanceof ExistsLoaderInterface && !$loader->exists($name)) {
                 continue;
             }
 
             try {
                 return $loader->isFresh($name, $time);
-            } catch (Twig_Error_Loader $e) {
-                $exceptions[] = get_class($loader).': '.$e->getMessage();
+            } catch (LoaderError $e) {
+                $exceptions[] = \get_class($loader).': '.$e->getMessage();
             }
         }
 
-        throw new Twig_Error_Loader(sprintf('Template "%s" is not defined%s.', $name, $exceptions ? ' ('.implode(', ', $exceptions).')' : ''));
+        throw new LoaderError(sprintf('Template "%s" is not defined%s.', $name, $exceptions ? ' ('.implode(', ', $exceptions).')' : ''));
     }
 }
 
-class_alias('Twig_Loader_Chain', 'Twig\Loader\ChainLoader', false);
+class_alias('Twig\Loader\ChainLoader', 'Twig_Loader_Chain');

system/libs/Twig/Loader/ExistsLoaderInterface.php

@@ -0,0 +1,33 @@
+<?php
+
+/*
+ * This file is part of Twig.
+ *
+ * (c) Fabien Potencier
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Twig\Loader;
+
+/**
+ * Adds an exists() method for loaders.
+ *
+ * @author Florin Patan <florinpatan@gmail.com>
+ *
+ * @deprecated since 1.12 (to be removed in 3.0)
+ */
+interface ExistsLoaderInterface
+{
+    /**
+     * Check if we have the source code of a template, given its name.
+     *
+     * @param string $name The name of the template to check if we can load
+     *
+     * @return bool If the template source code is handled by this loader or not
+     */
+    public function exists($name);
+}
+
+class_alias('Twig\Loader\ExistsLoaderInterface', 'Twig_ExistsLoaderInterface');

system/libs/Twig/Loader/FilesystemLoader.php

@@ -9,19 +9,24 @@
  * file that was distributed with this source code.
  */
 
+namespace Twig\Loader;
+
+use Twig\Error\LoaderError;
+use Twig\Source;
+
 /**
  * Loads template from the filesystem.
  *
  * @author Fabien Potencier <fabien@symfony.com>
  */
-class Twig_Loader_Filesystem implements Twig_LoaderInterface, Twig_ExistsLoaderInterface, Twig_SourceContextLoaderInterface
+class FilesystemLoader implements LoaderInterface, ExistsLoaderInterface, SourceContextLoaderInterface
 {
     /** Identifier of the main namespace. */
     const MAIN_NAMESPACE = '__main__';
 
-    protected $paths = array();
-    protected $cache = array();
-    protected $errorCache = array();
+    protected $paths = [];
+    protected $cache = [];
+    protected $errorCache = [];
 
     private $rootPath;
 
@@ -29,11 +34,11 @@ class Twig_Loader_Filesystem implements Twig_LoaderInterface, Twig_ExistsLoaderI
      * @param string|array $paths    A path or an array of paths where to look for templates
      * @param string|null  $rootPath The root path common to all relative paths (null for getcwd())
      */
-    public function __construct($paths = array(), $rootPath = null)
+    public function __construct($paths = [], $rootPath = null)
     {
-        $this->rootPath = (null === $rootPath ? getcwd() : $rootPath).DIRECTORY_SEPARATOR;
+        $this->rootPath = (null === $rootPath ? getcwd() : $rootPath).\DIRECTORY_SEPARATOR;
         if (false !== $realPath = realpath($rootPath)) {
-            $this->rootPath = $realPath.DIRECTORY_SEPARATOR;
+            $this->rootPath = $realPath.\DIRECTORY_SEPARATOR;
         }
 
         if ($paths) {
@@ -50,7 +55,7 @@ class Twig_Loader_Filesystem implements Twig_LoaderInterface, Twig_ExistsLoaderI
      */
     public function getPaths($namespace = self::MAIN_NAMESPACE)
     {
-        return isset($this->paths[$namespace]) ? $this->paths[$namespace] : array();
+        return isset($this->paths[$namespace]) ? $this->paths[$namespace] : [];
     }
 
     /**
@@ -73,11 +78,11 @@ class Twig_Loader_Filesystem implements Twig_LoaderInterface, Twig_ExistsLoaderI
      */
     public function setPaths($paths, $namespace = self::MAIN_NAMESPACE)
     {
-        if (!is_array($paths)) {
-            $paths = array($paths);
+        if (!\is_array($paths)) {
+            $paths = [$paths];
         }
 
-        $this->paths[$namespace] = array();
+        $this->paths[$namespace] = [];
         foreach ($paths as $path) {
             $this->addPath($path, $namespace);
         }
@@ -89,16 +94,16 @@ class Twig_Loader_Filesystem implements Twig_LoaderInterface, Twig_ExistsLoaderI
      * @param string $path      A path where to look for templates
      * @param string $namespace A path namespace
      *
-     * @throws Twig_Error_Loader
+     * @throws LoaderError
      */
     public function addPath($path, $namespace = self::MAIN_NAMESPACE)
     {
         // invalidate the cache
-        $this->cache = $this->errorCache = array();
+        $this->cache = $this->errorCache = [];
 
         $checkPath = $this->isAbsolutePath($path) ? $path : $this->rootPath.$path;
         if (!is_dir($checkPath)) {
-            throw new Twig_Error_Loader(sprintf('The "%s" directory does not exist ("%s").', $path, $checkPath));
+            throw new LoaderError(sprintf('The "%s" directory does not exist ("%s").', $path, $checkPath));
         }
 
         $this->paths[$namespace][] = rtrim($path, '/\\');
@@ -110,16 +115,16 @@ class Twig_Loader_Filesystem implements Twig_LoaderInterface, Twig_ExistsLoaderI
      * @param string $path      A path where to look for templates
      * @param string $namespace A path namespace
      *
-     * @throws Twig_Error_Loader
+     * @throws LoaderError
      */
     public function prependPath($path, $namespace = self::MAIN_NAMESPACE)
     {
         // invalidate the cache
-        $this->cache = $this->errorCache = array();
+        $this->cache = $this->errorCache = [];
 
         $checkPath = $this->isAbsolutePath($path) ? $path : $this->rootPath.$path;
         if (!is_dir($checkPath)) {
-            throw new Twig_Error_Loader(sprintf('The "%s" directory does not exist ("%s").', $path, $checkPath));
+            throw new LoaderError(sprintf('The "%s" directory does not exist ("%s").', $path, $checkPath));
         }
 
         $path = rtrim($path, '/\\');
@@ -133,22 +138,30 @@ class Twig_Loader_Filesystem implements Twig_LoaderInterface, Twig_ExistsLoaderI
 
     public function getSource($name)
     {
-        @trigger_error(sprintf('Calling "getSource" on "%s" is deprecated since 1.27. Use getSourceContext() instead.', get_class($this)), E_USER_DEPRECATED);
+        @trigger_error(sprintf('Calling "getSource" on "%s" is deprecated since 1.27. Use getSourceContext() instead.', \get_class($this)), E_USER_DEPRECATED);
 
-        return file_get_contents($this->findTemplate($name));
+        if (null === ($path = $this->findTemplate($name)) || false === $path) {
+            return '';
+        }
+
+        return file_get_contents($path);
     }
 
     public function getSourceContext($name)
     {
-        $path = $this->findTemplate($name);
+        if (null === ($path = $this->findTemplate($name)) || false === $path) {
+            return new Source('', $name, '');
+        }
 
-        return new Twig_Source(file_get_contents($path), $name, $path);
+        return new Source(file_get_contents($path), $name, $path);
     }
 
     public function getCacheKey($name)
     {
-        $path = $this->findTemplate($name);
-        $len = strlen($this->rootPath);
+        if (null === ($path = $this->findTemplate($name)) || false === $path) {
+            return '';
+        }
+        $len = \strlen($this->rootPath);
         if (0 === strncmp($this->rootPath, $path, $len)) {
             return substr($path, $len);
         }
@@ -165,9 +178,9 @@ class Twig_Loader_Filesystem implements Twig_LoaderInterface, Twig_ExistsLoaderI
         }
 
         try {
-            return false !== $this->findTemplate($name, false);
-        } catch (Twig_Error_Loader $exception) {
-            @trigger_error(sprintf('In %s::findTemplate(), you must accept a second argument that when set to "false" returns "false" instead of throwing an exception. Not supporting this argument is deprecated since version 1.27.', get_class($this)), E_USER_DEPRECATED);
+            return null !== ($path = $this->findTemplate($name, false)) && false !== $path;
+        } catch (LoaderError $e) {
+            @trigger_error(sprintf('In %s::findTemplate(), you must accept a second argument that when set to "false" returns "false" instead of throwing an exception. Not supporting this argument is deprecated since version 1.27.', \get_class($this)), E_USER_DEPRECATED);
 
             return false;
         }
@@ -175,12 +188,24 @@ class Twig_Loader_Filesystem implements Twig_LoaderInterface, Twig_ExistsLoaderI
 
     public function isFresh($name, $time)
     {
-        return filemtime($this->findTemplate($name)) <= $time;
+        // false support to be removed in 3.0
+        if (null === ($path = $this->findTemplate($name)) || false === $path) {
+            return false;
+        }
+
+        return filemtime($path) < $time;
     }
 
+    /**
+     * Checks if the template can be found.
+     *
+     * @param string $name The template name
+     *
+     * @return string|false|null The template name or false/null
+     */
     protected function findTemplate($name)
     {
-        $throw = func_num_args() > 1 ? func_get_arg(1) : true;
+        $throw = \func_num_args() > 1 ? func_get_arg(1) : true;
         $name = $this->normalizeName($name);
 
         if (isset($this->cache[$name])) {
@@ -192,12 +217,20 @@ class Twig_Loader_Filesystem implements Twig_LoaderInterface, Twig_ExistsLoaderI
                 return false;
             }
 
-            throw new Twig_Error_Loader($this->errorCache[$name]);
+            throw new LoaderError($this->errorCache[$name]);
         }
 
-        $this->validateName($name);
+        try {
+            $this->validateName($name);
 
-        list($namespace, $shortname) = $this->parseName($name);
+            list($namespace, $shortname) = $this->parseName($name);
+        } catch (LoaderError $e) {
+            if (!$throw) {
+                return false;
+            }
+
+            throw $e;
+        }
 
         if (!isset($this->paths[$namespace])) {
             $this->errorCache[$name] = sprintf('There are no registered paths for namespace "%s".', $namespace);
@@ -206,12 +239,12 @@ class Twig_Loader_Filesystem implements Twig_LoaderInterface, Twig_ExistsLoaderI
                 return false;
             }
 
-            throw new Twig_Error_Loader($this->errorCache[$name]);
+            throw new LoaderError($this->errorCache[$name]);
         }
 
         foreach ($this->paths[$namespace] as $path) {
             if (!$this->isAbsolutePath($path)) {
-                $path = $this->rootPath.'/'.$path;
+                $path = $this->rootPath.$path;
             }
 
             if (is_file($path.'/'.$shortname)) {
@@ -229,23 +262,23 @@ class Twig_Loader_Filesystem implements Twig_LoaderInterface, Twig_ExistsLoaderI
             return false;
         }
 
-        throw new Twig_Error_Loader($this->errorCache[$name]);
+        throw new LoaderError($this->errorCache[$name]);
     }
 
     protected function parseName($name, $default = self::MAIN_NAMESPACE)
     {
         if (isset($name[0]) && '@' == $name[0]) {
             if (false === $pos = strpos($name, '/')) {
-                throw new Twig_Error_Loader(sprintf('Malformed namespaced template name "%s" (expecting "@namespace/template_name").', $name));
+                throw new LoaderError(sprintf('Malformed namespaced template name "%s" (expecting "@namespace/template_name").', $name));
             }
 
             $namespace = substr($name, 1, $pos - 1);
             $shortname = substr($name, $pos + 1);
 
-            return array($namespace, $shortname);
+            return [$namespace, $shortname];
         }
 
-        return array($default, $name);
+        return [$default, $name];
     }
 
     protected function normalizeName($name)
@@ -256,7 +289,7 @@ class Twig_Loader_Filesystem implements Twig_LoaderInterface, Twig_ExistsLoaderI
     protected function validateName($name)
     {
         if (false !== strpos($name, "\0")) {
-            throw new Twig_Error_Loader('A template name cannot contain NUL bytes.');
+            throw new LoaderError('A template name cannot contain NUL bytes.');
         }
 
         $name = ltrim($name, '/');
@@ -270,7 +303,7 @@ class Twig_Loader_Filesystem implements Twig_LoaderInterface, Twig_ExistsLoaderI
             }
 
             if ($level < 0) {
-                throw new Twig_Error_Loader(sprintf('Looks like you try to load a template outside configured directories (%s).', $name));
+                throw new LoaderError(sprintf('Looks like you try to load a template outside configured directories (%s).', $name));
             }
         }
     }
@@ -278,8 +311,8 @@ class Twig_Loader_Filesystem implements Twig_LoaderInterface, Twig_ExistsLoaderI
     private function isAbsolutePath($file)
     {
         return strspn($file, '/\\', 0, 1)
-            || (strlen($file) > 3 && ctype_alpha($file[0])
-                && substr($file, 1, 1) === ':'
+            || (\strlen($file) > 3 && ctype_alpha($file[0])
+                && ':' === substr($file, 1, 1)
                 && strspn($file, '/\\', 2, 1)
             )
             || null !== parse_url($file, PHP_URL_SCHEME)
@@ -287,4 +320,4 @@ class Twig_Loader_Filesystem implements Twig_LoaderInterface, Twig_ExistsLoaderI
     }
 }
 
-class_alias('Twig_Loader_Filesystem', 'Twig\Loader\FilesystemLoader', false);
+class_alias('Twig\Loader\FilesystemLoader', 'Twig_Loader_Filesystem');

system/libs/Twig/Loader/LoaderInterface.php

@@ -0,0 +1,61 @@
+<?php
+
+/*
+ * This file is part of Twig.
+ *
+ * (c) Fabien Potencier
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Twig\Loader;
+
+use Twig\Error\LoaderError;
+
+/**
+ * Interface all loaders must implement.
+ *
+ * @author Fabien Potencier <fabien@symfony.com>
+ */
+interface LoaderInterface
+{
+    /**
+     * Gets the source code of a template, given its name.
+     *
+     * @param string $name The name of the template to load
+     *
+     * @return string The template source code
+     *
+     * @throws LoaderError When $name is not found
+     *
+     * @deprecated since 1.27 (to be removed in 2.0), implement Twig\Loader\SourceContextLoaderInterface
+     */
+    public function getSource($name);
+
+    /**
+     * Gets the cache key to use for the cache for a given template name.
+     *
+     * @param string $name The name of the template to load
+     *
+     * @return string The cache key
+     *
+     * @throws LoaderError When $name is not found
+     */
+    public function getCacheKey($name);
+
+    /**
+     * Returns true if the template is still fresh.
+     *
+     * @param string $name The template name
+     * @param int    $time Timestamp of the last modification time of the
+     *                     cached template
+     *
+     * @return bool true if the template is fresh, false otherwise
+     *
+     * @throws LoaderError When $name is not found
+     */
+    public function isFresh($name, $time);
+}
+
+class_alias('Twig\Loader\LoaderInterface', 'Twig_LoaderInterface');

system/libs/Twig/Loader/SourceContextLoaderInterface.php

@@ -0,0 +1,38 @@
+<?php
+
+/*
+ * This file is part of Twig.
+ *
+ * (c) Fabien Potencier
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Twig\Loader;
+
+use Twig\Error\LoaderError;
+use Twig\Source;
+
+/**
+ * Adds a getSourceContext() method for loaders.
+ *
+ * @author Fabien Potencier <fabien@symfony.com>
+ *
+ * @deprecated since 1.27 (to be removed in 3.0)
+ */
+interface SourceContextLoaderInterface
+{
+    /**
+     * Returns the source context for a given template logical name.
+     *
+     * @param string $name The template logical name
+     *
+     * @return Source
+     *
+     * @throws LoaderError When $name is not found
+     */
+    public function getSourceContext($name);
+}
+
+class_alias('Twig\Loader\SourceContextLoaderInterface', 'Twig_SourceContextLoaderInterface');

system/libs/Twig/Loader/String.php

@@ -1,58 +0,0 @@
-<?php
-
-/*
- * This file is part of Twig.
- *
- * (c) Fabien Potencier
- *
- * For the full copyright and license information, please view the LICENSE
- * file that was distributed with this source code.
- */
-
-@trigger_error('The Twig_Loader_String class is deprecated since version 1.18.1 and will be removed in 2.0. Use Twig_Loader_Array instead or Twig_Environment::createTemplate().', E_USER_DEPRECATED);
-
-/**
- * Loads a template from a string.
- *
- * This loader should NEVER be used. It only exists for Twig internal purposes.
- *
- * When using this loader with a cache mechanism, you should know that a new cache
- * key is generated each time a template content "changes" (the cache key being the
- * source code of the template). If you don't want to see your cache grows out of
- * control, you need to take care of clearing the old cache file by yourself.
- *
- * @deprecated since 1.18.1 (to be removed in 2.0)
- *
- * @internal
- *
- * @author Fabien Potencier <fabien@symfony.com>
- */
-class Twig_Loader_String implements Twig_LoaderInterface, Twig_ExistsLoaderInterface, Twig_SourceContextLoaderInterface
-{
-    public function getSource($name)
-    {
-        @trigger_error(sprintf('Calling "getSource" on "%s" is deprecated since 1.27. Use getSourceContext() instead.', get_class($this)), E_USER_DEPRECATED);
-
-        return $name;
-    }
-
-    public function getSourceContext($name)
-    {
-        return new Twig_Source($name, $name);
-    }
-
-    public function exists($name)
-    {
-        return true;
-    }
-
-    public function getCacheKey($name)
-    {
-        return $name;
-    }
-
-    public function isFresh($name, $time)
-    {
-        return true;
-    }
-}