Fix PHP 7.4 deprecations

inc/lib/IP/Lifo/IP/BC.php

@@ -102,7 +102,7 @@ abstract class BC
 
         $value = '';
         for ($i=0; $i<$len; $i++) {
-            $value .= (($left{$i} + 0) & ($right{$i} + 0)) ? '1' : '0';
+            $value .= (($left[$i] + 0) & ($right[$i] + 0)) ? '1' : '0';
         }
         return self::bcbindec($value != '' ? $value : '0');
     }
@@ -116,7 +116,7 @@ abstract class BC
 
         $value = '';
         for ($i=0; $i<$len; $i++) {
-            $value .= (($left{$i} + 0) | ($right{$i} + 0)) ? '1' : '0';
+            $value .= (($left[$i] + 0) | ($right[$i] + 0)) ? '1' : '0';
         }
         return self::bcbindec($value != '' ? $value : '0');
     }
@@ -130,7 +130,7 @@ abstract class BC
 
         $value = '';
         for ($i=0; $i<$len; $i++) {
-            $value .= (($left{$i} + 0) ^ ($right{$i} + 0)) ? '1' : '0';
+            $value .= (($left[$i] + 0) ^ ($right[$i] + 0)) ? '1' : '0';
         }
         return self::bcbindec($value != '' ? $value : '0');
     }
@@ -144,7 +144,7 @@ abstract class BC
         $len = self::_bitwise($left, $right, $bits);
         $value = '';
         for ($i=0; $i<$len; $i++) {
-            $value .= $left{$i} == '1' ? '0' : '1';
+            $value .= $left[$i] == '1' ? '0' : '1';
         }
         return self::bcbindec($value);
     }

inc/lib/Twig/Node.php

@@ -39,7 +39,7 @@ class Twig_Node implements Twig_NodeInterface
     {
         foreach ($nodes as $name => $node) {
             if (!$node instanceof Twig_NodeInterface) {
-                @trigger_error(sprintf('Using "%s" for the value of node "%s" of "%s" is deprecated since version 1.25 and will be removed in 2.0.', is_object($node) ? get_class($node) : null === $node ? 'null' : gettype($node), $name, get_class($this)), E_USER_DEPRECATED);
+                @trigger_error(sprintf('Using "%s" for the value of node "%s" of "%s" is deprecated since version 1.25 and will be removed in 2.0.', (is_object($node) ? get_class($node) : null) === $node ? 'null' : gettype($node), $name, get_class($this)), E_USER_DEPRECATED);
             }
         }
         $this->nodes = $nodes;
@@ -195,7 +195,7 @@ class Twig_Node implements Twig_NodeInterface
     public function setNode($name, $node = null)
     {
         if (!$node instanceof Twig_NodeInterface) {
-            @trigger_error(sprintf('Using "%s" for the value of node "%s" of "%s" is deprecated since version 1.25 and will be removed in 2.0.', is_object($node) ? get_class($node) : null === $node ? 'null' : gettype($node), $name, get_class($this)), E_USER_DEPRECATED);
+            @trigger_error(sprintf('Using "%s" for the value of node "%s" of "%s" is deprecated since version 1.25 and will be removed in 2.0.', (is_object($node) ? get_class($node) : null) === $node ? 'null' : gettype($node), $name, get_class($this)), E_USER_DEPRECATED);
         }
 
         $this->nodes[$name] = $node;

inc/lib/Twig/Template.php

@@ -579,7 +579,7 @@ abstract class Twig_Template implements Twig_TemplateInterface
 
         // object property
         if (self::METHOD_CALL !== $type && !$object instanceof self) { // Twig_Template does not have public properties, and we don't want to allow access to internal ones
-            if (isset($object->$item) || array_key_exists((string) $item, $object)) {
+            if (isset($object->$item) || property_exists($object, (string) $item)) {
                 if ($isDefinedTest) {
                     return true;
                 }