Add isSpecialClassName() method to Identifier and Name

lib/PhpParser/NameContext.php

@@ -100,8 +100,7 @@ class NameContext {
      */
     public function getResolvedName(Name $name, int $type) {
         // don't resolve special class names
-        if ($type === Stmt\Use_::TYPE_NORMAL
-                && in_array($name->toLowerString(), ['self', 'parent', 'static'])) {
+        if ($type === Stmt\Use_::TYPE_NORMAL && $name->isSpecialClassName()) {
             if (!$name->isUnqualified()) {
                 $this->errorHandler->handleError(new Error(
                     sprintf("'\\%s' is an invalid class name", $name->toString()),

lib/PhpParser/Node/Identifier.php

@@ -12,6 +12,12 @@ class Identifier extends NodeAbstract
     /** @var string Identifier as string */
     public $name;
 
+    private static $specialClassNames = [
+        'self'   => true,
+        'parent' => true,
+        'static' => true,
+    ];
+
     /**
      * Constructs an identifier node.
      *
@@ -36,6 +42,15 @@ class Identifier extends NodeAbstract
         return strtolower($this->name);
     }
 
+    /**
+     * Checks whether the identifier is a special class name (self, parent or static).
+     *
+     * @return bool Whether identifier is a special class name
+     */
+    public function isSpecialClassName() : bool {
+        return isset(self::$specialClassNames[strtolower($this->name)]);
+    }
+
     /**
      * Get identifier as string.
      *

lib/PhpParser/Node/Name.php

@@ -11,6 +11,12 @@ class Name extends NodeAbstract
      */
     public $parts;
 
+    private static $specialClassNames = [
+        'self'   => true,
+        'parent' => true,
+        'static' => true,
+    ];
+
     /**
      * Constructs a name node.
      *
@@ -110,6 +116,16 @@ class Name extends NodeAbstract
         return strtolower(implode('\\', $this->parts));
     }
 
+    /**
+     * Checks whether the identifier is a special class name (self, parent or static).
+     *
+     * @return bool Whether identifier is a special class name
+     */
+    public function isSpecialClassName() : bool {
+        return count($this->parts) === 1
+            && isset(self::$specialClassNames[strtolower($this->parts[0])]);
+    }
+
     /**
      * Returns a string representation of the name by imploding the namespace parts with the
      * namespace separator.

lib/PhpParser/Node/Stmt/Class_.php

@@ -23,12 +23,6 @@ class Class_ extends ClassLike
     /** @var Node\Name[] Names of implemented interfaces */
     public $implements;
 
-    protected static $specialNames = [
-        'self'   => true,
-        'parent' => true,
-        'static' => true,
-    ];
-
     /**
      * Constructs a class node.
      *

lib/PhpParser/ParserAbstract.php

@@ -654,12 +654,6 @@ abstract class ParserAbstract implements Parser
         return new Node\Identifier($lowerName, $name->getAttributes());
     }
 
-    protected static $specialNames = [
-        'self'   => true,
-        'parent' => true,
-        'static' => true,
-    ];
-
     /**
      * Get combined start and end attributes at a stack location
      *
@@ -730,7 +724,7 @@ abstract class ParserAbstract implements Parser
     }
 
     protected function checkNamespace(Namespace_ $node) {
-        if ($node->name && isset(self::$specialNames[$node->name->toLowerString()])) {
+        if ($node->name && $node->name->isSpecialClassName()) {
             $this->emitError(new Error(
                 sprintf('Cannot use \'%s\' as namespace name', $node->name),
                 $node->name->getAttributes()
@@ -749,14 +743,14 @@ abstract class ParserAbstract implements Parser
     }
 
     protected function checkClass(Class_ $node, $namePos) {
-        if (null !== $node->name && isset(self::$specialNames[$node->name->toLowerString()])) {
+        if (null !== $node->name && $node->name->isSpecialClassName()) {
             $this->emitError(new Error(
                 sprintf('Cannot use \'%s\' as class name as it is reserved', $node->name),
                 $this->getAttributesAt($namePos)
             ));
         }
 
-        if ($node->extends && isset(self::$specialNames[$node->extends->toLowerString()])) {
+        if ($node->extends && $node->extends->isSpecialClassName()) {
             $this->emitError(new Error(
                 sprintf('Cannot use \'%s\' as class name as it is reserved', $node->extends),
                 $node->extends->getAttributes()
@@ -764,7 +758,7 @@ abstract class ParserAbstract implements Parser
         }
 
         foreach ($node->implements as $interface) {
-            if (isset(self::$specialNames[$interface->toLowerString()])) {
+            if ($interface->isSpecialClassName()) {
                 $this->emitError(new Error(
                     sprintf('Cannot use \'%s\' as interface name as it is reserved', $interface),
                     $interface->getAttributes()
@@ -774,7 +768,7 @@ abstract class ParserAbstract implements Parser
     }
 
     protected function checkInterface(Interface_ $node, $namePos) {
-        if (null !== $node->name && isset(self::$specialNames[$node->name->toLowerString()])) {
+        if (null !== $node->name && $node->name->isSpecialClassName()) {
             $this->emitError(new Error(
                 sprintf('Cannot use \'%s\' as class name as it is reserved', $node->name),
                 $this->getAttributesAt($namePos)
@@ -782,7 +776,7 @@ abstract class ParserAbstract implements Parser
         }
 
         foreach ($node->extends as $interface) {
-            if (isset(self::$specialNames[$interface->toLowerString()])) {
+            if ($interface->isSpecialClassName()) {
                 $this->emitError(new Error(
                     sprintf('Cannot use \'%s\' as interface name as it is reserved', $interface),
                     $interface->getAttributes()
@@ -844,9 +838,7 @@ abstract class ParserAbstract implements Parser
     }
 
     protected function checkUseUse(UseUse $node, $namePos) {
-        if ($node->alias &&
-            ('self' === $node->alias->toLowerString() || 'parent' === $node->alias->toLowerString())
-        ) {
+        if ($node->alias && $node->alias->isSpecialClassName()) {
             $this->emitError(new Error(
                 sprintf(
                     'Cannot use %s as %s because \'%2$s\' is a special class name',