Replace node kind checks by InstanceOf checks

src/Executor/ReferenceExecutor.php

@@ -138,8 +138,8 @@ class ReferenceExecutor implements ExecutorImplementation
         $operation                    = null;
         $hasMultipleAssumedOperations = false;
         foreach ($documentNode->definitions as $definition) {
-            switch ($definition->kind) {
+            switch (true) {
-                case NodeKind::OPERATION_DEFINITION:
+                case $definition instanceof OperationDefinitionNode:
                     if (! $operationName && $operation) {
                         $hasMultipleAssumedOperations = true;
                     }
@@ -148,7 +148,7 @@ class ReferenceExecutor implements ExecutorImplementation
                         $operation = $definition;
                     }
                     break;
-                case NodeKind::FRAGMENT_DEFINITION:
+                case $definition instanceof FragmentDefinitionNode:
                     $fragments[$definition->name->value] = $definition;
                     break;
             }
@@ -334,8 +334,8 @@ class ReferenceExecutor implements ExecutorImplementation
     ) {
         $exeContext = $this->exeContext;
         foreach ($selectionSet->selections as $selection) {
-            switch ($selection->kind) {
+            switch (true) {
-                case NodeKind::FIELD:
+                case $selection instanceof FieldNode:
                     if (! $this->shouldIncludeNode($selection)) {
                         break;
                     }
@@ -345,7 +345,7 @@ class ReferenceExecutor implements ExecutorImplementation
                     }
                     $fields[$name][] = $selection;
                     break;
-                case NodeKind::INLINE_FRAGMENT:
+                case $selection instanceof InlineFragmentNode:
                     if (! $this->shouldIncludeNode($selection) ||
                         ! $this->doesFragmentConditionMatch($selection, $runtimeType)
                     ) {
@@ -358,7 +358,7 @@ class ReferenceExecutor implements ExecutorImplementation
                         $visitedFragmentNames
                     );
                     break;
-                case NodeKind::FRAGMENT_SPREAD:
+                case $selection instanceof FragmentSpreadNode:
                     $fragName = $selection->name->value;
                     if (! empty($visitedFragmentNames[$fragName]) || ! $this->shouldIncludeNode($selection)) {
                         break;

src/Experimental/Executor/Collector.php

@@ -64,7 +64,7 @@ class Collector
         foreach ($documentNode->definitions as $definitionNode) {
             /** @var DefinitionNode|Node $definitionNode */
 
-            if ($definitionNode->kind === NodeKind::OPERATION_DEFINITION) {
+            if ($definitionNode instanceof OperationDefinitionNode) {
                 /** @var OperationDefinitionNode $definitionNode */
                 if ($operationName === null && $this->operation !== null) {
                     $hasMultipleAssumedOperations = true;
@@ -74,7 +74,7 @@ class Collector
                 ) {
                     $this->operation = $definitionNode;
                 }
-            } elseif ($definitionNode->kind === NodeKind::FRAGMENT_DEFINITION) {
+            } elseif ($definitionNode instanceof FragmentDefinitionNode) {
                 /** @var FragmentDefinitionNode $definitionNode */
                 $this->fragments[$definitionNode->name->value] = $definitionNode;
             }
@@ -194,7 +194,7 @@ class Collector
                 }
             }
 
-            if ($selection->kind === NodeKind::FIELD) {
+            if ($selection instanceof FieldNode) {
                 /** @var FieldNode $selection */
 
                 $resultName = $selection->alias ? $selection->alias->value : $selection->name->value;
@@ -204,7 +204,7 @@ class Collector
                 }
 
                 $this->fields[$resultName][] = $selection;
-            } elseif ($selection->kind === NodeKind::FRAGMENT_SPREAD) {
+            } elseif ($selection instanceof FragmentSpreadNode) {
                 /** @var FragmentSpreadNode $selection */
 
                 $fragmentName = $selection->name->value;
@@ -245,7 +245,7 @@ class Collector
                 }
 
                 $this->doCollectFields($runtimeType, $fragmentDefinition->selectionSet);
-            } elseif ($selection->kind === NodeKind::INLINE_FRAGMENT) {
+            } elseif ($selection instanceof InlineFragmentNode) {
                 /** @var InlineFragmentNode $selection */
 
                 if ($selection->typeCondition !== null) {

src/Language/AST/ListTypeNode.php

@@ -9,6 +9,6 @@ class ListTypeNode extends Node implements TypeNode
     /** @var string */
     public $kind = NodeKind::LIST_TYPE;
 
-    /** @var Node */
+    /** @var TypeNode */
     public $type;
 }

src/Language/AST/NonNullTypeNode.php

@@ -9,6 +9,6 @@ class NonNullTypeNode extends Node implements TypeNode
     /** @var string */
     public $kind = NodeKind::NON_NULL_TYPE;
 
-    /** @var NameNode | ListTypeNode */
+    /** @var NamedTypeNode | ListTypeNode */
     public $type;
 }

src/Language/Printer.php

@@ -28,6 +28,7 @@ use GraphQL\Language\AST\IntValueNode;
 use GraphQL\Language\AST\ListTypeNode;
 use GraphQL\Language\AST\ListValueNode;
 use GraphQL\Language\AST\NamedTypeNode;
+use GraphQL\Language\AST\NameNode;
 use GraphQL\Language\AST\Node;
 use GraphQL\Language\AST\NodeKind;
 use GraphQL\Language\AST\NonNullTypeNode;
@@ -47,6 +48,7 @@ use GraphQL\Language\AST\StringValueNode;
 use GraphQL\Language\AST\UnionTypeDefinitionNode;
 use GraphQL\Language\AST\UnionTypeExtensionNode;
 use GraphQL\Language\AST\VariableDefinitionNode;
+use GraphQL\Language\AST\VariableNode;
 use GraphQL\Utils\Utils;
 use function count;
 use function implode;
@@ -97,11 +99,11 @@ class Printer
             $ast,
             [
                 'leave' => [
-                    NodeKind::NAME => static function (Node $node) {
+                    NodeKind::NAME => static function (NameNode $node) {
                         return '' . $node->value;
                     },
 
-                    NodeKind::VARIABLE => static function ($node) {
+                    NodeKind::VARIABLE => static function (VariableNode $node) {
                         return '$' . $node->name;
                     },
 

src/Utils/AST.php

@@ -322,7 +322,7 @@ class AST
      *
      * @api
      */
-    public static function valueFromAST($valueNode, InputType $type, ?array $variables = null)
+    public static function valueFromAST($valueNode, Type $type, ?array $variables = null)
     {
         $undefined = Utils::undefined();
 

src/Utils/ASTDefinitionBuilder.php

@@ -17,7 +17,6 @@ use GraphQL\Language\AST\InterfaceTypeDefinitionNode;
 use GraphQL\Language\AST\ListTypeNode;
 use GraphQL\Language\AST\NamedTypeNode;
 use GraphQL\Language\AST\Node;
-use GraphQL\Language\AST\NodeKind;
 use GraphQL\Language\AST\NonNullTypeNode;
 use GraphQL\Language\AST\ObjectTypeDefinitionNode;
 use GraphQL\Language\AST\ScalarTypeDefinitionNode;
@@ -244,23 +243,20 @@ class ASTDefinitionBuilder
      *
      * @throws Error
      */
-    private function makeSchemaDef($def)
+    private function makeSchemaDef(Node $def)
     {
-        if (! $def) {
+        switch (true) {
-            throw new Error('def must be defined.');
+            case $def instanceof ObjectTypeDefinitionNode:
-        }
-        switch ($def->kind) {
-            case NodeKind::OBJECT_TYPE_DEFINITION:
                 return $this->makeTypeDef($def);
-            case NodeKind::INTERFACE_TYPE_DEFINITION:
+            case $def instanceof InterfaceTypeDefinitionNode:
                 return $this->makeInterfaceDef($def);
-            case NodeKind::ENUM_TYPE_DEFINITION:
+            case $def instanceof EnumTypeDefinitionNode:
                 return $this->makeEnumDef($def);
-            case NodeKind::UNION_TYPE_DEFINITION:
+            case $def instanceof UnionTypeDefinitionNode:
                 return $this->makeUnionDef($def);
-            case NodeKind::SCALAR_TYPE_DEFINITION:
+            case $def instanceof ScalarTypeDefinitionNode:
                 return $this->makeScalarDef($def);
-            case NodeKind::INPUT_OBJECT_TYPE_DEFINITION:
+            case $def instanceof InputObjectTypeDefinitionNode:
                 return $this->makeInputObjectDef($def);
             default:
                 throw new Error(sprintf('Type kind of %s not supported.', $def->kind));
@@ -430,62 +426,48 @@ class ASTDefinitionBuilder
     }
 
     /**
-     * @param ObjectTypeDefinitionNode|InterfaceTypeDefinitionNode|EnumTypeExtensionNode|ScalarTypeDefinitionNode|InputObjectTypeDefinitionNode $def
      * @param mixed[] $config
      *
      * @return CustomScalarType|EnumType|InputObjectType|InterfaceType|ObjectType|UnionType
      *
      * @throws Error
      */
-    private function makeSchemaDefFromConfig($def, array $config)
+    private function makeSchemaDefFromConfig(Node $def, array $config)
     {
-        if (! $def) {
+        switch (true) {
-            throw new Error('def must be defined.');
+            case $def instanceof ObjectTypeDefinitionNode:
-        }
-        switch ($def->kind) {
-            case NodeKind::OBJECT_TYPE_DEFINITION:
                 return new ObjectType($config);
-            case NodeKind::INTERFACE_TYPE_DEFINITION:
+            case $def instanceof InterfaceTypeDefinitionNode:
                 return new InterfaceType($config);
-            case NodeKind::ENUM_TYPE_DEFINITION:
+            case $def instanceof EnumTypeDefinitionNode:
                 return new EnumType($config);
-            case NodeKind::UNION_TYPE_DEFINITION:
+            case $def instanceof UnionTypeDefinitionNode:
                 return new UnionType($config);
-            case NodeKind::SCALAR_TYPE_DEFINITION:
+            case $def instanceof ScalarTypeDefinitionNode:
                 return new CustomScalarType($config);
-            case NodeKind::INPUT_OBJECT_TYPE_DEFINITION:
+            case $def instanceof InputObjectTypeDefinitionNode:
                 return new InputObjectType($config);
             default:
                 throw new Error(sprintf('Type kind of %s not supported.', $def->kind));
         }
     }
 
-    /**
+    private function getNamedTypeNode(TypeNode $typeNode) : TypeNode
-     * @param TypeNode|ListTypeNode|NonNullTypeNode $typeNode
-     *
-     * @return TypeNode
-     */
-    private function getNamedTypeNode(TypeNode $typeNode)
     {
         $namedType = $typeNode;
-        while ($namedType->kind === NodeKind::LIST_TYPE || $namedType->kind === NodeKind::NON_NULL_TYPE) {
+        while ($namedType instanceof ListTypeNode || $namedType instanceof NonNullTypeNode) {
             $namedType = $namedType->type;
         }
 
         return $namedType;
     }
 
-    /**
+    private function buildWrappedType(Type $innerType, TypeNode $inputTypeNode) : Type
-     * @param TypeNode|ListTypeNode|NonNullTypeNode $inputTypeNode
-     *
-     * @return Type
-     */
-    private function buildWrappedType(Type $innerType, TypeNode $inputTypeNode)
     {
-        if ($inputTypeNode->kind === NodeKind::LIST_TYPE) {
+        if ($inputTypeNode instanceof ListTypeNode) {
             return Type::listOf($this->buildWrappedType($innerType, $inputTypeNode->type));
         }
-        if ($inputTypeNode->kind === NodeKind::NON_NULL_TYPE) {
+        if ($inputTypeNode instanceof NonNullTypeNode) {
             $wrappedType = $this->buildWrappedType($innerType, $inputTypeNode->type);
 
             return Type::nonNull(NonNull::assertNullableType($wrappedType));

src/Utils/BuildSchema.php

@@ -5,10 +5,16 @@ declare(strict_types=1);
 namespace GraphQL\Utils;
 
 use GraphQL\Error\Error;
+use GraphQL\Language\AST\DirectiveDefinitionNode;
 use GraphQL\Language\AST\DocumentNode;
+use GraphQL\Language\AST\EnumTypeDefinitionNode;
+use GraphQL\Language\AST\InputObjectTypeDefinitionNode;
+use GraphQL\Language\AST\InterfaceTypeDefinitionNode;
 use GraphQL\Language\AST\Node;
-use GraphQL\Language\AST\NodeKind;
+use GraphQL\Language\AST\ObjectTypeDefinitionNode;
+use GraphQL\Language\AST\ScalarTypeDefinitionNode;
 use GraphQL\Language\AST\SchemaDefinitionNode;
+use GraphQL\Language\AST\UnionTypeDefinitionNode;
 use GraphQL\Language\Parser;
 use GraphQL\Language\Source;
 use GraphQL\Type\Definition\Directive;
@@ -95,39 +101,38 @@ class BuildSchema
 
     public function buildSchema()
     {
-        /** @var SchemaDefinitionNode $schemaDef */
         $schemaDef     = null;
         $typeDefs      = [];
         $this->nodeMap = [];
         $directiveDefs = [];
-        foreach ($this->ast->definitions as $d) {
+        foreach ($this->ast->definitions as $definition) {
-            switch ($d->kind) {
+            switch (true) {
-                case NodeKind::SCHEMA_DEFINITION:
+                case $definition instanceof SchemaDefinitionNode:
-                    if ($schemaDef) {
+                    if ($schemaDef !== null) {
                         throw new Error('Must provide only one schema definition.');
                     }
-                    $schemaDef = $d;
+                    $schemaDef = $definition;
                     break;
-                case NodeKind::SCALAR_TYPE_DEFINITION:
+                case $definition instanceof ScalarTypeDefinitionNode:
-                case NodeKind::OBJECT_TYPE_DEFINITION:
+                case $definition instanceof ObjectTypeDefinitionNode:
-                case NodeKind::INTERFACE_TYPE_DEFINITION:
+                case $definition instanceof InterfaceTypeDefinitionNode:
-                case NodeKind::ENUM_TYPE_DEFINITION:
+                case $definition instanceof EnumTypeDefinitionNode:
-                case NodeKind::UNION_TYPE_DEFINITION:
+                case $definition instanceof UnionTypeDefinitionNode:
-                case NodeKind::INPUT_OBJECT_TYPE_DEFINITION:
+                case $definition instanceof InputObjectTypeDefinitionNode:
-                    $typeName = $d->name->value;
+                    $typeName = $definition->name->value;
                     if (! empty($this->nodeMap[$typeName])) {
                         throw new Error(sprintf('Type "%s" was defined more than once.', $typeName));
                     }
-                    $typeDefs[]               = $d;
+                    $typeDefs[]               = $definition;
-                    $this->nodeMap[$typeName] = $d;
+                    $this->nodeMap[$typeName] = $definition;
                     break;
-                case NodeKind::DIRECTIVE_DEFINITION:
+                case $definition instanceof DirectiveDefinitionNode:
-                    $directiveDefs[] = $d;
+                    $directiveDefs[] = $definition;
                     break;
             }
         }
 
-        $operationTypes = $schemaDef
+        $operationTypes = $schemaDef !== null
             ? $this->getOperationTypes($schemaDef)
             : [
                 'query'        => isset($this->nodeMap['Query']) ? 'Query' : null,

src/Utils/SchemaExtender.php

@@ -7,13 +7,16 @@ namespace GraphQL\Utils;
 use GraphQL\Error\Error;
 use GraphQL\Language\AST\DirectiveDefinitionNode;
 use GraphQL\Language\AST\DocumentNode;
+use GraphQL\Language\AST\EnumTypeExtensionNode;
+use GraphQL\Language\AST\InputObjectTypeExtensionNode;
+use GraphQL\Language\AST\InterfaceTypeExtensionNode;
 use GraphQL\Language\AST\Node;
-use GraphQL\Language\AST\NodeKind;
 use GraphQL\Language\AST\ObjectTypeExtensionNode;
 use GraphQL\Language\AST\SchemaDefinitionNode;
 use GraphQL\Language\AST\SchemaTypeExtensionNode;
 use GraphQL\Language\AST\TypeDefinitionNode;
 use GraphQL\Language\AST\TypeExtensionNode;
+use GraphQL\Language\AST\UnionTypeExtensionNode;
 use GraphQL\Type\Definition\CustomScalarType;
 use GraphQL\Type\Definition\Directive;
 use GraphQL\Type\Definition\EnumType;
@@ -74,8 +77,8 @@ class SchemaExtender
      */
     protected static function checkExtensionNode(Type $type, Node $node) : void
     {
-        switch ($node->kind) {
+        switch (true) {
-            case NodeKind::OBJECT_TYPE_EXTENSION:
+            case $node instanceof ObjectTypeExtensionNode:
                 if (! ($type instanceof ObjectType)) {
                     throw new Error(
                         'Cannot extend non-object type "' . $type->name . '".',
@@ -83,7 +86,7 @@ class SchemaExtender
                     );
                 }
                 break;
-            case NodeKind::INTERFACE_TYPE_EXTENSION:
+            case $node instanceof InterfaceTypeExtensionNode:
                 if (! ($type instanceof InterfaceType)) {
                     throw new Error(
                         'Cannot extend non-interface type "' . $type->name . '".',
@@ -91,7 +94,7 @@ class SchemaExtender
                     );
                 }
                 break;
-            case NodeKind::ENUM_TYPE_EXTENSION:
+            case $node instanceof EnumTypeExtensionNode:
                 if (! ($type instanceof EnumType)) {
                     throw new Error(
                         'Cannot extend non-enum type "' . $type->name . '".',
@@ -99,7 +102,7 @@ class SchemaExtender
                     );
                 }
                 break;
-            case NodeKind::UNION_TYPE_EXTENSION:
+            case $node instanceof UnionTypeExtensionNode:
                 if (! ($type instanceof UnionType)) {
                     throw new Error(
                         'Cannot extend non-union type "' . $type->name . '".',
@@ -107,7 +110,7 @@ class SchemaExtender
                     );
                 }
                 break;
-            case NodeKind::INPUT_OBJECT_TYPE_EXTENSION:
+            case $node instanceof InputObjectTypeExtensionNode:
                 if (! ($type instanceof InputObjectType)) {
                     throw new Error(
                         'Cannot extend non-input object type "' . $type->name . '".',

src/Utils/TypeInfo.php

@@ -6,12 +6,21 @@ namespace GraphQL\Utils;
 
 use GraphQL\Error\InvariantViolation;
 use GraphQL\Error\Warning;
+use GraphQL\Language\AST\ArgumentNode;
+use GraphQL\Language\AST\DirectiveNode;
+use GraphQL\Language\AST\EnumValueNode;
 use GraphQL\Language\AST\FieldNode;
+use GraphQL\Language\AST\FragmentDefinitionNode;
+use GraphQL\Language\AST\InlineFragmentNode;
 use GraphQL\Language\AST\ListTypeNode;
+use GraphQL\Language\AST\ListValueNode;
 use GraphQL\Language\AST\NamedTypeNode;
 use GraphQL\Language\AST\Node;
-use GraphQL\Language\AST\NodeKind;
 use GraphQL\Language\AST\NonNullTypeNode;
+use GraphQL\Language\AST\ObjectFieldNode;
+use GraphQL\Language\AST\OperationDefinitionNode;
+use GraphQL\Language\AST\SelectionSetNode;
+use GraphQL\Language\AST\VariableDefinitionNode;
 use GraphQL\Type\Definition\CompositeType;
 use GraphQL\Type\Definition\Directive;
 use GraphQL\Type\Definition\EnumType;
@@ -255,13 +264,13 @@ class TypeInfo
         // any assumptions of a valid schema to ensure runtime types are properly
         // checked before continuing since TypeInfo is used as part of validation
         // which occurs before guarantees of schema and document validity.
-        switch ($node->kind) {
+        switch (true) {
-            case NodeKind::SELECTION_SET:
+            case $node instanceof SelectionSetNode:
                 $namedType               = Type::getNamedType($this->getType());
                 $this->parentTypeStack[] = Type::isCompositeType($namedType) ? $namedType : null;
                 break;
 
-            case NodeKind::FIELD:
+            case $node instanceof FieldNode:
                 $parentType = $this->getParentType();
                 $fieldDef   = null;
                 if ($parentType) {
@@ -275,11 +284,11 @@ class TypeInfo
                 $this->typeStack[]     = Type::isOutputType($fieldType) ? $fieldType : null;
                 break;
 
-            case NodeKind::DIRECTIVE:
+            case $node instanceof DirectiveNode:
                 $this->directive = $schema->getDirective($node->name->value);
                 break;
 
-            case NodeKind::OPERATION_DEFINITION:
+            case $node instanceof OperationDefinitionNode:
                 $type = null;
                 if ($node->operation === 'query') {
                     $type = $schema->getQueryType();
@@ -291,8 +300,8 @@ class TypeInfo
                 $this->typeStack[] = Type::isOutputType($type) ? $type : null;
                 break;
 
-            case NodeKind::INLINE_FRAGMENT:
+            case $node instanceof InlineFragmentNode:
-            case NodeKind::FRAGMENT_DEFINITION:
+            case $node instanceof FragmentDefinitionNode:
                 $typeConditionNode = $node->typeCondition;
                 $outputType        = $typeConditionNode ? self::typeFromAST(
                     $schema,
@@ -301,12 +310,12 @@ class TypeInfo
                 $this->typeStack[] = Type::isOutputType($outputType) ? $outputType : null;
                 break;
 
-            case NodeKind::VARIABLE_DEFINITION:
+            case $node instanceof VariableDefinitionNode:
                 $inputType              = self::typeFromAST($schema, $node->type);
                 $this->inputTypeStack[] = Type::isInputType($inputType) ? $inputType : null; // push
                 break;
 
-            case NodeKind::ARGUMENT:
+            case $node instanceof ArgumentNode:
                 $fieldOrDirective = $this->getDirective() ?: $this->getFieldDef();
                 $argDef           = $argType = null;
                 if ($fieldOrDirective) {
@@ -324,7 +333,7 @@ class TypeInfo
                 $this->inputTypeStack[] = Type::isInputType($argType) ? $argType : null;
                 break;
 
-            case NodeKind::LST:
+            case $node instanceof ListValueNode:
                 $listType               = Type::getNullableType($this->getInputType());
                 $itemType               = $listType instanceof ListOfType
                     ? $listType->getWrappedType()
@@ -332,7 +341,7 @@ class TypeInfo
                 $this->inputTypeStack[] = Type::isInputType($itemType) ? $itemType : null;
                 break;
 
-            case NodeKind::OBJECT_FIELD:
+            case $node instanceof ObjectFieldNode:
                 $objectType     = Type::getNamedType($this->getInputType());
                 $fieldType      = null;
                 $inputFieldType = null;
@@ -344,7 +353,7 @@ class TypeInfo
                 $this->inputTypeStack[] = Type::isInputType($inputFieldType) ? $inputFieldType : null;
                 break;
 
-            case NodeKind::ENUM:
+            case $node instanceof EnumValueNode:
                 $enumType  = Type::getNamedType($this->getInputType());
                 $enumValue = null;
                 if ($enumType instanceof EnumType) {
@@ -458,37 +467,37 @@ class TypeInfo
 
     public function leave(Node $node)
     {
-        switch ($node->kind) {
+        switch (true) {
-            case NodeKind::SELECTION_SET:
+            case $node instanceof SelectionSetNode:
                 array_pop($this->parentTypeStack);
                 break;
 
-            case NodeKind::FIELD:
+            case $node instanceof FieldNode:
                 array_pop($this->fieldDefStack);
                 array_pop($this->typeStack);
                 break;
 
-            case NodeKind::DIRECTIVE:
+            case $node instanceof DirectiveNode:
                 $this->directive = null;
                 break;
 
-            case NodeKind::OPERATION_DEFINITION:
+            case $node instanceof OperationDefinitionNode:
-            case NodeKind::INLINE_FRAGMENT:
+            case $node instanceof InlineFragmentNode:
-            case NodeKind::FRAGMENT_DEFINITION:
+            case $node instanceof FragmentDefinitionNode:
                 array_pop($this->typeStack);
                 break;
-            case NodeKind::VARIABLE_DEFINITION:
+            case $node instanceof VariableDefinitionNode:
                 array_pop($this->inputTypeStack);
                 break;
-            case NodeKind::ARGUMENT:
+            case $node instanceof ArgumentNode:
                 $this->argument = null;
                 array_pop($this->inputTypeStack);
                 break;
-            case NodeKind::LST:
+            case $node instanceof ListValueNode:
-            case NodeKind::OBJECT_FIELD:
+            case $node instanceof ObjectFieldNode:
                 array_pop($this->inputTypeStack);
                 break;
-            case NodeKind::ENUM:
+            case $node instanceof EnumValueNode:
                 $this->enumValue = null;
                 break;
         }

src/Validator/Rules/KnownArgumentNames.php

@@ -6,6 +6,8 @@ namespace GraphQL\Validator\Rules;
 
 use GraphQL\Error\Error;
 use GraphQL\Language\AST\ArgumentNode;
+use GraphQL\Language\AST\DirectiveNode;
+use GraphQL\Language\AST\FieldNode;
 use GraphQL\Language\AST\Node;
 use GraphQL\Language\AST\NodeKind;
 use GraphQL\Language\AST\NodeList;
@@ -34,7 +36,7 @@ class KnownArgumentNames extends ValidationRule
                 }
 
                 $argumentOf = $ancestors[count($ancestors) - 1];
-                if ($argumentOf->kind === NodeKind::FIELD) {
+                if ($argumentOf instanceof FieldNode) {
                     $fieldDef   = $context->getFieldDef();
                     $parentType = $context->getParentType();
                     if ($fieldDef && $parentType) {
@@ -56,7 +58,7 @@ class KnownArgumentNames extends ValidationRule
                             [$node]
                         ));
                     }
-                } elseif ($argumentOf->kind === NodeKind::DIRECTIVE) {
+                } elseif ($argumentOf instanceof DirectiveNode) {
                     $directive = $context->getDirective();
                     if ($directive) {
                         $context->reportError(new Error(

src/Validator/Rules/KnownDirectives.php

@@ -7,10 +7,31 @@ namespace GraphQL\Validator\Rules;
 use GraphQL\Error\Error;
 use GraphQL\Language\AST\DirectiveDefinitionNode;
 use GraphQL\Language\AST\DirectiveNode;
+use GraphQL\Language\AST\EnumTypeDefinitionNode;
+use GraphQL\Language\AST\EnumTypeExtensionNode;
+use GraphQL\Language\AST\EnumValueDefinitionNode;
+use GraphQL\Language\AST\FieldDefinitionNode;
+use GraphQL\Language\AST\FieldNode;
+use GraphQL\Language\AST\FragmentDefinitionNode;
+use GraphQL\Language\AST\FragmentSpreadNode;
+use GraphQL\Language\AST\InlineFragmentNode;
 use GraphQL\Language\AST\InputObjectTypeDefinitionNode;
+use GraphQL\Language\AST\InputObjectTypeExtensionNode;
+use GraphQL\Language\AST\InputValueDefinitionNode;
+use GraphQL\Language\AST\InterfaceTypeDefinitionNode;
+use GraphQL\Language\AST\InterfaceTypeExtensionNode;
 use GraphQL\Language\AST\Node;
 use GraphQL\Language\AST\NodeKind;
 use GraphQL\Language\AST\NodeList;
+use GraphQL\Language\AST\ObjectTypeDefinitionNode;
+use GraphQL\Language\AST\ObjectTypeExtensionNode;
+use GraphQL\Language\AST\OperationDefinitionNode;
+use GraphQL\Language\AST\ScalarTypeDefinitionNode;
+use GraphQL\Language\AST\ScalarTypeExtensionNode;
+use GraphQL\Language\AST\SchemaDefinitionNode;
+use GraphQL\Language\AST\SchemaTypeExtensionNode;
+use GraphQL\Language\AST\UnionTypeDefinitionNode;
+use GraphQL\Language\AST\UnionTypeExtensionNode;
 use GraphQL\Language\DirectiveLocation;
 use GraphQL\Validator\ValidationContext;
 use function array_map;
@@ -96,8 +117,8 @@ class KnownDirectives extends ValidationRule
     private function getDirectiveLocationForASTPath(array $ancestors)
     {
         $appliedTo = $ancestors[count($ancestors) - 1];
-        switch ($appliedTo->kind) {
+        switch (true) {
-            case NodeKind::OPERATION_DEFINITION:
+            case $appliedTo instanceof OperationDefinitionNode:
                 switch ($appliedTo->operation) {
                     case 'query':
                         return DirectiveLocation::QUERY;
@@ -107,40 +128,40 @@ class KnownDirectives extends ValidationRule
                         return DirectiveLocation::SUBSCRIPTION;
                 }
                 break;
-            case NodeKind::FIELD:
+            case $appliedTo instanceof FieldNode:
                 return DirectiveLocation::FIELD;
-            case NodeKind::FRAGMENT_SPREAD:
+            case $appliedTo instanceof FragmentSpreadNode:
                 return DirectiveLocation::FRAGMENT_SPREAD;
-            case NodeKind::INLINE_FRAGMENT:
+            case $appliedTo instanceof InlineFragmentNode:
                 return DirectiveLocation::INLINE_FRAGMENT;
-            case NodeKind::FRAGMENT_DEFINITION:
+            case $appliedTo instanceof FragmentDefinitionNode:
                 return DirectiveLocation::FRAGMENT_DEFINITION;
-            case NodeKind::SCHEMA_DEFINITION:
+            case $appliedTo instanceof SchemaDefinitionNode:
-            case NodeKind::SCHEMA_EXTENSION:
+            case $appliedTo instanceof SchemaTypeExtensionNode:
                 return DirectiveLocation::SCHEMA;
-            case NodeKind::SCALAR_TYPE_DEFINITION:
+            case $appliedTo instanceof ScalarTypeDefinitionNode:
-            case NodeKind::SCALAR_TYPE_EXTENSION:
+            case $appliedTo instanceof ScalarTypeExtensionNode:
                 return DirectiveLocation::SCALAR;
-            case NodeKind::OBJECT_TYPE_DEFINITION:
+            case $appliedTo instanceof ObjectTypeDefinitionNode:
-            case NodeKind::OBJECT_TYPE_EXTENSION:
+            case $appliedTo instanceof ObjectTypeExtensionNode:
                 return DirectiveLocation::OBJECT;
-            case NodeKind::FIELD_DEFINITION:
+            case $appliedTo instanceof FieldDefinitionNode:
                 return DirectiveLocation::FIELD_DEFINITION;
-            case NodeKind::INTERFACE_TYPE_DEFINITION:
+            case $appliedTo instanceof InterfaceTypeDefinitionNode:
-            case NodeKind::INTERFACE_TYPE_EXTENSION:
+            case $appliedTo instanceof InterfaceTypeExtensionNode:
                 return DirectiveLocation::IFACE;
-            case NodeKind::UNION_TYPE_DEFINITION:
+            case $appliedTo instanceof UnionTypeDefinitionNode:
-            case NodeKind::UNION_TYPE_EXTENSION:
+            case $appliedTo instanceof UnionTypeExtensionNode:
                 return DirectiveLocation::UNION;
-            case NodeKind::ENUM_TYPE_DEFINITION:
+            case $appliedTo instanceof EnumTypeDefinitionNode:
-            case NodeKind::ENUM_TYPE_EXTENSION:
+            case $appliedTo instanceof EnumTypeExtensionNode:
                 return DirectiveLocation::ENUM;
-            case NodeKind::ENUM_VALUE_DEFINITION:
+            case $appliedTo instanceof EnumValueDefinitionNode:
                 return DirectiveLocation::ENUM_VALUE;
-            case NodeKind::INPUT_OBJECT_TYPE_DEFINITION:
+            case $appliedTo instanceof InputObjectTypeDefinitionNode:
-            case NodeKind::INPUT_OBJECT_TYPE_EXTENSION:
+            case $appliedTo instanceof InputObjectTypeExtensionNode:
                 return DirectiveLocation::INPUT_OBJECT;
-            case NodeKind::INPUT_VALUE_DEFINITION:
+            case $appliedTo instanceof InputValueDefinitionNode:
                 $parentNode = $ancestors[count($ancestors) - 3];
 
                 return $parentNode instanceof InputObjectTypeDefinitionNode

src/Validator/Rules/LoneAnonymousOperation.php

@@ -30,7 +30,7 @@ class LoneAnonymousOperation extends ValidationRule
                 $tmp = Utils::filter(
                     $node->definitions,
                     static function (Node $definition) {
-                        return $definition->kind === NodeKind::OPERATION_DEFINITION;
+                        return $definition instanceof OperationDefinitionNode;
                     }
                 );
 

src/Validator/Rules/QueryComplexity.php

@@ -110,9 +110,8 @@ class QueryComplexity extends QuerySecurityRule
 
     private function nodeComplexity(Node $node, $complexity = 0)
     {
-        switch ($node->kind) {
+        switch (true) {
-            case NodeKind::FIELD:
+            case $node instanceof FieldNode:
-                /** @var FieldNode $node */
                 // default values
                 $args         = [];
                 $complexityFn = FieldDefinition::DEFAULT_COMPLEXITY_FN;
@@ -143,16 +142,14 @@ class QueryComplexity extends QuerySecurityRule
                 $complexity += call_user_func_array($complexityFn, [$childrenComplexity, $args]);
                 break;
 
-            case NodeKind::INLINE_FRAGMENT:
+            case $node instanceof InlineFragmentNode:
-                /** @var InlineFragmentNode $node */
                 // node has children?
                 if (isset($node->selectionSet)) {
                     $complexity = $this->fieldComplexity($node, $complexity);
                 }
                 break;
 
-            case NodeKind::FRAGMENT_SPREAD:
+            case $node instanceof FragmentSpreadNode:
-                /** @var FragmentSpreadNode $node */
                 $fragment = $this->getFragment($node);
 
                 if ($fragment !== null) {

src/Validator/Rules/QueryDepth.php

@@ -5,6 +5,9 @@ declare(strict_types=1);
 namespace GraphQL\Validator\Rules;
 
 use GraphQL\Error\Error;
+use GraphQL\Language\AST\FieldNode;
+use GraphQL\Language\AST\FragmentSpreadNode;
+use GraphQL\Language\AST\InlineFragmentNode;
 use GraphQL\Language\AST\Node;
 use GraphQL\Language\AST\NodeKind;
 use GraphQL\Language\AST\OperationDefinitionNode;
@@ -57,9 +60,8 @@ class QueryDepth extends QuerySecurityRule
 
     private function nodeDepth(Node $node, $depth = 0, $maxDepth = 0)
     {
-        switch ($node->kind) {
+        switch (true) {
-            case NodeKind::FIELD:
+            case $node instanceof FieldNode:
-                /** @var FieldNode $node */
                 // node has children?
                 if ($node->selectionSet !== null) {
                     // update maxDepth if needed
@@ -70,16 +72,14 @@ class QueryDepth extends QuerySecurityRule
                 }
                 break;
 
-            case NodeKind::INLINE_FRAGMENT:
+            case $node instanceof InlineFragmentNode:
-                /** @var InlineFragmentNode $node */
                 // node has children?
                 if ($node->selectionSet !== null) {
                     $maxDepth = $this->fieldDepth($node, $depth, $maxDepth);
                 }
                 break;
 
-            case NodeKind::FRAGMENT_SPREAD:
+            case $node instanceof FragmentSpreadNode:
-                /** @var FragmentSpreadNode $node */
                 $fragment = $this->getFragment($node);
 
                 if ($fragment !== null) {

src/Validator/Rules/QuerySecurityRule.php

@@ -9,7 +9,6 @@ use GraphQL\Language\AST\FieldNode;
 use GraphQL\Language\AST\FragmentDefinitionNode;
 use GraphQL\Language\AST\FragmentSpreadNode;
 use GraphQL\Language\AST\InlineFragmentNode;
-use GraphQL\Language\AST\NodeKind;
 use GraphQL\Language\AST\SelectionSetNode;
 use GraphQL\Type\Definition\Type;
 use GraphQL\Type\Introspection;
@@ -114,8 +113,8 @@ abstract class QuerySecurityRule extends ValidationRule
         $_astAndDefs           = $astAndDefs ?: new ArrayObject();
 
         foreach ($selectionSet->selections as $selection) {
-            switch ($selection->kind) {
+            switch (true) {
-                case NodeKind::FIELD:
+                case $selection instanceof FieldNode:
                     /** @var FieldNode $selection */
                     $fieldName = $selection->name->value;
                     $fieldDef  = null;
@@ -142,7 +141,7 @@ abstract class QuerySecurityRule extends ValidationRule
                     // create field context
                     $_astAndDefs[$responseName][] = [$selection, $fieldDef];
                     break;
-                case NodeKind::INLINE_FRAGMENT:
+                case $selection instanceof InlineFragmentNode:
                     /** @var InlineFragmentNode $selection */
                     $_astAndDefs = $this->collectFieldASTsAndDefs(
                         $context,
@@ -152,7 +151,7 @@ abstract class QuerySecurityRule extends ValidationRule
                         $_astAndDefs
                     );
                     break;
-                case NodeKind::FRAGMENT_SPREAD:
+                case $selection instanceof FragmentSpreadNode:
                     /** @var FragmentSpreadNode $selection */
                     $fragName = $selection->name->value;
 

src/Validator/ValidationContext.php

@@ -199,7 +199,7 @@ class ValidationContext
 
                 for ($i = 0, $selectionCount = count($set->selections); $i < $selectionCount; $i++) {
                     $selection = $set->selections[$i];
-                    if ($selection->kind === NodeKind::FRAGMENT_SPREAD) {
+                    if ($selection instanceof FragmentSpreadNode) {
                         $spreads[] = $selection;
                     } elseif ($selection->selectionSet) {
                         $setsToVisit[] = $selection->selectionSet;
@@ -223,7 +223,7 @@ class ValidationContext
         if (! $fragments) {
             $fragments = [];
             foreach ($this->getDocument()->definitions as $statement) {
-                if ($statement->kind !== NodeKind::FRAGMENT_DEFINITION) {
+                if (! ($statement instanceof FragmentDefinitionNode)) {
                     continue;
                 }
 

tests/Experimental/Executor/CollectorTest.php

@@ -362,7 +362,7 @@ class CollectorTest extends TestCase
             $operationName = null;
             foreach ($documentNode->definitions as $definitionNode) {
                 /** @var Node $definitionNode */
-                if ($definitionNode->kind === NodeKind::OPERATION_DEFINITION) {
+                if ($definitionNode instanceof OperationDefinitionNode) {
                     /** @var OperationDefinitionNode $definitionNode */
                     self::assertNotNull($definitionNode->name);
                     $operationName = $definitionNode->name->value;

tests/Language/VisitorTest.php

@@ -384,7 +384,7 @@ class VisitorTest extends ValidatorTestCase
                     $this->checkVisitorFnArgs($ast, func_get_args());
                     $visited[] = ['leave', $node->kind, $node->value ?? null];
 
-                    if ($node->kind === NodeKind::NAME && $node->value === 'x') {
+                    if ($node instanceof NameNode && $node->value === 'x') {
                         return Visitor::stop();
                     }
                 },