WooCommerce Code Reference

Visitor
in package

Utility for efficient AST traversal and modification.

visit() will walk through an AST using a depth first traversal, calling the visitor's enter function at each node in the traversal, and calling the leave function after visiting that node and all of its child nodes.

By returning different values from the enter and leave functions, the behavior of the visitor can be altered.

  • no return (void) or return null: no action
  • Visitor::skipNode(): skips over the subtree at the current node of the AST
  • Visitor::stop(): stop the Visitor completely
  • Visitor::removeNode(): remove the current node
  • return any other value: replace this node with the returned value

When using visit() to edit an AST, the original AST will not be modified, and a new version of the AST with the changes applied will be returned from the visit function.

$editedAST = Visitor::visit($ast, [
    'enter' => function (Node $node, $key, $parent, array $path, array $ancestors) {
        // ...
    },
    'leave' => function (Node $node, $key, $parent, array $path, array $ancestors) {
        // ...
    }
]);

Alternatively to providing enter and leave functions, a visitor can instead provide functions named the same as the kinds of AST nodes, or enter/leave visitors at a named key, leading to four permutations of visitor API:

  1. Named visitors triggered when entering a node a specific kind.

    Visitor::visit($ast, [
    NodeKind::OBJECT_TYPE_DEFINITION => function (ObjectTypeDefinitionNode $node) {
        // enter the "ObjectTypeDefinition" node
    }
]);

  2. Named visitors that trigger upon entering and leaving a node of a specific kind.

    Visitor::visit($ast, [
    NodeKind::OBJECT_TYPE_DEFINITION => [
        'enter' => function (ObjectTypeDefinitionNode $node) {
            // enter the "ObjectTypeDefinition" node
        },
        'leave' => function (ObjectTypeDefinitionNode $node) {
            // leave the "ObjectTypeDefinition" node
        }
    ]
]);

  3. Generic visitors that trigger upon entering and leaving any node.

    Visitor::visit($ast, [
    'enter' => function (Node $node) {
        // enter any node
    },
    'leave' => function (Node $node) {
        // leave any node
    }
]);

  4. Parallel visitors for entering and leaving nodes of a specific kind.

    Visitor::visit($ast, [
    'enter' => [
        NodeKind::OBJECT_TYPE_DEFINITION => function (ObjectTypeDefinitionNode $node) {
            // enter the "ObjectTypeDefinition" node
        }
    ],
    'leave' => [
        NodeKind::OBJECT_TYPE_DEFINITION => function (ObjectTypeDefinitionNode $node) {
            // leave the "ObjectTypeDefinition" node
        }
    ]
]);
Tags
phpstan-type

NodeVisitor callable(Node): (VisitorOperation|Node|NodeList|null|false|void)

phpstan-type

VisitorArray array<string, NodeVisitor>|array<string, array<string, NodeVisitor>>

see
VisitorTest

Table of Contents

VISITOR_KEYS  = [AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::NAME => [], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::DOCUMENT => ['definitions'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::OPERATION_DEFINITION => ['name', 'variableDefinitions', 'directives', 'selectionSet'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::VARIABLE_DEFINITION => ['variable', 'type', 'defaultValue', 'directives'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::VARIABLE => ['name'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::SELECTION_SET => ['selections'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::FIELD => ['alias', 'name', 'arguments', 'directives', 'selectionSet'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::ARGUMENT => ['name', 'value'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::FRAGMENT_SPREAD => ['name', 'directives'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::INLINE_FRAGMENT => ['typeCondition', 'directives', 'selectionSet'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::FRAGMENT_DEFINITION => [ 'name', // Note: fragment variable definitions are experimental and may be changed // or removed in the future. 'variableDefinitions', 'typeCondition', 'directives', 'selectionSet', ], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::INT => [], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::FLOAT => [], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::STRING => [], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::BOOLEAN => [], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::NULL => [], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::ENUM => [], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::LST => ['values'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::OBJECT => ['fields'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::OBJECT_FIELD => ['name', 'value'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::DIRECTIVE => ['name', 'arguments'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::NAMED_TYPE => ['name'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::LIST_TYPE => ['type'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::NON_NULL_TYPE => ['type'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::SCHEMA_DEFINITION => ['description', 'directives', 'operationTypes'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::OPERATION_TYPE_DEFINITION => ['type'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::SCALAR_TYPE_DEFINITION => ['description', 'name', 'directives'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::OBJECT_TYPE_DEFINITION => ['description', 'name', 'interfaces', 'directives', 'fields'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::FIELD_DEFINITION => ['description', 'name', 'arguments', 'type', 'directives'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::INPUT_VALUE_DEFINITION => ['description', 'name', 'type', 'defaultValue', 'directives'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::INTERFACE_TYPE_DEFINITION => ['description', 'name', 'interfaces', 'directives', 'fields'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::UNION_TYPE_DEFINITION => ['description', 'name', 'directives', 'types'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::ENUM_TYPE_DEFINITION => ['description', 'name', 'directives', 'values'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::ENUM_VALUE_DEFINITION => ['description', 'name', 'directives'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::INPUT_OBJECT_TYPE_DEFINITION => ['description', 'name', 'directives', 'fields'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::SCALAR_TYPE_EXTENSION => ['name', 'directives'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::OBJECT_TYPE_EXTENSION => ['name', 'interfaces', 'directives', 'fields'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::INTERFACE_TYPE_EXTENSION => ['name', 'interfaces', 'directives', 'fields'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::UNION_TYPE_EXTENSION => ['name', 'directives', 'types'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::ENUM_TYPE_EXTENSION => ['name', 'directives', 'values'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::INPUT_OBJECT_TYPE_EXTENSION => ['name', 'directives', 'fields'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::DIRECTIVE_DEFINITION => ['description', 'name', 'arguments', 'locations'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::SCHEMA_EXTENSION => ['directives', 'operationTypes']]
removeNode()  : VisitorRemoveNode
Returns marker for removing the current node.
skipNode()  : VisitorSkipNode
Returns marker for skipping the subtree at the current node.
stop()  : VisitorStop
Returns marker for stopping.
visit()  : mixed
Visit the AST (see class description for details).
visitInParallel()  : VisitorArray
Combines the given visitors to run in parallel.
visitWithTypeInfo()  : array<string|int, mixed>
Creates a new visitor that updates TypeInfo and delegates to the given visitor.
extractVisitFn()  : callable|null

Constants

VISITOR_KEYS

public mixed VISITOR_KEYS = [AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::NAME => [], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::DOCUMENT => ['definitions'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::OPERATION_DEFINITION => ['name', 'variableDefinitions', 'directives', 'selectionSet'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::VARIABLE_DEFINITION => ['variable', 'type', 'defaultValue', 'directives'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::VARIABLE => ['name'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::SELECTION_SET => ['selections'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::FIELD => ['alias', 'name', 'arguments', 'directives', 'selectionSet'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::ARGUMENT => ['name', 'value'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::FRAGMENT_SPREAD => ['name', 'directives'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::INLINE_FRAGMENT => ['typeCondition', 'directives', 'selectionSet'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::FRAGMENT_DEFINITION => [ 'name', // Note: fragment variable definitions are experimental and may be changed // or removed in the future. 'variableDefinitions', 'typeCondition', 'directives', 'selectionSet', ], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::INT => [], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::FLOAT => [], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::STRING => [], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::BOOLEAN => [], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::NULL => [], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::ENUM => [], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::LST => ['values'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::OBJECT => ['fields'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::OBJECT_FIELD => ['name', 'value'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::DIRECTIVE => ['name', 'arguments'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::NAMED_TYPE => ['name'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::LIST_TYPE => ['type'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::NON_NULL_TYPE => ['type'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::SCHEMA_DEFINITION => ['description', 'directives', 'operationTypes'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::OPERATION_TYPE_DEFINITION => ['type'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::SCALAR_TYPE_DEFINITION => ['description', 'name', 'directives'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::OBJECT_TYPE_DEFINITION => ['description', 'name', 'interfaces', 'directives', 'fields'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::FIELD_DEFINITION => ['description', 'name', 'arguments', 'type', 'directives'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::INPUT_VALUE_DEFINITION => ['description', 'name', 'type', 'defaultValue', 'directives'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::INTERFACE_TYPE_DEFINITION => ['description', 'name', 'interfaces', 'directives', 'fields'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::UNION_TYPE_DEFINITION => ['description', 'name', 'directives', 'types'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::ENUM_TYPE_DEFINITION => ['description', 'name', 'directives', 'values'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::ENUM_VALUE_DEFINITION => ['description', 'name', 'directives'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::INPUT_OBJECT_TYPE_DEFINITION => ['description', 'name', 'directives', 'fields'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::SCALAR_TYPE_EXTENSION => ['name', 'directives'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::OBJECT_TYPE_EXTENSION => ['name', 'interfaces', 'directives', 'fields'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::INTERFACE_TYPE_EXTENSION => ['name', 'interfaces', 'directives', 'fields'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::UNION_TYPE_EXTENSION => ['name', 'directives', 'types'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::ENUM_TYPE_EXTENSION => ['name', 'directives', 'values'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::INPUT_OBJECT_TYPE_EXTENSION => ['name', 'directives', 'fields'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::DIRECTIVE_DEFINITION => ['description', 'name', 'arguments', 'locations'], AutomatticWooCommerceVendorGraphQLLanguageASTNodeKind::SCHEMA_EXTENSION => ['directives', 'operationTypes']]

Methods

visit()

Visit the AST (see class description for details).

public static visit(NodeList<string|int, Node>|Node $root, VisitorArray $visitor[, array<string, mixed>|null $keyMap = null ]) : mixed
Parameters
$root : NodeList<string|int, Node>|Node
$visitor : VisitorArray
$keyMap : array<string, mixed>|null = null
Tags
throws
Exception
Return values
mixed —

visitInParallel()

Combines the given visitors to run in parallel.

public static visitInParallel(array<string|int, mixed> $visitors) : VisitorArray
Parameters
$visitors : array<string|int, mixed>
Tags
phpstan-param

array<int, VisitorArray> $visitors

Return values
VisitorArray —

visitWithTypeInfo()

Creates a new visitor that updates TypeInfo and delegates to the given visitor.

public static visitWithTypeInfo(TypeInfo $typeInfo, array<string|int, mixed> $visitor) : array<string|int, mixed>
Parameters
$typeInfo : TypeInfo
$visitor : array<string|int, mixed>
Tags
phpstan-param

VisitorArray $visitor

phpstan-return

VisitorArray

Return values
array<string|int, mixed> —

extractVisitFn()

protected static extractVisitFn(array<string|int, mixed> $visitor, string $kind, bool $isLeaving) : callable|null
Parameters
$visitor : array<string|int, mixed>
$kind : string
$isLeaving : bool
Tags
phpstan-param

VisitorArray $visitor

Return values
callable|null —