PHPStan Utilities

This is a collection of PHPStan utilities you can use to transform types.

Installation

composer require vixducis/phpstan-utilities

Afterwards, add the following section to your phpstan.neon configuration file:

includes:
- vendor/vixducis/phpstan-utilities/extension.neon

Utilities

This package provides several type transformation utilities for use with PHPStan. Each utility can be used as a generic type in your PHPDoc or PHPStan configuration.

ArrayValues

Sometimes, you'll have a template type that contains a template, but you still want to extract the values from it.

Usage:

/** @var ArrayValues<T> */

This utility extracts the value types from an array type T. If T is an array, it returns the type of its values. Otherwise, it returns an error type.

This differs from value-of: value-of<array{a:int,b:string}> will return int|string. ArrayValues<array{a:int,b:string}> will return array{int,string}.

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UnwrapSingletonArray

This utility unwraps a singleton array type, i.e., if the type is an array containing exactly one element, it yields both the original array type and the value type as a union. Otherwise, it returns the original type.

Usage:

/** @var UnwrapSingletonArray<T> */

• If T is an array of exactly one element, returns T|V (where V is the value type).
• Otherwise, returns T.

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UnionToIntersection

This utility converts a union type into an intersection type.

Usage:

/** @var UnionToIntersection<T> */

If T is a union type (e.g., A|B), UnionToIntersection<T> produces an intersection (e.g., A&B). If T is not a union, returns an error type.