* * For the full copyright and license information, please view the LICENSE * file that was distributed with this source code. */ namespace SebastianBergmann\Type; use function array_unique; use function assert; use function count; use function implode; use function sort; final class IntersectionType extends Type { /** * @psalm-var non-empty-list */ private $types; /** * @throws RuntimeException */ public function __construct(Type ...$types) { $this->ensureMinimumOfTwoTypes(...$types); $this->ensureOnlyValidTypes(...$types); $this->ensureNoDuplicateTypes(...$types); $this->types = $types; } public function isAssignable(Type $other): bool { return $other->isObject(); } public function asString(): string { return $this->name(); } public function name(): string { $types = []; foreach ($this->types as $type) { $types[] = $type->name(); } sort($types); return implode('&', $types); } public function allowsNull(): bool { return false; } /** * @psalm-assert-if-true IntersectionType $this */ public function isIntersection(): bool { return true; } /** * @psalm-return non-empty-list */ public function types(): array { return $this->types; } /** * @throws RuntimeException */ private function ensureMinimumOfTwoTypes(Type ...$types): void { if (count($types) < 2) { throw new RuntimeException( 'An intersection type must be composed of at least two types' ); } } /** * @throws RuntimeException */ private function ensureOnlyValidTypes(Type ...$types): void { foreach ($types as $type) { if (!$type->isObject()) { throw new RuntimeException( 'An intersection type can only be composed of interfaces and classes' ); } } } /** * @throws RuntimeException */ private function ensureNoDuplicateTypes(Type ...$types): void { $names = []; foreach ($types as $type) { assert($type instanceof ObjectType); $names[] = $type->className()->qualifiedName(); } if (count(array_unique($names)) < count($names)) { throw new RuntimeException( 'An intersection type must not contain duplicate types' ); } } }