IterableType.php

<?php declare(strict_types = 1);

namespace PHPStan\Type;

use PHPStan\TrinaryLogic;
use PHPStan\Type\Constant\ConstantArrayType;
use PHPStan\Type\Generic\TemplateMixedType;
use PHPStan\Type\Generic\TemplateType;
use PHPStan\Type\Generic\TemplateTypeMap;
use PHPStan\Type\Generic\TemplateTypeVariance;
use PHPStan\Type\Traits\MaybeCallableTypeTrait;
use PHPStan\Type\Traits\MaybeObjectTypeTrait;
use PHPStan\Type\Traits\MaybeOffsetAccessibleTypeTrait;
use PHPStan\Type\Traits\UndecidedBooleanTypeTrait;
use PHPStan\Type\Traits\UndecidedComparisonCompoundTypeTrait;

class IterableType implements CompoundType, ImplementsSubTypeOfUnion
{

	use MaybeCallableTypeTrait;
	use MaybeObjectTypeTrait;
	use MaybeOffsetAccessibleTypeTrait;
	use UndecidedBooleanTypeTrait;
	use UndecidedComparisonCompoundTypeTrait;

	private \PHPStan\Type\Type $keyType;

	private \PHPStan\Type\Type $itemType;

	public function __construct(
		Type $keyType,
		Type $itemType
	)
	{
		$this->keyType = $keyType;
		$this->itemType = $itemType;
	}

	public function getKeyType(): Type
	{
		return $this->keyType;
	}

	public function getItemType(): Type
	{
		return $this->itemType;
	}

	/**
	 * @return string[]
	 */
	public function getReferencedClasses(): array
	{
		return array_merge(
			$this->keyType->getReferencedClasses(),
			$this->getItemType()->getReferencedClasses()
		);
	}

	public function accepts(Type $type, bool $strictTypes): TrinaryLogic
	{
		if ($type instanceof ConstantArrayType && $type->isEmpty()) {
			return TrinaryLogic::createYes();
		}
		if ($type->isIterable()->yes()) {
			return $this->getIterableValueType()->accepts($type->getIterableValueType(), $strictTypes)
				->and($this->getIterableKeyType()->accepts($type->getIterableKeyType(), $strictTypes));
		}

		if ($type instanceof CompoundType) {
			return CompoundTypeHelper::accepts($type, $this, $strictTypes);
		}

		return TrinaryLogic::createNo();
	}

	public function isSuperTypeOf(Type $type): TrinaryLogic
	{
		return $type->isIterable()
			->and($this->getIterableValueType()->isSuperTypeOf($type->getIterableValueType()))
			->and($this->getIterableKeyType()->isSuperTypeOf($type->getIterableKeyType()));
	}

	public function isSuperTypeOfMixed(Type $type): TrinaryLogic
	{
		return $type->isIterable()
			->and($this->isNestedTypeSuperTypeOf($this->getIterableValueType(), $type->getIterableValueType()))
			->and($this->isNestedTypeSuperTypeOf($this->getIterableKeyType(), $type->getIterableKeyType()));
	}

	private function isNestedTypeSuperTypeOf(Type $a, Type $b): TrinaryLogic
	{
		if (!$a instanceof MixedType || !$b instanceof MixedType) {
			return $a->isSuperTypeOf($b);
		}

		if ($a instanceof TemplateMixedType || $b instanceof TemplateMixedType) {
			return $a->isSuperTypeOf($b);
		}

		if ($a->isExplicitMixed()) {
			if ($b->isExplicitMixed()) {
				return TrinaryLogic::createYes();
			}

			return TrinaryLogic::createMaybe();
		}

		return TrinaryLogic::createYes();
	}

	public function isSubTypeOf(Type $otherType): TrinaryLogic
	{
		if ($otherType instanceof IntersectionType || $otherType instanceof UnionType) {
			return $otherType->isSuperTypeOf(new UnionType([
				new ArrayType($this->keyType, $this->itemType),
				new IntersectionType([
					new ObjectType(\Traversable::class),
					$this,
				]),
			]));
		}

		if ($otherType instanceof self) {
			$limit = TrinaryLogic::createYes();
		} else {
			$limit = TrinaryLogic::createMaybe();
		}

		if ($otherType instanceof ConstantArrayType && $otherType->isEmpty()) {
			return TrinaryLogic::createMaybe();
		}

		return $limit->and(
			$otherType->isIterable(),
			$otherType->getIterableValueType()->isSuperTypeOf($this->itemType),
			$otherType->getIterableKeyType()->isSuperTypeOf($this->keyType)
		);
	}

	public function isAcceptedBy(Type $acceptingType, bool $strictTypes): TrinaryLogic
	{
		return $this->isSubTypeOf($acceptingType);
	}

	public function equals(Type $type): bool
	{
		if (!$type instanceof self) {
			return false;
		}

		return $this->keyType->equals($type->keyType)
			&& $this->itemType->equals($type->itemType);
	}

	public function describe(VerbosityLevel $level): string
	{
		$isMixedKeyType = $this->keyType instanceof MixedType && !$this->keyType instanceof TemplateType;
		$isMixedItemType = $this->itemType instanceof MixedType && !$this->itemType instanceof TemplateType;

		if ($isMixedKeyType) {
			if ($isMixedItemType) {
				return 'iterable';
			}

			return sprintf('iterable<%s>', $this->itemType->describe($level));
		}

		return sprintf('iterable<%s, %s>', $this->keyType->describe($level), $this->itemType->describe($level));
	}

	public function hasOffsetValueType(Type $offsetType): TrinaryLogic
	{
		if ($this->getIterableKeyType()->isSuperTypeOf($offsetType)->no()) {
			return TrinaryLogic::createNo();
		}

		return TrinaryLogic::createMaybe();
	}

	public function toNumber(): Type
	{
		return new ErrorType();
	}

	public function toString(): Type
	{
		return new ErrorType();
	}

	public function toInteger(): Type
	{
		return new ErrorType();
	}

	public function toFloat(): Type
	{
		return new ErrorType();
	}

	public function toArray(): Type
	{
		return new ArrayType($this->keyType, $this->getItemType());
	}

	public function isIterable(): TrinaryLogic
	{
		return TrinaryLogic::createYes();
	}

	public function isIterableAtLeastOnce(): TrinaryLogic
	{
		return TrinaryLogic::createMaybe();
	}

	public function getIterableKeyType(): Type
	{
		return $this->keyType;
	}

	public function getIterableValueType(): Type
	{
		return $this->getItemType();
	}

	public function isArray(): TrinaryLogic
	{
		return TrinaryLogic::createMaybe();
	}

	public function isNumericString(): TrinaryLogic
	{
		return TrinaryLogic::createNo();
	}

	public function inferTemplateTypes(Type $receivedType): TemplateTypeMap
	{
		if ($receivedType instanceof UnionType || $receivedType instanceof IntersectionType) {
			return $receivedType->inferTemplateTypesOn($this);
		}

		if (!$receivedType->isIterable()->yes()) {
			return TemplateTypeMap::createEmpty();
		}

		$keyTypeMap = $this->getIterableKeyType()->inferTemplateTypes($receivedType->getIterableKeyType());
		$valueTypeMap = $this->getIterableValueType()->inferTemplateTypes($receivedType->getIterableValueType());

		return $keyTypeMap->union($valueTypeMap);
	}

	public function getReferencedTemplateTypes(TemplateTypeVariance $positionVariance): array
	{
		return array_merge(
			$this->getIterableKeyType()->getReferencedTemplateTypes(TemplateTypeVariance::createCovariant()),
			$this->getIterableValueType()->getReferencedTemplateTypes(TemplateTypeVariance::createCovariant())
		);
	}

	public function traverse(callable $cb): Type
	{
		$keyType = $cb($this->keyType);
		$itemType = $cb($this->itemType);

		if ($keyType !== $this->keyType || $itemType !== $this->itemType) {
			return new self($keyType, $itemType);
		}

		return $this;
	}

	/**
	 * @param mixed[] $properties
	 * @return Type
	 */
	public static function __set_state(array $properties): Type
	{
		return new self($properties['keyType'], $properties['itemType']);
	}

}