Add TypeTraverser::mapMemoized()

src/Analyser/MutatingScope.php

@@ -2199,7 +2199,7 @@ public function enterPropertyHook(
 
 	private function transformStaticType(Type $type): Type
 	{
-		return TypeTraverser::map($type, new TransformStaticTypeTraverser($this));
+		return TypeTraverser::mapMemoized($type, new TransformStaticTypeTraverser($this));
 	}
 
 	/**

src/Analyser/PhpDocsResolver.php

@@ -279,7 +279,7 @@ private function getPhpDocReturnType(ResolvedPhpDocBlock $resolvedPhpDoc, Type $
 
 	private function transformStaticType(ClassReflection $declaringClass, Type $type): Type
 	{
-		return TypeTraverser::map($type, static function (Type $type, callable $traverse) use ($declaringClass): Type {
+		return TypeTraverser::mapMemoized($type, static function (Type $type, callable $traverse) use ($declaringClass): Type {
 			if ($type instanceof StaticType) {
 				$changedType = $type->changeBaseClass($declaringClass);
 				if ($declaringClass->isFinal() && !$type instanceof ThisType) {

src/Parser/TypeTraverserInstanceofVisitor.php

@@ -7,6 +7,7 @@
 use PhpParser\NodeVisitorAbstract;
 use PHPStan\DependencyInjection\AutowiredService;
 use PHPStan\Turbo\ShadowedByTurboExtension;
+use function in_array;
 
 #[AutowiredService]
 #[ShadowedByTurboExtension(implementation: __DIR__ . '/../../turbo-ext/src/TypeTraverserInstanceofVisitor.cpp')]
@@ -37,7 +38,7 @@ public function enterNode(Node $node): ?Node
 			&& $node->class instanceof Node\Name
 			&& $node->class->toLowerString() === 'phpstan\\type\\typetraverser'
 			&& $node->name instanceof Node\Identifier
-			&& $node->name->toLowerString() === 'map'
+			&& in_array($node->name->toLowerString(), ['map', 'mapmemoized'], true)
 		) {
 			$this->depth++;
 		}
@@ -53,7 +54,7 @@ public function leaveNode(Node $node): ?Node
 			&& $node->class instanceof Node\Name
 			&& $node->class->toLowerString() === 'phpstan\\type\\typetraverser'
 			&& $node->name instanceof Node\Identifier
-			&& $node->name->toLowerString() === 'map'
+			&& in_array($node->name->toLowerString(), ['map', 'mapmemoized'], true)
 		) {
 			$this->depth--;
 		}

src/Reflection/Type/CalledOnTypeUnresolvedMethodPrototypeReflection.php

@@ -143,7 +143,7 @@ private function transformMethodWithStaticType(ClassReflection $declaringClass,
 
 	private function transformStaticType(Type $type): Type
 	{
-		return TypeTraverser::map($type, function (Type $type, callable $traverse): Type {
+		return TypeTraverser::mapMemoized($type, function (Type $type, callable $traverse): Type {
 			if ($type instanceof GenericStaticType) {
 				$calledOnTypeReflections = $this->calledOnType->getObjectClassReflections();
 				if (count($calledOnTypeReflections) === 1) {

src/Rules/MissingTypehintCheck.php

@@ -30,6 +30,7 @@
 use function array_filter;
 use function array_keys;
 use function array_merge;
+use function array_values;
 use function count;
 use function implode;
 use function in_array;
@@ -73,7 +74,7 @@ public function __construct(
 	public function getIterableTypesWithMissingValueTypehint(Type $type): array
 	{
 		$descriptions = [];
-		TypeTraverser::map($type, function (Type $type, callable $traverse) use (&$descriptions): Type {
+		TypeTraverser::mapMemoized($type, function (Type $type, callable $traverse) use (&$descriptions): Type {
 			if ($type instanceof TemplateType) {
 				return $type;
 			}
@@ -98,17 +99,19 @@ public function getIterableTypesWithMissingValueTypehint(Type $type): array
 				return $traverse(new IntersectionType($nonArrayInner));
 			}
 			if ($type instanceof ConditionalType || $type instanceof ConditionalTypeForParameter) {
-				$descriptions = array_merge(
-					$descriptions,
+				$branchDescriptions = array_merge(
 					$this->getIterableTypesWithMissingValueTypehint($type->getIf()),
 					$this->getIterableTypesWithMissingValueTypehint($type->getElse()),
 				);
+				foreach ($branchDescriptions as $description) {
+					$descriptions[$description] = $description;
+				}
 
 				return $type;
 			}
 			if ($type->isIterable()->yes()) {
 				if ($type->isConstantArray()->yes()) {
-					$type = TypeTraverser::map($type, static function (Type $type, callable $traverse) {
+					$type = TypeTraverser::mapMemoized($type, static function (Type $type, callable $traverse) {
 						if ($type instanceof UnionType || $type instanceof IntersectionType) {
 							return $traverse($type);
 						}
@@ -125,7 +128,8 @@ public function getIterableTypesWithMissingValueTypehint(Type $type): array
 				}
 				$iterableValue = $type->getIterableValueType();
 				if ($iterableValue instanceof MixedType && !$iterableValue->isExplicitMixed()) {
-					$descriptions[] = sprintf('iterable type %s', $type->describe(VerbosityLevel::typeOnly()));
+					$description = sprintf('iterable type %s', $type->describe(VerbosityLevel::typeOnly()));
+					$descriptions[$description] = $description;
 				}
 				if ($type instanceof IntersectionType) {
 					if ($type->isList()->yes()) {
@@ -138,7 +142,7 @@ public function getIterableTypesWithMissingValueTypehint(Type $type): array
 			return $traverse($type);
 		});
 
-		return $descriptions;
+		return array_values($descriptions);
 	}
 
 	/**
@@ -147,7 +151,7 @@ public function getIterableTypesWithMissingValueTypehint(Type $type): array
 	public function getNonGenericObjectTypesWithGenericClass(Type $type): array
 	{
 		$objectTypes = [];
-		TypeTraverser::map($type, function (Type $type, callable $traverse) use (&$objectTypes): Type {
+		TypeTraverser::mapMemoized($type, function (Type $type, callable $traverse) use (&$objectTypes): Type {
 			if ($type instanceof GenericObjectType || $type instanceof GenericStaticType) {
 				$traverse($type);
 				return $type;
@@ -197,17 +201,15 @@ public function getNonGenericObjectTypesWithGenericClass(Type $type): array
 					$templateTypesList .= sprintf(' (%d-%d required)', $requiredTemplateTypesCount, $templateTypesCount);
 				}
 
-				$objectTypes[] = [
-					sprintf('%s %s', strtolower($classReflection->getClassTypeDescription()), $classReflection->getDisplayName(false)),
-					$templateTypesList,
-				];
+				$name = sprintf('%s %s', strtolower($classReflection->getClassTypeDescription()), $classReflection->getDisplayName(false));
+				$objectTypes[$name . "\0" . $templateTypesList] = [$name, $templateTypesList];
 				return $type;
 			}
 
 			return $traverse($type);
 		});
 
-		return $objectTypes;
+		return array_values($objectTypes);
 	}
 
 	/**

src/Rules/PhpDoc/UnresolvableTypeHelper.php

@@ -8,7 +8,6 @@
 use PHPStan\Type\NeverType;
 use PHPStan\Type\Type;
 use PHPStan\Type\TypeTraverser;
-use function array_unique;
 use function array_values;
 
 #[AutowiredService]
@@ -20,7 +19,7 @@ public function getUnresolvableType(Type $type): ?UnresolvableTypeResult
 	{
 		$containsUnresolvable = false;
 		$reasons = [];
-		TypeTraverser::map($type, static function (Type $type, callable $traverse) use (&$containsUnresolvable, &$reasons): Type {
+		TypeTraverser::mapMemoized($type, static function (Type $type, callable $traverse) use (&$containsUnresolvable, &$reasons): Type {
 			$reason = null;
 			if ($type instanceof ErrorType) {
 				$containsUnresolvable = true;
@@ -32,7 +31,7 @@ public function getUnresolvableType(Type $type): ?UnresolvableTypeResult
 			}
 
 			if ($reason !== null) {
-				$reasons[] = $reason;
+				$reasons[$reason] = $reason;
 			}
 
 			return $containsUnresolvable ? $type : $traverse($type);
@@ -42,7 +41,7 @@ public function getUnresolvableType(Type $type): ?UnresolvableTypeResult
 			return null;
 		}
 
-		return new UnresolvableTypeResult(array_values(array_unique($reasons)));
+		return new UnresolvableTypeResult(array_values($reasons));
 	}
 
 }

src/Rules/RuleLevelHelper.php

@@ -112,7 +112,7 @@ private function transformCommonType(Type $type): Type
 	private function transformAcceptedType(Type $acceptingType, Type $acceptedType): array
 	{
 		$checkForUnion = $this->checkUnionTypes;
-		$acceptedType = TypeTraverser::map($acceptedType, function (Type $acceptedType, callable $traverse) use ($acceptingType, &$checkForUnion): Type {
+		$acceptedType = TypeTraverser::mapMemoized($acceptedType, function (Type $acceptedType, callable $traverse) use ($acceptingType, &$checkForUnion): Type {
 			if ($acceptedType instanceof CallableType) {
 				if ($acceptedType->isCommonCallable()) {
 					return $acceptedType;

src/Turbo/TurboExtensionEnabler.php

@@ -33,7 +33,7 @@
 final class TurboExtensionEnabler
 {
 
-	public const EXPECTED_EXTENSION_VERSION = '33df0ad';
+	public const EXPECTED_EXTENSION_VERSION = 'daff12b';
 
 	private static bool $active = false;
 

src/Type/Generic/TemplateTypeHelper.php

@@ -106,7 +106,7 @@ public static function resolveToDefaults(Type $type): Type
 
 	public static function resolveToBounds(Type $type): Type
 	{
-		return TypeTraverser::map($type, static function (Type $type, callable $traverse): Type {
+		return TypeTraverser::mapMemoized($type, static function (Type $type, callable $traverse): Type {
 			while ($type instanceof TemplateType) {
 				$type = $type->getBound();
 			}

src/Type/TypeTraverser.php

@@ -3,6 +3,7 @@
 namespace PHPStan\Type;
 
 use PHPStan\Turbo\ShadowedByTurboExtension;
+use function spl_object_id;
 
 #[ShadowedByTurboExtension(implementation: __DIR__ . '/../../turbo-ext/src/TypeTraverser.cpp')]
 final class TypeTraverser
@@ -11,6 +12,15 @@ final class TypeTraverser
 	/** @var callable(Type $type, callable(Type): Type $traverse): Type */
 	private $cb;
 
+	/**
+	 * Results of mapMemoized() keyed by spl_object_id() of the mapped type,
+	 * null in map(). The mapped type is kept alive next to its result so that
+	 * its id cannot be reused by another object during the traversal.
+	 *
+	 * @var array<int, array{Type, Type}>|null
+	 */
+	private ?array $memo = null;
+
 	/**
 	 * Map a Type recursively
 	 *
@@ -43,6 +53,27 @@ public static function map(Type $type, TypeTraverserCallable|callable $cb): Type
 		return $self->mapInternal($type);
 	}
 
+	/**
+	 * Like map(), but the callback is called only once for each Type instance:
+	 * a Type instance occurring repeatedly in the traversed type (e.g. a type
+	 * alias used in many offsets of an array shape) is replaced with the result
+	 * of its first occurrence, without traversing it again.
+	 *
+	 * Only for callbacks whose result and side effects do not depend on
+	 * where in the traversed type, or how many times, the type occurs.
+	 *
+	 * @param TypeTraverserCallable|callable(Type $type, callable(Type): Type $traverse): Type $cb
+	 */
+	public static function mapMemoized(Type $type, TypeTraverserCallable|callable $cb): Type
+	{
+		$self = new self($cb);
+		$self->memo = [];
+
+		$traverser = $self->mapInternal($type);
+		$self->memo = null;
+		return $traverser;
+	}
+
 	/** @param TypeTraverserCallable|callable(Type $type, callable(Type): Type $traverse): Type $cb */
 	private function __construct(TypeTraverserCallable|callable $cb)
 	{
@@ -56,7 +87,19 @@ private function __construct(TypeTraverserCallable|callable $cb)
 	/** @internal */
 	public function mapInternal(Type $type): Type
 	{
-		return ($this->cb)($type, [$this, 'traverseInternal']);
+		if ($this->memo === null) {
+			return ($this->cb)($type, [$this, 'traverseInternal']);
+		}
+
+		$id = spl_object_id($type);
+		if (isset($this->memo[$id])) {
+			return $this->memo[$id][1];
+		}
+
+		$result = ($this->cb)($type, [$this, 'traverseInternal']);
+		$this->memo[$id] = [$type, $result];
+
+		return $result;
 	}
 
 	/** @internal */

tests/PHPStan/Rules/Api/ApiInstanceofTypeRuleTest.php

@@ -40,6 +40,11 @@ public function testRule(): void
 				40,
 				$tipText,
 			],
+			[
+				'Doing instanceof PHPStan\Type\Generic\GenericObjectType is error-prone and deprecated.',
+				52,
+				$tipText,
+			],
 		]);
 	}
 

tests/PHPStan/Rules/Api/data/instanceof-type.php

@@ -40,6 +40,18 @@ public function doFoo($a, Type $type)
 		if ($a instanceof GenericObjectType) {
 
 		}
+
+		$type = TypeTraverser::mapMemoized($type, function (Type $type, callable $traverse): Type {
+			if ($type instanceof TypeWithClassName) {
+				return $type;
+			}
+
+			return $traverse($type);
+		});
+
+		if ($a instanceof GenericObjectType) {
+
+		}
 	}
 
 }

tests/PHPStan/Rules/Methods/MissingMethodParameterTypehintRuleTest.php

@@ -160,11 +160,32 @@ public function testBug14549(): void
 				46,
 				MissingTypehintCheck::MISSING_ITERABLE_VALUE_TYPE_TIP,
 			],
+		]);
+	}
+
+	public function testRepeatedIterableTypeReportedOnce(): void
+	{
+		// the same missing value type or generic class is reported once per parameter,
+		// regardless of whether the occurrences share a Type instance (type alias) or not
+		$this->analyse([__DIR__ . '/data/bug-15350.php'], [
 			[
-				'Method Bug14549\Foo::doIntersection() has parameter $array with no value type specified in iterable type array.',
-				46,
+				'Method Bug15350\\Foo::inline() has parameter $a with no value type specified in iterable type array.',
+				23,
 				MissingTypehintCheck::MISSING_ITERABLE_VALUE_TYPE_TIP,
 			],
+			[
+				'Method Bug15350\\Foo::alias() has parameter $a with no value type specified in iterable type array.',
+				30,
+				MissingTypehintCheck::MISSING_ITERABLE_VALUE_TYPE_TIP,
+			],
+			[
+				'Method Bug15350\\Foo::inlineGeneric() has parameter $a with generic class Bug15350\\Box but does not specify its types: T',
+				37,
+			],
+			[
+				'Method Bug15350\\Foo::aliasGeneric() has parameter $a with generic class Bug15350\\Box but does not specify its types: T',
+				44,
+			],
 		]);
 	}
 

tests/PHPStan/Rules/Methods/data/bug-15350.php

@@ -0,0 +1,48 @@
+<?php
+
+namespace Bug15350;
+
+/**
+ * @template T
+ */
+class Box
+{
+
+}
+
+/**
+ * @phpstan-type BareArr array
+ * @phpstan-type BareBox Box
+ */
+class Foo
+{
+
+	/**
+	 * @param callable(array): array $a
+	 */
+	public function inline($a): void
+	{
+	}
+
+	/**
+	 * @param callable(BareArr): BareArr $a
+	 */
+	public function alias($a): void
+	{
+	}
+
+	/**
+	 * @param callable(Box): Box $a
+	 */
+	public function inlineGeneric($a): void
+	{
+	}
+
+	/**
+	 * @param callable(BareBox): BareBox $a
+	 */
+	public function aliasGeneric($a): void
+	{
+	}
+
+}