Nested generic type - correctly infer template types

Author: ondrejmirtes

src/Type/Generic/TemplateTypeTrait.php

@@ -158,14 +158,15 @@ public function inferTemplateTypes(Type $receivedType): TemplateTypeMap
 			]);
 		}
 
-		$resolvedBound = TemplateTypeHelper::resolveToBounds($this->getBound());
+		$map = $this->getBound()->inferTemplateTypes($receivedType);
+		$resolvedBound = TemplateTypeHelper::resolveTemplateTypes($this->getBound(), $map);
 		if ($resolvedBound->isSuperTypeOf($receivedType)->yes()) {
 			return (new TemplateTypeMap([
 				$this->name => $this->shouldGeneralizeInferredType() ? TemplateTypeHelper::generalizeType($receivedType) : $receivedType,
-			]))->union($this->getBound()->inferTemplateTypes($receivedType));
+			]))->union($map);
 		}
 
-		return $this->getBound()->inferTemplateTypes($receivedType);
+		return $map;
 	}
 
 	public function getReferencedTemplateTypes(TemplateTypeVariance $positionVariance): array

tests/PHPStan/Analyser/NodeScopeResolverTest.php

@@ -10961,6 +10961,11 @@ public function dataIteratorIterator(): array
 		return $this->gatherAssertTypes(__DIR__ . '/data/iterator-iterator.php');
 	}
 
+	public function dataBug4642(): array
+	{
+		return $this->gatherAssertTypes(__DIR__ . '/data/bug-4642.php');
+	}
+
 	/**
 	 * @param string $file
 	 * @return array<string, mixed[]>
@@ -11214,6 +11219,7 @@ private function gatherAssertTypes(string $file): array
 	 * @dataProvider dataNestedGenericTypesUnwrapping
 	 * @dataProvider dataNestedGenericIncompleteConstructor
 	 * @dataProvider dataIteratorIterator
+	 * @dataProvider dataBug4642
 	 * @param string $assertType
 	 * @param string $file
 	 * @param mixed ...$args

tests/PHPStan/Analyser/data/bug-4642.php

@@ -0,0 +1,28 @@
+<?php
+
+namespace Bug4642;
+
+use function PHPStan\Analyser\assertType;
+
+interface IEntity {}
+/** @template E of IEntity */
+interface IRepository {}
+
+interface I {
+	/**
+	 * Returns repository by repository class.
+	 * @template E of IEntity
+	 * @template T of IRepository<E>
+	 * @phpstan-param class-string<T> $className
+	 * @phpstan-return T
+	 */
+	function getRepository(string $className): IRepository;
+}
+
+class User implements IEntity {}
+/** @implements IRepository<User> */
+class UsersRepository implements IRepository {}
+
+function (I $model): void {
+	assertType(UsersRepository::class, $model->getRepository(UsersRepository::class));
+};

tests/PHPStan/Analyser/data/nested-generic-types-unwrapping.php

@@ -103,13 +103,13 @@ function (): void {
 
 function (): void {
 	$result = loadWithIndirectUnwrap2(SomePackage::class);
-	assertType('NestedGenericTypesUnwrapping\GenericPackage<NestedGenericTypesUnwrapping\SomeInnerPackage>', $result);
+	assertType(SomePackage::class, $result);
 };
 
 function (SomePackage $somePackage): void {
 	$result = unwrapGeneric($somePackage);
 	assertType(SomeInnerPackage::class, $result);
 
 	$result = unwrapGeneric2($somePackage);
-	assertType('NestedGenericTypesUnwrapping\GenericPackage<NestedGenericTypesUnwrapping\SomeInnerPackage>', $result);
+	assertType(SomePackage::class, $result);
 };

tests/PHPStan/Rules/Methods/CallMethodsRuleTest.php

@@ -1883,4 +1883,12 @@ public function testBug3922(): void
 		]);
 	}
 
+	public function testBug4642(): void
+	{
+		$this->checkThisOnly = false;
+		$this->checkNullables = true;
+		$this->checkUnionTypes = true;
+		$this->analyse([__DIR__ . '/../../Analyser/data/bug-4642.php'], []);
+	}
+
 }