From 48aea56c5ed8fda80caf3d1dbaa8b9dd2c8fd301 Mon Sep 17 00:00:00 2001
From: Ondrej Mirtes <ondrej@mirtes.cz>
Date: Mon, 8 Mar 2021 06:25:18 +0100
Subject: [PATCH] Nested generic type - correctly infer template types

---
 src/Type/Generic/TemplateTypeTrait.php        |  7 +++--
 .../Analyser/NodeScopeResolverTest.php        |  6 ++++
 tests/PHPStan/Analyser/data/bug-4642.php      | 28 +++++++++++++++++++
 .../data/nested-generic-types-unwrapping.php  |  4 +--
 .../Rules/Methods/CallMethodsRuleTest.php     |  8 ++++++
 5 files changed, 48 insertions(+), 5 deletions(-)
 create mode 100644 tests/PHPStan/Analyser/data/bug-4642.php

diff --git a/src/Type/Generic/TemplateTypeTrait.php b/src/Type/Generic/TemplateTypeTrait.php
index 9a7e857777..664a28805b 100644
--- a/src/Type/Generic/TemplateTypeTrait.php
+++ b/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
diff --git a/tests/PHPStan/Analyser/NodeScopeResolverTest.php b/tests/PHPStan/Analyser/NodeScopeResolverTest.php
index a7e733a0fe..258190aab0 100644
--- a/tests/PHPStan/Analyser/NodeScopeResolverTest.php
+++ b/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
diff --git a/tests/PHPStan/Analyser/data/bug-4642.php b/tests/PHPStan/Analyser/data/bug-4642.php
new file mode 100644
index 0000000000..7783fe4d59
--- /dev/null
+++ b/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));
+};
diff --git a/tests/PHPStan/Analyser/data/nested-generic-types-unwrapping.php b/tests/PHPStan/Analyser/data/nested-generic-types-unwrapping.php
index 3544e3cbf1..346448bd6f 100644
--- a/tests/PHPStan/Analyser/data/nested-generic-types-unwrapping.php
+++ b/tests/PHPStan/Analyser/data/nested-generic-types-unwrapping.php
@@ -103,7 +103,7 @@ function (): void {
 
 function (): void {
 	$result = loadWithIndirectUnwrap2(SomePackage::class);
-	assertType('NestedGenericTypesUnwrapping\GenericPackage<NestedGenericTypesUnwrapping\SomeInnerPackage>', $result);
+	assertType(SomePackage::class, $result);
 };
 
 function (SomePackage $somePackage): void {
@@ -111,5 +111,5 @@ function (SomePackage $somePackage): void {
 	assertType(SomeInnerPackage::class, $result);
 
 	$result = unwrapGeneric2($somePackage);
-	assertType('NestedGenericTypesUnwrapping\GenericPackage<NestedGenericTypesUnwrapping\SomeInnerPackage>', $result);
+	assertType(SomePackage::class, $result);
 };
diff --git a/tests/PHPStan/Rules/Methods/CallMethodsRuleTest.php b/tests/PHPStan/Rules/Methods/CallMethodsRuleTest.php
index 4118533763..ae12a3a262 100644
--- a/tests/PHPStan/Rules/Methods/CallMethodsRuleTest.php
+++ b/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'], []);
+	}
+
 }