Explicitly disallow defining type parameters in constructor

phpstan · Dec 10, 2022 · fb0faa4 · fb0faa4
1 parent 473c0f2
commit fb0faa4
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Showing 3 changed files with 30 additions and 3 deletions.
diff --git a/src/Rules/Generics/VarianceCheck.php b/src/Rules/Generics/VarianceCheck.php
@@ -27,8 +27,22 @@ public function checkParametersAcceptor(
 		$errors = [];
 
 		foreach ($parametersAcceptor->getTemplateTypeMap()->getTypes() as $templateType) {
-			if (!$templateType instanceof TemplateType
-				|| $templateType->getScope()->getFunctionName() === null
+			if (!$templateType instanceof TemplateType) {
+				continue;
+			}
+
+			if ($templateType->getScope()->getClassName() !== null
+				&& $templateType->getScope()->getFunctionName() === '__construct'
+			) {
+				$errors[] = RuleErrorBuilder::message(sprintf(
+					'Constructor is not allowed to define type parameters, but template type %s is defined %s.',
+					$templateType->getName(),
+					$generalMessage,
+				))->build();
+				continue;
+			}
+
+			if ($templateType->getScope()->getFunctionName() === null
 				|| $templateType->getVariance()->invariant()
 			) {
 				continue;

diff --git a/tests/PHPStan/Rules/Generics/MethodSignatureVarianceRuleTest.php b/tests/PHPStan/Rules/Generics/MethodSignatureVarianceRuleTest.php
@@ -186,7 +186,12 @@ public function testRule(): void
 			],
 		]);
 
-		$this->analyse([__DIR__ . '/data/method-signature-variance-constructor.php'], []);
+		$this->analyse([__DIR__ . '/data/method-signature-variance-constructor.php'], [
+			[
+				'Constructor is not allowed to define type parameters, but template type Y is defined in method MethodSignatureVariance\Constructor\D::__construct().',
+				79,
+			],
+		]);
 	}
 
 }
diff --git a/tests/PHPStan/Rules/Generics/data/method-signature-variance-constructor.php b/tests/PHPStan/Rules/Generics/data/method-signature-variance-constructor.php
@@ -70,3 +70,11 @@ class C {
 	 */
 	function __construct($a, $b, $c, $d, $e, $f, $g, $h, $i, $j, $k, $l) {}
 }
+
+/** @template X */
+class D {
+	/**
+	 * @template Y of X
+	 */
+	function __construct() {}
+}