Move template type bound check from VarTagTypeRuleHelper to TemplateTypeVariance

Instead of special-casing GenericObjectType in VarTagTypeRuleHelper,
handle the template type equivalence at the type system level: in the
invariant variance check, when the other type ($b) is a TemplateType
whose bound equals $a, consider them equivalent.

This approach uses the existing $acceptsContext infrastructure direction
rather than adding rule-level workarounds.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: phpstan-bot

phpstan-baseline.neon

@@ -726,7 +726,7 @@ parameters:
 		-
 			rawMessage: Doing instanceof PHPStan\Type\Generic\GenericObjectType is error-prone and deprecated.
 			identifier: phpstanApi.instanceofType
-			count: 3
+			count: 1
 			path: src/Rules/PhpDoc/VarTagTypeRuleHelper.php
 
 		-

src/Rules/PhpDoc/VarTagTypeRuleHelper.php

@@ -177,23 +177,6 @@ private function shouldVarTagTypeBeReported(Scope $scope, Node\Expr $expr, Type
 
 	private function checkType(Scope $scope, Type $type, Type $varTagType, int $depth = 0): bool
 	{
-		if (
-			$type instanceof GenericObjectType
-			&& $varTagType instanceof GenericObjectType
-			&& $type->getClassName() === $varTagType->getClassName()
-		) {
-			$typeArgs = $type->getTypes();
-			$varTagArgs = $varTagType->getTypes();
-			if (count($typeArgs) === count($varTagArgs)) {
-				foreach ($typeArgs as $i => $typeArg) {
-					if ($this->checkType($scope, $typeArg, $varTagArgs[$i], $depth + 1)) {
-						return true;
-					}
-				}
-				return false;
-			}
-		}
-
 		if ($this->strictWideningCheck) {
 			return !$this->isSuperTypeOfVarType($scope, $type, $varTagType);
 		}

src/Type/Generic/TemplateTypeVariance.php

@@ -177,6 +177,9 @@ public function isValidVariance(TemplateType $templateType, Type $a, Type $b): I
 
 		if ($this->invariant()) {
 			$result = $a->equals($b);
+			if (!$result && $b instanceof TemplateType && $a->equals($b->getBound())) {
+				$result = true;
+			}
 			$reasons = [];
 			if (!$result) {
 				if (