TemplateTypeCheck - look for nested unsupported types

Author: ondrejmirtes

src/Rules/Generics/TemplateTypeCheck.php

@@ -11,6 +11,8 @@
 use PHPStan\Type\MixedType;
 use PHPStan\Type\ObjectType;
 use PHPStan\Type\ObjectWithoutClassType;
+use PHPStan\Type\Type;
+use PHPStan\Type\TypeTraverser;
 use PHPStan\Type\UnionType;
 use PHPStan\Type\VerbosityLevel;
 use function array_key_exists;
@@ -101,18 +103,21 @@ public function check(
 $messages = array_merge($messages, $this->classCaseSensitivityCheck->checkClassNames($classNameNodePairs));
 }
 
-$bound = $templateTag->getBound();
-$boundClass = get_class($bound);
-if (
-$boundClass === MixedType::class
-|| $boundClass === ObjectWithoutClassType::class
-|| $bound instanceof ObjectType
-|| $bound instanceof UnionType
-) {
-continue;
-}
+TypeTraverser::map($templateTag->getBound(), static function (Type $type, callable $traverse) use (&$messages, $notSupportedBoundMessage, $templateTagName): Type {
+$boundClass = get_class($type);
+if (
+$boundClass === MixedType::class
+|| $boundClass === ObjectWithoutClassType::class
+|| $boundClass === ObjectType::class
+|| $type instanceof UnionType
+) {
+return $traverse($type);
+}
+
+$messages[] = RuleErrorBuilder::message(sprintf($notSupportedBoundMessage, $templateTagName, $type->describe(VerbosityLevel::typeOnly())))->build();
 
-$messages[] = RuleErrorBuilder::message(sprintf($notSupportedBoundMessage, $templateTagName, $boundType->describe(VerbosityLevel::typeOnly())))->build();
+return $type;
+});
 }
 
 return $messages;

src/Type/Generic/TemplateTypeFactory.php

@@ -21,11 +21,10 @@ public static function create(TemplateTypeScope $scope, string $name, ?Type $bou
 return new TemplateMixedType($scope, $strategy, $variance, $name);
 }
 
-if ($bound instanceof ObjectType) {
+$boundClass = get_class($bound);
+if ($boundClass === ObjectType::class) {
 return new TemplateObjectType($scope, $strategy, $variance, $name, $bound->getClassName());
 }
-
-$boundClass = get_class($bound);
 if ($boundClass === ObjectWithoutClassType::class) {
 return new TemplateObjectWithoutClassType($scope, $strategy, $variance, $name);
 }

tests/PHPStan/Rules/Generics/InterfaceTemplateTypeRuleTest.php

@@ -41,6 +41,10 @@ public function testRule(): void
 'PHPDoc tag @template for interface InterfaceTemplateType\Lorem cannot have existing type alias TypeAlias as its name.',
 32,
 ],
+[
+'PHPDoc tag @template T for interface InterfaceTemplateType\UnionBound with bound type InterfaceTemplateType\NormalT<stdClass> is not supported.',
+44,
+],
 ]);
 }
 

tests/PHPStan/Rules/Generics/data/interface-template.php

@@ -33,3 +33,15 @@ interface Lorem
 {
 
 }
+
+/** @template T */
+interface NormalT
+{
+
+}
+
+/** @template T of NormalT<\stdClass>|\stdClass */
+interface UnionBound
+{
+
+}