Add InvalidCallablePropertyTypeRule

Author: paulbalandan

Makefile

@@ -40,6 +40,7 @@ lint:
 		--exclude tests/PHPStan/Rules/Functions/data/arrow-function-nullsafe-by-ref.php \
 		--exclude tests/PHPStan/Levels/data/namedArguments.php \
 		--exclude tests/PHPStan/Rules/Keywords/data/continue-break.php \
+		--exclude tests/PHPStan/Rules/Properties/data/invalid-callable-property-type.php \
 		--exclude tests/PHPStan/Rules/Properties/data/properties-in-interface.php \
 		--exclude tests/PHPStan/Rules/Properties/data/read-only-property.php \
 		--exclude tests/PHPStan/Rules/Properties/data/read-only-property-phpdoc-and-native.php   \

conf/config.level0.neon

@@ -88,6 +88,7 @@ rules:
 	- PHPStan\Rules\Operators\InvalidAssignVarRule
 	- PHPStan\Rules\Properties\AccessPropertiesInAssignRule
 	- PHPStan\Rules\Properties\AccessStaticPropertiesInAssignRule
+	- PHPStan\Rules\Properties\InvalidCallablePropertyTypeRule
 	- PHPStan\Rules\Properties\MissingReadOnlyPropertyAssignRule
 	- PHPStan\Rules\Properties\PropertiesInInterfaceRule
 	- PHPStan\Rules\Properties\PropertyAttributesRule

src/Rules/Properties/InvalidCallablePropertyTypeRule.php

@@ -0,0 +1,65 @@
+<?php declare(strict_types = 1);
+
+namespace PHPStan\Rules\Properties;
+
+use PhpParser\Node;
+use PHPStan\Analyser\Scope;
+use PHPStan\Node\ClassPropertyNode;
+use PHPStan\Rules\Rule;
+use PHPStan\Rules\RuleErrorBuilder;
+use PHPStan\Type\CallableType;
+use PHPStan\Type\IntersectionType;
+use PHPStan\Type\Type;
+use PHPStan\Type\TypeTraverser;
+use PHPStan\Type\UnionType;
+use function sprintf;
+
+/**
+ * @implements Rule<ClassPropertyNode>
+ */
+class InvalidCallablePropertyTypeRule implements Rule
+{
+
+	public function getNodeType(): string
+	{
+		return ClassPropertyNode::class;
+	}
+
+	public function processNode(Node $node, Scope $scope): array
+	{
+		$classReflection = $node->getClassReflection();
+		$propertyReflection = $classReflection->getNativeProperty($node->getName());
+
+		if (!$propertyReflection->hasNativeType()) {
+			return [];
+		}
+
+		$nativeType = $propertyReflection->getNativeType();
+		$callableTypes = [];
+
+		TypeTraverser::map($nativeType, static function (Type $type, callable $traverse) use (&$callableTypes): Type {
+			if ($type instanceof UnionType || $type instanceof IntersectionType) {
+				return $traverse($type);
+			}
+
+			if ($type instanceof CallableType) {
+				$callableTypes[] = $type;
+			}
+
+			return $type;
+		});
+
+		if ($callableTypes === []) {
+			return [];
+		}
+
+		return [
+			RuleErrorBuilder::message(sprintf(
+				'Property %s::$%s cannot have callable in its type declaration.',
+				$classReflection->getDisplayName(),
+				$node->getName(),
+			))->identifier('property.callableType')->nonIgnorable()->build(),
+		];
+	}
+
+}

tests/PHPStan/Rules/Properties/InvalidCallablePropertyTypeRuleTest.php

@@ -0,0 +1,41 @@
+<?php declare(strict_types = 1);
+
+namespace PHPStan\Rules\Properties;
+
+use PHPStan\Rules\Rule;
+use PHPStan\Testing\RuleTestCase;
+
+/**
+ * @extends RuleTestCase<InvalidCallablePropertyTypeRule>
+ */
+class InvalidCallablePropertyTypeRuleTest extends RuleTestCase
+{
+
+	protected function getRule(): Rule
+	{
+		return new InvalidCallablePropertyTypeRule();
+	}
+
+	public function testRule(): void
+	{
+		$this->analyse([__DIR__ . '/data/invalid-callable-property-type.php'], [
+			[
+				'Property InvalidCallablePropertyType\HelloWorld::$a cannot have callable in its type declaration.',
+				9,
+			],
+			[
+				'Property InvalidCallablePropertyType\HelloWorld::$b cannot have callable in its type declaration.',
+				12,
+			],
+			[
+				'Property InvalidCallablePropertyType\HelloWorld::$c cannot have callable in its type declaration.',
+				15,
+			],
+			[
+				'Property InvalidCallablePropertyType\HelloWorld::$callback cannot have callable in its type declaration.',
+				23,
+			],
+		]);
+	}
+
+}

tests/PHPStan/Rules/Properties/data/invalid-callable-property-type.php

@@ -0,0 +1,31 @@
+<?php declare(strict_types = 1);
+
+namespace InvalidCallablePropertyType;
+
+class HelloWorld
+{
+
+	/** @var callable(): void */
+	public callable $a;
+
+	/** @var callable(): void|null */
+	public ?callable $b;
+
+	/** @var callable(): void|string */
+	public callable|string $c;
+
+    /**
+     * @param \Closure(): void $closure
+	 * @param callable(): void $callback
+     */
+    public function __construct(
+		\Closure $closure,
+		public callable $callback
+	)
+	{
+        $this->a = $closure;
+        $this->b = $closure;
+        $this->c = $closure;
+    }
+
+}