Rules for checking direct calls to __construct()

conf/bleedingEdge.neon

@@ -8,3 +8,4 @@ parameters:
 		arrayUnpacking: true
 		nodeConnectingVisitorCompatibility: false
 		disableRuntimeReflectionProvider: true
+		illegalConstructorMethodCall: true

conf/config.level2.neon

@@ -40,6 +40,12 @@ rules:
 	- PHPStan\Rules\PhpDoc\WrongVariableNameInVarTagRule
 	- PHPStan\Rules\Properties\AccessPrivatePropertyThroughStaticRule
 
+conditionalTags:
+	PHPStan\Rules\Methods\IllegalConstructorMethodCallRule:
+		phpstan.rules.rule: %featureToggles.illegalConstructorMethodCall%
+	PHPStan\Rules\Methods\IllegalConstructorStaticCallRule:
+		phpstan.rules.rule: %featureToggles.illegalConstructorMethodCall%
+
 services:
 	-
 		class: PHPStan\Rules\Classes\MixinRule
@@ -53,6 +59,10 @@ services:
 			reportMaybes: %reportMaybes%
 		tags:
 			- phpstan.rules.rule
+	-
+		class: PHPStan\Rules\Methods\IllegalConstructorMethodCallRule
+	-
+		class: PHPStan\Rules\Methods\IllegalConstructorStaticCallRule
 	-
 		class: PHPStan\Rules\PhpDoc\InvalidPhpDocVarTagTypeRule
 		arguments:

conf/config.neon

@@ -32,6 +32,7 @@ parameters:
 		arrayFilter: false
 		arrayUnpacking: false
 		nodeConnectingVisitorCompatibility: true
+		illegalConstructorMethodCall: false
 	fileExtensions:
 		- php
 	checkAdvancedIsset: false
@@ -219,6 +220,7 @@ parametersSchema:
 		arrayFilter: bool(),
 		arrayUnpacking: bool(),
 		nodeConnectingVisitorCompatibility: bool(),
+		illegalConstructorMethodCall: bool(),
 	])
 	fileExtensions: listOf(string())
 	checkAdvancedIsset: bool()

src/Rules/Methods/IllegalConstructorMethodCallRule.php

@@ -0,0 +1,33 @@
+<?php declare(strict_types = 1);
+
+namespace PHPStan\Rules\Methods;
+
+use PhpParser\Node;
+use PHPStan\Analyser\Scope;
+use PHPStan\Rules\Rule;
+use PHPStan\Rules\RuleErrorBuilder;
+
+/**
+ * @implements Rule<Node\Expr\MethodCall>
+ */
+class IllegalConstructorMethodCallRule implements Rule
+{
+
+	public function getNodeType(): string
+	{
+		return Node\Expr\MethodCall::class;
+	}
+
+	public function processNode(Node $node, Scope $scope): array
+	{
+		if (!$node->name instanceof Node\Identifier || $node->name->toLowerString() !== '__construct') {
+			return [];
+		}
+
+		return [
+			RuleErrorBuilder::message('Call to __construct() on an existing object is not allowed.')
+				->build(),
+		];
+	}
+
+}

src/Rules/Methods/IllegalConstructorStaticCallRule.php

@@ -0,0 +1,58 @@
+<?php declare(strict_types = 1);
+
+namespace PHPStan\Rules\Methods;
+
+use PhpParser\Node;
+use PHPStan\Analyser\Scope;
+use PHPStan\Rules\Rule;
+use PHPStan\Rules\RuleErrorBuilder;
+
+/**
+ * @implements Rule<Node\Expr\StaticCall>
+ */
+class IllegalConstructorStaticCallRule implements Rule
+{
+
+	public function getNodeType(): string
+	{
+		return Node\Expr\StaticCall::class;
+	}
+
+	public function processNode(Node $node, Scope $scope): array
+	{
+		if (!$node->name instanceof Node\Identifier || $node->name->toLowerString() !== '__construct') {
+			return [];
+		}
+
+		if ($this->isCollectCallingConstructor($node, $scope)) {
+			return [];
+		}
+
+		return [
+			RuleErrorBuilder::message('Static call to __construct() is only allowed on a parent class in the constructor.')
+				->build(),
+		];
+	}
+
+	private function isCollectCallingConstructor(Node $node, Scope $scope): bool
+	{
+		if (!$node instanceof Node\Expr\StaticCall) {
+			return true;
+		}
+		// __construct should be called from inside constructor
+		if ($scope->getFunction() !== null && $scope->getFunction()->getName() !== '__construct') {
+			return false;
+		}
+
+		if (!$scope->isInClass()) {
+			return false;
+		}
+
+		if (!$node->class instanceof Node\Name) {
+			return false;
+		}
+
+		return $node->class->toLowerString() === 'parent';
+	}
+
+}

tests/PHPStan/Rules/Methods/IllegalConstructorMethodCallRuleTest.php

@@ -0,0 +1,37 @@
+<?php declare(strict_types = 1);
+
+namespace PHPStan\Rules\Methods;
+
+use PHPStan\Rules\Rule;
+use PHPStan\Testing\RuleTestCase;
+
+/**
+ * @extends RuleTestCase<IllegalConstructorMethodCallRule>
+ */
+class IllegalConstructorMethodCallRuleTest extends RuleTestCase
+{
+
+	protected function getRule(): Rule
+	{
+		return new IllegalConstructorMethodCallRule();
+	}
+
+	public function testMethods(): void
+	{
+		$this->analyse([__DIR__ . '/data/illegal-constructor-call-rule-test.php'], [
+			[
+				'Call to __construct() on an existing object is not allowed.',
+				13,
+			],
+			[
+				'Call to __construct() on an existing object is not allowed.',
+				18,
+			],
+			[
+				'Call to __construct() on an existing object is not allowed.',
+				60,
+			],
+		]);
+	}
+
+}

tests/PHPStan/Rules/Methods/IllegalConstructorStaticCallRuleTest.php

@@ -0,0 +1,45 @@
+<?php declare(strict_types = 1);
+
+namespace PHPStan\Rules\Methods;
+
+use PHPStan\Rules\Rule;
+use PHPStan\Testing\RuleTestCase;
+
+/**
+ * @extends RuleTestCase<IllegalConstructorStaticCallRule>
+ */
+class IllegalConstructorStaticCallRuleTest extends RuleTestCase
+{
+
+	protected function getRule(): Rule
+	{
+		return new IllegalConstructorStaticCallRule();
+	}
+
+	public function testMethods(): void
+	{
+		$this->analyse([__DIR__ . '/data/illegal-constructor-call-rule-test.php'], [
+			[
+				'Static call to __construct() is only allowed on a parent class in the constructor.',
+				31,
+			],
+			[
+				'Static call to __construct() is only allowed on a parent class in the constructor.',
+				43,
+			],
+			[
+				'Static call to __construct() is only allowed on a parent class in the constructor.',
+				44,
+			],
+			[
+				'Static call to __construct() is only allowed on a parent class in the constructor.',
+				49,
+			],
+			[
+				'Static call to __construct() is only allowed on a parent class in the constructor.',
+				50,
+			],
+		]);
+	}
+
+}

tests/PHPStan/Rules/Methods/data/illegal-constructor-call-rule-test.php

@@ -0,0 +1,63 @@
+<?php
+
+namespace IllegalConstructorMethodCall;
+
+class ExtendedDateTimeWithMethodCall extends \DateTimeImmutable
+{
+	public function __construct(string $datetime = "now", ?\DateTimeZone $timezone = null)
+	{
+		// Avoid infinite loop
+		if (count(debug_backtrace()) > 1) {
+			return;
+		}
+		$this->__construct($datetime, $timezone);
+	}
+
+	public function mutate(string $datetime = "now", ?\DateTimeZone $timezone = null): void
+	{
+		$this->__construct($datetime, $timezone);
+	}
+}
+
+class ExtendedDateTimeWithParentCall extends \DateTimeImmutable
+{
+	public function __construct(string $datetime = "now", ?\DateTimeZone $timezone = null)
+	{
+		parent::__construct($datetime, $timezone);
+	}
+
+	public function mutate(string $datetime = "now", ?\DateTimeZone $timezone = null): void
+	{
+		parent::__construct($datetime, $timezone);
+	}
+}
+
+class ExtendedDateTimeWithSelfCall extends \DateTimeImmutable
+{
+	public function __construct(string $datetime = "now", ?\DateTimeZone $timezone = null)
+	{
+		// Avoid infinite loop
+		if (count(debug_backtrace()) > 1) {
+			return;
+		}
+		self::__construct($datetime, $timezone);
+		ExtendedDateTimeWithSelfCall::__construct($datetime, $timezone);
+	}
+
+	public function mutate(string $datetime = "now", ?\DateTimeZone $timezone = null): void
+	{
+		self::__construct($datetime, $timezone);
+		ExtendedDateTimeWithSelfCall::__construct($datetime, $timezone);
+	}
+}
+
+class Foo
+{
+
+	public function doFoo()
+	{
+		$extendedDateTime = new ExtendedDateTimeWithMethodCall('2022/04/12');
+		$extendedDateTime->__construct('2022/04/13');
+	}
+
+}