Fix phpstan/phpstan#14063: Readonly property modification through clone() is not reported outside allowed scope (#5432)

Co-authored-by: VincentLanglet <9052536+VincentLanglet@users.noreply.github.com>
Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

Author: 3 people

tests/PHPStan/Rules/Properties/AccessPropertiesInAssignRuleTest.php

@@ -207,6 +207,25 @@ public function testBug13123(): void
 		$this->analyse([__DIR__ . '/data/bug-13123.php'], []);
 	}
 
+	#[RequiresPhp('>= 8.5')]
+	public function testBug14063(): void
+	{
+		$this->analyse([__DIR__ . '/data/bug-14063.php'], [
+			[
+				'Assign to protected(set) property Bug14063\Obj::$value.',
+				31,
+			],
+			[
+				'Assign to protected(set) property Bug14063\Obj::$value.',
+				34,
+			],
+			[
+				'Assign to protected(set) property Bug14063\Base::$value.',
+				38,
+			],
+		]);
+	}
+
 	#[RequiresPhp('>= 8.5')]
 	public function testCloneWith(): void
 	{

tests/PHPStan/Rules/Properties/data/bug-14063.php

@@ -0,0 +1,39 @@
+<?php // lint >= 8.5
+
+declare(strict_types = 1);
+
+namespace Bug14063;
+
+final readonly class Obj
+{
+	public function __construct(public string $value) {}
+
+	public function withValue(string $newValue): self
+	{
+		return clone($this, ['value' => $newValue]);
+	}
+}
+
+readonly class Base
+{
+	public function __construct(public string $value) {}
+}
+
+readonly class Child extends Base
+{
+	public function withValue(string $newValue): self
+	{
+		return clone($this, ['value' => $newValue]);
+	}
+}
+
+$obj = new Obj('val');
+$newObj = clone($obj, ['value' => 'newVal']);
+
+function test(Obj $obj): void {
+	clone($obj, ['value' => 'newVal']);
+}
+
+function testBase(Base $base): void {
+	clone($base, ['value' => 'newVal']);
+}