test(compiler): 添加类方法重写顺序测试用例

- 创建 class-method-override-order.php 测试文件，包含子类先于父类定义的场景
- 实现 ClassMethodOverrideTest 类，验证编译器对类方法重写的双向递归处理
- 添加 testChildBeforeParentOverride 方法，测试父子类方法重写关系的正确识别
- 验证父类方法被正确标记为被子类覆盖的状态
- 确保子类方法未被错误标记为已覆盖状态
- 通过反射访问编译器内部的 classMethodOverride 属性进行断言验证

phpunit/code/class-method-override-order.php

@@ -0,0 +1,22 @@
+<?php
+// 子类先于父类定义，测试 classMethodOverride 的双向递归是否正确
+class ChildOverride extends ParentBase {
+    public function bar(): void {
+        echo "Child\n";
+    }
+}
+
+class ParentBase {
+    public function run(): void {
+        $this->bar();
+    }
+
+    public function bar(): void {
+        echo "Parent\n";
+    }
+}
+
+function main(): void {
+    $o = new ChildOverride();
+    $o->run();
+}

phpunit/src/ClassMethodOverrideTest.php

@@ -0,0 +1,28 @@
+<?php
+
+use PhpAot\Php\CompilerTest;
+
+class ClassMethodOverrideTest extends \BaseTest
+{
+    public function testChildBeforeParentOverride(): void
+    {
+        $compiler = CompilerTest::create(ROOT_PATH);
+        $testFile = __DIR__ . '/../code/class-method-override-order.php';
+        $compiler->addFiles([$testFile]);
+        $compiler->prepareFile($testFile);
+
+        $ref = new ReflectionClass($compiler);
+        $prop = $ref->getProperty('classMethodOverride');
+        $classMethodOverride = $prop->getValue($compiler);
+
+        $parentMethodLower = strtolower('ParentBase::bar');
+        $childMethodLower = strtolower('ChildOverride::bar');
+
+        $this->assertArrayHasKey($parentMethodLower, $classMethodOverride, 'ParentBase::bar should be registered');
+        $this->assertArrayHasKey($childMethodLower, $classMethodOverride, 'ChildOverride::bar should be registered');
+        // 父类方法应被标记为已被子类覆盖
+        $this->assertTrue($classMethodOverride[$parentMethodLower], 'ParentBase::bar should be marked as overridden by child');
+        // 子类方法未被覆盖
+        $this->assertFalse($classMethodOverride[$childMethodLower], 'ChildOverride::bar should not be marked as overridden');
+    }
+}