fix(php): 修复箭头函数变量作用域和二元运算符解析问题

- 添加箭头函数基本功能测试用例验证闭包行为
- 修复二元运算符解析时变量存在性检查逻辑
- 解决全局变量在箭头函数中的访问问题
- 修复数组解包空数组导致断言失败的bug
- 改进变量名转义和局部变量检测机制

src/Php/CompilerBase.php

@@ -1532,12 +1532,15 @@ class CompilerBase extends \PhpAot\Core\Translator
         return $this->parseIdentifier($expr);
     }
 
-    protected function parseBinaryOp($left, $right, $op): string
+    protected function parseBinaryOp(NodeAbstract $left, NodeAbstract $right, string $op): string
     {
         // 运算逻辑，优先转为数字
         $leftExpr  = $this->parseNumericIdentifier($left);
         $rightExpr = $this->parseNumericIdentifier($right);
 
+        $this->checkVarMustExist($left, $leftExpr);
+        $this->checkVarMustExist($right, $rightExpr);
+
         $leftType  = $this->detectExprType($left);
         $rightType = $this->detectExprType($right);
 
@@ -4576,13 +4579,14 @@ class CompilerBase extends \PhpAot\Core\Translator
         }
 
         foreach ($vars as $var) {
-            if ($var->name === 'this'
-                or !$this->hasLocalVar($var->name)
+            $varName = $this->escapeVarName($this->parseVariable($var));
+            if ($varName === 'this'
+                or !$this->hasLocalVar($varName)
                 or isset($params[$var->name])
-                or isset($uses[$var->name])) {
+                or isset($uses[$varName])) {
                 continue;
             }
-            $uses[$var->name] = new Node\ClosureUse($var);
+            $uses[$varName] = new Node\ClosureUse($var);
         }
         $uses = array_values($uses);
 

tests/zend/array_unpack/gh19303.phpt

@@ -0,0 +1,11 @@
+--TEST--
+GH-19303 (Unpacking empty packed array into uninitialized array causes assertion failure)
+--FILE--
+<?php
+$a = [0];
+unset($a[0]);
+var_dump([...$a]);
+?>
+--EXPECT--
+array(0) {
+}

tests/zend/arrow_functions/001.phpt

@@ -0,0 +1,45 @@
+--TEST--
+Basic arrow function functionality check
+--FILE--
+<?php
+
+$foo = fn() => 1;
+var_dump($foo());
+
+$foo = fn($x) => $x;
+var_dump($foo(2));
+
+$foo = fn($x, $y) => $x + $y;
+var_dump($foo(1, 2));
+
+// Closing over $var
+$var = 4;
+$foo = fn() => $var;
+var_dump($foo());
+
+// Not closing over $var, it's a parameter
+$foo = fn($var) => $var;
+var_dump($foo(5));
+
+// Close over $var by-value, not by-reference
+$var = 5;
+$foo = fn() => ++$var;
+var_dump($foo());
+var_dump($var);
+
+// Nested arrow functions closing over variable
+$var = 6;
+var_dump((fn() => fn() => $var)()());
+var_dump((fn() => function() use($var) { return $var; })()());
+
+?>
+--EXPECT--
+int(1)
+int(2)
+int(3)
+int(4)
+int(5)
+int(6)
+int(5)
+int(6)
+int(6)

tests/zend/arrow_functions/004.phpt

@@ -0,0 +1,13 @@
+--TEST--
+Auto-globals in arrow functions
+--FILE--
+<?php
+function main() {
+    global $a;
+    $a = 123;
+    $fn = fn() => $GLOBALS['a'];
+    var_dump($fn());
+}
+?>
+--EXPECT--
+int(123)