fix(php): 解决字符串连接操作符的void类型检查和引用参数处理问题

- 在parseBinaryOpConcat方法中添加了对左右操作数的类型检查，防止void类型的连接操作
- 为concat操作添加了专门的符号函数php::concat
- 修复了引用参数传递时的变量类型验证逻辑
- 更新了常量定义方法的返回类型从string改为void
- 修正了预处理器中函数声明的换行符处理
- 将Iterator方法调用从exec改为call以统一接口调用方式
- 添加了concat_void.php示例文件用于测试void类型连接错误
- 新增了ref相关的测试用例文件

examples/error/concat_void.php

@@ -0,0 +1,11 @@
+<?php
+function foo(): void
+{
+    var_dump(__FUNCTION__);
+}
+
+function main()
+{
+    $s = foo() . "\n";
+    echo $s;
+}

src/Php/CompilerBase.php

@@ -2074,10 +2074,15 @@ class CompilerBase extends \PhpAot\Core\Translator
 
     protected function parseBinaryOpConcat(Expr\BinaryOp\Concat $expr): string
     {
-        $left  = $this->parseIdentifier($expr->left);
+        $left = $this->parseIdentifier($expr->left);
         $right = $this->parseIdentifier($expr->right);
 
-        return 'php::concat(' . $left . ', ' . $right . ')';
+        $leftType = $this->detectTypeOfExpr($expr->left);
+        $rightType = $this->detectTypeOfExpr($expr->right);
+        if ($leftType === self::TYPE_VOID or $rightType === self::TYPE_VOID) {
+            $this->fatalError($expr, 'Cannot concat void');
+        }
+        return Symbol::concat() . '(' . $this->convertStringExpr($left) . ', ' . $this->convertStringExpr($right) . ')';
     }
 
     protected function parseFor(Node\Stmt\For_ $v): string
@@ -2879,7 +2884,7 @@ class CompilerBase extends \PhpAot\Core\Translator
     {
         $expr = $this->parseExpr($expr->expr);
 
-        return '!' . $expr;
+        return '!(' . $expr . ')';
     }
 
     protected function parseWhile(Node\Stmt\While_ $v): string
@@ -3305,6 +3310,15 @@ class CompilerBase extends \PhpAot\Core\Translator
         $type = $this->detectTypeOfExpr($arg->value);
 
         if ($argInfo->byRef) {
+            if ($this->isVarExpr($arg->value)) {
+                $var = $this->parseVariable($arg->value);
+                // 若参数是引用类型，可以传入未定义变量，将立即创建变量作为引用
+                if (!$this->hasLocalVar($var)) {
+                    $this->addLocalVar($var, self::TYPE_VAR);
+                } elseif ($this->getVarType($var) != self::TYPE_REF) {
+                    $this->fatalError($arg, "Argument `{$argInfo->name}` must be a reference, `{$type}` given");
+                }
+            }
             return $this->convertToRef($arg->value);
         }
 
@@ -4407,7 +4421,7 @@ class CompilerBase extends \PhpAot\Core\Translator
         return $flags;
     }
 
-    protected function parseConstDef(mixed $v2): string
+    protected function parseConstDef(mixed $v2): void
     {
         foreach ($v2->consts as $const) {
             $name  = $this->parseIdentifier($const->name);
@@ -4417,8 +4431,6 @@ class CompilerBase extends \PhpAot\Core\Translator
             }
             $this->addConstant($name, $value);
         }
-
-        return '';
     }
 
     protected function addConstant(string $name, string $value): void

src/Php/Preprocessor.php

@@ -129,7 +129,7 @@ class Preprocessor extends CompilerBase
                     $this->prepareClass($v);
                     break;
                 case 'Stmt_Function':
-                    $this->prepareFunction($v) . PHP_EOL;
+                    $this->prepareFunction($v);
                     break;
                 case 'Stmt_Use':
                     $this->parseUse($v);
@@ -202,7 +202,7 @@ class Preprocessor extends CompilerBase
                     $this->prepareClass($v2);
                     break;
                 case 'Stmt_Function':
-                    $this->prepareFunction($v2) . PHP_EOL;
+                    $this->prepareFunction($v2);
                     break;
                 case 'Stmt_Use':
                     $this->parseUse($v2);
@@ -579,7 +579,7 @@ class Preprocessor extends CompilerBase
             if ($this->classDef->hasMethod($name)) {
                 $this->fatalError($v, "Duplicate method `{$this->method}`");
             }
-            $this->prepareFunction($v) . PHP_EOL;
+            $this->prepareFunction($v);
             $this->checkRequiredArgNum($name, $this->methodDef, $v);
             $this->classDef->addMethod($this->methodDef);
         } else {

src/Php/Symbol.php

@@ -25,6 +25,11 @@ class Symbol
         return 'php::instanceOf';
     }
 
+    public static function concat(): string
+    {
+        return 'php::concat';
+    }
+
     public static function getCalledCe(): string
     {
         return CompilerBase::PREFIX . 'get_called_ce(this_)';

src/Php/Translator.php

@@ -848,10 +848,10 @@ class Translator extends Preprocessor
                     $cppCode .= $this->parseFunction($v) . PHP_EOL;
                     break;
                 case 'Stmt_Const':
-                    $this->parseConstDef($v) . PHP_EOL;
+                    $this->parseConstDef($v);
                     break;
                 case 'Stmt_Interface':
-                    $this->parseInterface($v) . PHP_EOL;
+                    $this->parseInterface($v);
                     break;
                 case 'Stmt_Nop':
                     break;
@@ -985,7 +985,7 @@ class Translator extends Preprocessor
                     $code .= $this->parseUse($v2) . PHP_EOL;
                     break;
                 case 'Stmt_Interface':
-                    $code .= $this->parseInterface($v2) . PHP_EOL;
+                    $this->parseInterface($v2);
                     break;
                 default:
                     abort($v2);
@@ -1471,25 +1471,25 @@ class Translator extends Preprocessor
         $this->addLocalVar($tmpArrayVar, self::TYPE_ARRAY);
 
         $code = 'if (' . $obj . '.instanceOf("IteratorAggregate")) {' . PHP_EOL;
-        $code .= $this->getIndent() . $tmpVar . ' = ' . $obj . '.exec("getIterator");' . PHP_EOL . '}' . PHP_EOL;
+        $code .= $this->getIndent() . $tmpVar . ' = ' . $obj . '.call("getIterator");' . PHP_EOL . '}' . PHP_EOL;
         $code .= 'else if (' . $obj . '.instanceOf("Iterator")) {' . PHP_EOL;
         $code .= $this->getIndent() . $tmpVar . ' = ' . $obj . ';' . PHP_EOL . '}' . PHP_EOL;
 
         $code .= 'if (' . $tmpVar . ') {' . PHP_EOL;
 
         $this->indentLevel++;
-        $code .= $this->getIndent() . $tmpVar . '.exec("rewind");' . PHP_EOL;
-        $code .= $this->getIndent() . 'for (;' . $tmpVar . '.exec("valid");  ' . $tmpVar . '.exec("next")) {' . PHP_EOL;
+        $code .= $this->getIndent() . $tmpVar . '.call("rewind");' . PHP_EOL;
+        $code .= $this->getIndent() . 'for (;' . $tmpVar . '.call("valid");  ' . $tmpVar . '.call("next")) {' . PHP_EOL;
         $this->indentLevel++;
 
         $valueVar = $this->parseIdentifier($node->valueVar);
         $this->checkVar($node, $valueVar);
 
-        $code .= $this->getIndent() . ' ' . $valueVar . ' = ' . $tmpVar . '.exec("current");' . PHP_EOL;
+        $code .= $this->getIndent() . ' ' . $valueVar . ' = ' . $tmpVar . '.call("current");' . PHP_EOL;
         if ($node->keyVar) {
             $keyVar = $this->parseIdentifier($node->keyVar);
             $this->checkVar($node, $keyVar);
-            $code .= $this->getIndent() . ' ' . $keyVar . ' = ' . $tmpVar . '.exec("key");' . PHP_EOL;
+            $code .= $this->getIndent() . ' ' . $keyVar . ' = ' . $tmpVar . '.call("key");' . PHP_EOL;
         }
         $code .= $this->parseStmts($node->stmts);
         $code .= '}' . PHP_EOL;

tests/aot/ref/006.phpt

@@ -0,0 +1,27 @@
+--TEST--
+ref
+--FILE--
+<?php
+class Request {
+    public function bar() {
+        $this->foo('hello', $class);
+        $this->dump($class);
+    }
+
+    public function foo($name, ?string &$class) {
+        $class = __CLASS__;
+    }
+
+    public function dump(string $class) {
+        var_dump($class);
+    }
+}
+
+function main()
+{
+    $req = new Request;
+    $req->bar();
+}
+?>
+--EXPECT--
+string(7) "Request"