Merge pull request 'fix(compiler): 修复unset引用变量后对变量的操作' (#14) from fix-unset-ref-coalesce into master

Reviewed-on: #14

src/Php/CompilerBase.php

@@ -5977,8 +5977,12 @@ class CompilerBase extends \PhpAot\Core\Translator implements PropertyAccessCont
         $fn = $this->getChainedFunc($op);
         $expr = $node;
         if ($this->isVarExpr($expr)) {
+            if (!$getValue) {
                 return $fn . '(' . $this->parseExpr($expr) . ')';
             }
+            // $getValue is true: fall through to use the chain+result mechanism,
+            // which ensures the result type is TYPE_VAR (compatible with ternaries).
+        }
         // 单属性读取（非链式）
         if ($this->isPropertyFetch($expr) and $this->isVarExpr($expr->var) and $this->isIdExpr($expr->name)) {
             $prop = $this->parsePropertyFetch($expr);

tests/aot/coalesce/unset-ref-coalesce.phpt

@@ -0,0 +1,96 @@
+--TEST--
+Null coalescing (??) on unset reference variable
+--FILE--
+<?php
+
+function main()
+{
+    // Test 1: unset reference variable then ?? with int
+    $a = 1;
+    $b = &$a;
+    $b = 2;
+    var_dump($a, $b);
+    unset($b);
+    var_dump($a);
+    var_dump(isset($b));
+    var_dump($b ?? 123);
+
+    // Test 2: unset reference variable then ?? with string
+    $c = 'hello';
+    $d = &$c;
+    $d = 'world';
+    var_dump($c, $d);
+    unset($d);
+    var_dump($c);
+    var_dump(isset($d));
+    var_dump($d ?? 'default');
+
+    // Test 3: ?? on reference without unset (should return value)
+    $e = 42;
+    $f = &$e;
+    var_dump($f ?? 999);
+
+    // Test 4: chained ?? with unset reference
+    $g = 'first';
+    $h = &$g;
+    unset($h);
+    var_dump($h ?? null ?? 'fallback');
+
+    // Test 5: ??= on unset reference (assign coalesce)
+    $i = 10;
+    $j = &$i;
+    $j = 20;
+    unset($j);
+    $j ??= 30;
+    var_dump($j);
+    var_dump($i);
+
+    // Test 6: reference reassignment after unset
+    $k = 100;
+    $l = &$k;
+    unset($l);
+    var_dump($l ?? 200);
+    $l = 300;
+    var_dump($l);
+    var_dump($k);
+
+    // Test 7: normal variable unset + ??
+    $m = 50;
+    unset($m);
+    var_dump($m ?? 777);
+
+    // Test 8: isset after unset of reference
+    $n = 'test';
+    $o = &$n;
+    unset($o);
+    var_dump(isset($o));
+
+    // Test 9: elvis (?:) on unset reference
+    $p = 5;
+    $q = &$p;
+    $q = 6;
+    unset($q);
+    var_dump($q ?: -1);
+}
+?>
+--EXPECT--
+int(2)
+int(2)
+int(2)
+bool(false)
+int(123)
+string(5) "world"
+string(5) "world"
+string(5) "world"
+bool(false)
+string(7) "default"
+int(42)
+string(8) "fallback"
+int(30)
+int(20)
+int(200)
+int(300)
+int(100)
+int(777)
+bool(false)
+int(-1)