feat(parser): add readonly property support with hoisting restrictions

- Add readonly flag to PropertyDef entity
- Implement readonly check in property hoisting logic
- Prevent hoisting of readonly properties in SsaPropOptimizer
- Update canHoist methods to accept PropertyDef parameter
- Add test case for readonly cross-class property access
- Document readonly property restriction in hoisting rules

src/Entity/PropertyDef.php

@@ -22,6 +22,7 @@ class PropertyDef
     public array $typeCheck = [];
     public string $typeStr = '';
     public bool $promoted = false;
+    public bool $readonly = false;
     public ?string $getter = null;
     public ?string $setter = null;
 
@@ -54,6 +55,11 @@ class PropertyDef
         return $this->flags & Modifiers::STATIC;
     }
 
+    public function isReadonly(): bool
+    {
+        return $this->readonly;
+    }
+
     public function isPrivateSet(): bool
     {
         return (bool) ($this->flags & Modifiers::PRIVATE_SET);

src/Optimizer/SsaPropOptimizer.php

@@ -17,6 +17,7 @@
  *  6. No func(&$o->prop) (property passed by reference)
  *  7. Object is not exposed to dynamic user code before later property access
  *  8. First access is not inside a loop or nested block scope
+ *  9. Property is not readonly (including properties of a readonly class)
  *
  * Direct unset($o->prop) is not dangerous: the object handlers reset/reject the
  * unset path, so a hoisted reference is not invalidated by direct unset alone.
@@ -24,6 +25,7 @@
 
 namespace TypePhp\Optimizer;
 
+use TypePhp\Entity\PropertyDef;
 use TypePhp\Type;
 
 use TypePhp\Analysis\SsaBuilder;
@@ -754,24 +756,31 @@ trait SsaPropOptimizer
         return isset($this->context->stableObjects[$objName]);
     }
 
-    public function canHoistStableObjectProp(string $objName, string $propName): bool
+    public function canHoistStableObjectProp(string $objName, string $propName, PropertyDef $property): bool
     {
         if (!$this->isStableObject($objName)) {
             return false;
         }
-        return $this->canHoistObjectPropBySafety($objName, $propName);
+        return $this->canHoistObjectPropBySafety($objName, $propName, $property);
     }
 
-    public function canHoistObjectProp(string $objName, string $propName): bool
+    public function canHoistObjectProp(string $objName, string $propName, PropertyDef $property): bool
     {
         if ($objName !== 'this_' && !$this->isStableObject($objName)) {
             return false;
         }
-        return $this->canHoistObjectPropBySafety($objName, $propName);
+        return $this->canHoistObjectPropBySafety($objName, $propName, $property);
     }
 
-    protected function canHoistObjectPropBySafety(string $objName, string $propName): bool
+    protected function canHoistObjectPropBySafety(
+        string $objName,
+        string $propName,
+        PropertyDef $property,
+    ): bool
     {
+        if ($property->isReadonly()) {
+            return false;
+        }
         $unsafeProps = $this->context->unsafeObjectProps[$objName] ?? [];
         return !isset($unsafeProps['*']) && !isset($unsafeProps[$propName]);
     }

src/Parser/PropertyAccessTrait.php

@@ -898,7 +898,7 @@ trait PropertyAccessTrait
 
         $propVar = $this->getObjectPropVarName($objectVar, $propName);
         if ($objectVar === 'this_') {
-            if (!$this->canHoistObjectProp($objectVar, $propName)) {
+            if (!$this->canHoistObjectProp($objectVar, $propName, $def)) {
                 return null;
             }
             $this->registerHoistedObjectPropVar($propVar, $def->type, $getter);
@@ -907,7 +907,7 @@ trait PropertyAccessTrait
             return $propVar;
         }
 
-        if (!$this->canHoistStableObjectProp($objectVar, $propName)) {
+        if (!$this->canHoistStableObjectProp($objectVar, $propName, $def)) {
             return null;
         }
 

src/Preprocessor.php

@@ -710,6 +710,7 @@ class Preprocessor extends CompilerBase
         }
 
         $propDef = new PropertyDef($name, $flags, $type, $default, $nullable);
+        $propDef->readonly = (bool) (($flags | $this->classDef->flags) & Modifiers::READONLY);
         $propDef->class = $class;
         $propDef->arrayInitPlan = $arrayInitPlan;
         $propDef->promoted = $promoted;

tests/aot/object_property/readonly-cross-class-direct.phpt

@@ -0,0 +1,95 @@
+--TEST--
+Readonly native properties remain initialized when read across classes
+--FILE--
+<?php
+
+use native_types;
+
+class ReadonlyDimensions
+{
+    public readonly int $x;
+    public readonly int $y;
+    public readonly float $scale;
+
+    public function __construct(int $x, int $y, float $scale)
+    {
+        $this->x = $x;
+        $this->y = $y;
+        $this->scale = $scale;
+    }
+
+    public function values(): array
+    {
+        return [$this->x, $this->y, $this->scale];
+    }
+}
+
+class MutableDimensions
+{
+    public int $x;
+
+    public function __construct(int $x)
+    {
+        $this->x = $x;
+    }
+}
+
+readonly class ReadonlyClassDimensions
+{
+    public int $x;
+
+    public function __construct(int $x)
+    {
+        $this->x = $x;
+    }
+}
+
+class DimensionsReader
+{
+    public static function readonlyValues(ReadonlyDimensions $value): array
+    {
+        return [$value->x, $value->y, $value->scale];
+    }
+
+    public static function mutableValue(MutableDimensions $value): int
+    {
+        return $value->x;
+    }
+
+    public static function readonlyClassValue(ReadonlyClassDimensions $value): int
+    {
+        return $value->x;
+    }
+}
+
+function main(): void
+{
+    $readonly = new ReadonlyDimensions(10, 20, 1.5);
+    $mutable = new MutableDimensions(30);
+    $readonlyClass = new ReadonlyClassDimensions(40);
+
+    var_dump(DimensionsReader::readonlyValues($readonly));
+    var_dump($readonly->values());
+    var_dump(DimensionsReader::mutableValue($mutable));
+    var_dump(DimensionsReader::readonlyClassValue($readonlyClass));
+}
+?>
+--EXPECT--
+array(3) {
+  [0]=>
+  int(10)
+  [1]=>
+  int(20)
+  [2]=>
+  float(1.5)
+}
+array(3) {
+  [0]=>
+  int(10)
+  [1]=>
+  int(20)
+  [2]=>
+  float(1.5)
+}
+int(30)
+int(40)