Support property type promotion ref #4089

src/Psalm/Internal/PhpVisitor/ReflectorVisitor.php

@@ -1854,6 +1854,8 @@ class ReflectorVisitor extends PhpParser\NodeVisitorAbstract implements PhpParse
         $fq_classlike_name = null;
         $is_functionlike_override = false;
 
+        $method_name_lc = null;
+
         if ($fake_method && $stmt instanceof PhpParser\Node\Stmt\ClassMethod) {
             $cased_function_id = '@method ' . $stmt->name->name;
 
@@ -2359,6 +2361,61 @@ class ReflectorVisitor extends PhpParser\NodeVisitorAbstract implements PhpParse
             }
         }
 
+        if ($class_storage && $method_name_lc === '__construct') {
+            foreach ($stmt->getParams() as $param) {
+                if (!$param->flags || !$param->var instanceof PhpParser\Node\Expr\Variable) {
+                    continue;
+                }
+
+                $param_storage = null;
+
+                foreach ($storage->params as $param_storage) {
+                    if ($param_storage->name === $param->var->name) {
+                        break;
+                    }
+                }
+
+                if (!$param_storage) {
+                    continue;
+                }
+
+                $property_storage = $class_storage->properties[$param_storage->name] = new PropertyStorage();
+                $property_storage->is_static = false;
+                $property_storage->type = $param_storage->type;
+                $property_storage->signature_type = $param_storage->signature_type;
+                $property_storage->signature_type_location = $param_storage->signature_type_location;
+                $property_storage->type_location = $param_storage->type_location;
+                $property_storage->location = $param_storage->location;
+                $property_storage->stmt_location = new CodeLocation($this->file_scanner, $param);
+                $property_storage->has_default = $param->default ? true : false;
+
+                $property_id = $fq_classlike_name . '::$' . $param_storage->name;
+
+                switch ($param->flags) {
+                    case \PhpParser\Node\Stmt\Class_::MODIFIER_PUBLIC:
+                        $property_storage->visibility = ClassLikeAnalyzer::VISIBILITY_PUBLIC;
+                        $class_storage->inheritable_property_ids[$param_storage->name] = $property_id;
+                        break;
+
+                    case \PhpParser\Node\Stmt\Class_::MODIFIER_PROTECTED:
+                        $property_storage->visibility = ClassLikeAnalyzer::VISIBILITY_PROTECTED;
+                        $class_storage->inheritable_property_ids[$param_storage->name] = $property_id;
+                        break;
+
+                    case \PhpParser\Node\Stmt\Class_::MODIFIER_PRIVATE:
+                        $property_storage->visibility = ClassLikeAnalyzer::VISIBILITY_PRIVATE;
+                        break;
+                }
+
+                $fq_classlike_name = $this->fq_classlike_names[count($this->fq_classlike_names) - 1];
+
+                $property_id = $fq_classlike_name . '::$' . $param_storage->name;
+
+                $class_storage->declaring_property_ids[$param_storage->name] = $fq_classlike_name;
+                $class_storage->appearing_property_ids[$param_storage->name] = $property_id;
+            }
+        }
+
         if ($stmt instanceof PhpParser\Node\Stmt\ClassMethod
             && $stmt->name->name === '__construct'
             && $class_storage

tests/PropertyTypeTest.php

@@ -2074,6 +2074,34 @@ class PropertyTypeTest extends TestCase
                         }
                     }'
             ],
+            'promotedPublicProperty' => [
+                '<?php
+                    class A {
+                        public function __construct(public int $foo = 5) {}
+                    }
+
+                    echo (new A)->foo;'
+            ],
+            'promotedProtectedProperty' => [
+                '<?php
+                    class A {
+                        public function __construct(protected int $foo = 5) {}
+                    }
+
+                    class AChild extends A {
+                        public function bar() : int {
+                            return $this->foo;
+                        }
+                    }'
+            ],
+            'setPublicProperty' => [
+                '<?php
+                    class A {
+                        public function __construct(public int $foo) {
+                            $this->foo = 5;
+                        }
+                    }'
+            ],
         ];
     }
 
@@ -3214,6 +3242,22 @@ class PropertyTypeTest extends TestCase
                     }',
                 'error_message' => 'MissingPropertyType',
             ],
+            'promotedPrivateProperty' => [
+                '<?php
+                    class A {
+                        public function __construct(private int $foo = 5) {}
+                    }
+
+                    echo (new A)->foo;',
+                'error_message' => 'InaccessibleProperty',
+            ],
+            'promotedPublicPropertyWithoutSet' => [
+                '<?php
+                    class A {
+                        public function __construct(public int $foo) {}
+                    }',
+                'error_message' => 'PropertyNotSetInConstructor'
+            ],
         ];
     }
 }