feature #34557 [PropertyInfo] Add support for typed properties (PHP 7…

….4) (dunglas)

This PR was squashed before being merged into the 5.1-dev branch (closes #34557).

Discussion
----------

[PropertyInfo] Add support for typed properties (PHP 7.4)

| Q             | A
| ------------- | ---
| Branch?       | master
| Bug fix?      | no
| New feature?  | yes
| Deprecations? | no <!-- please update UPGRADE-*.md and src/**/CHANGELOG.md files -->
| Tickets       | n/a <!-- prefix each issue number with "Fix #", if any -->
| License       | MIT
| Doc PR        | n/a

Add support for [typed properties](https://wiki.php.net/rfc/typed_properties_v2), a new feature introduced in PHP 7.4:

```php
class Foo
{
    public Bar $bar;
    private ?bool $nullableBoolProp;
}

$this->extractor->getTypes(Foo::class, 'bar'); // Type[]
$this->extractor->getTypes(Foo::class, 'nullableBoolProp'); // Type[]
```

#SymfonyHackday

Commits
-------

7edfe4f [PropertyInfo] Add support for typed properties (PHP 7.4)

src/Symfony/Component/PropertyInfo/Extractor/ReflectionExtractor.php

@@ -133,6 +133,18 @@ public function getProperties(string $class, array $context = []): ?array
      */
     public function getTypes(string $class, string $property, array $context = []): ?array
     {
+        if (\PHP_VERSION_ID >= 70400) {
+            try {
+                $reflectionProperty = new \ReflectionProperty($class, $property);
+                $type = $reflectionProperty->getType();
+                if (null !== $type) {
+                    return [$this->extractFromReflectionType($type, $reflectionProperty->getDeclaringClass())];
+                }
+            } catch (\ReflectionException $e) {
+                // noop
+            }
+        }
+
         if ($fromMutator = $this->extractFromMutator($class, $property)) {
             return $fromMutator;
         }
@@ -227,7 +239,7 @@ private function extractFromMutator(string $class, string $property): ?array
         if (!$reflectionType = $reflectionParameter->getType()) {
             return null;
         }
-        $type = $this->extractFromReflectionType($reflectionType, $reflectionMethod);
+        $type = $this->extractFromReflectionType($reflectionType, $reflectionMethod->getDeclaringClass());
 
         if (\in_array($prefix, $this->arrayMutatorPrefixes)) {
             $type = new Type(Type::BUILTIN_TYPE_ARRAY, false, null, true, new Type(Type::BUILTIN_TYPE_INT), $type);
@@ -249,7 +261,7 @@ private function extractFromAccessor(string $class, string $property): ?array
         }
 
         if ($reflectionType = $reflectionMethod->getReturnType()) {
-            return [$this->extractFromReflectionType($reflectionType, $reflectionMethod)];
+            return [$this->extractFromReflectionType($reflectionType, $reflectionMethod->getDeclaringClass())];
         }
 
         if (\in_array($prefix, ['is', 'can', 'has'])) {
@@ -284,7 +296,7 @@ private function extractFromConstructor(string $class, string $property): ?array
             }
             $reflectionType = $parameter->getType();
 
-            return $reflectionType ? [$this->extractFromReflectionType($reflectionType, $constructor)] : null;
+            return $reflectionType ? [$this->extractFromReflectionType($reflectionType, $constructor->getDeclaringClass())] : null;
         }
 
         if ($parentClass = $reflectionClass->getParentClass()) {
@@ -313,7 +325,7 @@ private function extractFromDefaultValue(string $class, string $property): ?arra
         return [new Type(static::MAP_TYPES[$type] ?? $type)];
     }
 
-    private function extractFromReflectionType(\ReflectionType $reflectionType, \ReflectionMethod $reflectionMethod): Type
+    private function extractFromReflectionType(\ReflectionType $reflectionType, \ReflectionClass $declaringClass): Type
     {
         $phpTypeOrClass = $reflectionType->getName();
         $nullable = $reflectionType->allowsNull();
@@ -325,18 +337,18 @@ private function extractFromReflectionType(\ReflectionType $reflectionType, \Ref
         } elseif ($reflectionType->isBuiltin()) {
             $type = new Type($phpTypeOrClass, $nullable);
         } else {
-            $type = new Type(Type::BUILTIN_TYPE_OBJECT, $nullable, $this->resolveTypeName($phpTypeOrClass, $reflectionMethod));
+            $type = new Type(Type::BUILTIN_TYPE_OBJECT, $nullable, $this->resolveTypeName($phpTypeOrClass, $declaringClass));
         }
 
         return $type;
     }
 
-    private function resolveTypeName(string $name, \ReflectionMethod $reflectionMethod): string
+    private function resolveTypeName(string $name, \ReflectionClass $declaringClass): string
     {
         if ('self' === $lcName = strtolower($name)) {
-            return $reflectionMethod->getDeclaringClass()->name;
+            return $declaringClass->name;
         }
-        if ('parent' === $lcName && $parent = $reflectionMethod->getDeclaringClass()->getParentClass()) {
+        if ('parent' === $lcName && $parent = $declaringClass->getParentClass()) {
             return $parent->name;
         }
 

src/Symfony/Component/PropertyInfo/Tests/Extractor/ReflectionExtractorTest.php

@@ -19,6 +19,7 @@
 use Symfony\Component\PropertyInfo\Tests\Fixtures\NotInstantiable;
 use Symfony\Component\PropertyInfo\Tests\Fixtures\Php71Dummy;
 use Symfony\Component\PropertyInfo\Tests\Fixtures\Php71DummyExtended2;
+use Symfony\Component\PropertyInfo\Tests\Fixtures\Php74Dummy;
 use Symfony\Component\PropertyInfo\Type;
 
 /**
@@ -365,4 +366,13 @@ public function constructorTypesProvider(): array
             [DefaultValue::class, 'foo', null],
         ];
     }
+
+    /**
+     * @requires PHP 7.4
+     */
+    public function testTypedProperties(): void
+    {
+        $this->assertEquals([new Type(Type::BUILTIN_TYPE_OBJECT, false, Dummy::class)], $this->extractor->getTypes(Php74Dummy::class, 'dummy'));
+        $this->assertEquals([new Type(Type::BUILTIN_TYPE_BOOL, true)], $this->extractor->getTypes(Php74Dummy::class, 'nullableBoolProp'));
+    }
 }

src/Symfony/Component/PropertyInfo/Tests/Fixtures/Php74Dummy.php

@@ -0,0 +1,21 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\PropertyInfo\Tests\Fixtures;
+
+/**
+ * @author Kévin Dunglas <dunglas@gmail.com>
+ */
+class Php74Dummy
+{
+    public Dummy $dummy;
+    private ?bool $nullableBoolProp;
+}