Improved the types this entity extension works on

Also:
- Added support for 4 certain special properties original, target_id
  entity and value.
- Split the inline class into separate files for better maintainability.

Remove the need for the Drupal autoloader to work

This allows Travis' PHPStan CLI to check this extention.

Author: Christian Bläul

extension.neon

@@ -36,5 +36,5 @@ services:
 		class: PHPStan\Type\ServiceDynamicReturnTypeExtension
 		tags: [phpstan.broker.dynamicMethodReturnTypeExtension]
 	-
-		class: PHPStan\Reflection\EntityFieldsViaMagic
+		class: PHPStan\Reflection\EntityFieldsViaMagicReflectionExtension
 		tags: [phpstan.broker.propertiesClassReflectionExtension]

src/Reflection/EntityFieldReflection.php

@@ -0,0 +1,67 @@
+<?php
+
+namespace PHPStan\Reflection;
+
+use PHPStan\Type\ObjectType;
+use PHPStan\Type\Type;
+
+/**
+ * Allows field access via magic methods
+ *
+ * See \Drupal\Core\Entity\ContentEntityBase::__get and ::__set.
+ */
+class EntityFieldReflection implements PropertyReflection
+{
+
+  /** @var ClassReflection */
+    private $declaringClass;
+
+  /** @var string */
+    private $propertyName;
+
+    public function __construct(ClassReflection $declaringClass, string $propertyName)
+    {
+        $this->declaringClass = $declaringClass;
+        $this->propertyName = $propertyName;
+    }
+
+    public function getType(): Type
+    {
+        if ($this->propertyName == 'original') {
+          // See Drupal\Core\Entity\EntityStorageBase::doPreSave
+            return new ObjectType('Drupal\Core\Field\FieldItemListInterface');
+        }
+
+        return new ObjectType('Drupal\Core\Field\FieldItemListInterface');
+    }
+
+    public function getDeclaringClass(): ClassReflection
+    {
+        return $this->declaringClass;
+    }
+
+    public function isStatic(): bool
+    {
+        return false;
+    }
+
+    public function isPrivate(): bool
+    {
+        return false;
+    }
+
+    public function isPublic(): bool
+    {
+        return true;
+    }
+
+    public function isReadable(): bool
+    {
+        return true;
+    }
+
+    public function isWritable(): bool
+    {
+        return true;
+    }
+}

src/Reflection/EntityFieldsViaMagic.php

@@ -0,0 +1,43 @@
+<?php
+
+namespace PHPStan\Reflection;
+
+/**
+ * Allows field access via magic methods
+ *
+ * See \Drupal\Core\Entity\ContentEntityBase::__get and ::__set.
+ */
+class EntityFieldsViaMagicReflectionExtension implements PropertiesClassReflectionExtension
+{
+
+    public function hasProperty(ClassReflection $classReflection, string $propertyName): bool
+    {
+        if ($classReflection->hasNativeProperty($propertyName)) {
+          // Let other parts of PHPStan handle this.
+            return false;
+        }
+
+        $reflection = $classReflection->getNativeReflection();
+        if ($reflection->implementsInterface('Drupal\Core\Entity\EntityInterface')) {
+            return true;
+        }
+        if ($reflection->implementsInterface('Drupal\Core\Field\FieldItemListInterface')) {
+            return FieldItemListPropertyReflection::canHandleProperty($propertyName);
+        }
+
+        return false;
+    }
+
+    public function getProperty(ClassReflection $classReflection, string $propertyName): PropertyReflection
+    {
+        $reflection = $classReflection->getNativeReflection();
+        if ($reflection->implementsInterface('Drupal\Core\Entity\EntityInterface')) {
+            return new EntityFieldReflection($classReflection, $propertyName);
+        }
+        if ($reflection->implementsInterface('Drupal\Core\Field\FieldItemListInterface')) {
+            return new FieldItemListPropertyReflection($classReflection, $propertyName);
+        }
+
+        throw new \LogicException($classReflection->getName() . "::$propertyName should be handled earlier.");
+    }
+}

src/Reflection/EntityFieldsViaMagicReflectionExtension.php

@@ -0,0 +1,80 @@
+<?php
+
+namespace PHPStan\Reflection;
+
+use PHPStan\Type\IntegerType;
+use PHPStan\Type\MixedType;
+use PHPStan\Type\ObjectType;
+use PHPStan\Type\Type;
+
+/**
+ * Allows field access via magic methods
+ *
+ * See \Drupal\Core\Field\FieldItemListInterface::__get and ::__set.
+ */
+class FieldItemListPropertyReflection implements PropertyReflection
+{
+
+  /** @var ClassReflection */
+    private $declaringClass;
+
+  /** @var string */
+    private $propertyName;
+
+    public function __construct(ClassReflection $declaringClass, string $propertyName)
+    {
+        $this->declaringClass = $declaringClass;
+        $this->propertyName = $propertyName;
+    }
+
+    public static function canHandleProperty(string $propertyName): bool
+    {
+        $names = ['entity', 'value', 'target_id'];
+        return in_array($propertyName, $names, true);
+    }
+
+    public function getType(): Type
+    {
+        if ($this->propertyName == 'entity') {
+          // It was a EntityReferenceFieldItemList
+            return new ObjectType('Drupal\Core\Entity\FieldableEntityInterface');
+        }
+        if ($this->propertyName == 'target_id') {
+          // It was a EntityReferenceFieldItemList
+            return new IntegerType();
+        }
+        if ($this->propertyName == 'value') {
+            return new MixedType();
+        }
+    }
+
+    public function getDeclaringClass(): ClassReflection
+    {
+        return $this->declaringClass;
+    }
+
+    public function isStatic(): bool
+    {
+        return false;
+    }
+
+    public function isPrivate(): bool
+    {
+        return false;
+    }
+
+    public function isPublic(): bool
+    {
+        return true;
+    }
+
+    public function isReadable(): bool
+    {
+        return true;
+    }
+
+    public function isWritable(): bool
+    {
+        return true;
+    }
+}