Narrow return value of EntityInterface->id() by previous calls to isNew on an instance of EntityInterface (#900)

* Narrow return value of `EntityInterface->id()` by previous calls to `isNew` on an instance of `EntityInterface`

* simplify/formatting/ address phpstan deprecation about false

* phpcs

---------

Co-authored-by: Matt Glaman <[email protected]>

Author: dpi

extension.neon

@@ -287,6 +287,9 @@ services:
 		class: mglaman\PHPStanDrupal\Drupal\EntityDataRepository
 		arguments:
 			entityMapping: %drupal.entityMapping%
+	-
+		class: mglaman\PHPStanDrupal\Type\EntityIdNarrowedByNew
+		tags: [phpstan.broker.dynamicMethodReturnTypeExtension]
 	-
 		class: mglaman\PHPStanDrupal\Type\EntityTypeManagerGetStorageDynamicReturnTypeExtension
 		tags: [phpstan.broker.dynamicMethodReturnTypeExtension]

src/Type/EntityIdNarrowedByNew.php

@@ -0,0 +1,49 @@
+<?php declare(strict_types=1);
+
+namespace mglaman\PHPStanDrupal\Type;
+
+use Drupal\Core\Entity\EntityInterface;
+use PhpParser\Node\Expr\MethodCall;
+use PhpParser\Node\Identifier;
+use PHPStan\Analyser\Scope;
+use PHPStan\Reflection\MethodReflection;
+use PHPStan\Type\DynamicMethodReturnTypeExtension;
+use PHPStan\Type\IntegerType;
+use PHPStan\Type\NullType;
+use PHPStan\Type\StringType;
+use PHPStan\Type\Type;
+use PHPStan\Type\TypeCombinator;
+
+/**
+ * @author Daniel Phin <[email protected]>
+ */
+class EntityIdNarrowedByNew implements DynamicMethodReturnTypeExtension
+{
+
+    public function getClass(): string
+    {
+        return EntityInterface::class;
+    }
+
+    public function isMethodSupported(MethodReflection $methodReflection): bool
+    {
+        return $methodReflection->getName() === 'id';
+    }
+
+    public function getTypeFromMethodCall(
+        MethodReflection $methodReflection,
+        MethodCall $methodCall,
+        Scope $scope
+    ): ?Type {
+        $isNewMethodCall = new MethodCall($methodCall->var, new Identifier('isNew'));
+        if ($scope->getType($isNewMethodCall)->isFalse()->yes()) {
+            return TypeCombinator::union(new IntegerType(), new StringType());
+        }
+
+        return TypeCombinator::union(
+            new IntegerType(),
+            new StringType(),
+            new NullType()
+        );
+    }
+}

stubs/Drupal/Core/Entity/EntityInterface.stub

@@ -4,4 +4,7 @@ namespace Drupal\Core\Entity;
 
 interface EntityInterface {
 
+    public function id(): string|int|null;
+    public function isNew(): bool;
+
 }

tests/src/Type/data/entity.php

@@ -3,6 +3,7 @@
 namespace DrupalEntity;
 
 use Drupal\node\Entity\Node;
+use Drupal\node\NodeInterface;
 use function PHPStan\Testing\assertType;
 
 assertType('Drupal\node\Entity\Node', $node = Node::create(['type' => 'page', 'title' => 'foo']));
@@ -18,3 +19,12 @@
 assertType('array<Drupal\node\Entity\Node>', Node::loadMultiple([42, 29]));
 assertType('array<Drupal\node\Entity\Node>', Node::loadMultiple(['42', '29']));
 assertType('array<Drupal\node\Entity\Node>', Node::loadMultiple(NULL));
+
+assert($id1 instanceof NodeInterface);
+assertType('int|string|null', $id1->id());
+assert($id2 instanceof NodeInterface);
+assert($id2->isNew() === TRUE);
+assertType('int|string|null', $id2->id());
+assert($id3 instanceof NodeInterface);
+assert($id3->isNew() === FALSE);
+assertType('int|string', $id3->id());