Fix inference of type of Model::find() to base on framework behavior (#18)

Author: paulbalandan

src/Type/ModelFindReturnTypeExtension.php

@@ -20,6 +20,7 @@
 use PHPStan\Reflection\MethodReflection;
 use PHPStan\Type\Accessory\AccessoryArrayListType;
 use PHPStan\Type\ArrayType;
+use PHPStan\Type\Constant\ConstantArrayType;
 use PHPStan\Type\DynamicMethodReturnTypeExtension;
 use PHPStan\Type\IntegerType;
 use PHPStan\Type\IntersectionType;
@@ -49,11 +50,11 @@ public function getTypeFromMethodCall(MethodReflection $methodReflection, Method
         $methodName = $methodReflection->getName();
 
         if ($methodName === 'find') {
-            return $this->getTypeFromFind($methodReflection, $methodCall, $scope);
+            return $this->getTypeFromFind($methodCall, $scope);
         }
 
         if ($methodName === 'findAll') {
-            return $this->getTypeFromFindAll($methodReflection, $methodCall, $scope);
+            return $this->getTypeFromFindAll($methodCall, $scope);
         }
 
         $classReflection = $this->getClassReflection($methodCall, $scope);
@@ -69,23 +70,23 @@ private function getClassReflection(MethodCall $methodCall, Scope $scope): Class
         return current($classTypes);
     }
 
-    private function getTypeFromFind(MethodReflection $methodReflection, MethodCall $methodCall, Scope $scope): Type
+    private function getTypeFromFind(MethodCall $methodCall, Scope $scope): Type
     {
         $args = $methodCall->getArgs();
 
         if (! isset($args[0])) {
-            return $this->getTypeFromFindAll($methodReflection, $methodCall, $scope);
+            return $this->getTypeFromFindAll($methodCall, $scope);
         }
 
         return TypeTraverser::map(
             $scope->getType($args[0]->value),
-            function (Type $idType, callable $traverse) use ($methodReflection, $methodCall, $scope): Type {
+            function (Type $idType, callable $traverse) use ($methodCall, $scope): Type {
                 if ($idType instanceof UnionType || $idType instanceof IntersectionType) {
                     return $traverse($idType);
                 }
 
-                if ($idType->isNull()->yes()) {
-                    return $this->getTypeFromFindAll($methodReflection, $methodCall, $scope);
+                if ($idType->isArray()->yes() && ! $idType->isIterableAtLeastOnce()->yes()) {
+                    return new ConstantArrayType([], []);
                 }
 
                 if ($idType->isInteger()->yes() || $idType->isString()->yes()) {
@@ -94,12 +95,12 @@ function (Type $idType, callable $traverse) use ($methodReflection, $methodCall,
                     return TypeCombinator::addNull($this->modelFetchedReturnTypeHelper->getFetchedReturnType($classReflection, $methodCall, $scope));
                 }
 
-                return $this->getTypeFromFindAll($methodReflection, $methodCall, $scope);
+                return $this->getTypeFromFindAll($methodCall, $scope);
             }
         );
     }
 
-    private function getTypeFromFindAll(MethodReflection $methodReflection, MethodCall $methodCall, Scope $scope): Type
+    private function getTypeFromFindAll(MethodCall $methodCall, Scope $scope): Type
     {
         $classReflection = $this->getClassReflection($methodCall, $scope);
 

tests/Type/DynamicMethodReturnTypeExtensionTest.php

@@ -38,5 +38,7 @@ public function testFileAsserts(string $assertType, string $file, mixed ...$args
     public static function provideFileAssertsCases(): iterable
     {
         yield from self::gatherAssertTypes(__DIR__ . '/data/model-find.php');
+
+        yield from self::gatherAssertTypes(__DIR__ . '/data/bug-7.php');
     }
 }

tests/Type/data/bug-7.php

@@ -0,0 +1,23 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * This file is part of CodeIgniter 4 framework.
+ *
+ * (c) 2023 CodeIgniter Foundation <[email protected]>
+ *
+ * For the full copyright and license information, please view
+ * the LICENSE file that was distributed with this source code.
+ */
+
+use CodeIgniter\Shield\Models\UserModel;
+
+use function PHPStan\Testing\assertType;
+
+$users = model(UserModel::class);
+assertType('array{}', $users->find([]));
+assertType('list<CodeIgniter\Shield\Entities\User>', $users->find([1]));
+
+// Model::find() does not fail if not `array|int|string|null` but defaults to get all
+assertType('list<CodeIgniter\Shield\Entities\User>', $users->find(new \stdClass()));