From 6a1863283b47afe20bb43f942544a8a7fd615460 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Michael=20Vo=C5=99=C3=AD=C5=A1ek?= <mvorisek@mvorisek.cz>
Date: Sun, 29 May 2022 20:13:04 +0200
Subject: [PATCH] Return null when traversing entity 1:1 not found

---
 src/Data/HintableModelTrait.php       | 11 ++++++
 tests/Data/HintableModelArrayTest.php | 50 +++++++++++++++++++++++----
 2 files changed, 55 insertions(+), 6 deletions(-)

diff --git a/src/Data/HintableModelTrait.php b/src/Data/HintableModelTrait.php
index a80ec61..f2f5c41 100644
--- a/src/Data/HintableModelTrait.php
+++ b/src/Data/HintableModelTrait.php
@@ -136,6 +136,17 @@ public function &__get(string $name)
                 /** @var Model */
                 $model = $this->ref($hProp->fieldName);
 
+                // HasOne/ContainsOne::ref() method returns an unloaded entity when traversing entity not found
+                if ($model->isEntity()) {
+                    $this->assertIsEntity();
+
+                    if (!$model->isLoaded()) {
+                        $res = null;
+
+                        return $res;
+                    }
+                }
+
                 if ($hProp->refType === HintablePropertyDef::REF_TYPE_ONE) {
                     // TODO this requires checking all parents!
 //                    // ensure no more than one record can load
diff --git a/tests/Data/HintableModelArrayTest.php b/tests/Data/HintableModelArrayTest.php
index afe97fa..baaf26c 100644
--- a/tests/Data/HintableModelArrayTest.php
+++ b/tests/Data/HintableModelArrayTest.php
@@ -7,6 +7,7 @@
 use Atk4\Core\Phpunit\TestCase;
 use Atk4\Data\Exception;
 use Atk4\Data\Persistence;
+use Mvorisek\Atk4\Hintable\Phpstan\PhpstanUtil;
 
 /**
  * @coversDefaultClass \Mvorisek\Atk4\Hintable\Data\HintableModelTrait
@@ -33,7 +34,9 @@ public function testFieldName(): void
     public function testFieldNameUndeclaredException(): void
     {
         $model = new Model\Simple();
+
         $this->expectException(Exception::class);
+        $this->expectExceptionMessage('Hintable property is not defined');
         $model->fieldName()->undeclared; // @phpstan-ignore-line
     }
 
@@ -73,6 +76,11 @@ protected function createDatabaseForRefTest(): Persistence
             $standard12 = (clone $standardTemplate)
                 ->set(Model\Standard::hinting()->fieldName()->simpleOneId, $simple3->id)
                 ->save();
+            /* 13 - null simpleOneId */ (clone $standardTemplate)
+                ->save();
+            /* 14 - invalid simpleOneId */ (clone $standardTemplate)
+                ->set(Model\Standard::hinting()->fieldName()->simpleOneId, 999)
+                ->save();
 
             $simple1
                 ->set(Model\Simple::hinting()->fieldName()->refId, $standard11->id)
@@ -135,27 +143,57 @@ public function testRefMany(): void
         }, iterator_to_array($model->load(12)->simpleMany)));
     }
 
-    public function testRefManyIsNotEntity(): void
+    public function testRefOneLoadOneException(): void
     {
         $db = $this->createDatabaseForRefTest();
         $model = new Model\Standard($db);
-        $this->assertFalse($model->load(12)->simpleMany->isEntity());
+        $modelSimple = $model->simpleOne;
+
+        $this->expectException(Exception::class);
+        $this->expectExceptionMessage('more than one record can be loaded');
+        $modelSimple->loadOne();
     }
 
-    public function testRefOneLoadOneException(): void
+    public function testRefManyLoadOneException(): void
     {
         $db = $this->createDatabaseForRefTest();
         $model = new Model\Standard($db);
+        $modelSimple = $model->simpleMany;
+
         $this->expectException(Exception::class);
-        $model->simpleOne->loadOne();
+        $this->expectExceptionMessage('more than one record can be loaded');
+        $modelSimple->loadOne();
     }
 
-    public function testRefManyLoadOneException(): void
+    public function testRefOneTraverseNullException(): void
+    {
+        $db = $this->createDatabaseForRefTest();
+        $model = new Model\Standard($db);
+        $entity13 = $model->load(13);
+
+        $this->expectException(Exception::class);
+        $this->expectExceptionMessage('Unable to traverse on null value');
+        PhpstanUtil::ignoreUnusedVariable($entity13->simpleOne);
+    }
+
+    public function testRefOneTraverseInvalidException(): void
+    {
+        $db = $this->createDatabaseForRefTest();
+        $model = new Model\Standard($db);
+        $entity14 = $model->load(14);
+
+        $this->assertNull($entity14->simpleOne); // TODO should throw
+    }
+
+    public function testRefManyTraverseNullException(): void
     {
         $db = $this->createDatabaseForRefTest();
         $model = new Model\Standard($db);
+        $entityNull = $model->createEntity();
+
         $this->expectException(Exception::class);
-        $model->simpleMany->loadOne();
+        $this->expectExceptionMessage('Unable to traverse on null value');
+        PhpstanUtil::ignoreUnusedVariable($entityNull->simpleMany);
     }
 
     public function testPhpstanModelIteratorAggregate(): void