Optimize relations resolving

src/RelationMap.php

@@ -191,6 +191,11 @@ private function registerOuterRelation(string $role, string $container, array $r
             return;
         }
 
+        if (isset($relationSchema[Relation::SCHEMA][Relation::INVERSION])) {
+            // handshaked relation, skip
+            return;
+        }
+
         $relation = new ShadowBelongsTo($container, $role, $relationSchema);
         $this->dependencies[$relation->getName()] = $relation;
     }

tests/ORM/Functional/Driver/Common/Integration/Case429/CaseTest.php

@@ -117,14 +117,6 @@ private function makeTables(): void
             'order_item_id' => 'int,nullable',
             'quantity' => 'int',
         ]);
-
-        $this->makeFK('order_item', 'order_id', 'order', 'id', 'NO ACTION', 'CASCADE');
-
-        $this->makeFK('order_item', 'purchase_order_id', 'purchase_order', 'id', 'NO ACTION', 'CASCADE');
-
-        $this->makeFK('purchase_order_item', 'purchase_order_id', 'purchase_order', 'id', 'NO ACTION', 'CASCADE');
-
-        $this->makeFK('purchase_order_item', 'order_item_id', 'order_item', 'id', 'NO ACTION', 'CASCADE');
     }
 
     private function fillData(): void

tests/ORM/Functional/Driver/Common/Integration/Case429/schema.php

@@ -173,7 +173,7 @@
         ],
         Schema::SCOPE => null,
         Schema::TYPECAST => [
-            'id' => 'primary',
+            'id' => 'int',
             'purchase_order_id' => 'int',
             'order_item_id' => 'int',
             'quantity' => 'int',

tests/ORM/Functional/Driver/Common/Integration/Issue489/CaseTest.php

@@ -0,0 +1,41 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Cycle\ORM\Tests\Functional\Driver\Common\Integration\Issue489;
+
+use Cycle\ORM\Tests\Functional\Driver\Common\BaseTest;
+use Cycle\ORM\Tests\Functional\Driver\Common\Integration\Issue489\Entity\User;
+use Cycle\ORM\Tests\Functional\Driver\Common\Integration\IntegrationTestTrait;
+use Cycle\ORM\Tests\Traits\TableTrait;
+
+abstract class CaseTest extends BaseTest
+{
+    use IntegrationTestTrait;
+    use TableTrait;
+
+    public function testSave(): void
+    {
+        $this->captureWriteQueries();
+        $this->save(new User());
+        $this->assertNumWrites(1);
+    }
+
+    public function setUp(): void
+    {
+        // Init DB
+        parent::setUp();
+        $this->makeTables();
+
+        $this->loadSchema(__DIR__ . '/schema.php');
+    }
+
+    private function makeTables(): void
+    {
+        // Make tables
+        $this->makeTable(User::ROLE, [
+            'id' => 'primary', // autoincrement
+            'user_id' => 'int,nullable',
+        ]);
+    }
+}

tests/ORM/Functional/Driver/Common/Integration/Issue489/Entity/User.php

@@ -0,0 +1,15 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Cycle\ORM\Tests\Functional\Driver\Common\Integration\Issue489\Entity;
+
+class User
+{
+    public const ROLE = 'user';
+
+    public ?int $id = null;
+    public ?int $user_id = null;
+    public ?self $user = null;
+    public iterable $users = [];
+}

tests/ORM/Functional/Driver/Common/Integration/Issue489/schema.php

@@ -0,0 +1,65 @@
+<?php
+
+declare(strict_types=1);
+
+use Cycle\ORM\Mapper\Mapper;
+use Cycle\ORM\Relation;
+use Cycle\ORM\Schema\GeneratedField;
+use Cycle\ORM\SchemaInterface as Schema;
+use Cycle\ORM\Select\Repository;
+use Cycle\ORM\Select\Source;
+use Cycle\ORM\Tests\Functional\Driver\Common\Integration\Issue489\Entity\User;
+
+return [
+    'user' => [
+        Schema::ENTITY => User::class,
+        Schema::SOURCE => Source::class,
+        Schema::MAPPER => Mapper::class,
+        Schema::REPOSITORY => Repository::class,
+        Schema::DATABASE => 'default',
+        Schema::TABLE => 'user',
+        Schema::PRIMARY_KEY => ['id'],
+        Schema::FIND_BY_KEYS => ['id'],
+        Schema::COLUMNS => [
+            'id' => 'id',
+            'user_id' => 'user_id',
+        ],
+        Schema::RELATIONS => [
+            'user' => [
+                Relation::TYPE => Relation::BELONGS_TO,
+                Relation::TARGET => 'user',
+                Relation::LOAD => Relation::LOAD_PROMISE,
+                Relation::SCHEMA => [
+                    Relation::CASCADE => true,
+                    Relation::NULLABLE => true,
+                    Relation::INNER_KEY => 'user_id',
+                    Relation::OUTER_KEY => ['id'],
+                    // Relation::INVERSION => 'users',
+                ],
+            ],
+            'users' => [
+                Relation::TYPE => Relation::HAS_MANY,
+                Relation::TARGET => 'user',
+                Relation::LOAD => Relation::LOAD_PROMISE,
+                Relation::SCHEMA => [
+                    Relation::CASCADE => true,
+                    Relation::NULLABLE => false, // The reason for the issue
+                    Relation::WHERE => [],
+                    Relation::ORDER_BY => [],
+                    Relation::INNER_KEY => ['id'],
+                    Relation::OUTER_KEY => 'user_id',
+                    // Relation::INVERSION => 'user',
+                ],
+            ],
+        ],
+        Schema::SCOPE => null,
+        Schema::TYPECAST => [
+            'id' => 'int',
+            'user_id' => 'int',
+        ],
+        Schema::SCHEMA => [],
+        Schema::GENERATED_FIELDS => [
+            'id' => GeneratedField::ON_INSERT,
+        ],
+    ],
+];

tests/ORM/Functional/Driver/MySQL/Integration/Issue489/CaseTest.php

@@ -0,0 +1,17 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Cycle\ORM\Tests\Functional\Driver\MySQL\Integration\Issue489;
+
+// phpcs:ignore
+use Cycle\ORM\Tests\Functional\Driver\Common\Integration\Issue489\CaseTest as CommonClass;
+
+/**
+ * @group driver
+ * @group driver-mysql
+ */
+class CaseTest extends CommonClass
+{
+    public const DRIVER = 'mysql';
+}

tests/ORM/Functional/Driver/Postgres/Integration/Issue489/CaseTest.php

@@ -0,0 +1,17 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Cycle\ORM\Tests\Functional\Driver\Postgres\Integration\Issue489;
+
+// phpcs:ignore
+use Cycle\ORM\Tests\Functional\Driver\Common\Integration\Issue489\CaseTest as CommonClass;
+
+/**
+ * @group driver
+ * @group driver-postgres
+ */
+class CaseTest extends CommonClass
+{
+    public const DRIVER = 'postgres';
+}

tests/ORM/Functional/Driver/SQLServer/Integration/Issue489/CaseTest.php

@@ -0,0 +1,17 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Cycle\ORM\Tests\Functional\Driver\SQLServer\Integration\Issue489;
+
+// phpcs:ignore
+use Cycle\ORM\Tests\Functional\Driver\Common\Integration\Issue489\CaseTest as CommonClass;
+
+/**
+ * @group driver
+ * @group driver-sqlserver
+ */
+class CaseTest extends CommonClass
+{
+    public const DRIVER = 'sqlserver';
+}

tests/ORM/Functional/Driver/SQLite/Integration/Issue489/CaseTest.php

@@ -0,0 +1,17 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Cycle\ORM\Tests\Functional\Driver\SQLite\Integration\Issue489;
+
+// phpcs:ignore
+use Cycle\ORM\Tests\Functional\Driver\Common\Integration\Issue489\CaseTest as CommonClass;
+
+/**
+ * @group driver
+ * @group driver-sqlite
+ */
+class CaseTest extends CommonClass
+{
+    public const DRIVER = 'sqlite';
+}