Removing an entity that is contained in a m2m association fails when flush() is called twice

Here is a failing test for #10483.

When an entity is removed that is part of a many-to-many collection, that collection will be updated during the `flush()` operation to no longer contain the entity.

However, afterwards the collection will be in a dirty state and the internal snapshot still contains the removed entity.

That causes the collection to be processed again when `flush()` is called another time. This time, the ORM assumes the entity has been removed from the collection. It will try to build a `DELETE` operation but fails since the entity (from the snapshot) is no longer in the identity map.

Author: mpdude

tests/Doctrine/Tests/ORM/Functional/Ticket/GH10483Test.php

@@ -0,0 +1,114 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Doctrine\Tests\ORM\Functional\Ticket;
+
+use Doctrine\Common\Collections\ArrayCollection;
+use Doctrine\Common\Collections\Collection;
+use Doctrine\ORM\Mapping as ORM;
+use Doctrine\Tests\OrmFunctionalTestCase;
+
+class GH10483Test extends OrmFunctionalTestCase
+{
+    protected function setUp(): void
+    {
+        parent::setUp();
+
+        $this->createSchemaForModels(
+            GH10483Role::class,
+            GH10483User::class
+        );
+    }
+
+    public function testFlushChangedUserAfterRoleHasBeenDeleted(): void
+    {
+        $em = $this->_em;
+
+        $role       = new GH10483Role();
+        $role->name = 'test';
+        $em->persist($role);
+
+        $user       = new GH10483User();
+        $user->name = 'test';
+        $user->roles->add($role);
+        $em->persist($user);
+
+        $em->flush();
+
+        self::assertFalse($user->roles->isDirty());
+
+        $em->remove($role);
+        $em->flush();
+
+        // UnitOfWork::computeAssociationChanges(), lines 968 ff. will remove the removed entity from the collection:
+        self::assertEmpty($user->roles);
+
+        // The UoW left the collection in a dirty state, is that correct?
+        self::assertTrue($user->roles->isDirty()); // <-- might need to assert "false" (?)
+
+        // The collection's snapshot still contains the removed $role entity, is that correct?
+        self::assertSame([$role], $user->roles->getSnapshot()); // <-- might need to assert snapshot being empty (?)
+
+        // Since the collection is dirty and/or has a snapshot that differs from the state,
+        // this flush will try to remove the $role from the collection, and fails when looking for
+        // it in the identity map
+        $em->flush();
+    }
+}
+
+/**
+ * @ORM\Entity
+ */
+class GH10483Role
+{
+    /**
+     * @ORM\Id
+     * @ORM\GeneratedValue(strategy="AUTO")
+     * @ORM\Column(type="integer")
+     *
+     * @var int
+     */
+    public $id;
+
+    /**
+     * @ORM\Column
+     *
+     * @var string
+     */
+    public $name;
+}
+
+/**
+ * @ORM\Entity
+ */
+class GH10483User
+{
+    /**
+     * @ORM\Id
+     * @ORM\GeneratedValue(strategy="AUTO")
+     * @ORM\Column(type="integer")
+     *
+     * @var int
+     */
+    public $id;
+
+    /**
+     * @ORM\Column
+     *
+     * @var string
+     */
+    public $name;
+
+    /**
+     * @ORM\ManyToMany(targetEntity="GH10483Role")
+     *
+     * @var Collection
+     */
+    public $roles;
+
+    public function __construct()
+    {
+        $this->roles = new ArrayCollection();
+    }
+}