From 5924a2e3ecb2e7d6384a293396e9562b22d54548 Mon Sep 17 00:00:00 2001
From: Robin Appelman <robin@icewind.nl>
Date: Tue, 13 Jan 2026 15:17:49 +0100
Subject: [PATCH] feat: add api to get a user object without verifying they
 exist

Signed-off-by: Robin Appelman <robin@icewind.nl>
---
 lib/private/User/Manager.php   |  4 ++++
 lib/public/IUserManager.php    | 18 ++++++++++++++++++
 tests/lib/User/ManagerTest.php | 22 ++++++++++++++++++++++
 3 files changed, 44 insertions(+)

diff --git a/lib/private/User/Manager.php b/lib/private/User/Manager.php
index 2bea9bb65dd..2c79ba3e618 100644
--- a/lib/private/User/Manager.php
+++ b/lib/private/User/Manager.php
@@ -833,4 +833,8 @@ class Manager extends PublicEmitter implements IUserManager {
 			}
 		} while (count($userIds) === $batchSize && $limit !== 0);
 	}
+
+	public function getExistingUser(string $userId, ?string $displayName = null): IUser {
+		return new LazyUser($userId, $this, $displayName);
+	}
 }
diff --git a/lib/public/IUserManager.php b/lib/public/IUserManager.php
index caf1a704cce..18962f9f6d9 100644
--- a/lib/public/IUserManager.php
+++ b/lib/public/IUserManager.php
@@ -62,6 +62,9 @@ interface IUserManager {
 	/**
 	 * get a user by user id
 	 *
+	 * If you're already 100% sure that the user exists,
+	 * consider IUserManager::getExistingUser which has less overhead.
+	 *
 	 * @param string $uid
 	 * @return \OCP\IUser|null Either the user or null if the specified user does not exist
 	 * @since 8.0.0
@@ -246,4 +249,19 @@ interface IUserManager {
 	 * @since 32.0.0
 	 */
 	public function getSeenUsers(int $offset = 0, ?int $limit = null): \Iterator;
+
+	/**
+	 * Get a user by user id without validating that the user exists.
+	 *
+	 * This should only be used if you're certain that the provided user id exists in the system.
+	 * Using this to get a user object for a non-existing user will lead to unexpected behavior down the line.
+	 *
+	 * If you're not 100% sure that the user exists, use IUserManager::get instead.
+	 *
+	 * @param string $userId
+	 * @param ?string $displayName If the display name is known in advance you can provide it so it doesn't have to be fetched again
+	 * @return IUser
+	 * @since 33.0.0
+	 */
+	public function getExistingUser(string $userId, ?string $displayName = null): IUser;
 }
diff --git a/tests/lib/User/ManagerTest.php b/tests/lib/User/ManagerTest.php
index 7dadc4e9e8f..17007aa8a24 100644
--- a/tests/lib/User/ManagerTest.php
+++ b/tests/lib/User/ManagerTest.php
@@ -740,4 +740,26 @@ class ManagerTest extends TestCase {
 		$this->assertEquals('uid1', $users[0]->getUID());
 		$this->assertEquals('uid2', $users[1]->getUID());
 	}
+
+	public function testGetExistingUser() {
+		$backend = $this->createMock(\Test\Util\User\Dummy::class);
+		$backend->method('userExists')
+			->with('foobar')
+			->willReturn(true);
+		$backend->method('getDisplayName')
+			->willReturn('Foo Bar');
+		$backend->method('implementsActions')
+			->willReturnCallback(fn (int $action) => $action === Backend::GET_DISPLAYNAME);
+
+		$manager = new Manager($this->config, $this->cacheFactory, $this->eventDispatcher, $this->logger);
+		$manager->registerBackend($backend);
+
+		$user = $manager->getExistingUser('foobar');
+		$this->assertEquals('foobar', $user->getUID());
+		$this->assertEquals('Foo Bar', $user->getDisplayName());
+
+		$user = $manager->getExistingUser('nobody', 'None');
+		$this->assertEquals('nobody', $user->getUID());
+		$this->assertEquals('None', $user->getDisplayName());
+	}
 }