From 7848dfb294dfab30e9994a38184a5c7d298e11d4 Mon Sep 17 00:00:00 2001
From: Kostiantyn Miakshyn <molodchick@gmail.com>
Date: Sun, 7 Dec 2025 22:59:42 +0100
Subject: [PATCH] fix: Allow `num_buckets` to be equal as `min_bucket`

Signed-off-by: Kostiantyn Miakshyn <molodchick@gmail.com>
---
 lib/private/Files/ObjectStore/Mapper.php   | 4 ++++
 tests/lib/Files/ObjectStore/MapperTest.php | 4 ++--
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/lib/private/Files/ObjectStore/Mapper.php b/lib/private/Files/ObjectStore/Mapper.php
index f62a1576caa..a8f0a58e4e0 100644
--- a/lib/private/Files/ObjectStore/Mapper.php
+++ b/lib/private/Files/ObjectStore/Mapper.php
@@ -30,6 +30,10 @@ class Mapper {
 			? (int)$this->config['arguments']['min_bucket']
 			: 0;
 
+		if ($minBucket === $numBuckets) {
+			return (string)$minBucket;
+		}
+
 		$hash = md5($this->user->getUID());
 		$num = hexdec(substr($hash, 0, 4));
 		return (string)(($num % ($numBuckets - $minBucket)) + $minBucket);
diff --git a/tests/lib/Files/ObjectStore/MapperTest.php b/tests/lib/Files/ObjectStore/MapperTest.php
index c3c73e0e7b5..1726b0d01fc 100644
--- a/tests/lib/Files/ObjectStore/MapperTest.php
+++ b/tests/lib/Files/ObjectStore/MapperTest.php
@@ -24,6 +24,7 @@ class MapperTest extends \Test\TestCase {
 	public static function dataGetBucket(): array {
 		return [
 			['user', 64, 0, '17'],
+			['user', 64, 64, '64'],
 			['USER', 64, 0, '0'],
 			['bc0e8b52-a66c-1035-90c6-d9663bda9e3f', 64, 0, '56'],
 			['user', 8, 0, '1'],
@@ -41,8 +42,7 @@ class MapperTest extends \Test\TestCase {
 	#[\PHPUnit\Framework\Attributes\DataProvider('dataGetBucket')]
 	public function testGetBucket($username, $numBuckets, $bucketShift, $expectedBucket): void {
 		$mapper = new Mapper($this->user, ['arguments' => ['min_bucket' => $bucketShift]]);
-		$this->user->expects($this->once())
-			->method('getUID')
+		$this->user->method('getUID')
 			->willReturn($username);
 
 		$result = $mapper->getBucket($numBuckets);