fix(occ): pass empty string instead of null to user search in home list commands

user:home:list-dirs and user:home:list-users --all passed null as the
search pattern to IUserManager::search(). On PHP 8 the null reached
Connection::escapeLikeParameter(string $param) and raised a TypeError,
aborting the command. Use the empty string '' instead, which is the
established "match all" sentinel recognised by UserSearch::isSearchable()
and used by every other caller.

Fixes #41630

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Signed-off-by: Thomas Müller <1005065+DeepDiver1975@users.noreply.github.com>

Author: DeepDiver1975

changelog/unreleased/41630

@@ -0,0 +1,10 @@
+Bugfix: Fix user:home:list-dirs and user:home:list-users crashing on PHP 8
+
+The occ commands user:home:list-dirs and user:home:list-users --all passed
+null as the search pattern to IUserManager::search() to mean "all users".
+On PHP 8 the null reached Connection::escapeLikeParameter(string $param) and
+raised a TypeError, aborting the command. Both commands now pass the empty
+string, which is the established "match all" sentinel used by every other
+caller.
+
+https://github.com/owncloud/core/issues/41630

core/Command/User/HomeListDirs.php

@@ -52,7 +52,7 @@ protected function execute(InputInterface $input, OutputInterface $output): int
 			$output->writeln('<info>We detected that the instance is running on a S3 primary object storage, home directories might not be accurate</info>');
 		}
 
-		$users = $this->userManager->search(null);
+		$users = $this->userManager->search('');
 		$homePaths = [];
 		foreach ($users as $user) {
 			$home = $user->getHome();

core/Command/User/HomeListUsers.php

@@ -79,7 +79,7 @@ protected function execute(InputInterface $input, OutputInterface $output): int
 				$output->writeln('<error>--all and path option cannot be given together</error>');
 				return 1;
 			}
-			$users = $this->userManager->search(null, null, null, true);
+			$users = $this->userManager->search('', null, null, true);
 			$outputData = [];
 			foreach ($users as $user) {
 				$home = $user->getHome();

tests/Core/Command/User/HomeListDirsTest.php

@@ -70,7 +70,10 @@ public function testCommandInput($objectStorageUsed) {
 		$user2Mock = $this->createMock(IUser::class);
 		$user2Mock->method('getHome')->willReturn("$homePath/user2");
 
-		$this->userManager->method('search')->willReturn([$user1Mock, $user2Mock]);
+		$this->userManager->expects($this->once())
+			->method('search')
+			->with($this->identicalTo(''))
+			->willReturn([$user1Mock, $user2Mock]);
 		$this->commandTester->execute([]);
 		$output = $this->commandTester->getDisplay();
 		$this->assertStringContainsString($homePath, $output);

tests/Core/Command/User/HomeListUsersTest.php

@@ -114,7 +114,10 @@ public function testCommandInputAll() {
 			->getMock();
 		$userObject->method('getHome')->willReturn($path . '/' . $uid);
 		$userObject->method('getUID')->willReturn($uid);
-		$this->userManager->method('search')->willReturn([$uid => $userObject]);
+		$this->userManager->expects($this->once())
+			->method('search')
+			->with($this->identicalTo(''), null, null, true)
+			->willReturn([$uid => $userObject]);
 
 		$this->commandTester->execute(['--all' => true]);
 		$output = $this->commandTester->getDisplay();