removeMulti does not remove documents.

% cat t2.php
<?php

// NOTE: Change the below vendor path to your own.
// require_once '../../../vendor/autoload.php';
require_once '/usr/local/share/pear/Couchbase/autoload.php';

use Couchbase\ClusterOptions;
use Couchbase\Cluster;
use Couchbase\TransactionOptions;
use Couchbase\TransactionAttemptContext;

$clusterOptions = new ClusterOptions();
$clusterOptions->credentials('Administrator', 'password');
$cluster = new Cluster('couchbase://localhost', $clusterOptions);

$bucket = $cluster->bucket('my_bucket');
$scope = $bucket->defaultScope();
$collection = $scope->collection('_default');

$collection->upsert('111','{}');
$collection->upsert('222','{}');

echo PHP_EOL;
echo $collection->exists('111')->exists() ? '111 is Exists' : '';
echo PHP_EOL;
echo $collection->exists('222')->exists() ? '222 is Exists' : '';
echo PHP_EOL;

echo 'Remove 111 and 222';
echo PHP_EOL;
$result = $collection->removeMulti([
'111',
'222',
]);

print_r ( $result ) ;

echo $collection->exists('111')->exists() ? '111 is Exists' : '111 removed';
echo PHP_EOL;
echo $collection->exists('222')->exists() ? '222 is Exists' : '222 removed';
echo PHP_EOL;

?>
michaelreiche@HQML0612s-MBP Couchbase % php -e t2.php
PHP Warning: Module "couchbase" is already loaded in Unknown on line 0

Warning: Module "couchbase" is already loaded in Unknown on line 0
PHP Warning: Module "couchbase" is already loaded in Unknown on line 0

Warning: Module "couchbase" is already loaded in Unknown on line 0

111 is Exists
222 is Exists
Remove 111 and 222
Array
(
[0] => Couchbase\MutationResult Object
(
[id:Couchbase\Result:private] => 111
[cas:Couchbase\Result:private] => 176635d87e5e0000
[error:Couchbase\Result:private] =>
[mutationToken:Couchbase\MutationResult:private] =>
)

[1] => Couchbase\MutationResult Object
(
[id:Couchbase\Result:private] => 222
[cas:Couchbase\Result:private] => 176635d87e6c0000
[error:Couchbase\Result:private] =>
[mutationToken:Couchbase\MutationResult:private] =>
)

)
111 is Exists
222 is Exists
michaelreiche@HQML0612s-MBP Couchbase %