diff --git a/bin/test.rb b/bin/test.rb
index 6071e996..118480e7 100755
--- a/bin/test.rb
+++ b/bin/test.rb
@@ -19,7 +19,7 @@
 require "fileutils"
 require "rbconfig"
 require "shellwords"
-require 'optparse'
+require "optparse"
 
 DEFAULT_PHP_NAME = "php"
 CB_PHP_NAME = ENV.fetch("CB_PHP_NAME", DEFAULT_PHP_NAME)
@@ -130,7 +130,7 @@ def find_extension(name_pattern, project_root, module_location_candidates)
 
 php_unit_phar = File.join(build_root, "phpunit.phar")
 unless File.file?(php_unit_phar)
-  php_unit_version = "9.5"
+  php_unit_version = "10.5.38"
   php_unit_url = "https://phar.phpunit.de/phpunit-#{php_unit_version}.phar"
   FileUtils.mkdir_p(File.dirname(php_unit_phar))
   run("curl -L -o #{php_unit_phar.shellescape} #{php_unit_url}")
@@ -159,9 +159,7 @@ def find_extension(name_pattern, project_root, module_location_candidates)
   end
 end
 
-if extra_php_args.empty?
-  abort "Unable to find the module. Candidates: #{module_location_candidates.inspect}"
-end
+abort "Unable to find the module. Candidates: #{module_location_candidates.inspect}" if extra_php_args.empty?
 
 tests = ARGV.to_a
 tests << File.join(project_root, "tests") if tests.empty?
diff --git a/tests/Helpers/ConsistencyUtils.php b/tests/Helpers/ConsistencyUtils.php
index f3f8e496..44617ef7 100644
--- a/tests/Helpers/ConsistencyUtils.php
+++ b/tests/Helpers/ConsistencyUtils.php
@@ -254,7 +254,7 @@ public function waitUntilCollectionDropped(string $bucketName, string $scopeName
         );
     }
 
-    public function waitUntilBucketUpdated(string $bucketName, callable $predicate, string $errorMsg = null): void
+    public function waitUntilBucketUpdated(string $bucketName, callable $predicate, ?string $errorMsg = null): void
     {
         fprintf(STDERR, "waiting until bucket %s has been updated\n", $bucketName);
 
@@ -267,7 +267,7 @@ public function waitUntilBucketUpdated(string $bucketName, callable $predicate,
         );
     }
 
-    public function waitUntilCollectionUpdated(string $bucketName, string $scopeName, string $collectionName, callable $predicate, string $errorMsg = null): void
+    public function waitUntilCollectionUpdated(string $bucketName, string $scopeName, string $collectionName, callable $predicate, ?string $errorMsg = null): void
     {
         fprintf(STDERR, "waiting until collection %s on scope %s on bucket %s has updated\n", $collectionName, $scopeName, $bucketName);
 
diff --git a/tests/Helpers/CouchbaseTestCase.php b/tests/Helpers/CouchbaseTestCase.php
index 37793f8e..273c567d 100644
--- a/tests/Helpers/CouchbaseTestCase.php
+++ b/tests/Helpers/CouchbaseTestCase.php
@@ -100,7 +100,7 @@ public function connectClusterUnique(?ClusterOptions $options = null): ClusterIn
         return Cluster::connect($connstr, $options);
     }
 
-    public function openBucket(string $name = null): BucketInterface
+    public function openBucket(?string $name = null): BucketInterface
     {
         if ($name == null) {
             $name = self::env()->bucketName();
@@ -108,7 +108,7 @@ public function openBucket(string $name = null): BucketInterface
         return $this->connectCluster()->bucket($name);
     }
 
-    public function defaultCollection(string $bucketName = null): CollectionInterface
+    public function defaultCollection(?string $bucketName = null): CollectionInterface
     {
         if ($bucketName == null) {
             $bucketName = self::env()->bucketName();
@@ -121,7 +121,7 @@ public function consistencyUtil(): ConsistencyUtils
         return self::env()->consistencyUtil();
     }
 
-    public function uniqueId(string $prefix = null): string
+    public function uniqueId(?string $prefix = null): string
     {
         if ($prefix != null) {
             return sprintf("%s_%s", $prefix, self::env()::randomId());