diff --git a/tests/phpunit/bootstrap.php b/tests/phpunit/bootstrap.php
index f332a579ea1..d54fde84bdb 100644
--- a/tests/phpunit/bootstrap.php
+++ b/tests/phpunit/bootstrap.php
@@ -143,7 +143,7 @@ if ( !$hasIntegrationTests ) {
 	// For simplicity, getPHPUnitExtensionsAndSkins uses `\n\nTESTPATHS\n\n` to separate the lists of JSON files and
 	// additional test paths, so split the output into the individual lists.
 	[ $pathsToJsonFilesStr, $testPathsStr ] = explode( "\n\nTESTPATHS\n\n", $extensionData );
-	$pathsToJsonFiles = explode( "\n", $pathsToJsonFilesStr );
+	$pathsToJsonFiles = $pathsToJsonFilesStr ? explode( "\n", $pathsToJsonFilesStr ) : [];
 	$testPaths = explode( "\n", $testPathsStr );
 
 	$extensionProcessor = new ExtensionProcessor();
diff --git a/tests/phpunit/getPHPUnitExtensionsAndSkins.php b/tests/phpunit/getPHPUnitExtensionsAndSkins.php
index e0d45ca2d3f..fe9a682fe4b 100755
--- a/tests/phpunit/getPHPUnitExtensionsAndSkins.php
+++ b/tests/phpunit/getPHPUnitExtensionsAndSkins.php
@@ -36,6 +36,7 @@ echo "\n\nTESTPATHS\n\n";
 // just the config needed to create a hook container, as early as when ExtensionsTestSuite::suite is called.
 // This particular hack can be removed once the UnitTestsList hook is removed (T298509)
 $registry = ExtensionRegistry::getInstance();
+$paths = [];
 foreach ( $registry->getAllThings() as $info ) {
 	$paths[] = dirname( $info['path'] ) . '/tests/phpunit';
 }