diff --git a/lib/ImportExport/AbstractImportExport.php b/lib/ImportExport/AbstractImportExport.php
index 54452301..3a234438 100644
--- a/lib/ImportExport/AbstractImportExport.php
+++ b/lib/ImportExport/AbstractImportExport.php
@@ -141,7 +141,7 @@ abstract class AbstractImportExport {
         return true;
     }
 
-    abstract public function parse(string $data, bool $flat): array;
+    abstract protected function parse(string $data, bool $flat): array;
 
     abstract public function export(string $user, bool $flat = false): string;
 
diff --git a/lib/ImportExport/OPML.php b/lib/ImportExport/OPML.php
index 92252696..aa311f8a 100644
--- a/lib/ImportExport/OPML.php
+++ b/lib/ImportExport/OPML.php
@@ -10,7 +10,7 @@ use JKingWeb\Arsse\Arsse;
 use JKingWeb\Arsse\User\Exception as UserException;
 
 class OPML extends AbstractImportExport {
-    public function parse(string $opml, bool $flat): array {
+    protected function parse(string $opml, bool $flat): array {
         $d = new \DOMDocument;
         if (!@$d->loadXML($opml)) {
             // not a valid XML document
diff --git a/tests/cases/ImportExport/TestOPML.php b/tests/cases/ImportExport/TestOPML.php
index 0002f2c8..e4ef7b42 100644
--- a/tests/cases/ImportExport/TestOPML.php
+++ b/tests/cases/ImportExport/TestOPML.php
@@ -109,7 +109,8 @@ OPML_EXPORT_SERIALIZATION;
     /** @dataProvider provideParserData */
     public function testParseOpmlForImport(string $file, bool $flat, $exp) {
         $data = file_get_contents(\JKingWeb\Arsse\DOCROOT."Import/OPML/$file");
-        $parser = new OPML;
+        // set up a partial mock to make the ImportExport::parse() method visible
+        $parser = \Phake::makeVisible(\Phake::partialMock(OPML::class));
         if ($exp instanceof \JKingWeb\Arsse\AbstractException) {
             $this->assertException($exp);
             $parser->parse($data, $flat);