diff --git a/test/unit/validator/sfValidatorFileTest.php b/test/unit/validator/sfValidatorFileTest.php
index 6d9f524b2..54b1d5e10 100755
--- a/test/unit/validator/sfValidatorFileTest.php
+++ b/test/unit/validator/sfValidatorFileTest.php
@@ -90,7 +90,7 @@ public function getMimeTypesFromCategory($category)
 $v = new testValidatorFile();
 $t->is($v->guessFromFileBinary($tmpDir.'/test.txt'), 'text/plain', '->guessFromFileBinary() guesses the type of a given file');
 $t->is($v->guessFromFileBinary($tmpDir.'/foo.txt'), null, '->guessFromFileBinary() returns null if the file type is not guessable');
-$t->like($v->guessFromFileBinary('/bin/ls'), (PHP_OS != 'Darwin') ? '/^application\/x-(pie-executable|executable|sharedlib)$/' : '/^application/octet-stream$/', '->guessFromFileBinary() returns correct type if file is guessable');
+$t->is($v->guessFromFileBinary(PHP_BINARY), 'application/x-pie-executable', '->guessFromFileBinary() returns correct type if file is guessable');
 $t->is($v->guessFromFileBinary('-test'), null, '->guessFromFileBinary() returns null if file path has leading dash');
 
 // ->getMimeType()