diff --git a/lib/Test/MockFile.pm b/lib/Test/MockFile.pm
index 57b972f..c16f30c 100644
--- a/lib/Test/MockFile.pm
+++ b/lib/Test/MockFile.pm
@@ -846,7 +846,7 @@ sub dir {
     # TODO: Add stat information
 
     # FIXME: Quick and dirty: provide a helper method?
-    my $has_content = grep m{^\Q$path/\E}xms, %files_being_mocked;
+    my $has_content = grep m{^\Q$path/\E}xms, keys %files_being_mocked;
     return $class->new(
         {
             'path'        => $path,
diff --git a/t/opendir.t b/t/opendir.t
index 6370d1d..af0e5f9 100644
--- a/t/opendir.t
+++ b/t/opendir.t
@@ -99,5 +99,21 @@ is(
     is( \@content, [qw< . .. bar >], 'Did not get confused by internal files' );
 }
 
+# Regression: dir() must use "keys" when grepping %files_being_mocked.
+# Without "keys", grep iterates over both keys (paths) and values (weakrefs
+# to blessed hashrefs). The stringified mock objects could accidentally match
+# the path regex, inflating has_content or causing uninitialized-value warnings
+# when weakrefs are cleared during global destruction.
+{
+    my $mock_file = Test::MockFile->file( '/regdir/somefile', 'data' );
+    my $mock_dir  = Test::MockFile->dir('/regdir');
+
+    is( $mock_dir->contents(), [qw< . .. somefile >], 'dir() detects mocked child file via keys %files_being_mocked' );
+
+    opendir my $dh, '/regdir' or die "opendir /regdir: $!";
+    is( [ readdir($dh) ], [qw< . .. somefile >], 'readdir returns correct entries for dir with mocked children' );
+    closedir $dh;
+}
+
 done_testing();
 exit;