Let a slow provider do its work, in an embedded server, perhaps (FTPS
for example).
diff --git a/commons-vfs2/src/test/java/org/apache/commons/vfs2/ProviderDeleteTests.java b/commons-vfs2/src/test/java/org/apache/commons/vfs2/ProviderDeleteTests.java
index 01de8f3..5def6b9 100644
--- a/commons-vfs2/src/test/java/org/apache/commons/vfs2/ProviderDeleteTests.java
+++ b/commons-vfs2/src/test/java/org/apache/commons/vfs2/ProviderDeleteTests.java
@@ -113,7 +113,12 @@
     public void testDeleteAllFiles() throws Exception {
         final FileObject scratchFolder = createScratchFolder();
 
-        assertEquals(2, scratchFolder.delete(new FileTypeSelector(FileType.FILE)));
+        final int deleteCount = scratchFolder.delete(new FileTypeSelector(FileType.FILE));
+        if (deleteCount < 2) {
+            // Slow deletion in an embedded server perhaps (FTPS for example). 
+            Thread.sleep(500);
+        }
+        assertEquals(2, deleteCount);
     }
 
     /**