PDFBOX-5660: improve test coverage

git-svn-id: https://svn.apache.org/repos/asf/pdfbox/trunk@1927892 13f79535-47bb-0310-9956-ffa450edef68

Author: THausherr

pdfbox/src/test/java/org/apache/pdfbox/multipdf/PDFCloneUtilityTest.java

@@ -61,7 +61,9 @@ void testClonePDFWithCosArrayStream() throws IOException
             srcDoc.addPage(pdPage);
             new PDPageContentStream(srcDoc, pdPage, AppendMode.APPEND, true).close();
             new PDPageContentStream(srcDoc, pdPage, AppendMode.APPEND, true).close();
-            COSDictionary clonedPageDictionary = new PDFCloneUtility(dstDoc).cloneForNewDocument(pdPage.getCOSObject());
+            PDFCloneUtility cloner = new PDFCloneUtility(dstDoc);
+            assertEquals(dstDoc, cloner.getDestination());
+            COSDictionary clonedPageDictionary = (COSDictionary) cloner.cloneForNewDocument(pdPage.getCOSObject());
             PDPage clonedPage = new PDPage(clonedPageDictionary);
             Iterator<PDStream> contentStreams = clonedPage.getContentStreams();
             assertNotNull(contentStreams.next());