### Question:
DMNDiagramHelper { public Diagram<Graph, Metadata> getDiagramByPath(final Path path) { return diagramService.getDiagramByPath(path); } @Inject  DMNDiagramHelper(final DiagramService diagramService,
                            final DMNDiagramUtils dmnDiagramUtils); List<DRGElement> getNodes(final Diagram diagram); List<ItemDefinition> getItemDefinitions(final Diagram diagram); String getNamespace(final Path path); String getNamespace(final Diagram diagram); Diagram<Graph, Metadata> getDiagramByPath(final Path path);  }### Answer:
@Test public void testGetDiagramByPath() { when(diagramService.getDiagramByPath(path)).thenReturn(diagram); Diagram<Graph, Metadata> actualDiagram = helper.getDiagramByPath(path); assertEquals(diagram, actualDiagram); }