@Test
public void existentErrorFailTest() {

    TOExecutionResult executionResult = new PomFile(model).relative("/").execution(transformedAppFolder, transformationContext);
    assertEquals(executionResult.getType(), TOExecutionResult.Type.ERROR);
    assertEquals(executionResult.getException().getClass(), TransformationOperationException.class);
    assertEquals(executionResult.getException().getMessage(), "There is already a pom file at /");
}