}
@Test
public void identicalS4() {
topLevelContext.getGlobalEnvironment().setVariable("x", new S4Object());
topLevelContext.getGlobalEnvironment().setVariable("y", new S4Object());
eval("attr(x, 'foo') <- 'bar' ");
eval("attr(y, 'foo') <- 'baz' ");
assertThat(eval(".Internal(identical(x,y,TRUE,TRUE,TRUE,TRUE))"), equalTo(c(false)));