@Test
public void testInsertStmt() {

  BlockStmt b = new BlockStmt(Arrays.asList(new NullStmt()), true);
  assertEquals(1, b.getNumStmts());
  b.insertStmt(0, new ExprStmt(new BoolConstantExpr(true)));
  assertEquals(2, b.getNumStmts());
  assertTrue(((BoolConstantExpr) ((ExprStmt)b.getStmt(0)).getExpr()).getIsTrue());
  assertTrue(b.getStmt(1) instanceof NullStmt);
}