ParenExpr extends Expr { @Override public int getNumChildren() { return 1; } ParenExpr(Expr expr); Expr getExpr(); @Override void accept(IAstVisitor visitor); @Override ParenExpr clone(); @Override boolean hasChild(IAstNode candidateChild); @Override Expr getChild(int index); @Override void setChild(int index, Expr expr); @Override int getNumChildren();  }
@Test public void getNumChildren() { assertEquals(1, pe.getNumChildren()); }