assertEquals("[3, 3]", Arrays.toString(hidden.get(0)));
assertEquals("[5, 5]", Arrays.toString(hidden.get(1)));
// hiding column 4 expands [3, 3] to [3, 4]
// and merges to [5, 5] to make [3, 5]
colsel.hideSelectedColumns(4, al.getHiddenColumns());
assertEquals("[3, 3]", Arrays.toString(hidden.get(0)));
assertEquals("[5, 5]", Arrays.toString(hidden.get(1)));
// hiding column 4 expands [3, 3] to [3, 4]
// and merges to [5, 5] to make [3, 5]
colsel.hideSelectedColumns(4, al.getHiddenColumns());