fest-assert-2.x
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Varargs methods produce warnings for generic parameters
List<Integer> list1 = new ArrayList<Integer>();
List<Integer> list2 = new ArrayList<Integer>();
List<Integer> list3 = new ArrayList<Integer>();
List<List<Integer>> listOfLists = new ArrayList<List<Integer>>();
listOfLists.add(list1);
listOfLists.add(list2);
listOfLists.add(list3);
assertThat(listOfLists).contains(list1, list2, list3); // Type safety: A generic array of List<Integer> is created for a varargs parameter
This problem can be solved by overloading a varargs method with a different number of arguments:
public S contains(T value1) { ... }
public S contains(T value1, T value2) { ... }
public S contains(T value1, T value2, T value3) { ... }
public S contains(T value1, T value2, T value3, T value4) { ... }
...
This technique is used, for example, in Guava: http://code.google.com/p/guava-libraries/source/browse/guava/src/com/google/common/collect/ImmutableList.java
The problem is that the vararg takes an array of T, where it should just an array of Object. For tests it really doesn't matter type safety in the vararg. A failing test will tell the user that something is wrong.
Wouldn't adding a @SafeVarargs
annotation suffice?