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javajunithamcrest

AssertEquals when list content is unordered

How would you refactor the following if the products can be returned in any order?

List<Product> products = get_products("test_produc");
assertEquals(products.size(),3);
assertEquals(products.get(0).getName(), "test_product1");
assertEquals(products.get(1).getName(), "test_product2");
assertEquals(products.get(2).getName(), "test_produc3");

If it can be done elegantly using streams then I'm oopen to such suggestions. Hamcrest suggestions are also welcome.

Solution

  • Note that assertEquals also works on Lists and Sets directly. This is much less typing and it will give very clear error messages.

    If the return values are not allowed to contain duplicates, they should return a Set instead of a List. If you can change the function you are testing is this way you can test it as follows:

    assertEquals(new HashSet<>(Arrays.asList("Item1", "Item2")), get_products());

    If this is not an option you should sort both the expected and the actual results and compare those:

    asssertEquals(Arrays.sort(Arrays.asList("Item1", "Item2")), Arrays.sort(get_products()));

    Finally you could resort to using Hamcrest matchers (the function containsInAnyOrder is in org.hamcrest.collection.IsIterableContainingInAnyOrder):

    assertThat(get_products(), containsInAnyOrder("Item1", "Item2"));