Writing many tests to test one method

[Swerrgy Smith]

Hi all,

Suppose I want to test the method doSomething() of the class Biz; I create a test class BizTest.
If I want to write many test methods to test doSomething(), how should I name these methods? I am thinking of some thing like: testDoSomething_1(), testDoSomething_2() ... but it will look like a automatically generated test (and not a test written by a person); furthermore, it will not tell the nature of each test (e.g. what the test method testDoSomething_1() is supposed to do).

What do you think about that? Or should I write only 1 method testDoSomething() and put a lot of assertxxxx inside?

Thanks for your advice.

[Gregg Bolinger]

You should name your test methods based on what you're attempting to assert. For example, suppose your class Biz has a method called calculateTotal(). You might name your test methods as such:

testCalculateTotalSuccess() { // TODO assert good case }
testCalculateTotalBadInput() { // TODO assert method handles bad input }

Test methods should be as well defined as your methods being tested. testCalculateTotal_xxx is a bad idea.

[Swerrgy Smith]

Gregg Bolinger wrote:You should name your test methods based on what you're attempting to assert. For example, suppose your class Biz has a method called calculateTotal(). You might name your test methods as such:

testCalculateTotalSuccess() { // TODO assert good case }
testCalculateTotalBadInput() { // TODO assert method handles bad input }

Test methods should be as well defined as your methods being tested. testCalculateTotal_xxx is a bad idea.

Thanks for your excellent advice, Gregg.

[Junilu Lacar]

If you're using JUnit 4 you can make your test names even better by removing "test". I use a convention based on Neal Ford's suggestion for test names (Slide 44, http://www.slideshare.net/guestebde/10-ways-to-improve-your-code-neal-ford):

    @Test
    public void calculateTotal_is_zero_when_no_items()

    @Test
    public void calculateTotal_is_nonzero_when_one_or_more_items()

    @Test
    public void calculateTotal_is_blah_when_blah_blah()

    @Test
    public void calculateTotal_throws_SomeException_when_blah()

    @Test
    public void calculateTotal_yada_yada_yada()

With a little effort to arrange and name your test methods with some consistency, the test report can read very nicely