Friday, May 13, 2005

ThoughtBlog

Adewale Oshineye sent me an email because there was a link from my profile page on ThoughtWorks linking to this blog, to ask me if I want to add mine to the ThoughtBlog. The reason that I have not done it is because I want to start publishing this blog only when I really know what kind of blog I am going to keep here, or even if I think it is worth it to keep a blog about my experience in ThoughtWorks.

But I figure, help is already here it really does not make sense to turn it down so I replied yes. Then I figure it is time to subscribe to the blog feed to see what my fellow ThoughtWorkers are writing about, especially with ThunderBird it is so easy.

So already I have learned something new today! I thought I have known all that is to know about writing assertions (assertEquals, assertNotEquals, assertTrue, assertFalse, simple, eh?). Boy was I wrong. Joe's blog "Flexible JUnit assertions with assertThat()" sure opened up my eye.

When I was working for JBuilder, I wrote a test framework for unit-testing some part of JBuilder modules. When a test fail, it is always desirable to see as much information as possible in the error message regarding information like project configuration, run configuration, etc. However, JUnit requires you to provide a message before the assertion happens, which means that all the tests will need to spend a lot of time constructing the messages, even though they might not be needed. So I wrote this LazyAssert that only constructs the message if the assertion fails, and ended up duplicating a lot of Assert APIs. I was quite bugged by that result but concluded that there was nothing I can do.

And now I know the right way.

My hats off to Joe for sharing it with us. And again to my fellow ThoughtWorkers.

Update of an example:

Check this out:

before:
junit.framework.AssertionFailedError
...(Click for full stack trace)...
at com.company.product.person.dao.jdbc.JDBCAffiliationDAOTest.testInsertAffiliation(JDBCAffiliationDAOTest.java:92)
...
at org.jmock.core.VerifyingTestCase.runBare(Unknown Source)
...


after:
junit.framework.AssertionFailedError:
Expected: timestamp is after 2005-05-16 15:21:34.871
but got : Mon May 16 15:21:34 PDT 2005

...(Click for full stack trace)...
at com.company.product.test.BaseAsserts.assertThat(BaseAsserts.java:31)
at com.company.product.test.BaseAsserts.assertThat(BaseAsserts.java:23)
at com.company.product.person.dao.jdbc.JDBCAffiliationDAOTest.testInsertAffiliation(JDBCAffiliationDAOTest.java:93)
...
at org.jmock.core.VerifyingTestCase.runBare(Unknown Source)
...
Post a Comment