Koodihommia

I write a lot of stupid and useless unit tests. I confess that I'm aiming towards the elusive 100% test coverage. Sure, I'll never get there, and I realize it is not even a desirable goal. After an assessed threshold, we start to get diminishing returns. Why do I keep writing wrong tests then? Which unit tests should I leave out? My case is that it is tricky to write a large codebase with only valuable tests. I dare say that some (minority) of the essential tests might have outright bad practices where they end up testing how well I can mock stuff. The value of the test is not predetermined; hence I keep writing a lot of seemingly poor ones. There is an argument that high test coverage does not strongly reduce bugs and increase maintainability. That is likely true. Nonetheless, it is not so apparent which tests will avoid the most bugs or are the most useful in refactoring in the long term. The cliché is that requirements change, sometimes towards unknown directions.  It is mor...

I have experienced a lot of issues with UI testing with Vaadin and Selenium. The test cases might seem to run OK initially but turn out very easily to be unstable, especially if the machine running tests is much faster/slower than the machine the tests have been written. The setups I have used contains some version of selenium, Robot framework, jBehave or CasperJS and PhantomJS, Chrome or Firefox. I haven't used the Vaadin Testbench. Here are my five cents to create stable Vaadin UI tests. Don't use the in-built "is page loaded" methods, those rarely apply to single page JS apps. Use the JS object "vaadin" and its properties isActive() and initialized to determine when it is OK to modify the UI. Run in production mode, I have had a lot fewer issues like this. Capture the browser logs, filter out there all info category messages and see if there are errors. Use xpaths to find the correct elements. I have noticed that it helps if you wait first for some...