Unit testing is very important procedure in the project and must be used for all modules. It has two major advantages for us. The fist is improving quality of the application from the beginning of development. Correctly written unit tests, based on assumed logic for the component and based on the design, should guarantee that when we integrate independent modules into the bigger ones they will work almost perfectly. There will not be needed to precisely check all aspects of functionality of the final application. This will be done automatically with regression tracking. Another advantage is more related for developers. Using unit testing there is no need to integrate your component into the product and repeat annoying steps to check that your few lines of code work as expected and haven't broken the product. The only rule here is “keep your tests small and fast”.

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