SOLID. One of the most known abbreviation in programming world. Five rules to rule them all. First question on every interview. About 403 000 000 Google search results for phrase "solid principles" (for comparison for "grasp principles" there are about 72 400 000 results). Knowing SOLID is the first step to transform from junior into regular. It's easy to say - they are popular. Very popular.
Object-oriented languages are very popular. That's a fact. Writing object-oriented code is one of the most popular requirements for developers building enterprise systems. Yet, despite popularity and everyone talking about objects and object-oriented code, I still think many programmers think, that just by writing
classthey make their code OO.
On almost every job interview we can hear this question - "What can you tell me about dependecy injection?". Standard response contains at least one dependency injection framework name and general description with required sentence "it improves testability". Sometimes people say this, without really understandig what it means. How exactly dependency injection improves testability?