Assertion is a statement in your code that checks if a condition is true, otherwise it throws an error faster than Elon Musk changes his mind on Twitter. It's like a bouncer at a nightclub, making sure only the right values get in, so your program doesn't end up like FTX.

How to use it in a sentence

• "I added an assertion to check if the user input is valid, because apparently, some people think 'password123' is still a secure password in 2023."

• "The QA team keeps finding bugs in my code, so I sprinkled some assertions around like fairy dust, hoping it will magically fix everything before the next sprint review."

If you actually want to learn more...

• Assertion-Free Testing: Martin Fowler explains how writing tests without assertions is like having a project manager who just nods and smiles without actually checking if anything works. Read more

• Testing Asynchronous JavaScript: Pete Hodgson dives into how promise-based async code can be tested cleanly, for those times when you need to assert that your Node.js backend won't collapse like a house of cards. Read more

• Modern Mocking Tools and Black Magic: Brett L. Schuchert explores the pros and cons of modern mocking tools, which can help you test legacy code, but might also tempt you to the dark side. Read more

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