A common anti-pattern is the "expanded conditional". You know the drill:

if (a == b && b != c)
{
    return true;
} else {
    return false;
}

This could be condensed into a single return statement. It's annoying, and stupid, and frequently part of a WTF, but never a WTF in-and-of-itself.

Except for this one, found by Timo.

// check if the IDs match
public bool CheckIfIdMatch(int currentProductId, int foundProductId)
{
    // if the product matches with the target
    if (currentProductId == foundProductId)
    {
        // return true
        return true;
    }

    // else, return false
    return false;
}

This is a perfect block of bad code. It takes a simple task (an equality comparison between integers) and stretches it out to a whole block of code with an expanded conditional. The comments are useless restatements of the code itself. And of course, it's such a "useful" method, it's invoked in all sorts of places throughout the code.

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