You Need CodeRush

Oops

The other day, I was chatting with some developers and one of them pulled me over to show me the following code:

private void SetLayout(Page page)
{
    if (null == page)
    {
        return;
    }
}

I did a double take and then smirked a bit, pointing out that this was probably dead code. I asked the person who was showing me this to do a “find all references” and there actually was one:

private void mainFrameNavigated(object sender, System.Windows.Navigation.NavigationEventArgs e)
{
    Page page = e.Content as Page;
    if (page != null)
    {
        SetLayout(page);
    }
}

So, we then backed it up a step and discovered that this was an event handler for an event declared in XAML (this whole thing was in a code-behind file). So, every time some event occurred (some sort of navigation thing), the code would cast the sender as a page, call a method with that page, and then return if the page was null, and also return if the page wasn’t null.

How Did It Come To This?

Looking at the SetLayout method, I quickly developed a hypothesis as to how the code wound up this way. The “SetLayout” method probably checked the page for null as a precondition prior to performing some sort of action on Page. At some point, that action became undesirable and was removed from the code, but whoever removed it didn’t realize that the precondition check was now meaningless, as was the whole chain of code above it for the event handler. This was confirmed correct by a quick glance through source control.

Here’s what this looks like in my IDE:

Do you see the dashes on the right, next to the scroll bar? Those are the issues in the CodeRush “issues list”. Do you see the squiggly underline of “SetLayout” (hard to see at this resolution, but you can zoom in or open the image in a new tab if you want)? That means there’s an issue here. In the interests of full disclosure, this is actually to tell me that the method could be static (it operates on no instance member of the class) rather than to tell me that the method has no effect on anything, but the important thing is that it’s underlined. It draws my attention to the method instead of encouraging me to skip over it while looking for something else here. And, as soon as this method catches anyone’s attention, it will obviously be deleted.

The Value of Productivity Tools

In general, the Code Rush issues list is a great companion. It alerts me to dead code, undisposed disposables, redundant statements, and plenty of other things. If you pause any time it tells you about an issue, you will become better at programming and you will start to recognize more problems. It isn’t necessarily superior to using, say, Style Cop or any other particular tool, but it is very convenient in that it paints the problems right inline with the IDE. They’re quite noticeable.

Code Rush’s competitor, Resharper does this as well. I plug for Code Rush because I use it and I love it, but if you get Resharper, that’s fine — just get something. These productivity tools are game changers. When looking at this code in someone else’s IDE, there was no squiggly and no immediately obvious problem if you’re casually scrolling through the class. But in my IDE, my eyes are drawn right to it, allowing and in fact demanding that I fix it. This sort of boy-scouting makes you better at writing your own code and better at fixing other people’s.

I forget what the license costs, but your employer can afford it. Heck, if they’re too cheap, you can afford it. Because what you can’t afford is to have code checked in under your name that looks like the code in this post. That’s no good, and it’s avoidable.

  • http://twitter.com/DMartin_3 Dan Martin

    Finding and removing code like that is such a joy. I especially like when I’m in some old code and see all the unused variables grayed out for me to remove. I use ReSharper, but having either tool will definitely help locate useless/dead code.

  • http://www.daedtech.com/blog Erik Dietrich

    I definitely agree about it being a joy. I keep a garden, and it reminds me of yanking weeds out of the garden. There’s a certain satisfaction to reducing the amount of noise and looking at the end result being simpler and less cluttered.

  • Pingback: Productivity Add-Ins: Bruce Lee vs Batman | DaedTech