A review of GitHub Copilot

I’ve been using GitHub Copilot for Unity development and it is incredible. It has saved me from tons of bugs, speeded up my work by 2x, and even taught me a lot of C# (which Unity uses and I haven’t used before).

How does it work? You install it as a VS Code extension and then, as you type, it (very magically) suggests what should come next. For example, I have a very simple utility class with a static field, WorldWidth, to get the size of the screen in world coordinates. Suppose I wanted to add a WorldHeight field. I press enter, and I literally don’t even have to start typing:

It knows that this is the other function I’d likely want.

Okay, but that’s very simply. How about something more complex? This is a long function, so excerpting part of it, but it’s a nested for loop that looks at each column on the game board.

At the end of this function, I press enter and:

Note that bool lastIter went from y == board[x].Length - 1 to board.Length - 1. Fancy!

Its context-awareness is also great when you don’t want to have to look up math formulas:

(…it works for much more complicated math, too.)

And it saves tons of time writing out annoying debugging messages or ToString functions:

It also taught me C#’s $-formatting and rolls with other formats as you go, e.g., if you prefer (x,y) format.

The downside of using this is that I’m much more likely to repeat code, because I don’t have to write it all out. For example, in the GetVerticalRuns/GetHorizontalRuns functions above, I probably would have pulled out the loops into a common function if I had to write it myself. However, I also probably would have messed it up on the first try.

If you do any programming, I highly recommend signing up for Copilot. It takes away a lot of repetitive, annoying, and route work and lets you concentrate on actually getting your project working.