copilot – stlplace

I learned a bit more GitHub Copilot recently

Reading Time: 2 minutes

I worked on a small project (in the Agile or JIRA world, it’s a story), and I experimented Copilot more this time, in fact, I think I tried to use Copilot as much or as practically as possible, for 2 out of the 3 main coding tasks. This is in addition to the Copilot code review feature which I have been using probably for a year now. Back to the coding tasks: refactoring and adding unit tests are the two main tasks that I used Copilot extensively. I also think Copilot did a decent job on bath. The 3rd task, which is to create a controller (an end point), I forgot to try the Copilot – hope I can try something like that down the road.

I used the IntelliJ Ultimate edition for my Java project IDE, and I was familiar with some IDE basic features on refactoring, such as extract methods, or change method signature. This mini project involves moving code from one layer down (from UI to the service layer). Copilot did it in one shot when I asked it to perform the task, from and to, mainly using the correct prompt.

For Unit Testing, I did two things, I changed the mocking framework from EasyMock to Mockito (which is more modern), also I added and cleaned all the unit tests, as much as I can. I admit I am still learning on the unit testing front. Sometimes I felt it’s somewhat like “teach an old dog a new trick”, I mean the “test driven development” or writing a complete unit test suite. But I am getting there: not just on Java, for JavaScript, I had some fun writing Jest test as well. For Java it’s JUnit.

Code review

This is similar as before I worked on this mini project, but I am getting more out of the Copilot code review comments, most of which I think is valid.

On a side note, I did a coding test for this LinkedIn AI trainer gig – not sure that I passed it, as I was not very confident on my Python language. But I still think it’s good exercise for me – I mean the coding test via HackerRank.

My impressions on Copilot

Reading Time: 2 minutes

Code Review

At my current work place recently we switched from Atlassian’s Bitbucket (stash) to Microsoft’s GitHub for our source code version control system. Along with that, we get the GitHub Action (which is somewhat like Jenkins, the CI/CD tool) as well as Copilot Code Review and other Copilot tools.

Let me talk about Copilot Code Review first. In general I say it’s pretty good, with its quick human readable overview or summary for the code change. I think it’s probably better than I would write myself: if I ever have to write such a summary.

Now, the code review comments. There are various levels of comments in terms of severity. If you have done any code review, you will probably know quite a bit of suggestions or feedback are subjective, because coding is still not exact science, or like some of the other disciplines such as Mechanical Engineering. I will categorize the comments below:

Nitpick: Copilot actually says that word. We can ignore those.
Format or spacing, we can accept the suggestions, and commit directly. That’s probably the only place we can directly commit.
Other suggestions: I think most are valid. And we should try to incorporate them in our coding. For example: things around better error handling, more robust code, efficiency, break out functions from common code (copy and paste code), and so on. This including feedback on the unit testing too. One thing to keep in mind, always run unit test or debug the code changes before we commit, don’t just commit the code change in the web browser. Because I learned the lesson hard way: I commit code directly, then I realized that I broke the CI (continuous integration) build.

Coding Assistant

My own exp: I have done a bit experiment on this, both via the Copilot inside IntelliJ and VS Code. I will continue use Copilot. Somewhat like code review suggestions: coding assistant (or Q&A) is not AI does the coding for us, we still need to think about the usual stuff: design, testing scenario, debugging, and so on. Again we can think copilot as a colleague or a coworker in pair programming, but we always need to verify in addition to the usual “trust”.

I noticed one approach that one coworker was using. Ask Copilot questions, and use the answers directly, and so on. It seems to me this is a bit like a junior engineer’s approach. And I can see one downside of this approach, see below picture, original source: this is a joke but it has some truth.

I have done similar things in the past, except before all the AI tools, I was mostly googling, including using answers from stackoverflow.