Using css modules the right way, I got it to work. ๐ŸŽ‰ In the end I had some naming clashes where I already tried to prefix my css class names with the module nameโ€”which is handled by css modules already. Because of this duplication it didn’t work. Now it does. Yay!

I am working on my first React component library for my current client. Doing lots of things for the first time. Running into lots of roadblocks and things don’t really work like I expect them to. This might be simple, but it’s not easy.

This morning I took some detours on my way to my client by bike. I rode through some parks, chose small streets and enjoyed myself on my @8barbikes adventure bike. Iโ€˜m very much in love.

From my friend Ian, I learned the value of putting a clear; in front of your test runs in the terminal. Wasn’t aware of the difference it makes for running your tests many times.

Inspecting changes locally before pushing

If you work on your branch you run into the situation that you would like to push your changes to the remote repository. CI will then pick up your changes and run the linting and code quality checks on it. Afterwards, you will see whether you improved the quality. But perhaps there are some new violations that crept into the code? Happens to all of us!

I usually like to see and check if any new issues might come up on CI. This lets me improve them before I push. The checks I run locally depend on the kind of work that I do. Lately that’s a lot of Ruby on Rails again โ€” which is great. I love that framework and the language. To grade my code, I use Rubocop, Reek and Flay. If you run their respective commands on your repository, they will check the whole code base. This might be ok, if you didn’t have any issues before. Since I join teams, these days, that work on legacy projects it is rare that there are no problems with the code. If I run the commands just so, I will get a long list and couldn’t possibly see the issues that I introduced through my changes. Lucikly, there is Git and some “command line foo” that can help us here:

git fetch && git diff-tree -r --no-commit-id --name-only master@\{u\} head | xargs ls -1 2>/dev/null | grep '\.rb$' | xargs rubocop

This command will fetch the current state from the remote and diff your branch/changes to master branch. It then runs rubocop on these changes. In my ~/.aliases.local file I added three lines for all three linters.

# Code Quality
alias rubocop-changes="git fetch && git diff-tree -r --no-commit-id --name-only master@\{u\} head | xargs ls -1 2>/dev/null | grep '\.rb$' | xargs rubocop"
alias reek-changes="git fetch && git diff-tree -r --no-commit-id --name-only master@\{u\} head | xargs ls -1 2>/dev/null | grep '\.rb$' | xargs reek"
alias flay-changes="git fetch && git diff-tree -r --no-commit-id --name-only master@\{u\} head | xargs ls -1 2>/dev/null | grep '\.rb$' | xargs flay"

I am still working on a way to just call one command and have all thee commands run. That doesn’t yet work. Probably because of exit-code reasons, when one linter finds issues.

These simple commands offer a convenient way to find local issues and correct them before pushing to CI.

Avdi Grimm's view on deleting tests

A few weeks ago I wrote about deleting your tests. Yesterday I received the weekly email from Avdi Grimm, where he touches on this subject.

Some premises about my relationship with unit testing:

I like test-driven development. I like driving out individual object design small, isolated (e.g. no database) unit tests. I think of these unit tests as a design aid, full stop. Any help they provide with preventing regressions is gravy. I treat unit tests as disposable. Once they have served their purpose as design aids, I will only keep them around so long as they aren’t getting in the way. These four premises are strongly interconnected. Take away #1 (test first), and tests are no longer a design aid and none of the other points are valid. Take away #2 (isolation) and we get into integration test territory where there’s a much higher possibility of tests having regression-prevention value. Take away #3 (design focus) and the other points lose their justification. Take away #4 (disposability) and I spend all my time updating tests broken code changes.

This makes it easy for me to find myself at cross purposes with others in discussions about unit testing, because often they come into the conversation not sharing my premises. For instance, if your focus in unit testing is on preventing regressions, you might well decide isolated unit tests are more trouble than they are worth. I can’t really argue with that.

A recent conversation on this topic inspired the thought from the driving-design perspective, maybe unit tests are really just a crutch for languages that don’t have a sufficiently strong REPL experience. While I don’t think this is strictly true, I think the perspective shines a useful light on what we’re really trying to accomplish with unit tests. I almost think that what I really want out of unit tests is the ability to fiddle with live objects in a REPL until they do what I want, and then save that REPL session directly to a test for convenience in flagging API changes.

That conversation also spawned the idea of immutable unit tests: unit tests that can only be deleted, never updated. A bit like TCR. I wonder if this would place some helpful incentives on the test-writing process.

You should subscribe to his newsletter, if you haven’t yet.

My submission to Euruko was rejected. โ˜น That’s a pity, would have loved to visit Rotterdam. I still have 7 other proposals that might come through. Fingers crossed ๐Ÿคž

External forces

I am occupied with learning these days. Learning on my own about visualizations of data among other topics. But also learning about learning. For that I read what other people think about learning. There are many things I have to learn about this whole topic. One thought I saw repeatedly, was about external forces, or limiting factors.

Let me elaborate what I mean by that: There are people that can motivate themselves more easily than others can. They reach their goals or at least try very hard. Others give up more easily when they face some resistance. As always, there are people in the middle between these extremes. You know best which group you belong to. ๐Ÿ’ช

What has this do with software quality? I am getting thereโ€ฆ ๐Ÿ˜‰

I am wondering how external forces could help improve quality. If you need to reach your goal and you don’t belong to the group of highly self-motivated people there are options like hiring a coach. Athletes do that all the time. I pay for a “virtual” coach that guides my running efforts.

How could you hire a “virtual” coach for your coding efforts, for reaching your targets on your software quality metrics? You could hire me or other “real” coaches, of course. But that doesn’t scale too well and might be too expensive.

Again, for some people it is easy enough to use static analysis or linting โ€” a kind of coach in it’s own right โ€” and follow their guidelines. Yet, still there are people that ignore the warnings or guidelines imposed upon them by the tools. Reasons may be a hard deadline or too much workload. How could we offer external forces, limiting factors that help them, guide them, towards doing the right thing?

One solution I can think of is to have a robot not accept your code when it is below standard or ignores guidelines. A robot could be anything that measures and grades your code and reports back to your team. Some tools already offer this, for example GitLab. If you want to merge code that decreases the overal quality metrics, you are not allowed to do so. So that would be one.

Another idea: If you try to commit or merge such code, you need to consult with another developer about the code. Once you worked on it together, the other dev has to enter her secret key, to remove the lock on the merge. This forces you to pair on code more often.

When it comes to teaching there is this saying of the “glass has to be empty (enough).” You cannot pour water into it, when it’s already filled. Said ideas ๐Ÿ‘†probably won’t work for a team that isn’t aiming for learning and improving.

I will continue to think.

You probably know AC/DC. But have you heard of MC/DC?

If you need to test a complex conditional, you should take some time to learn about this one.

holgerfrohloff.de/newslette…

Today I am working on a new visualization of fragmentation of ownership for Git repositories. The more fragmented a repo is, the more developers work on it together. This leads to no clear ownership and makes it easier for defects to creep into the code.