Background

So let me start by saying that I come from the world of Java (originally an Android developer, before branching out to do all the other stuff). Which means there's a very rigid idea about how test files are structured back in my world.

Recently I started working on a Golang sample project ¹ and I was told that in Go, typically you keep test files beside your source files. Makes sense, Go's understanding of modules is different from Java's understanding of packages. In Java, when building the test package, the code from main and test are merged semantically keeping the test and the source beside each other in runtime.

Fair enough. Some Javascript projects do the same too - and I am ok doing this.

My Problem with Project Structure

What I do not like though is this type of project structure (file explorer view) by default

- resources
- docs
- src 
    - users 
        - user_controller.go
        - user_controller_test.go
    - articles
        - article_data.go
        - article_data_tests.go
        - article_handler.go
        - article_handler_tests.go

What I would much rather prefer is - at first glance just see all my code.

- resources
- docs
- src 
    - users 
        - user_controller.go
    - articles
        - article_data.go
        - article_handler.go

and then, if I want to look at tests as well, I can expand them and see that as well

Collapsing Test Files

I'll keep it short - you can do this on Jetbrains (Intellij IDEA, Goland etc) as well as Visual Studio Code. I am sure other IDEs have it too - I don't use them - so not my concern for now.

Jetbrains

On JetBrains IDEs the concerned feature we are looking for is called File Nesting

Search for that in the actions bar,

You'll get into this little modal

There is a simple pattern to map there.

If you want all files of type xyz_test.go to be nested under xyz.go then just add this

As you can see, some other patterns, like _string.go and _easyjson.go are already there. These are common Go libraries for JSON parsing and String i18n/l10n which generate such files. I added the _test.go into it.

Now, this is how my src folder looks like by default when I open it

And the tests can be expanded if I want to see them

Visual Studio Code

The same thing can be done for Visual Studio Code. The feature over there is also called File Nesting - we need to go to Settings and enable it first (it is disabled by default).

The file pattern is slightly different here. I have added 2 rules there - one for nesting go.sum file under the go.mod file (I like that Jetbrains Goland does this out of the box). For the other case I write

*.go : ${basename}_test.go

The description in VS Code for that setting (in my above screenshot as well) should be self-explanatory.

And voila, the same thing works on VS Code for now.

References

• [1] https://github.com/championswimmer/onepixel_backend