# Week 4 - CircuitVerse@GSOC'23

This week was interesting and frustrating at the same time. The maximum time went to explore solutions and resolving the issues with specific library packages. This time everything does not go as planned.

The scheduled task for this week was

* Write RBS Annotations for the codebase
    

### RBS

**What is RBS?**

RBS is a type annotation system introduced in the Ruby programming language. Its purpose is to bring static typing capabilities to Ruby code. We can verify the type signature by using various tools like \[steep, rbs, etc.\]

RBS is released officially by Ruby.

**Interesting Features**

* *Type Safety:* RBS helps catch type-related errors early, improving code reliability.
    
* *Tooling Support:* Static type information enables advanced code editors to offer autocompletion and accurate error detection, enhancing developer productivity.
    
* *Documentation and Readability:* RBS annotations serve as documentation, making code easier to understand and maintain.
    

**Setup**

* Install `rbs_rails` gem
    
    ```bash
    gem install rbs_rails
    ```
    
* Generate tasks
    
    ```bash
    bin/rails g rbs_rails:install
    ```
    
* Run this to generate the rbs collection configuration file
    
    ```bash
    bundle exec rbs collection init
    ```
    
* Now simply run this to download the required gem's rbs file
    
    ```bash
    bundle exec rbs collection install
    ```
    
* We are going to use `steep` gem to type checking
    
* So, install `steep` gem
    
    ```bash
    bundle install steep
    ```
    
* Create `Steepfile` with this configuration
    
    ```bash
    target :app do
      signature "sig"
    end
    ```
    
* As per the configuration, it will check sig folder for our writer rbs annotation files for our codebase
    

**Issues**

But one problem with RBS is -> As it's fairly new to the market, there is not much support for RBS in all the libraries. So we face various issues regarding that.

In our case, while using `rbs validate` it was throwing `RBS::DuplicatedMethodDefinitionError` due to conflicting rbs code of `meta-tags` and `activesupport` gem.

After searching for various solutions and taking suggestions from the maintainer, the final solution to fix the issue was -

* Add `meta-tags` gem to ignore the list of rbs collection configurations like
    
    ```bash
    gems:
      # Skip loading rbs gem's RBS.
      # It's unnecessary if you don't use rbs as a library.
      - name: rbs
        ignore: true
      - name: steep
        ignore: true
    ```
    
* Copy the rbs file of `meta-tags` gem
    
* Modify them to remove duplicate definition issue
    
* And then copy-paste those files in `sig/vendor/meta-tags` folder
    

**References -**

Discussion Thread for the issue - [https://github.com/ruby/rbs/issues/1359](https://github.com/ruby/rbs/issues/1359)

PR - [https://github.com/CircuitVerse/CircuitVerse/pull/3807/](https://github.com/CircuitVerse/CircuitVerse/pull/3807/)

### Undercover CI

Undercover is a great tool to analyze untested code of a commit and do PR reviews.

SimpleCov is mainly used to generate the test details and undercover analyze the generated Lcov file.

**Setup SimpleCov to generate the Lcov file**

* Install `simplecov` and `simplecov-lcov` gem to `:test` group
    
* In the `config/environments/test.rb` file, paste this configuration file at the top
    
    ```ruby
    require "simplecov"
    require "simplecov-lcov"
    SimpleCov::Formatter::LcovFormatter.config.report_with_single_file = true
    SimpleCov.formatter = SimpleCov::Formatter::LcovFormatter
    SimpleCov.start do
      add_filter(/^\/spec\//) # For RSpec, use `test` for MiniTest
      enable_coverage(:branch)
    end
    ```
    
* Now we need to load all the code beforehand for this analysis
    
* So, mark `config.eager_load` = true in configuration of test environment
    
* Now when we run our test suite, it will generate lcov file under `coverage/lcov/<project_name>.lcov` file.
    

**Now, We need to setup undercover CI for PR review**

The first and easier option is to use [https://undercover-ci.com/](https://undercover-ci.com/) which has simple steps for installation. But the issue here is , it's paid for organization

So,we keep searching and found a opensource project [undercover-checkstyle](https://github.com/aki77/undercover-checkstyle) which can review the PR by using `undercover` CLI tool and use [reviewdog](https://github.com/reviewdog/reviewdog) to do the PR Review

For this, add `undercover-checkstyle` gem under `:test` group in Gemfile

In the CI workflow add this configuration

```yaml
- uses: aki77/delete-pr-comments-action@v1
  with:
   token: ${{ secrets.GITHUB_TOKEN }}
   bodyContains: "[undercover]"
   noReply: "true"
- name: Run reviewdog
  env:
    REVIEWDOG_GITHUB_API_TOKEN: ${{ secrets.github_token }}
  run: |
    git fetch --no-tags
    reviewdog -reporter=github-pr-review -runners=undercover --fail-on-error
```

After the setup, it will provide a review of any PR.

Just for example, the `github-actions bot` will give a review like this. *This will also delete previous comments to make the PR Review clean.*

![](https://cdn.hashnode.com/res/hashnode/image/upload/v1687600399601/68dd1e9b-5aac-4b1d-82a3-14fd4b049ff5.png align="center")

PR - [CircuitVerse/CircuitVerse#3812](https://github.com/CircuitVerse/CircuitVerse/pull/3812) [CircuitVerse/CircuitVerse#3818](https://github.com/CircuitVerse/CircuitVerse/pull/3818)

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