22nd April, 2020 Output.
Overview
RuboCop is a Ruby source code analysis tool that automatically checks if your code conforms to the Ruby style guide from the Ruby community (English/Japanese), or other style guides (such as MeowCop, which our company provides). It focuses on enforcing Rails best practices and coding conventions.
Advantages
It indicates the project coding rules.
By using Rubocop to keep the codes clean, you’ll have fewer mistakes and it leads to effective review.
Installation
Just install the rubocop gem
gem install rubocop
or if you use bundler put this in your Gemfile
gem 'rubocop', require: false
How to write .rubocop.yml file
By placing the configuration file .rubocop.yml in the root directory of the project, RuboCop will read this automatically. Or it can also specify a yml file in any location as a configuration file by -c option.
Below are the representative codes in .rubocop.yml file.
Specify the file to exclude from RuboCop
Use Exclude: to exclude files like (db/schema.rb) which is automatically generated by Rails,
or gem placed under vendor/bundle from RuboCop.
For example, use the following to exclude the db/schema.rb file from RuboCop.
AllCops:
Exclude:
- db/schema.rb
Enabling/Disabling Cop (Enabled: false/true)
When you feel a certain cop isn’t suitable for the project, you can disable it individually.
Style/TrailingComma:
Enabled: false
Reference