Danger Rubocop

A Danger plugin for Rubocop (and compatible wrappers such as Standard).


Add this line to your Gemfile:

gem 'danger-rubocop'


Run Ruby files through Rubocop. Results are passed out as a table in markdown.

Specifying custom config file.


Lint specific files in a folder, when they change

public_files = (git.modified_files + git.added_files).select { |path| path.include?("/public/") }
rubocop.lint public_files

Submit comments only for changed lines

rubocop.lint inline_comment: true

Format using standardrb instead of Rubocop

rubocop.lint rubocop_cmd: 'standardrb'


lint(config: Hash)

Runs Ruby files through Rubocop. Generates a markdown list of warnings.

This method accepts a configuration hash. The following keys are supported:

  • files: array of file names or glob patterns to determine files to lint. If omitted, this will lint only the files changed in the pull request. To lint all files every time, pass an empty string; this is the equivalent of typing rubocop without specifying any files, and will follow the rules in your .rubocop.yml.
  • force_exclusion: pass true to pass --force-exclusion argument to Rubocop. (this option will instruct rubocop to ignore the files that your rubocop config ignores, despite the plugin providing the list of files explicitly)
  • inline_comment: pass true to comment inline of the diffs.
  • fail_on_inline_comment: pass true to use fail instead of warn on inline comment.
  • report_danger: pass true to report errors to Danger, and break CI.
  • config: path to the .rubocop.yml file.
  • only_report_new_offenses: pass true to only report offenses that are in current user's scope. Note that this won't mark offenses for Metrics/XXXLength if you add lines to an already existing scope.
  • include_cop_names: Prepends cop names to the output messages. Example: "Layout/EmptyLinesAroundBlockBody: Extra empty line detected at block body end."
  • rubocop_cmd: Allows you to change the rubocop executable that's invoked. This is used to support rubocop wrappers like Standard by passing standardrb as the value.

Passing files as only argument is also supported for backward compatibility.