Handling exclude_paths in reek configuration

[abhinavmsra]

Acknowledgement

I love danger & its plugin gems. They are always a part of my CI suite. I would like to express my gratitude to the maintainers of this project. 👏👏👏

Current Behavior

Danger::DangerReek

def lint
  files_to_lint = fetch_files_to_lint
  code_smells   = run_linter(files_to_lint)
  warn_each_line(code_smells)
end

Step Analysis

1. Builds a file list to examine, basically all changed files

fetch_files_to_lint = git.modified_files + git.added_files

2. Builds an examiner object for each files & evaluates it's smells.

run_linter(files_to_lint)

def run_linter(files_to_lint)
  configuration = ::Reek::Configuration::AppConfiguration.from_path(nil)
  files_to_lint.flat_map do |file|
    examiner = ::Reek::Examiner.new(file, configuration: configuration)
    examiner.smells
  end
end

examiner = ::Reek::Examiner.new(file, configuration: configuration)

This examiner does not check if the file path is in exclude_paths on Reek configuration. And as such, posts warning messages on PR.

Issue

exclude_paths is .reek.yml has no effect.

exclude_paths:
  - db/migrate

It gets particularly annoying if you add migration files. It posts FeatureEnvy message on each files.

Refers to 't' more than self

Proposed Enhancement

I made it work with the following change:

module MyDanger
  module ReekDecorator
    private

    def fetch_files_to_lint
      files = git.modified_files + git.added_files
      excluded_files = files.to_a.select { |file| file_excluded?(file) }
      files_to_lint = files - excluded_files
      ::Reek::Source::SourceLocator.new(files_to_lint).sources
    end

    def file_excluded?(filename)
      configuration = ::Reek::Configuration::AppConfiguration.from_path(nil)

      configuration.send(:excluded_paths).map(&:expand_path).map do |excluded_path|
        Pathname(filename).expand_path.fnmatch?(File.join(excluded_path, '**'))
      end.any?
    end
  end
end

Danger::DangerReek.prepend(MyDanger::ReekDecorator)

• It basically modifies fetch_files_to_lint method to discard files in excluded_paths path

It would be great to have some community feedback on this.

I can create a PR if my proposed solution is agreeable.