class RuboCop::Cop::RSpec::NamedSubject

Checks for explicitly referenced test subjects.

RSpec lets you declare an “implicit subject” using `subject { … }` which allows for tests like `it { is_expected.to be_valid }`. If you need to reference your test subject you should explicitly name it using `subject(:your_subject_name) { … }`. Your test subjects should be the most important object in your tests so they deserve a descriptive name.

This cop can be configured in your configuration using the `IgnoreSharedExamples` which will not report offenses for implicit subjects in shared example groups.

@example

# bad
RSpec.describe User do
  subject { described_class.new }

  it 'is valid' do
    expect(subject.valid?).to be(true)
  end
end

# good
RSpec.describe Foo do
  subject(:user) { described_class.new }

  it 'is valid' do
    expect(user.valid?).to be(true)
  end
end

# also good
RSpec.describe Foo do
  subject(:user) { described_class.new }

  it { is_expected.to be_valid }
end

Constants

MSG

Public Instance Methods

ignored_shared_example?(node) click to toggle source
# File lib/rubocop/cop/rspec/named_subject.rb, line 68
def ignored_shared_example?(node)
  cop_config['IgnoreSharedExamples'] &&
    node.each_ancestor(:block).any?(&method(:shared_example?))
end
on_block(node) click to toggle source
# File lib/rubocop/cop/rspec/named_subject.rb, line 58
def on_block(node)
  if !example_or_hook_block?(node) || ignored_shared_example?(node)
    return
  end

  subject_usage(node) do |subject_node|
    add_offense(subject_node.loc.selector)
  end
end