Module: Moarspec::Its::Call

Defined in:
lib/moarspec/its/call.rb

Instance Method Summary collapse

Instance Method Details

#its_call(*args, **kwargs, &block) ⇒ Object

For ‘#call`-able subject, creates nested example where subject is called with arguments provided, allowing to apply block matchers like `.to change(something)` or `.to raise_error` to different calls in a DRY way.

Also, plays really well with #ret block matcher.

Examples:

let(:array) { %i[a b c] }

describe '#[]' do
  subject { array.method(:[]) }

  its_call(1) { is_expected.to ret :b }
  its_call(1..-1) { is_expected.to ret %i[b c] }
  its_call('foo') { is_expected.to raise_error TypeError }
end

describe '#push' do
  subject { array.method(:push) }
  its_call(5) { is_expected.to change(array, :length).by(1) }
end


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# File 'lib/moarspec/its/call.rb', line 28

def its_call(*args, **kwargs, &block)
  # rubocop:disable Lint/NestedMethodDefinition
  describe("(#{args.map(&:inspect).join(', ')})") do
    let(:__call_subject) do
      subject.call(*args, **kwargs)
    end

    def is_expected
      expect { __call_subject }
    end

    example(nil, &block)
  end
  # rubocop:enable Lint/NestedMethodDefinition
end