Contents

shared_examples_for "an RSpec matcher" do |options|
  let(:valid_value)   { options.fetch(:valid_value) }
  let(:invalid_value) { options.fetch(:invalid_value) }

  it 'preserves the symmetric property of `==`' do
    expect(matcher).to eq(matcher)
    expect(matcher).not_to eq(valid_value)
    expect(valid_value).not_to eq(matcher)
  end

  it 'matches a valid value when using #=== so it can be composed' do
    expect(matcher).to be === valid_value
  end

  it 'does not match an invalid value when using #=== so it can be composed' do
    expect(matcher).not_to be === invalid_value
  end

  matcher :always_passes do
    match { true }
  end

  matcher :always_fails do
    match { false }
  end

  it 'supports compound expectations by chaining `and`' do
    expect(valid_value).to matcher.and always_passes
  end

  it 'supports compound expectations by chaining `or`' do
    expect(valid_value).to matcher.or always_fails
  end
end

Version data entries

1 entries across 1 versions & 1 rubygems

Version	Path
rspec-expectations-3.0.0.beta2	spec/support/shared_examples.rb