include_all_at_least_times.rb

Spec::Matchers.define :include_all_at_least_times do |expected_elements, times|
  match do |target_collection|
    @elements_seen = expected_elements.inject({ }) { |hash, element| hash[element] = 0; hash }

    target_collection.each do |element|
      @elements_seen[element] += 1 if @elements_seen.has_key?(element)
    end

    @elements_seen.values.all? { |count| count >= times.to_i }
  end
  
  failure_message_for_should do |target_collection|
    "Expected #{target_collection.inspect} to include #{expected_elements.inspect} at least #{times} got the following counts: #{@elements_seen.inspect}"
  end
end

include_all_once.rb

Spec::Matchers.define :include_all_once do |expected_elements|
  match do |target_collection|
    @missing    = []
    @non_unique = 0
    expected_elements.each do |expected_element|
      elements_in_target_collection = target_collection.select { |target| target == expected_element  }
      @missing << expected_element if elements_in_target_collection.empty?
      @non_unique += 1 if elements_in_target_collection.size > 1
    end
    @missing.empty? && @non_unique == 0
  end
  failure_message_for_should do |target_collection|
    if @missing.empty?
      "Expected #{target_collection.inspect} to include #{expected_elements.inspect} just once but saw #{@non_unique} non-unique elements."
    else
      "Expected #{target_collection.inspect} to include #{expected_elements.inspect} just once but was missing #{@missing.inspect}"
    end
  end
end

include_any.rb

Spec::Matchers.define :include_any do |expected_elements|
  match do |target_collection|
    @included = []
    expected_elements.each do |expected_element|
      @included << expected_element if target_collection.include?(expected_element)
    end
    !@included.empty?
  end
  failure_message_for_should_not do |target_collection|
    "Expected #{target_collection.inspect} not to include any of #{expected_elements.inspect} but saw #{@included.inspect}"
  end
end