class RSpec::Matchers::BuiltIn::Include

def actual_hash_has_key?(expected_key)
  # We check `key?` first for perf:
  # `key?` is O(1), but `any?` is O(N).
  has_exact_key =
    begin
      actual.key?(expected_key)
    rescue
      false
    end
  has_exact_key || actual.keys.any? { |key| values_match?(expected_key, key) }
end