module RSpec::Mocks::ArgumentMatchers

expect(object).to receive(:message).with(hash_including(:key, :key2 => val2))
expect(object).to receive(:message).with(hash_including(:key))
expect(object).to receive(:message).with(hash_including(:key => val))
@example

Ignores any additional keys.
Matches a hash that includes the specified key(s) or key/value pairs.

def hash_including(*args)
  HashIncludingMatcher.new(ArgumentMatchers.anythingize_lonely_keys(*args))
end