require 'rspec/any_of'
RSpec.configure do |config|
  # ...
  config.include RSpec::AnyOf
end

it 'sends greetings to chat' do
  expect(Chat)
    .to receive(:message)
    .with(all_of('Hello', 'My name is Phil')).twice
  # The only option normally is to be more verbose.
  # This is the most optimistic example, with more arguments it's getting noticeably worse.
  expect(Chat)
    .to  receive(:message).with('Hello')
    .and receive(:message).with('My name is Phil')
end
it 'greets' do
  expect(Greeter)
    .to receive(:greet)
    .with(any_of('hello', 'good bye'))
  # Or, normally:
  expect(Greeter)
    .to receive(:greet)
    .with(eq('hello').or(eq('good bye')))
end