what_to_test

should_you_test.rb

#example_code
def search(query, page_number)
  third_party_search_library.search("*{query}*").from(page_number * page_size).size(page_size).matched_results
end

#example_unit_test
it "should search for partial match and return paged result" do
  third_party_search_library.should_receive(:search).with('*new york*').and_return(cities)
  cities.should_receive(:from).with(40).and_return(cities)
  cities.should_receive(:size).with(20).and_return(cities)

  City.search('new york', 2).should == cities
end