require "helper" class TestActiveSupportAssertions < ActiveSupport::TestCase def test_assert_difference counter = 0 assert_difference "counter" do counter += 1 end assert_difference "counter", +1 do counter += 1 end assert_difference "counter", +3 do 3.times { counter += 1 } end end def test_refute_difference counter = 0 refute_difference "counter" do counter = 0 end end def test_assert_no_difference counter = 0 assert_no_difference "counter" do counter = 0 end end end