undefined method `assert_no_difference’ and `assert_difference’

I’ve been upgrading some old code and noticed that my unit tests started spitting out a lot of errors like this:

undefined method `assert_no_difference'
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and


undefined method `assert_difference'
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It turns out that I needed to change my base classes from <strong>Test::Unit::TestCase</strong> to <strong>ActiveSupport::TestCase</strong>:


class UserTest < Test::Unit::TestCase
  # stuff
end
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<p>changes to:</p>


class UserTest < ActiveSupport::TestCase
  # stuff
end
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