rails/activesupport/test/test_case_test.rb

require 'abstract_unit'

class AssertDifferenceTest < ActiveSupport::TestCase
  def setup
    @object = Class.new do
      attr_accessor :num
      def increment
        self.num += 1
      end

      def decrement
        self.num -= 1
      end
    end.new
    @object.num = 0
  end

  def test_assert_not
    assert_equal true, assert_not(nil)
    assert_equal true, assert_not(false)

    e = assert_raises(Minitest::Assertion) { assert_not true }
    assert_equal 'Expected true to be nil or false', e.message

    e = assert_raises(Minitest::Assertion) { assert_not true, 'custom' }
    assert_equal 'custom', e.message
  end

  def test_assert_no_difference_pass
    assert_no_difference '@object.num' do
      # ...
    end
  end

  def test_assert_no_difference_fail
    error = assert_raises(Minitest::Assertion) do
      assert_no_difference '@object.num' do
        @object.increment
      end
    end
    assert_equal "\"@object.num\" didn't change by 0.\nExpected: 0\n  Actual: 1", error.message
  end

  def test_assert_no_difference_with_message_fail
    error = assert_raises(Minitest::Assertion) do
      assert_no_difference '@object.num', 'Object Changed' do
        @object.increment
      end
    end
    assert_equal "Object Changed.\n\"@object.num\" didn't change by 0.\nExpected: 0\n  Actual: 1", error.message
  end

  def test_assert_difference
    assert_difference '@object.num', +1 do
      @object.increment
    end
  end

  def test_assert_difference_with_implicit_difference
    assert_difference '@object.num' do
      @object.increment
    end
  end

  def test_arbitrary_expression
    assert_difference '@object.num + 1', +2 do
      @object.increment
      @object.increment
    end
  end

  def test_negative_differences
    assert_difference '@object.num', -1 do
      @object.decrement
    end
  end

  def test_expression_is_evaluated_in_the_appropriate_scope
    silence_warnings do
      local_scope = local_scope = 'foo'
      assert_difference('local_scope; @object.num') { @object.increment }
    end
  end

  def test_array_of_expressions
    assert_difference [ '@object.num', '@object.num + 1' ], +1 do
      @object.increment
    end
  end

  def test_array_of_expressions_identify_failure
    assert_raises(Minitest::Assertion) do
      assert_difference ['@object.num', '1 + 1'] do
        @object.increment
      end
    end
  end

  def test_array_of_expressions_identify_failure_when_message_provided
    assert_raises(Minitest::Assertion) do
      assert_difference ['@object.num', '1 + 1'], 1, 'something went wrong' do
        @object.increment
      end
    end
  end
end

class AlsoDoingNothingTest < ActiveSupport::TestCase
end

# Setup and teardown callbacks.
class SetupAndTeardownTest < ActiveSupport::TestCase
  setup :reset_callback_record, :foo
  teardown :foo, :sentinel

  def test_inherited_setup_callbacks
    assert_equal [:reset_callback_record, :foo], self.class._setup_callbacks.map(&:raw_filter)
    assert_equal [:foo], @called_back
    assert_equal [:foo, :sentinel], self.class._teardown_callbacks.map(&:raw_filter)
  end

  def setup
  end

  def teardown
  end

  protected

    def reset_callback_record
      @called_back = []
    end

    def foo
      @called_back << :foo
    end

    def sentinel
      assert_equal [:foo], @called_back
    end
end

class SubclassSetupAndTeardownTest < SetupAndTeardownTest
  setup :bar
  teardown :bar

  def test_inherited_setup_callbacks
    assert_equal [:reset_callback_record, :foo, :bar], self.class._setup_callbacks.map(&:raw_filter)
    assert_equal [:foo, :bar], @called_back
    assert_equal [:foo, :sentinel, :bar], self.class._teardown_callbacks.map(&:raw_filter)
  end

  protected
    def bar
      @called_back << :bar
    end

    def sentinel
      assert_equal [:foo, :bar, :bar], @called_back
    end
end

class TestCaseTaggedLoggingTest < ActiveSupport::TestCase
  def before_setup
    require 'stringio'
    @out = StringIO.new
    self.tagged_logger = ActiveSupport::TaggedLogging.new(Logger.new(@out))
    super
  end

  def test_logs_tagged_with_current_test_case
    assert_match "#{self.class}: #{name}\n", @out.string
  end
end