include ::RSpec::Matchers
class A
include ::RSpec::Matchers
def test
expect('1'.to_i).to eq 1
end
def failed_test
expect('1'.to_i).to eq 2
end
end
A.new.test
# => true
A.new.failed_test
# RSpec::Expectations::ExpectationNotMetError:
# expected: 2
# got: 1