minitest_mock_test.rb

require "minitest/autorun"

class MinitestMockTest < Minitest::Test
  def test_method_called_more_times_than_expected
    mock = Minitest::Mock.new
    3.times { mock.expect :some_method, true }

    assert mock.some_method    # OK
    assert mock.some_method    # OK
    assert mock.some_method    # still OK
    assert mock.some_method    # MockExpectationError
  end
end

test output

$ ruby minitest_mock_test.rb 
Run options: --seed 25695

# Running:

E

Finished in 0.000932s, 1072.6138 runs/s, 3217.8414 assertions/s.

  1) Error:
MinitestMockTest#test_method_called_more_times_than_expected:
MockExpectationError: No more expects available for :some_method: []
    minitest_mock_test.rb:11:in `test_method_called_more_times_than_expected'

1 runs, 3 assertions, 0 failures, 1 errors, 0 skips