minitest/{unit,spec,mock,benchmark}

home :: https://github.com/seattlerb/minitest
rdoc :: http://docs.seattlerb.org/minitest
vim :: https://github.com/sunaku/vim-ruby-minitest

DESCRIPTION:

minitest provides a complete suite of testing facilities supporting TDD, BDD, mocking, and benchmarking.

"I had a class with Jim Weirich on testing last week and we were
 allowed to choose our testing frameworks. Kirk Haines and I were
 paired up and we cracked open the code for a few test
 frameworks...

 I MUST say that minitest is *very* readable / understandable
 compared to the 'other two' options we looked at. Nicely done and
 thank you for helping us keep our mental sanity."

-- Wayne E. Seguin

minitest/unit is a small and incredibly fast unit testing framework. It provides a rich set of assertions to make your tests clean and readable.

minitest/spec is a functionally complete spec engine. It hooks onto minitest/unit and seamlessly bridges test assertions over to spec expectations.

minitest/benchmark is an awesome way to assert the performance of your algorithms in a repeatable manner. Now you can assert that your newb co-worker doesn't replace your linear algorithm with an exponential one!

minitest/mock by Steven Baker, is a beautifully tiny mock (and stub) object framework.

minitest/pride shows pride in testing and adds coloring to your test output. I guess it is an example of how to write IO pipes too. :P

minitest/unit is meant to have a clean implementation for language implementors that need a minimal set of methods to bootstrap a working test suite. For example, there is no magic involved for test-case discovery.

"Again, I can't praise enough the idea of a testing/specing
 framework that I can actually read in full in one sitting!"

-- Piotr Szotkowski

FEATURES/PROBLEMS:

• minitest/autorun - the easy and explicit way to run all your tests.
• minitest/unit - a very fast, simple, and clean test system.
• minitest/spec - a very fast, simple, and clean spec system.
• minitest/mock - a simple and clean mock/stub system.
• minitest/benchmark - an awesome way to assert your algorithm's performance.
• minitest/pride - show your pride in testing!
• Incredibly small and fast runner, but no bells and whistles.

RATIONALE:

See design_rationale.rb to see how specs and tests work in minitest.

SYNOPSIS:

Given that you'd like to test the following class:

  class Meme
    def i_can_has_cheezburger?
      "OHAI!"
    end

    def will_it_blend?
      "YES!"
    end
  end

Unit tests

  require 'minitest/autorun'

  class TestMeme < MiniTest::Unit::TestCase
    def setup
      @meme = Meme.new
    end

    def test_that_kitty_can_eat
      assert_equal "OHAI!", @meme.i_can_has_cheezburger?
    end

    def test_that_it_will_not_blend
      refute_match /^no/i, @meme.will_it_blend?
    end
  end

Specs

  require 'minitest/autorun'

  describe Meme do
    before do
      @meme = Meme.new
    end

    describe "when asked about cheeseburgers" do
      it "must respond positively" do
        @meme.i_can_has_cheezburger?.must_equal "OHAI!"
      end
    end

    describe "when asked about blending possibilities" do
      it "won't say no" do
        @meme.will_it_blend?.wont_match /^no/i
      end
    end
  end

For matchers support check out:

https://github.com/zenspider/minitest-matchers

Benchmarks

Add benchmarks to your regular unit tests. If the unit tests fail, the benchmarks won't run.

  # optionally run benchmarks, good for CI-only work!
  require 'minitest/benchmark' if ENV["BENCH"]

  class TestMeme < MiniTest::Unit::TestCase
    # Override self.bench_range or default range is [1, 10, 100, 1_000, 10_000]
    def bench_my_algorithm
      assert_performance_linear 0.9999 do |n| # n is a range value
        @obj.my_algorithm(n)
      end
    end
  end

Or add them to your specs. If you make benchmarks optional, you'll need to wrap your benchmarks in a conditional since the methods won't be defined.

  describe Meme do
    if ENV["BENCH"] then
      bench_performance_linear "my_algorithm", 0.9999 do |n|
        100.times do
          @obj.my_algorithm(n)
        end
      end
    end
  end

Running benchmarks:

TestBlah	100	1000	10000
bench_my_algorithm	0.006167	0.079279	0.786993
bench_other_algorithm	0.061679	0.792797	7.869932

Output is tab-delimited to make it easy to paste into a spreadsheet.

Mocks

  class MemeAsker
    def initialize(meme)
      @meme = meme
    end

    def ask(question)
      method = question.tr(" ","_") + "?"
      @meme.__send__(method)
    end
  end

  require 'minitest/autorun'

  describe MemeAsker do
    before do
      @meme = MiniTest::Mock.new
      @meme_asker = MemeAsker.new @meme
    end

    describe "#ask" do
      describe "when passed an unpunctuated question" do
        it "should invoke the appropriate predicate method on the meme" do
          @meme.expect :will_it_blend?, :return_value
          @meme_asker.ask "will it blend"
          @meme.verify
        end
      end
    end
  end

Stubs

  def test_stale_eh
    obj_under_test = Something.new

    refute obj_under_test.stale?

    Time.stub :now, Time.at(0) do   # stub goes away once the block is done
      assert obj_under_test.stale?
    end
  end

Customizable Test Runner Types:

MiniTest::Unit.runner=(runner) provides an easy way of creating custom test runners for specialized needs. Justin Weiss provides the following real-world example to create an alternative to regular fixture loading:

  class MiniTestWithHooks::Unit < MiniTest::Unit
    def before_suites
    end

    def after_suites
    end

    def _run_suites(suites, type)
      begin
        before_suites
        super(suites, type)
      ensure
        after_suites
      end
    end

    def _run_suite(suite, type)
      begin
        suite.before_suite
        super(suite, type)
      ensure
        suite.after_suite
      end
    end
  end

  module MiniTestWithTransactions
    class Unit < MiniTestWithHooks::Unit
      include TestSetupHelper

      def before_suites
        super
        setup_nested_transactions
        # load any data we want available for all tests
      end

      def after_suites
        teardown_nested_transactions
        super
      end
    end
  end

  MiniTest::Unit.runner = MiniTestWithTransactions::Unit.new

Known Extensions:

• minitest-capistrano :: Assertions and expectations for testing Capistrano recipes
• minitest-capybara :: Capybara matchers support for minitest unit and spec
• minitest-chef-handler :: Run Minitest suites as Chef report handlers
• minitest-ci :: CI reporter plugin for MiniTest.
• minitest-colorize :: Colorize MiniTest output and show failing tests instantly.
• minitest-context :: Defines contexts for code reuse in MiniTest specs that share common expectations.
• minitest-debugger :: Wraps assert so failed assertions drop into the ruby debugger.
• minitest-display :: Patches MiniTest to allow for an easily configurable output.
• minitest-emoji :: Print out emoji for your test passes, fails, and skips.
• minitest-excludes :: Clean API for excluding certain tests you don't want to run under certain conditions.
• minitest-firemock :: Makes your MiniTest mocks more resilient.
• minitest-growl :: Test notifier for minitest via growl.
• minitest-instrument :: Instrument ActiveSupport::Notifications when test method is executed
• minitest-instrument-db :: Store information about speed of test execution provided by minitest-instrument in database
• minitest-libnotify :: Test notifier for minitest via libnotify.
• minitest-macruby :: Provides extensions to minitest for macruby UI testing.
• minitest-matchers :: Adds support for RSpec-style matchers to minitest.
• minitest-metadata :: Annotate tests with metadata (key-value).
• minitest-mongoid :: Mongoid assertion matchers for MiniTest
• minitest-must_not :: Provides must_not as an alias for wont in MiniTest
• minitest-predicates :: Adds support for .predicate? methods
• minitest-pry :: A minitest plugin to drop into pry on assertion failure.
• minitest-rails :: MiniTest integration for Rails 3.1.
• minitest-reporters :: Create customizable MiniTest output formats
• minitest-rg :: redgreen minitest
• minitest-spec-magic :: Minitest::Spec extensions for Rails and beyond
• minitest-tags :: add tags for minitest
• minitest-wscolor :: Yet another test colorizer.
• minitest_owrapper :: Get tests results as a TestResult object.
• minitest_should :: Shoulda style syntax for minitest test::unit.
• minitest_tu_shim :: minitest_tu_shim bridges between test/unit and minitest.
• mongoid-minitest :: MiniTest matchers for Mongoid.

REQUIREMENTS:

• Ruby 1.8, maybe even 1.6 or lower. No magic is involved.

INSTALL:

sudo gem install minitest

On 1.9, you already have it. To get newer candy you can still install the gem, but you'll need to activate the gem explicitly to use it:

require 'rubygems' gem 'minitest' # ensures you're using the gem, and not the built in MT require 'minitest/autorun'

... usual testing stuffs ...

LICENSE:

(The MIT License)

Copyright (c) Ryan Davis, seattle.rb

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the 'Software'), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED 'AS IS', WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.