Add test minitest integration

[fix #92]

config/flay.yml

@@ -1,3 +1,3 @@
 ---
 threshold: 18
-total_score: 1177
+total_score: 1207

config/reek.yml

@@ -80,6 +80,7 @@ TooManyStatements:
  - Mutant::CLI#add_debug_options
  - Mutant::CLI#add_environment_options
  - Mutant::Isolation::Fork#self.call
+ - Mutant::Integration::Minitest#call
  - Mutant::Reporter::CLI::Printer::Config#run
  - Mutant::Reporter::CLI::Printer::EnvProgress#run
  - Mutant::Runner#run_driver
@@ -130,6 +131,7 @@ UtilityFunction:
  - Mutant::Integration::Null#call
  - Mutant::Integration::Rspec#parse_example
  - Mutant::Integration::Rspec#parse_expression # intentional, private
+ - Mutant::Integration::Minitest#test_case # intentional, private
  - Mutant::Meta::Example::Verification#format_mutation
  - Mutant::Reporter::CLI::Format::Progressive#new_buffer
  - Mutant::Reporter::CLI::Printer::StatusProgressive#object # False positive calls super

lib/mutant/integration/minitest.rb

@@ -0,0 +1,152 @@
+require 'minitest'
+
+# monkey patch for minitest
+module Minitest
+ # Prevent autorun from running tests when the VM closes
+ #
+ # Mutant needs control about the exit status of the VM and
+ # the moment of test execution
+ #
+ # @api private
+ #
+ # @return [nil]
+ def self.autorun
+ end
+
+end # Minitest
+
+module Mutant
+ class Integration
+ # Minitest integration
+ class Minitest < self
+ TEST_FILE_PATTERN = './test/**/{test_*,*_test}.rb'.freeze
+ IDENTIFICATION_FORMAT = 'minitest:%s#%s'.freeze
+
+ private_constant(*constants(false))
+
+ # Compose a runnable with test method
+ #
+ # This looks actually like a missing object on minitest implementation.
+ class TestCase
+ include Adamantium, Concord.new(:klass, :test_method)
+
+ # Identification string
+ #
+ # @return [String]
+ def identification
+ IDENTIFICATION_FORMAT % [klass, test_method]
+ end
+ memoize :identification
+
+ # Run test case
+ #
+ # @param [Object] reporter
+ #
+ # @return [Boolean]
+ def call(reporter)
+ ::Minitest::Runnable.run_one_method(klass, test_method, reporter)
+ reporter.passed?
+ end
+
+ # Cover expression syntaxes
+ #
+ # @return [Array<String>]
+ def expression_syntax
+ klass.cover_expression
+ end
+
+ end # TestCase
+
+ private_constant(*constants(false))
+
+ # Setup integration
+ #
+ # @return [self]
+ def setup
+ Pathname.glob(TEST_FILE_PATTERN)
+ .map(&:to_s)
+ .each(&method(:require))
+
+ self
+ end
+
+ # Call test integration
+ #
+ # @param [Array<Tests>] tests
+ #
+ # @return [Result::Test]
+ #
+ # rubocop:disable MethodLength
+ def call(tests)
+ test_cases = tests.map(&all_tests_index.method(:fetch)).to_set
+
+ output = StringIO.new
+ reporter = ::Minitest::SummaryReporter.new(output)
+ start = Time.now
+
+ passed = test_cases.all? { |test| test.call(reporter) }
+ output.rewind
+
+ Result::Test.new(
+ passed: passed,
+ tests: tests,
+ output: output.read,
+ runtime: Time.now - start
+ )
+ end
+
+ # All tests exposed by this integration
+ #
+ # @return [Array<Test>]
+ def all_tests
+ all_tests_index.keys
+ end
+ memoize :all_tests
+
+ private
+
+ # The index of all tests to runnable test cases
+ #
+ # @return [Hash<Test,TestCase>]
+ def all_tests_index
+ all_test_cases.each_with_object({}) do |test_case, index|
+ index[construct_test(test_case)] = test_case
+ end
+ end
+ memoize :all_tests_index
+
+ # Construct test from test case
+ #
+ # @param [TestCase]
+ #
+ # @return [Test]
+ def construct_test(test_case)
+ Test.new(
+ id: test_case.identification,
+ expression: config.expression_parser.(test_case.expression_syntax)
+ )
+ end
+
+ # All minitest test cases
+ #
+ # Intentional utility method.
+ #
+ # @return [Array<TestCase>]
+ def all_test_cases
+ ::Minitest::Runnable.runnables.flat_map(&method(:test_case))
+ end
+
+ # Turn a minitest runnable into its test cases
+ #
+ # Intentional utility method.
+ #
+ # @param [Object] runnable
+ #
+ # @return [Array<TestCase>]
+ def test_case(runnable)
+ runnable.runnable_methods.map(&TestCase.method(:new))
+ end
+
+ end # Minitest
+ end # Integration
+end # Mutant

mutant-minitest.gemspec

@@ -0,0 +1,22 @@
+# encoding: utf-8
+#
+require File.expand_path('../lib/mutant/version', __FILE__)
+
+Gem::Specification.new do |gem|
+ gem.name = 'mutant-minitest'
+ gem.version = Mutant::VERSION.dup
+ gem.authors = ['Markus Schirp']
+ gem.email = %w[[email protected]]
+ gem.description = 'Minitest integration for mutant'
+ gem.summary = gem.description
+ gem.homepage = 'https://github.com/mbj/mutant'
+ gem.license = 'MIT'
+
+ gem.require_paths = %w[lib]
+ gem.files = `git ls-files -- lib/mutant/integration/minitest.rb`.split("\n")
+ gem.test_files = `git ls-files -- spec/integration/mutant/minitest.rb`.split("\n")
+ gem.extra_rdoc_files = %w[TODO LICENSE]
+
+ gem.add_runtime_dependency('mutant', "~> #{gem.version}")
+ gem.add_runtime_dependency('minitest', '~> 5.5')
+end

spec/integration/mutant/minitest_spec.rb

@@ -0,0 +1,10 @@
+RSpec.describe 'minitest integration', mutant: false do
+
+ let(:base_cmd) { 'bundle exec mutant -I test -I lib --require test_app --use minitest' }
+
+ context 'Minitest 5.5.0' do
+ let(:gemfile) { 'Gemfile.minitest-stdlib' }
+
+ it_behaves_like 'framework integration'
+ end
+end

spec/shared/framework_integration_behavior.rb

@@ -16,10 +16,11 @@
  specify 'it allows to exclude mutations' do
  cli = <<-CMD.split("\n").join(' ')
  #{base_cmd}
+ --ignore-subject TestApp::Literal#uncovered_string
  TestApp::Literal#string
  TestApp::Literal#uncovered_string
- --ignore-subject TestApp::Literal#uncovered_string
  CMD
+
  expect(Kernel.system(cli)).to be(true)
  end
 

spec/unit/mutant/integration/isolation_spec.rb

@@ -0,0 +1,41 @@
+RSpec.describe Mutant::Isolation::Fork, mutant: false do
+ let(:object) { Mutant::Config::DEFAULT.isolation }
+
+ it 'does isolate side effects' do
+ initial = 1
+ object.call { initial = 2 }
+ expect(initial).to be(1)
+ end
+
+ it 'return block value' do
+ expect(object.call { :foo }).to be(:foo)
+ end
+
+ it 'wraps exceptions' do
+ expect { object.call { fail } }.to raise_error(
+ Mutant::Isolation::Error,
+ 'marshal data too short'
+ )
+ end
+
+ it 'wraps exceptions caused by crashing ruby' do
+ expect do
+ object.call do
+ fail RbBug.call
+ end
+ end.to raise_error(Mutant::Isolation::Error)
+ end
+
+ it 'redirects $stderr of children to /dev/null' do
+ begin
+ Tempfile.open('mutant-test') do |file|
+ $stderr = file
+ object.call { $stderr.puts('test') }
+ file.rewind
+ expect(file.read).to eql('')
+ end
+ ensure
+ $stderr = STDERR
+ end
+ end
+end

test_app/Gemfile.minitest-stdlib

@@ -0,0 +1,6 @@
+source 'https://rubygems.org'
+
+gem 'minitest', '~> 5.5'
+gem 'mutant', path: '../'
+gem 'mutant-minitest', path: '../'
+gem 'adamantium'

test_app/test/test_helper.rb

@@ -0,0 +1,19 @@
+$LOAD_PATH << File.join(File.dirname(__FILE__), '../lib')
+
+require 'test_app'
+require 'minitest/autorun'
+
+# require spec support files and shared behavior
+Dir[File.expand_path('../{support,shared}/**/*.rb', __FILE__)].sort.each do |file|
+ require file
+end
+
+class TestAppTest < Minitest::Test
+ def self.cover(expression)
+ @expression = expression
+ end
+
+ def self.cover_expression
+ @expression or fail "Cover expression for #{self} is not specified"
+ end
+end

test_app/test/unit/test_app/literal_test.rb

@@ -0,0 +1,19 @@
+require 'test_helper'
+
+class TestApp::LiteralTest < TestAppTest
+ cover 'TestApp::Literal*'
+
+ def test_command
+ object = ::TestApp::Literal.new
+ subject = object.command('x')
+
+ assert_equal object, subject
+ end
+
+ def test_string
+ object = ::TestApp::Literal.new
+ subject = object.string
+
+ assert_equal 'string', subject
+ end
+end