Move dependency "devtools" to the repo

Gemfile

@@ -4,4 +4,6 @@ source 'https://rubygems.org'
 
 gemspec name: 'mutant'
 
+gem 'devtools', path: 'devtools'
+
 eval_gemfile File.expand_path('Gemfile.shared', __dir__)

Gemfile.lock

@@ -20,6 +20,29 @@ PATH
       mutant (~> 0.8.24)
       rspec-core (>= 3.4.0, < 4.0.0)
 
+PATH
+  remote: devtools
+  specs:
+    devtools (0.1.22)
+      abstract_type (~> 0.0.7)
+      adamantium (~> 0.2.0)
+      anima (~> 0.3.0)
+      concord (~> 0.1.5)
+      flay (~> 2.12.0)
+      flog (~> 4.6.2)
+      mutant (~> 0.8.19)
+      mutant-rspec (~> 0.8.19)
+      procto (~> 0.0.3)
+      rake (~> 12.3.0)
+      reek (~> 5.2.0)
+      rspec (~> 3.8.0)
+      rspec-core (~> 3.8.0)
+      rspec-its (~> 1.2.0)
+      rubocop (~> 0.60.0)
+      simplecov (~> 0.16.1)
+      yard (~> 0.9.16)
+      yardstick (~> 0.9.9)
+
 GEM
   remote: https://rubygems.org/
   specs:
@@ -45,41 +68,22 @@ GEM
       equalizer (~> 0.0.9)
     descendants_tracker (0.0.4)
       thread_safe (~> 0.3, >= 0.3.1)
-    devtools (0.1.22)
-      abstract_type (~> 0.0.7)
-      adamantium (~> 0.2.0)
-      anima (~> 0.3.0)
-      concord (~> 0.1.5)
-      flay (~> 2.12.0)
-      flog (~> 4.6.2)
-      mutant (~> 0.8.19)
-      mutant-rspec (~> 0.8.19)
-      procto (~> 0.0.3)
-      rake (~> 12.3.0)
-      reek (~> 5.2.0)
-      rspec (~> 3.8.0)
-      rspec-core (~> 3.8.0)
-      rspec-its (~> 1.2.0)
-      rubocop (~> 0.60.0)
-      simplecov (~> 0.16.1)
-      yard (~> 0.9.16)
-      yardstick (~> 0.9.9)
     diff-lcs (1.3)
-    docile (1.3.1)
+    docile (1.3.5)
     equalizer (0.0.11)
     erubis (2.7.0)
-    flay (2.12.0)
+    flay (2.12.1)
       erubis (~> 2.7.0)
       path_expander (~> 1.0)
       ruby_parser (~> 3.0)
       sexp_processor (~> 4.0)
-    flog (4.6.2)
+    flog (4.6.4)
       path_expander (~> 1.0)
       ruby_parser (~> 3.1, > 3.1.0)
       sexp_processor (~> 4.8)
     ice_nine (0.11.2)
-    jaro_winkler (1.5.1)
-    json (2.1.0)
+    jaro_winkler (1.5.4)
+    json (2.5.1)
     kwalify (0.7.2)
     memoizable (0.4.2)
       thread_safe (~> 0.3, >= 0.3.1)
@@ -95,11 +99,11 @@ GEM
     parallel (1.12.1)
     parser (2.5.3.0)
       ast (~> 2.4.0)
-    path_expander (1.0.3)
-    powerpack (0.1.2)
+    path_expander (1.1.0)
+    powerpack (0.1.3)
     procto (0.0.3)
     rainbow (3.0.0)
-    rake (12.3.1)
+    rake (12.3.3)
     reek (5.2.0)
       codeclimate-engine-rb (~> 0.4.0)
       kwalify (~> 0.7.0)
@@ -110,18 +114,18 @@ GEM
       rspec-core (~> 3.8.0)
       rspec-expectations (~> 3.8.0)
       rspec-mocks (~> 3.8.0)
-    rspec-core (3.8.0)
+    rspec-core (3.8.2)
       rspec-support (~> 3.8.0)
-    rspec-expectations (3.8.2)
+    rspec-expectations (3.8.6)
       diff-lcs (>= 1.2.0, < 2.0)
       rspec-support (~> 3.8.0)
     rspec-its (1.2.0)
       rspec-core (>= 3.0.0)
       rspec-expectations (>= 3.0.0)
-    rspec-mocks (3.8.0)
+    rspec-mocks (3.8.2)
       diff-lcs (>= 1.2.0, < 2.0)
       rspec-support (~> 3.8.0)
-    rspec-support (3.8.0)
+    rspec-support (3.8.3)
     rubocop (0.60.0)
       jaro_winkler (~> 1.5.1)
       parallel (~> 1.10)
@@ -130,17 +134,17 @@ GEM
       rainbow (>= 2.2.2, < 4.0)
       ruby-progressbar (~> 1.7)
       unicode-display_width (~> 1.4.0)
-    ruby-progressbar (1.10.0)
-    ruby_parser (3.11.0)
+    ruby-progressbar (1.11.0)
+    ruby_parser (3.15.1)
       sexp_processor (~> 4.9)
-    sexp_processor (4.11.0)
+    sexp_processor (4.15.2)
     simplecov (0.16.1)
       docile (~> 1.1)
       json (>= 1.8, < 3)
       simplecov-html (~> 0.10.0)
     simplecov-html (0.10.2)
     thread_safe (0.3.6)
-    unicode-display_width (1.4.0)
+    unicode-display_width (1.4.1)
     unparser (0.4.2)
       abstract_type (~> 0.0.7)
       adamantium (~> 0.2.0)
@@ -154,7 +158,7 @@ GEM
       coercible (~> 1.0)
       descendants_tracker (~> 0.0, >= 0.0.3)
       equalizer (~> 0.0, >= 0.0.9)
-    yard (0.9.16)
+    yard (0.9.26)
     yardstick (0.9.9)
       yard (~> 0.8, >= 0.8.7.2)
 
@@ -162,9 +166,9 @@ PLATFORMS
   ruby
 
 DEPENDENCIES
-  devtools (~> 0.1.22)
+  devtools!
   mutant!
   parallel (~> 1.3)
 
 BUNDLED WITH
-   1.17.1
+   1.17.3

devtools/.circleci/config.yml

@@ -0,0 +1,41 @@
+defaults: &defaults
+  working_directory: ~/mutant
+  docker:
+    - image: circleci/ruby:2.5.3
+version: 2
+jobs:
+  unit_specs:
+    <<: *defaults
+    steps:
+      - checkout
+      - run: bundle install
+      - run: bundle exec rspec spec/unit
+  integration_specs:
+    <<: *defaults
+    steps:
+      - checkout
+      - run: bundle install
+      - run: bundle exec rspec spec/integration
+  metrics:
+    <<: *defaults
+    steps:
+      - checkout
+      - run: bundle install
+      - run: bundle exec rake metrics:rubocop
+      - run: bundle exec rake metrics:reek
+      - run: bundle exec rake metrics:flay
+      - run: bundle exec rake metrics:flog
+  mutant:
+    <<: *defaults
+    steps:
+      - checkout
+      - run: bundle install
+      - run: bundle exec rake metrics:mutant
+workflows:
+  version: 2
+  test:
+    jobs:
+      - unit_specs
+      - integration_specs
+      - metrics
+      - mutant

devtools/.gitignore

@@ -0,0 +1,37 @@
+## MAC OS
+.DS_Store
+
+## TEXTMATE
+*.tmproj
+tmtags
+
+## EMACS
+*~
+\#*
+.\#*
+
+## VIM
+*.sw[op]
+
+## Rubinius
+*.rbc
+.rbx
+
+## PROJECT::GENERAL
+*.gem
+coverage
+profiling
+turbulence
+rdoc
+pkg
+tmp
+doc
+log
+.yardoc
+measurements
+
+## BUNDLER
+.bundle
+Gemfile.lock
+
+## PROJECT::SPECIFIC

devtools/.rspec

@@ -0,0 +1,6 @@
+--color
+--format progress
+--profile
+--warnings
+--order random
+--require spec_helper

devtools/.rubocop.yml

@@ -0,0 +1,4 @@
+AllCops:
+  DisplayCopNames: true
+  Include:
+    - 'Gemfile'

devtools/Gemfile

@@ -0,0 +1,3 @@
+source 'https://rubygems.org'
+
+gemspec

devtools/LICENSE

@@ -0,0 +1,20 @@
+Copyright (c) 2014 Markus Schirp
+
+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.

devtools/README.md

@@ -0,0 +1,47 @@
+# devtools
+
+[![Build Status](https://img.shields.io/circleci/project/mbj/devtools.svg)](https://circleci.com/gh/mbj/devtools/tree/master)
+[![Dependency Status](https://gemnasium.com/mbj/devtools.png)](https://gemnasium.com/mbj/devtools)
+[![Code Climate](https://codeclimate.com/github/datamapper/devtools.png)](https://codeclimate.com/github/datamapper/devtools)
+<!-- [![Code Climate](https://codeclimate.com/github/mbj/devtools.png)](https://codeclimate.com/github/mbj/devtools) -->
+
+Metagem to assist development.
+Used to centralize metric setup and development gem dependencies.
+
+## Installation
+
+Add the gem to your Gemfile's development section.
+
+```ruby
+group :development, :test do
+  gem 'devtools', '~> 0.1.x'
+end
+```
+
+## RSpec support
+
+If you're using RSpec and want to have access to our common setup just adjust
+`spec/spec_helper.rb` to include
+
+```ruby
+require 'devtools/spec_helper'
+```
+
+## Credits
+
+The whole [ROM](https://github.com/rom-rb) team that created and maintained all
+these tasks before they were centralized here.
+
+## Contributing
+
+* Fork the project.
+* Make your feature addition or bug fix.
+* Add tests for it. This is important so I don't break it in a
+  future version unintentionally.
+* Commit, do not mess with Rakefile or version
+  (if you want to have your own version, that is fine but bump version in a commit by itself I can ignore when I pull)
+* Send me a pull request. Bonus points for topic branches.
+
+## License
+
+See `LICENSE` file.

devtools/Rakefile

@@ -0,0 +1,5 @@
+require 'devtools'
+
+ENV['DEVTOOLS_SELF'] = '1'
+
+Devtools.init_rake_tasks

devtools/config/devtools.yml

@@ -0,0 +1,2 @@
+---
+unit_test_timeout: 0.2

devtools/config/flay.yml

@@ -0,0 +1,3 @@
+---
+threshold: 8
+total_score: 122

devtools/config/flog.yml

@@ -0,0 +1,2 @@
+---
+threshold: 13.5

devtools/config/mutant.yml

@@ -0,0 +1,4 @@
+name: devtools
+namespace: Devtools
+ignore_subjects:
+- "Devtools::Flay::Scale#flay"

devtools/config/reek.yml

@@ -0,0 +1,106 @@
+---
+detectors:
+  Attribute:
+    enabled: false
+    exclude: []
+  BooleanParameter:
+    enabled: true
+    exclude: []
+  ClassVariable:
+    enabled: true
+    exclude: []
+  ControlParameter:
+    enabled: true
+    exclude: []
+  DataClump:
+    enabled: true
+    exclude: []
+    max_copies: 0
+    min_clump_size: 2
+  DuplicateMethodCall:
+    enabled: true
+    exclude: []
+    max_calls: 1
+    allow_calls: []
+  FeatureEnvy:
+    enabled: true
+    exclude: []
+  IrresponsibleModule:
+    enabled: true
+    exclude: []
+  LongParameterList:
+    enabled: true
+    exclude:
+    - Devtools::Config#self.attribute
+    max_params: 2
+    overrides: {}
+  LongYieldList:
+    enabled: true
+    exclude: []
+    max_params: 0
+  NestedIterators:
+    enabled: true
+    exclude: []
+    max_allowed_nesting: 1
+    ignore_iterators: []
+  NilCheck:
+    enabled: true
+    exclude: []
+  RepeatedConditional:
+    enabled: true
+    exclude: []
+    max_ifs: 1
+  TooManyConstants:
+    enabled: true
+    exclude:
+    - Devtools
+  TooManyInstanceVariables:
+    enabled: true
+    exclude: []
+    max_instance_variables: 2
+  TooManyMethods:
+    enabled: true
+    exclude: []
+    max_methods: 15
+  TooManyStatements:
+    enabled: true
+    exclude: []
+    max_statements: 5
+  UncommunicativeMethodName:
+    enabled: true
+    exclude: []
+    reject:
+    - '/^[a-z]$/'
+    - '/[0-9]$/'
+    - '/[A-Z]/'
+    accept: []
+  UncommunicativeModuleName:
+    enabled: true
+    exclude: []
+    reject:
+    - '/^.$/'
+    - '/[0-9]$/'
+    accept: []
+  UncommunicativeParameterName:
+    enabled: true
+    exclude: []
+    reject:
+    - '/^.$/'
+    - '/[0-9]$/'
+    - '/[A-Z]/'
+    accept: []
+  UncommunicativeVariableName:
+    enabled: true
+    exclude: []
+    reject:
+    - '/^.$/'
+    - '/[0-9]$/'
+    - '/[A-Z]/'
+    accept: []
+  UnusedParameters:
+    enabled: true
+    exclude: []
+  UtilityFunction:
+    enabled: true
+    exclude:
+    - Devtools::Project::Initializer::Rspec#require_files # intentional for deduplication

devtools/config/rubocop.yml

@@ -0,0 +1,151 @@
+inherit_from: ../.rubocop.yml
+
+AllCops:
+  TargetRubyVersion: 2.5.0
+
+Metrics/BlockLength:
+  Exclude:
+  # Ignore RSpec DSL
+    - spec/**/*
+  # Ignore gemspec DSL
+    - '*.gemspec'
+
+Naming/FileName:
+  Exclude:
+    - Rakefile
+
+# Avoid parameter lists longer than five parameters.
+ParameterLists:
+  Max: 3
+  CountKeywordArgs: true
+
+# Avoid more than `Max` levels of nesting.
+BlockNesting:
+  Max: 3
+
+# Align with the style guide.
+CollectionMethods:
+  PreferredMethods:
+    collect:  'map'
+    inject:   'reduce'
+    find:     'detect'
+    find_all: 'select'
+
+# Do not force public/protected/private keyword to be indented at the same
+# level as the def keyword. My personal preference is to outdent these keywords
+# because I think when scanning code it makes it easier to identify the
+# sections of code and visually separate them. When the keyword is at the same
+# level I think it sort of blends in with the def keywords and makes it harder
+# to scan the code and see where the sections are.
+AccessModifierIndentation:
+  Enabled: false
+
+# Limit line length
+LineLength:
+  Max: 106
+
+# Disable documentation checking until a class needs to be documented once
+Documentation:
+  Enabled: false
+
+# Do not always use &&/|| instead of and/or.
+AndOr:
+  Enabled: false
+
+# Do not favor modifier if/unless usage when you have a single-line body
+IfUnlessModifier:
+  Enabled: false
+
+# Allow case equality operator (in limited use within the specs)
+CaseEquality:
+  Enabled: false
+
+# Constants do not always have to use SCREAMING_SNAKE_CASE
+ConstantName:
+  Enabled: false
+
+# Not all trivial readers/writers can be defined with attr_* methods
+TrivialAccessors:
+  Enabled: false
+
+# Allow empty lines around class body
+EmptyLinesAroundClassBody:
+  Enabled: false
+
+# Allow empty lines around module body
+EmptyLinesAroundModuleBody:
+  Enabled: false
+
+# Allow empty lines around block body
+EmptyLinesAroundBlockBody:
+  Enabled: false
+
+# Allow multiple line operations to not require indentation
+MultilineOperationIndentation:
+  Enabled: false
+
+# Prefer String#% over Kernel#sprintf
+FormatString:
+  Enabled: false
+
+# Use square brackets for literal Array objects
+PercentLiteralDelimiters:
+  PreferredDelimiters:
+    '%':  '{}'
+    '%i': '[]'
+    '%q': ()
+    '%Q': ()
+    '%r': '{}'
+    '%s': ()
+    '%w': '[]'
+    '%W': '[]'
+    '%x': ()
+
+# Align if/else blocks with the variable assignment
+EndAlignment:
+  EnforcedStyleAlignWith: variable
+
+# Do not always align parameters when it is easier to read
+AlignParameters:
+  Exclude:
+    - spec/**/*_spec.rb
+
+# Prefer #kind_of? over #is_a?
+ClassCheck:
+  EnforcedStyle: kind_of?
+
+# Do not prefer double quotes to be used when %q or %Q is more appropriate
+UnneededPercentQ:
+  Enabled: false
+
+# Allow a maximum ABC score
+Metrics/AbcSize:
+  Max: 20.1
+
+# Do not prefer lambda.call(...) over lambda.(...)
+LambdaCall:
+  Enabled: false
+
+# Allow additional spaces
+ExtraSpacing:
+  Enabled: false
+
+# All objects can still be mutated if their eigenclass is patched
+RedundantFreeze:
+  Enabled: false
+
+# Prefer using `fail` when raising and `raise` when reraising
+SignalException:
+  EnforcedStyle: semantic
+
+Style/FrozenStringLiteralComment:
+  Enabled: false
+
+Style/CommentedKeyword:
+  Enabled: false
+
+Style/MixinGrouping:
+  Enabled: false
+
+Layout/MultilineMethodCallIndentation:
+  EnforcedStyle: indented

devtools/config/yardstick.yml

@@ -0,0 +1,2 @@
+---
+threshold: 100

devtools/devtools.gemspec

@@ -0,0 +1,36 @@
+Gem::Specification.new do |gem|
+  gem.name        = 'devtools'
+  gem.version     = '0.1.22'
+  gem.authors     = ['Markus Schirp']
+  gem.email       = ['mbj@schirp-dso.com']
+  gem.description = 'A metagem wrapping development tools'
+  gem.summary     = gem.description
+  gem.homepage    = 'https://github.com/rom-rb/devtools'
+  gem.license     = 'MIT'
+
+  gem.require_paths         = %w[lib]
+  gem.files                 = `git ls-files`.split("\n")
+  gem.executables           = %w[]
+  gem.test_files            = `git ls-files -- spec`.split("\n")
+  gem.extra_rdoc_files      = %w[README.md]
+  gem.required_ruby_version = '>= 2.5'
+
+  gem.add_runtime_dependency 'abstract_type', '~> 0.0.7'
+  gem.add_runtime_dependency 'adamantium',    '~> 0.2.0'
+  gem.add_runtime_dependency 'anima',         '~> 0.3.0'
+  gem.add_runtime_dependency 'concord',       '~> 0.1.5'
+  gem.add_runtime_dependency 'flay',          '~> 2.12.0'
+  gem.add_runtime_dependency 'flog',          '~> 4.6.2'
+  gem.add_runtime_dependency 'mutant',        '~> 0.8.19'
+  gem.add_runtime_dependency 'mutant-rspec',  '~> 0.8.19'
+  gem.add_runtime_dependency 'procto',        '~> 0.0.3'
+  gem.add_runtime_dependency 'rake',          '~> 12.3.0'
+  gem.add_runtime_dependency 'reek',          '~> 5.2.0'
+  gem.add_runtime_dependency 'rspec',         '~> 3.8.0'
+  gem.add_runtime_dependency 'rspec-core',    '~> 3.8.0'
+  gem.add_runtime_dependency 'rspec-its',     '~> 1.2.0'
+  gem.add_runtime_dependency 'rubocop',       '~> 0.60.0'
+  gem.add_runtime_dependency 'simplecov',     '~> 0.16.1'
+  gem.add_runtime_dependency 'yard',          '~> 0.9.16'
+  gem.add_runtime_dependency 'yardstick',     '~> 0.9.9'
+end

devtools/lib/devtools.rb

@@ -0,0 +1,96 @@
+# frozen_string_literal: true
+
+# Stdlib infrastructure
+require 'pathname'
+require 'rake'
+require 'timeout'
+require 'yaml'
+require 'fileutils'
+
+# Non stdlib infrastructure
+require 'abstract_type'
+require 'procto'
+require 'anima'
+require 'concord'
+require 'adamantium'
+
+# Wrapped tools
+require 'flay'
+require 'rspec'
+require 'rspec/its'
+require 'simplecov'
+
+# Main devtools namespace population
+module Devtools
+  ROOT                    = Pathname.new(__FILE__).parent.parent.freeze
+  PROJECT_ROOT            = Pathname.pwd.freeze
+  SHARED_PATH             = ROOT.join('shared').freeze
+  SHARED_SPEC_PATH        = SHARED_PATH.join('spec').freeze
+  DEFAULT_CONFIG_PATH     = ROOT.join('default/config').freeze
+  RAKE_FILES_GLOB         = ROOT.join('tasks/**/*.rake').to_s.freeze
+  LIB_DIRECTORY_NAME      = 'lib'
+  SPEC_DIRECTORY_NAME     = 'spec'
+  RAKE_FILE_NAME          = 'Rakefile'
+  SHARED_SPEC_PATTERN     = '{shared,support}/**/*.rb'
+  UNIT_TEST_PATH_REGEXP   = %r{\bspec/unit/}
+  DEFAULT_CONFIG_DIR_NAME = 'config'
+
+  private_constant(*constants(false))
+
+  # React to metric violation
+  #
+  # @param [String] msg
+  #
+  # @return [undefined]
+  #
+  # @api private
+  def self.notify_metric_violation(msg)
+    abort(msg)
+  end
+
+  # Initialize project and load tasks
+  #
+  # Should *only* be called from your $application_root/Rakefile
+  #
+  # @return [self]
+  #
+  # @api public
+  def self.init_rake_tasks
+    Project::Initializer::Rake.call
+    self
+  end
+
+  # Return devtools root path
+  #
+  # @return [Pathname]
+  #
+  # @api private
+  def self.root
+    ROOT
+  end
+
+  # Return project
+  #
+  # @return [Project]
+  #
+  # @api private
+  def self.project
+    PROJECT
+  end
+
+end # module Devtools
+
+# Devtools implementation
+require 'devtools/config'
+require 'devtools/project'
+require 'devtools/project/initializer'
+require 'devtools/project/initializer/rake'
+require 'devtools/project/initializer/rspec'
+require 'devtools/flay'
+require 'devtools/rake/flay'
+
+# Devtools self initialization
+module Devtools
+  # The project devtools is active for
+  PROJECT = Project.new(PROJECT_ROOT)
+end

devtools/lib/devtools/config.rb

@@ -0,0 +1,180 @@
+# frozen_string_literal: true
+
+module Devtools
+  # Abstract base class of tool configuration
+  class Config
+    include Adamantium::Flat, AbstractType, Concord.new(:config_dir)
+
+    # Represent no configuration
+    DEFAULT_CONFIG = {}.freeze
+
+    # Simple named type check representation
+    class TypeCheck
+      # Type check against expected class
+      include Concord.new(:name, :allowed_classes)
+
+      ERROR_FORMAT = '%<name>s: Got instance of %<got>s expected %<allowed>s'
+      CLASS_DELIM  = ','
+
+      # Check value for instance of expected class
+      #
+      # @param [Object] value
+      #
+      # @return [Object]
+      def call(value)
+        klass = value.class
+        format_values = {
+          name: name,
+          got: klass,
+          allowed: allowed_classes.join(CLASS_DELIM)
+        }
+
+        unless allowed_classes.any?(&klass.method(:equal?))
+          fail TypeError, format(ERROR_FORMAT, format_values)
+        end
+
+        value
+      end
+    end # TypeCheck
+
+    private_constant(*constants(false))
+
+    # Error raised on type errors
+    TypeError = Class.new(RuntimeError)
+
+    # Declare an attribute
+    #
+    # @param [Symbol] name
+    # @param [Array<Class>] classes
+    #
+    # @api private
+    #
+    # @return [self]
+    #
+    def self.attribute(name, classes, **options)
+      default    = [options.fetch(:default)] if options.key?(:default)
+      type_check = TypeCheck.new(name, classes)
+      key        = name.to_s
+
+      define_method(name) do
+        type_check.call(raw.fetch(key, *default))
+      end
+    end
+    private_class_method :attribute
+
+    # Return config path
+    #
+    # @return [String]
+    #
+    # @api private
+    #
+    def config_file
+      config_dir.join(self.class::FILE)
+    end
+    memoize :config_file
+
+  private
+
+    # Return raw data
+    #
+    # @return [Hash]
+    #
+    # @api private
+    #
+    def raw
+      yaml_config || DEFAULT_CONFIG
+    end
+    memoize :raw
+
+    # Return the raw config data from a yaml file
+    #
+    # @return [Hash]
+    #   returned if the yaml file is found
+    # @return [nil]
+    #   returned if the yaml file is not found
+    #
+    # @api private
+    #
+    def yaml_config
+      IceNine.deep_freeze(YAML.load_file(config_file)) if config_file.file?
+    end
+
+    # Rubocop configuration
+    class Rubocop < self
+      FILE = 'rubocop.yml'
+    end # Rubocop
+
+    # Reek configuration
+    class Reek < self
+      FILE = 'reek.yml'
+    end # Reek
+
+    # Flay configuration
+    #
+    class Flay < self
+      FILE             = 'flay.yml'
+      DEFAULT_LIB_DIRS = %w[lib].freeze
+      DEFAULT_EXCLUDES = %w[].freeze
+
+      attribute :total_score, [0.class]
+      attribute :threshold,   [0.class]
+      attribute :lib_dirs,    [Array], default: DEFAULT_LIB_DIRS
+      attribute :excludes,    [Array], default: DEFAULT_EXCLUDES
+    end # Flay
+
+    # Yardstick configuration
+    class Yardstick < self
+      FILE    = 'yardstick.yml'
+      OPTIONS = %w[
+        threshold
+        rules
+        verbose
+        path
+        require_exact_threshold
+      ].freeze
+
+      # Options hash that Yardstick understands
+      #
+      # @return [Hash]
+      #
+      # @api private
+      def options
+        OPTIONS.each_with_object({}) do |name, hash|
+          hash[name] = raw.fetch(name, nil)
+        end
+      end
+    end # Yardstick
+
+    # Flog configuration
+    class Flog < self
+      FILE             = 'flog.yml'
+      DEFAULT_LIB_DIRS = %w[lib].freeze
+
+      attribute :total_score, [Float]
+      attribute :threshold,   [Float]
+      attribute :lib_dirs,    [Array], default: DEFAULT_LIB_DIRS
+    end # Flog
+
+    # Mutant configuration
+    class Mutant < self
+      FILE             = 'mutant.yml'
+      DEFAULT_NAME     = ''
+      DEFAULT_STRATEGY = 'rspec'
+
+      attribute :name,            [String],                default: DEFAULT_NAME
+      attribute :strategy,        [String],                default: DEFAULT_STRATEGY
+      attribute :zombify,         [TrueClass, FalseClass], default: false
+      attribute :since,           [String, NilClass],      default: nil
+      attribute :ignore_subjects, [Array],                 default: []
+      attribute :namespace,       [String]
+    end # Mutant
+
+    # Devtools configuration
+    class Devtools < self
+      FILE                      = 'devtools.yml'
+      DEFAULT_UNIT_TEST_TIMEOUT = 0.1  # 100ms
+
+      attribute :unit_test_timeout, [Float], default: DEFAULT_UNIT_TEST_TIMEOUT
+    end # Devtools
+  end # Config
+end # Devtools

devtools/lib/devtools/flay.rb

@@ -0,0 +1,98 @@
+# frozen_string_literal: true
+
+module Devtools
+  module Flay
+    # Measure flay mass relative to size of duplicated sexps
+    class Scale
+      include Adamantium
+      include Anima.new(:minimum_mass, :files)
+      include Procto.call(:measure)
+
+      # Measure duplication mass
+      #
+      # @return [Array<Rational>]
+      #
+      # @api private
+      def measure
+        flay.masses.map do |hash, mass|
+          Rational(mass, flay.hashes.fetch(hash).size)
+        end
+      end
+
+      # Report flay output
+      #
+      # @return [undefined]
+      #
+      # @api private
+      def flay_report
+        flay.report
+      end
+
+    private
+
+      # Memoized flay instance
+      #
+      # @return [Flay]
+      #
+      # @api private
+      def flay
+        ::Flay.new(mass: minimum_mass).tap do |flay|
+          flay.process(*files)
+          flay.analyze
+        end
+      end
+      memoize :flay, freezer: :noop
+    end
+
+    # Expand include and exclude file settings for flay
+    class FileList
+      include Procto.call, Concord.new(:includes, :excludes)
+
+      GLOB = '**/*.{rb,erb}'
+
+      # Expand includes and filter by excludes
+      #
+      # @return [Set<Pathname>]
+      #
+      # @api private
+      def call
+        include_set - exclude_set
+      end
+
+    private
+
+      # Set of excluded files
+      #
+      # @return [Set<Pathname>]
+      #
+      # @api private
+      def exclude_set
+        excludes.flat_map(&Pathname.method(:glob))
+      end
+
+      # Set of included files
+      #
+      # Expanded using flay's file expander which takes into
+      # account flay's plugin support
+      #
+      # @return [Set<Pathname>]
+      #
+      # @api private
+      def include_set
+        Set.new(flay_includes.map(&method(:Pathname)))
+      end
+
+      # Expand includes using flay
+      #
+      # Expanded using flay's file expander which takes into
+      # account flay's plugin support
+      #
+      # @return [Array<String>]
+      #
+      # @api private
+      def flay_includes
+        PathExpander.new(includes.dup, GLOB).process
+      end
+    end
+  end
+end

devtools/lib/devtools/project.rb

@@ -0,0 +1,80 @@
+module Devtools
+
+  # The project devtools supports
+  class Project
+    include Concord.new(:root)
+
+    CONFIGS = {
+      devtools:  Config::Devtools,
+      flay:      Config::Flay,
+      flog:      Config::Flog,
+      reek:      Config::Reek,
+      mutant:    Config::Mutant,
+      rubocop:   Config::Rubocop,
+      yardstick: Config::Yardstick
+    }.freeze
+
+    private_constant(*constants(false))
+
+    attr_reader(*CONFIGS.keys)
+
+    # The spec root
+    #
+    # @return [Pathname]
+    #
+    # @api private
+    attr_reader :spec_root
+
+    # Initialize object
+    #
+    # @param [Pathname] root
+    #
+    # @return [undefined]
+    #
+    # @api private
+    #
+    def initialize(root)
+      super(root)
+
+      initialize_environment
+      initialize_configs
+    end
+
+    # Init rspec
+    #
+    # @return [self]
+    #
+    # @api private
+    def init_rspec
+      Initializer::Rspec.call(self)
+      self
+    end
+
+  private
+
+    # Initialize environment
+    #
+    # @return [undefined]
+    #
+    # @api private
+    #
+    def initialize_environment
+      @spec_root = root.join(SPEC_DIRECTORY_NAME)
+    end
+
+    # Initialize configs
+    #
+    # @return [undefined]
+    #
+    # @api private
+    #
+    def initialize_configs
+      config_dir = root.join(DEFAULT_CONFIG_DIR_NAME)
+
+      CONFIGS.each do |name, klass|
+        instance_variable_set(:"@#{name}", klass.new(config_dir))
+      end
+    end
+
+  end # class Project
+end # module Devtools

devtools/lib/devtools/project/initializer.rb

@@ -0,0 +1,11 @@
+module Devtools
+  class Project
+
+    # Base class for project initializers
+    class Initializer
+      include AbstractType
+
+      abstract_singleton_method :call
+    end # class Initializer
+  end # class Project
+end # module Devtools

devtools/lib/devtools/project/initializer/rake.rb

@@ -0,0 +1,23 @@
+module Devtools
+  class Project
+    class Initializer
+      # Imports all devtools rake tasks into a project
+      class Rake < self
+        include AbstractType
+
+        # Initialize rake tasks
+        #
+        # @return [undefined]
+        #
+        # @api rpivate
+        def self.call
+          FileList
+            .glob(RAKE_FILES_GLOB)
+            .each(&::Rake.application.method(:add_import))
+          self
+        end
+
+      end # class Rake
+    end # class Initializer
+  end # class Project
+end # module Devtools

devtools/lib/devtools/project/initializer/rspec.rb

@@ -0,0 +1,80 @@
+module Devtools
+  class Project
+    class Initializer
+
+      # Requires all shared specs in a project's spec_helper
+      # Also installs a configurable unit test timeout
+      class Rspec < self
+        include Concord.new(:project)
+
+        # Call initializer for project
+        #
+        # @param [Project] project
+        #
+        # @return [self]
+        #
+        # @api private
+        def self.call(project)
+          new(project).__send__(:call)
+          self
+        end
+
+      private
+
+        # Setup RSpec for project
+        #
+        # @return [self]
+        #
+        # @api private
+        def call
+          require_shared_spec_files
+          enable_unit_test_timeout
+        end
+
+        # Timeout unit tests that take longer than configured amount of time
+        #
+        # @param [Numeric] timeout
+        #
+        # @return [undefined]
+        #
+        # @raise [Timeout::Error]
+        #   raised when the times are outside the timeout
+        #
+        # @api private
+        #
+        def enable_unit_test_timeout
+          timeout = project.devtools.unit_test_timeout
+          RSpec
+            .configuration
+            .around(file_path: UNIT_TEST_PATH_REGEXP) do |example|
+            Timeout.timeout(timeout, &example)
+          end
+        end
+
+        # Trigger the require of shared spec files
+        #
+        # @return [undefined]
+        #
+        # @api private
+        #
+        def require_shared_spec_files
+          require_files(SHARED_SPEC_PATH)
+          require_files(project.spec_root)
+        end
+
+        # Require files with pattern
+        #
+        # @param [Pathname] dir
+        #   the directory containing the files to require
+        #
+        # @return [self]
+        #
+        # @api private
+        def require_files(dir)
+          Dir.glob(dir.join(SHARED_SPEC_PATTERN)).each(&Kernel.method(:require))
+        end
+
+      end # class Rspec
+    end # class Initializer
+  end # class Project
+end # module Devtools

devtools/lib/devtools/rake/flay.rb

@@ -0,0 +1,155 @@
+# frozen_string_literal: true
+
+module Devtools
+  module Rake
+    # Flay metric runner
+    class Flay
+      include Anima.new(:threshold, :total_score, :lib_dirs, :excludes),
+              Procto.call(:verify),
+              Adamantium
+
+      BELOW_THRESHOLD = 'Adjust flay threshold down to %<mass>d'
+      TOTAL_MISMATCH  = 'Flay total is now %<mass>d, but expected %<expected>d'
+      ABOVE_THRESHOLD = '%<mass>d chunks have a duplicate mass > %<threshold>d'
+
+      # Verify code specified by `files` does not violate flay expectations
+      #
+      # @raise [SystemExit] if a violation is found
+      # @return [undefined] otherwise
+      #
+      #
+      # @api private
+      def verify
+        # Run flay first to ensure the max mass matches the threshold
+        below_threshold_message if below_threshold?
+
+        total_mismatch_message if total_mismatch?
+
+        # Run flay a second time with the threshold set
+        return unless above_threshold?
+
+        restricted_flay_scale.flay_report
+        above_threshold_message
+      end
+
+    private
+
+      # List of files flay will analyze
+      #
+      # @return [Set<Pathname>]
+      #
+      # @api private
+      def files
+        Devtools::Flay::FileList.call(lib_dirs, excludes)
+      end
+
+      # Is there mass duplication which exceeds specified `threshold`
+      #
+      # @return [Boolean]
+      #
+      # @api private
+      def above_threshold?
+        restricted_mass_size.nonzero?
+      end
+
+      # Is the specified `threshold` greater than the largest flay mass
+      #
+      # @return [Boolean]
+      #
+      # @api private
+      def below_threshold?
+        threshold > largest_mass
+      end
+
+      # Is the expected mass total different from the actual mass total
+      #
+      # @return [Boolean]
+      #
+      # @api private
+      def total_mismatch?
+        !total_mass.equal?(total_score)
+      end
+
+      # Above threshold message
+      #
+      # @return [String]
+      #
+      # @api private
+      def above_threshold_message
+        format_values = { mass: restricted_mass_size, threshold: threshold }
+        Devtools.notify_metric_violation(
+          format(ABOVE_THRESHOLD, format_values)
+        )
+      end
+
+      # Below threshold message
+      #
+      # @return [String]
+      #
+      # @api private
+      def below_threshold_message
+        Devtools.notify_metric_violation(
+          format(BELOW_THRESHOLD, mass: largest_mass)
+        )
+      end
+
+      # Total mismatch message
+      #
+      # @return [String]
+      #
+      # @api private
+      def total_mismatch_message
+        Devtools.notify_metric_violation(
+          format(TOTAL_MISMATCH, mass: total_mass, expected: total_score)
+        )
+      end
+
+      # Size of mass measured by `Flay::Scale` and filtered by `threshold`
+      #
+      # @return [Integer]
+      #
+      # @api private
+      def restricted_mass_size
+        restricted_flay_scale.measure.size
+      end
+
+      # Sum of all flay mass
+      #
+      # @return [Integer]
+      #
+      # @api private
+      def total_mass
+        flay_masses.reduce(:+).to_i
+      end
+
+      # Largest flay mass found
+      #
+      # @return [Integer]
+      #
+      # @api private
+      def largest_mass
+        flay_masses.max.to_i
+      end
+
+      # Flay scale which only measures mass above `threshold`
+      #
+      # @return [Flay::Scale]
+      #
+      # @api private
+      def restricted_flay_scale
+        Devtools::Flay::Scale.new(minimum_mass: threshold.succ, files: files)
+      end
+      memoize :restricted_flay_scale
+
+      # All flay masses found in `files`
+      #
+      # @return [Array<Rational>]
+      #
+      # @api private
+      def flay_masses
+        Devtools::Flay::Scale.call(minimum_mass: 0, files: files)
+      end
+      memoize :flay_masses
+    end
+  end
+end

devtools/lib/devtools/spec_helper.rb

@@ -0,0 +1,3 @@
+require 'devtools'
+
+Devtools::PROJECT.init_rspec

devtools/shared/spec/shared/abstract_type_behavior.rb

@@ -0,0 +1,16 @@
+shared_examples_for 'an abstract type' do
+  context 'called on a subclass' do
+    let(:object) { Class.new(described_class) }
+
+    it { should be_instance_of(object) }
+  end
+
+  context 'called on the class' do
+    let(:object) { described_class }
+
+    specify do
+      expect { subject }
+        .to raise_error(NotImplementedError, "#{object} is an abstract type")
+    end
+  end
+end

devtools/shared/spec/shared/command_method_behavior.rb

@@ -0,0 +1,5 @@
+shared_examples_for 'a command method' do
+  it 'returns self' do
+    should equal(object)
+  end
+end

devtools/shared/spec/shared/each_method_behaviour.rb

@@ -0,0 +1,13 @@
+shared_examples_for 'an #each method' do
+  it_should_behave_like 'a command method'
+
+  context 'with no block' do
+    subject { object.each }
+
+    it { should be_instance_of(to_enum.class) }
+
+    it 'yields the expected values' do
+      expect(subject.to_a).to eql(object.to_a)
+    end
+  end
+end

devtools/shared/spec/shared/idempotent_method_behavior.rb

@@ -0,0 +1,11 @@
+shared_examples_for 'an idempotent method' do
+  it 'is idempotent' do
+    first = subject
+    error = 'RSpec not configured for threadsafety'
+    fail error unless RSpec.configuration.threadsafe?
+    mutex = __memoized.instance_variable_get(:@mutex)
+    memoized = __memoized.instance_variable_get(:@memoized)
+    mutex.synchronize { memoized.delete(:subject) }
+    should equal(first)
+  end
+end

devtools/shared/spec/support/ice_nine_config.rb

@@ -0,0 +1,12 @@
+if defined?(IceNine)
+  module IceNine
+
+    # Freezer namespace
+    class Freezer
+
+      # Rspec freezer
+      class RSpec < NoFreeze; end
+
+    end # Freezer
+  end # IceNine
+end

devtools/spec/integration/devtools/rake/flay/verify_spec.rb

@@ -0,0 +1,196 @@
+# frozen_string_literal: true
+
+describe Devtools::Rake::Flay, '#verify' do
+  let(:tempfile)    { Tempfile.new(%w[file .rb], Dir.mktmpdir) }
+  let(:file)        { Pathname(tempfile.path)                  }
+  let(:directories) { [file.dirname.to_s]                      }
+
+  let(:ruby) do
+    <<-ERUBY
+    def foo; end
+    def bar; end
+    ERUBY
+  end
+
+  around(:each) do |example|
+    begin
+      # silence other flay output
+      $stdout = $stderr = StringIO.new
+
+      tempfile.write(ruby)
+      tempfile.close
+
+      example.run
+    ensure
+      $stdout = STDOUT
+      $stderr = STDERR
+
+      file.unlink
+    end
+  end
+
+  context 'reporting' do
+    let(:options) do
+      { threshold: 3, total_score: 3, lib_dirs: directories, excludes: [] }
+    end
+
+    let(:instance) { described_class.new(options) }
+
+    it 'measures total mass' do
+      allow(::Flay).to receive(:new).and_call_original
+
+      instance.verify
+
+      expect(::Flay).to have_received(:new).with(hash_including(mass: 0))
+    end
+
+    it 'does not report the files it is processing' do
+      expect { instance.verify }.to_not output(/Processing #{file}/).to_stderr
+    end
+  end
+
+  context 'when theshold is too low' do
+    let(:instance) do
+      described_class.new(
+        threshold: 0,
+        total_score: 0,
+        lib_dirs: directories,
+        excludes: []
+      )
+    end
+
+    specify do
+      expect { instance.verify }
+        .to raise_error(SystemExit)
+        .with_message('Flay total is now 3, but expected 0')
+    end
+  end
+
+  context 'when threshold is too high' do
+    let(:instance) do
+      described_class.new(
+        threshold: 1000,
+        total_score: 0,
+        lib_dirs: directories,
+        excludes: []
+      )
+    end
+
+    specify do
+      expect { instance.verify }
+        .to raise_error(SystemExit)
+        .with_message('Adjust flay threshold down to 3')
+    end
+  end
+
+  context 'when total is too high' do
+    let(:instance) do
+      described_class.new(
+        threshold: 3,
+        total_score: 50,
+        lib_dirs: directories,
+        excludes: []
+      )
+    end
+
+    specify do
+      expect { instance.verify }
+        .to raise_error(SystemExit)
+        .with_message('Flay total is now 3, but expected 50')
+    end
+  end
+
+  context 'when duplicate mass is greater than 0' do
+    let(:ruby) do
+      <<-ERUBY
+      def foo
+        :hi if baz?
+      end
+
+      def bar
+        :hi if baz?
+      end
+      ERUBY
+    end
+
+    let(:report) do
+      <<~REPORT
+        Total score (lower is better) = 10
+
+        1) Similar code found in :defn (mass = 10)
+          #{file}:1
+          #{file}:5
+      REPORT
+    end
+
+    let(:instance) do
+      described_class.new(
+        threshold: 3,
+        total_score: 5,
+        lib_dirs: directories,
+        excludes: []
+      )
+    end
+
+    specify do
+      expect { instance.verify }
+        .to raise_error(SystemExit)
+        .with_message('1 chunks have a duplicate mass > 3')
+    end
+
+    specify do
+      expect { instance.verify }
+        .to raise_error(SystemExit)
+        .and output(report).to_stdout
+    end
+  end
+
+  context 'when multiple duplicate masses' do
+    let(:ruby) do
+      <<-ERUBY
+      def foo; end
+      def bar; end
+
+      class Foo
+        def initialize
+          @a = 1
+        end
+      end
+      class Bar
+        def initialize
+          @a = 1
+        end
+      end
+      ERUBY
+    end
+
+    let(:instance) do
+      described_class.new(
+        threshold: 5,
+        total_score: 8,
+        lib_dirs: directories,
+        excludes: []
+      )
+    end
+
+    it 'sums masses for total' do
+      expect { instance.verify }.to_not raise_error
+    end
+  end
+
+  context 'when no duplication masses' do
+    let(:ruby) { '' }
+    let(:instance) do
+      described_class.new(
+        threshold: 0,
+        total_score: 0,
+        lib_dirs: directories,
+        excludes: []
+      )
+    end
+
+    specify do
+      expect { instance.verify }.to_not raise_error
+    end
+  end
+end

devtools/spec/spec_helper.rb

@@ -0,0 +1,24 @@
+require 'devtools/spec_helper'
+require 'tempfile'
+require 'tmpdir'
+
+if ENV['COVERAGE'] == 'true'
+  formatter = [SimpleCov::Formatter::HTMLFormatter]
+  SimpleCov.formatter = SimpleCov::Formatter::MultiFormatter.new(formatter)
+
+  SimpleCov.start do
+    command_name 'spec:unit'
+
+    add_filter 'config'
+    add_filter 'spec'
+    add_filter 'vendor'
+
+    minimum_coverage 100
+  end
+end
+
+RSpec.configure do |config|
+  config.expect_with :rspec do |expect_with|
+    expect_with.syntax = :expect
+  end
+end

devtools/spec/unit/devtools/config/yardstick_spec.rb

@@ -0,0 +1,17 @@
+RSpec.describe Devtools::Config::Yardstick do
+  let(:object) { described_class.new(Devtools.root.join('config')) }
+
+  describe '#options' do
+    subject { object.options }
+
+    specify do
+      should eql(
+        'threshold'               => 100,
+        'rules'                   => nil,
+        'verbose'                 => nil,
+        'path'                    => nil,
+        'require_exact_threshold' => nil
+      )
+    end
+  end
+end

devtools/spec/unit/devtools/config_spec.rb

@@ -0,0 +1,78 @@
+RSpec.describe Devtools::Config do
+
+  describe '.attribute' do
+    let(:raw) do
+      {
+        'a' => 'bar',
+        'c' => []
+      }
+
+    end
+
+    let(:config_path) { instance_double(Pathname) }
+
+    let(:class_under_test) do
+      expect(config_path).to receive(:file?)
+        .and_return(file?)
+      expect(config_path).to receive(:frozen?)
+        .and_return(true)
+      expect(config_path).to receive(:join)
+        .with('bar.yml')
+        .and_return(config_path)
+
+      Class.new(described_class) do
+        attribute :a, [String]
+        attribute :b, [Array], default: []
+        attribute :c, [TrueClass, FalseClass]
+
+        const_set(:FILE, 'bar.yml')
+      end
+    end
+
+    subject do
+      class_under_test.new(config_path)
+    end
+
+    context 'on present config' do
+      let(:class_under_test) do
+        # Setup message expectation in a lasy way, not in a before
+        # block to make sure the around hook setting timeouts from the
+        # code under test is not affected.
+        expect(YAML).to receive(:load_file)
+          .with(config_path)
+          .and_return(raw)
+
+        expect(IceNine).to receive(:deep_freeze)
+          .with(raw)
+          .and_return(raw)
+
+        super()
+      end
+
+      let(:file?) { true }
+
+      it 'allows to receive existing keys' do
+        expect(subject.a).to eql('bar')
+      end
+
+      it 'allows to receive absent keys with defaults' do
+        expect(subject.b).to eql([])
+      end
+
+      it 'executes checks when configured' do
+        expect { subject.c }.to raise_error(
+          Devtools::Config::TypeError,
+          'c: Got instance of Array expected TrueClass,FalseClass'
+        )
+      end
+    end
+
+    context 'on absent config' do
+      let(:file?) { false }
+
+      it 'defaults to absent keys' do
+        expect(subject.b).to eql([])
+      end
+    end
+  end
+end

devtools/spec/unit/devtools/flay/file_list/call_spec.rb

@@ -0,0 +1,19 @@
+describe Devtools::Flay::FileList, '.call' do
+  subject(:output) { described_class.call([tmpdir.to_s].freeze, [exclude]) }
+
+  let(:tmpdir)     { Dir.mktmpdir                     }
+  let(:one)        { Pathname(tmpdir).join('1.rb')    }
+  let(:two)        { Pathname(tmpdir).join('2.erb')   }
+  let(:three)      { Pathname(tmpdir).join('3.rb')    }
+  let(:exclude)    { Pathname(tmpdir).join('3*').to_s }
+
+  around(:each) do |example|
+    [one, two, three].map(&FileUtils.method(:touch))
+
+    example.run
+
+    FileUtils.rm_rf(tmpdir)
+  end
+
+  it { should eql(Set.new([one, two])) }
+end

devtools/spec/unit/devtools/flay/scale/flay_report_spec.rb

@@ -0,0 +1,17 @@
+describe Devtools::Flay::Scale, '#flay_report' do
+  subject(:instance) { described_class.new(minimum_mass: 0, files: []) }
+
+  let(:flay) do
+    instance_double(::Flay, process: nil, analyze: nil, masses: {})
+  end
+
+  before do
+    allow(::Flay).to receive(:new).with(mass: 0).and_return(flay)
+  end
+
+  specify do
+    allow(flay).to receive(:report)
+    instance.flay_report
+    expect(flay).to have_received(:report)
+  end
+end

devtools/spec/unit/devtools/flay/scale/measure_spec.rb

@@ -0,0 +1,43 @@
+describe Devtools::Flay::Scale, '#measure' do
+  subject(:measure) { instance.measure }
+
+  let(:minimum_mass) { 0 }
+  let(:files)        { [instance_double(File)] }
+  let(:flay_masses) { { 0 => 5, 1 => 10 } }
+
+  let(:instance) do
+    described_class.new(minimum_mass: minimum_mass, files: files)
+  end
+
+  let(:flay_hashes) do
+    {
+      0 => instance_double(Array, size: 3),
+      1 => instance_double(Array, size: 11)
+    }
+  end
+
+  let(:flay) do
+    instance_double(
+      ::Flay,
+      analyze: nil,
+      masses:  flay_masses,
+      hashes:  flay_hashes
+    )
+  end
+
+  before do
+    allow(::Flay).to receive(:new).with(mass: minimum_mass).and_return(flay)
+    allow(flay).to receive(:process).with(*files)
+  end
+
+  it { should eql([Rational(5, 3), Rational(10, 11)]) }
+
+  context 'when minimum mass is not 0' do
+    let(:minimum_mass) { 1 }
+
+    specify do
+      measure
+      expect(::Flay).to have_received(:new).with(mass: 1)
+    end
+  end
+end

devtools/spec/unit/devtools/project/initializer/rake_spec.rb

@@ -0,0 +1,21 @@
+describe Devtools::Project::Initializer::Rake do
+  describe '.call' do
+    subject do
+      described_class.call
+    end
+
+    it 'performs expected rake initialization' do
+      path_a = instance_double(Pathname)
+      path_b = instance_double(Pathname)
+
+      expect(FileList).to receive(:glob)
+        .with(Devtools.root.join('tasks/**/*.rake').to_s)
+        .and_return([path_a, path_b])
+
+      expect(Rake.application).to receive(:add_import).with(path_a)
+      expect(Rake.application).to receive(:add_import).with(path_b)
+
+      expect(subject).to be(described_class)
+    end
+  end
+end

devtools/spec/unit/devtools/project/initializer/rspec_spec.rb

@@ -0,0 +1,52 @@
+describe Devtools::Project::Initializer::Rspec do
+  let(:spec_root)         { Devtools.root.join('spec') }
+  let(:unit_test_timeout) { instance_double(Float)     }
+
+  let(:project) do
+    instance_double(
+      Devtools::Project,
+      spec_root: spec_root,
+      devtools:  instance_double(
+        Devtools::Config::Devtools,
+        unit_test_timeout: unit_test_timeout
+      )
+    )
+  end
+
+  describe '.call' do
+    subject do
+      described_class.call(project)
+    end
+
+    it 'performs expected rspec initialization' do
+      called = false
+      example = -> { called = true }
+
+      expect(Dir).to receive(:glob)
+        .with(Devtools.root.join('shared/spec/{shared,support}/**/*.rb'))
+        .and_return(%w[shared-a shared-b])
+
+      expect(Kernel).to receive(:require).with('shared-a')
+      expect(Kernel).to receive(:require).with('shared-b')
+
+      expect(Dir).to receive(:glob)
+        .with(Devtools.root.join('spec/{shared,support}/**/*.rb'))
+        .and_return(%w[support-a support-b])
+
+      expect(Kernel).to receive(:require).with('support-a')
+      expect(Kernel).to receive(:require).with('support-b')
+
+      expect(Timeout).to receive(:timeout).with(unit_test_timeout) do |&block|
+        block.call
+      end
+
+      expect(RSpec.configuration).to receive(:around)
+        .with(file_path: %r{\bspec/unit/})
+        .and_yield(example)
+
+      expect(subject).to be(described_class)
+
+      expect(called).to be(true)
+    end
+  end
+end

devtools/spec/unit/devtools/project_spec.rb

@@ -0,0 +1,35 @@
+RSpec.describe Devtools::Project do
+  let(:object) { described_class.new(Devtools.root) }
+
+  describe '#init_rspec' do
+    subject { object.init_rspec }
+
+    it 'calls the rspec initializer' do
+      expect(Devtools::Project::Initializer::Rspec)
+        .to receive(:call).with(Devtools.project)
+      expect(subject).to be(object)
+    end
+  end
+
+  {
+    devtools:  Devtools::Config::Devtools,
+    flay:      Devtools::Config::Flay,
+    flog:      Devtools::Config::Flog,
+    reek:      Devtools::Config::Reek,
+    mutant:    Devtools::Config::Mutant,
+    rubocop:   Devtools::Config::Rubocop,
+    yardstick: Devtools::Config::Yardstick
+  }.each do |name, klass|
+    describe "##{name}" do
+      subject { object.send(name) }
+
+      specify { should eql(klass.new(Devtools.root.join('config'))) }
+    end
+  end
+
+  describe '#spec_root' do
+    subject { object.spec_root }
+
+    specify { should eql(Devtools.root.join('spec')) }
+  end
+end

devtools/spec/unit/devtools_spec.rb

@@ -0,0 +1,14 @@
+describe Devtools do
+  describe '.project' do
+    specify do
+      expect(Devtools.project).to equal(Devtools::PROJECT)
+    end
+  end
+
+  describe '.init_rake_tasks' do
+    specify do
+      expect(Devtools::Project::Initializer::Rake).to receive(:call)
+      expect(Devtools.init_rake_tasks).to be(Devtools)
+    end
+  end
+end

devtools/tasks/metrics/ci.rake

@@ -0,0 +1,17 @@
+desc 'Run all specs, metrics and mutant'
+task ci: %w[ci:metrics metrics:mutant]
+
+namespace :ci do
+  tasks = %w[
+    metrics:coverage
+    metrics:yardstick:verify
+    metrics:rubocop
+    metrics:flog
+    metrics:flay
+    metrics:reek
+    spec:integration
+  ]
+
+  desc 'Run metrics (except mutant)'
+  task metrics: tasks
+end

devtools/tasks/metrics/coverage.rake

@@ -0,0 +1,13 @@
+namespace :metrics do
+  desc 'Measure code coverage'
+  task :coverage do
+    begin
+      # rubocop:disable Style/ParallelAssignment
+      original, ENV['COVERAGE'] = ENV['COVERAGE'], 'true'
+      # rubocop:enable Style/ParallelAssignment
+      Rake::Task['spec:unit'].execute
+    ensure
+      ENV['COVERAGE'] = original
+    end
+  end
+end

devtools/tasks/metrics/flay.rake

@@ -0,0 +1,21 @@
+namespace :metrics do
+  require 'flay'
+
+  project = Devtools.project
+  config  = project.flay
+
+  # Original code by Marty Andrews:
+  # http://blog.martyandrews.net/2009/05/enforcing-ruby-code-quality.html
+  desc 'Measure code duplication'
+  task :flay do
+    threshold   = config.threshold
+    total_score = config.total_score
+
+    Devtools::Rake::Flay.call(
+      threshold:   threshold,
+      total_score: total_score,
+      lib_dirs:    config.lib_dirs,
+      excludes:    config.excludes
+    )
+  end
+end

devtools/tasks/metrics/flog.rake

@@ -0,0 +1,43 @@
+# rubocop:disable Metrics/BlockLength
+namespace :metrics do
+  require 'flog'
+  require 'flog_cli'
+
+  project = Devtools.project
+  config  = project.flog
+
+  # Original code by Marty Andrews:
+  # http://blog.martyandrews.net/2009/05/enforcing-ruby-code-quality.html
+  desc 'Measure code complexity'
+  task :flog do
+    threshold = config.threshold.to_f.round(1)
+    flog      = Flog.new
+    flog.flog(*PathExpander.new(config.lib_dirs.dup, '**/*.rb').process)
+
+    totals = flog
+      .totals
+      .reject  { |name, _score| name.end_with?('#none') }
+      .map     { |name, score| [name, score.round(1)]   }
+      .sort_by { |_name, score| score                   }
+
+    if totals.any?
+      max = totals.last[1]
+      unless max >= threshold
+        Devtools.notify_metric_violation "Adjust flog score down to #{max}"
+      end
+    end
+
+    bad_methods = totals.select { |_name, score| score > threshold }
+
+    if bad_methods.any?
+      bad_methods.reverse_each do |name, score|
+        printf "%8.1f: %s\n", score, name
+      end
+
+      Devtools.notify_metric_violation(
+        "#{bad_methods.size} methods have a flog complexity > #{threshold}"
+      )
+    end
+  end
+end
+# rubocop:enable Metrics/BlockLength

devtools/tasks/metrics/mutant.rake

@@ -0,0 +1,43 @@
+# rubocop:disable Metrics/BlockLength
+namespace :metrics do
+  config = Devtools.project.mutant
+
+  desc 'Measure mutation coverage'
+  task mutant: :coverage do
+    require 'mutant'
+
+    namespace =
+      if config.zombify
+        Mutant.zombify
+        Zombie::Mutant
+      else
+        Mutant
+      end
+
+    namespaces = Array(config.namespace).map { |n| "#{n}*" }
+
+    ignore_subjects = config.ignore_subjects.flat_map do |matcher|
+      %W[--ignore #{matcher}]
+    end
+
+    jobs = ENV.key?('CIRCLECI') ? %w[--jobs 4] : []
+
+    since =
+      if config.since
+        %W[--since #{config.since}]
+      else
+        []
+      end
+
+    arguments = %W[
+      --include lib
+      --require #{config.name}
+      --use #{config.strategy}
+    ].concat(ignore_subjects).concat(namespaces).concat(since).concat(jobs)
+
+    unless namespace::CLI.run(arguments)
+      Devtools.notify_metric_violation('Mutant task is not successful')
+    end
+  end
+end
+# rubocop:enable Metrics/BlockLength

devtools/tasks/metrics/reek.rake

@@ -0,0 +1,8 @@
+namespace :metrics do
+  require 'reek/rake/task'
+
+  Reek::Rake::Task.new do |reek|
+    reek.source_files = '{app,lib}/**/*.rb'
+    reek.config_file  = 'config/reek.yml'
+  end
+end

devtools/tasks/metrics/rubocop.rake

@@ -0,0 +1,13 @@
+namespace :metrics do
+  desc 'Check with code style guide'
+  task :rubocop do
+    require 'rubocop'
+    config = Devtools.project.rubocop
+    begin
+      exit_status = RuboCop::CLI.new.run(%W[--config #{config.config_file}])
+      fail 'Rubocop not successful' unless exit_status.zero?
+    rescue Encoding::CompatibilityError => exception
+      Devtools.notify_metric_violation exception.message
+    end
+  end
+end

devtools/tasks/metrics/yardstick.rake

@@ -0,0 +1,12 @@
+namespace :metrics do
+  namespace :yardstick do
+    require 'yardstick/rake/measurement'
+    require 'yardstick/rake/verify'
+
+    options = Devtools.project.yardstick.options
+
+    Yardstick::Rake::Measurement.new(:measure, options)
+
+    Yardstick::Rake::Verify.new(:verify, options)
+  end
+end

devtools/tasks/spec.rake

@@ -0,0 +1,34 @@
+begin
+  require 'rspec/core/rake_task'
+
+  # Remove existing same-named tasks
+  %w[spec spec:unit spec:integration].each do |task|
+    klass = Rake::Task
+    klass[task].clear if klass.task_defined?(task)
+  end
+
+  desc 'Run all specs'
+  RSpec::Core::RakeTask.new(:spec) do |task|
+    task.pattern = 'spec/{unit,integration}/**/*_spec.rb'
+  end
+
+  namespace :spec do
+    desc 'Run unit specs'
+    RSpec::Core::RakeTask.new(:unit) do |task|
+      task.pattern = 'spec/unit/**/*_spec.rb'
+    end
+
+    desc 'Run integration specs'
+    RSpec::Core::RakeTask.new(:integration) do |task|
+      task.pattern = 'spec/integration/**/*_spec.rb'
+    end
+  end
+rescue LoadError
+  %w[spec spec:unit spec:integration].each do |name|
+    task name do
+      warn "In order to run #{name}, do: gem install rspec"
+    end
+  end
+end
+
+task test: :spec

devtools/tasks/yard.rake

@@ -0,0 +1,9 @@
+begin
+  require 'yard'
+
+  YARD::Rake::YardocTask.new
+rescue LoadError
+  task :yard do
+    warn 'In order to run yard, you must: gem install yard'
+  end
+end

mutant.gemspec

@@ -36,6 +36,5 @@ Gem::Specification.new do |gem|
   gem.add_runtime_dependency('regexp_parser', '~> 1.2')
   gem.add_runtime_dependency('unparser',      '~> 0.4.2')
 
-  gem.add_development_dependency('devtools', '~> 0.1.22')
   gem.add_development_dependency('parallel', '~> 1.3')
 end