diff --git a/.rubocop.yml b/.rubocop.yml
index acdf2e117..84d6a7c5b 100644
--- a/.rubocop.yml
+++ b/.rubocop.yml
@@ -4,8 +4,9 @@ AllCops:
   Exclude:
     - doc/**/*.rb
     - rake.gemspec
+    - bin/*
 
-Style/LineLength:
+Metrics/LineLength:
   Enabled: true
   Max: 120
 
@@ -16,42 +17,42 @@ Style/StringLiterals:
   Enabled: true
   EnforcedStyle: double_quotes
 
-Style/IndentationWidth:
+Style/MultilineIfThen:
   Enabled: true
 
-Style/Tab:
+Style/MethodDefParentheses:
   Enabled: true
 
-Style/EmptyLines:
+Style/BracesAroundHashParameters:
   Enabled: true
 
-Style/TrailingBlankLines:
+Layout/IndentationWidth:
   Enabled: true
 
-Style/TrailingWhitespace:
+Layout/Tab:
   Enabled: true
 
-Style/SpaceBeforeBlockBraces:
+Layout/EmptyLines:
   Enabled: true
 
-Style/SpaceInsideBlockBraces:
+Layout/TrailingBlankLines:
   Enabled: true
 
-Style/SpaceInsideHashLiteralBraces:
+Layout/TrailingWhitespace:
   Enabled: true
 
-Style/CaseIndentation:
+Layout/SpaceBeforeBlockBraces:
   Enabled: true
 
-Style/MultilineIfThen:
+Layout/SpaceInsideBlockBraces:
   Enabled: true
 
-Style/MethodDefParentheses:
+Layout/SpaceInsideHashLiteralBraces:
   Enabled: true
 
-Style/BracesAroundHashParameters:
+Layout/CaseIndentation:
   Enabled: true
 
-Lint/EndAlignment:
+Layout/EndAlignment:
   Enabled: true
-  AlignWith: variable
+  EnforcedStyleAlignWith: variable
diff --git a/.travis.yml b/.travis.yml
index 6e1db29fe..b0bf3ebe3 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,21 +1,24 @@
 language: ruby
-sudo: false
 rvm:
-  - 1.9.3
   - 2.0.0
   - 2.1.10
-  - 2.2.5
-  - 2.3.1
+  - 2.2.10
+  - 2.3.8
+  - 2.4.5
+  - 2.5.3
+  - 2.6.1
   - ruby-head
-  - jruby-1.7.20
-  - jruby-9.1.6.0
+  - jruby-9.2.4.0
   - jruby-head
-before_install:
-  - gem install bundler --no-document -v '~> 1.13.3'
+
+matrix:
+  include:
+    - rvm: 2.5.3
+      env: COVERALLS=yes
+
 before_script:
   - unset JRUBY_OPTS
+  - unset _JAVA_OPTIONS
+  - if ruby -e "exit RUBY_VERSION >= '2.3.0'"; then gem update --system=3.0.1; else gem update --system=2.7.8; fi
+
 script: ruby -Ilib exe/rake
-notifications:
-  email:
-  - hsbt@ruby-lang.org
-  - drbrain@segment7.net
diff --git a/CONTRIBUTING.rdoc b/CONTRIBUTING.rdoc
index d68e8c525..e8430ddb4 100644
--- a/CONTRIBUTING.rdoc
+++ b/CONTRIBUTING.rdoc
@@ -3,7 +3,7 @@
 Rake is currently hosted at github. The github web page is
 https://github.com/ruby/rake . The public git clone URL is
 
-  git://github.com/ruby/rake.git
+  https://github.com/ruby/rake.git
 
 = Running the Rake Test Suite
 
@@ -12,11 +12,18 @@ If you wish to run the unit and functional tests that come with Rake:
 * +cd+ into the top project directory of rake.
 * Install gem dependency using bundler:
 
-    bundle install  # Install bundler, minitest and rdoc
+    $ bundle install  # Install bundler, minitest and rdoc
 
-* Type one of the following:
+* Run the test suite
 
-    rake            # If you have run rake's tests
+    $ rake
+
+= Rubocop
+
+Rake uses Rubocop to enforce a consistent style on new changes being
+proposed. You can check your code with Rubocop using:
+
+  $ ./bin/rubocop
 
 = Issues and Bug Reports
 
diff --git a/History.rdoc b/History.rdoc
index 16c62c8b2..16b6331a1 100644
--- a/History.rdoc
+++ b/History.rdoc
@@ -1,10 +1,107 @@
+=== 12.3.3
+
+==== Bug fixes
+
+* Use the application's name in error message if a task is not found.
+  Pull Request #303 by tmatilai
+
+==== Enhancements:
+
+* Use File.open explicitly.
+
+=== 12.3.2
+
+==== Bug fixes
+
+* Fixed test fails caused by 2.6 warnings.
+  Pull Request #297 by hsbt
+
+==== Enhancements:
+
+* Rdoc improvements.
+  Pull Request #293 by colby-swandale
+* Improve multitask performance.
+  Pull Request #273 by jsm
+* Add alias `prereqs`.
+  Pull Request #268 by take-cheeze
+
+=== 12.3.1
+
+==== Bug fixes
+
+* Support did_you_mean >= v1.2.0 which has a breaking change on formatters.
+  Pull request #262 by FUJI Goro.
+
+==== Enhancements:
+
+* Don't run task if it depends on already invoked but failed task.
+  Pull request #252 by Gonzalo Rodriguez.
+* Make space trimming consistent for all task arguments.
+  Pull request #259 by Gonzalo Rodriguez.
+* Removes duplicated inclusion of Rake::DSL in tests.
+  Pull request #254 by Gonzalo Rodriguez.
+* Re-raise a LoadError that didn't come from require in the test loader.
+  Pull request #250 by Dylan Thacker-Smith.
+
+=== 12.3.0
+
+==== Compatibility Changes
+
+* Bump `required_ruby_version` to Ruby 2.0.0. Rake has already
+  removed support for Ruby 1.9.x.
+
+==== Enhancements:
+
+* Support `test-bundled-gems` task on ruby core.
+
+=== 12.2.1
+
+==== Bug fixes
+
+* Fixed to break Capistrano::Application on capistrano3.
+
+=== 12.2.0
+
+==== Enhancements:
+
+* Make rake easier to use as a library
+  Pull request #211 by @drbrain
+* Fix quadratic performance in FileTask#out_of_date?
+  Pull request #224 by @doudou
+* Clarify output when printing nested exception traces
+  Pull request #232 by @urbanautomaton
+
+==== Bug fixes
+
+* Account for a file that match 2 or more patterns.
+  Pull request #231 by @styd
+
+=== 12.1.0
+
+==== Enhancements:
+
+* Added did_you_mean feature for invalid rake task.
+  Pull request #221 by @xtina-starr
+* Enabled to dependency chained by extensions. Pull request #39 by Petr Skocik.
+* Make all of string literals to frozen objects on Ruby 2.4 or later.
+
+==== Bug fixes
+
+* Typo fixes in rakefile.rdoc. Pull request #180 by Yuta Kurotaki.
+* Fix unexpected behavior of file task with dryrun option.
+  Pull request #183 by @aycabta.
+* Make LoadError from running tests more obvious. Pull request #195
+  by Eric Hodel.
+* Fix unexpected TypeError with hash style option. Pull request #202
+  by Kuniaki IGARASHI.
+
 === 12.0.0
 
 ==== Compatibility Changes
 
-* Remove arguments on clear #157 by Jesse Bowes
+* Removed arguments on clear #157 by Jesse Bowes
 * Removed `rake/contrib` packages. These are extracted to `rake-contrib` gem.
-* Removed to deprecated warnings for `last\_comment`.
+* Removed deprecated method named `last\_comment`.
 
 ==== Enhancements:
 
@@ -385,7 +482,7 @@ we'll repeat the changes for versions 0.9.3 through 0.9.5 here.
   programatically add rake task libraries.
 
 * You can specific backtrace suppression patterns (see
-  --supress-backtrace)
+  --suppress-backtrace)
 
 * Directory tasks can now take prerequisites and actions
 
@@ -633,7 +730,7 @@ we'll repeat the changes for version 0.9.3 here.
   programatically add rake task libraries.
 
 * You can specific backtrace suppression patterns (see
-  --supress-backtrace)
+  --suppress-backtrace)
 
 * Directory tasks can now take prerequisites and actions
 
@@ -843,7 +940,7 @@ a number of bug fixes.
   programatically add rake task libraries.
 
 * You can specific backtrace suppression patterns (see
-  --supress-backtrace)
+  --suppress-backtrace)
 
 * Directory tasks can now take prerequisites and actions
 
@@ -1415,7 +1512,7 @@ The first argument is still the name of the task (:name in this case).
 The next to argumements are the names of the parameters expected by
 :name (:first_name and :last_name in the example).
 
-To access the values of the paramters, the block defining the task
+To access the values of the parameters, the block defining the task
 behaviour can now accept a second parameter:
 
    task :name, :first_name, :last_name do |t, args|
@@ -1518,7 +1615,7 @@ The first argument is still the name of the task (:name in this case).
 The next to argumements are the names of the parameters expected by
 :name (:first_name and :last_name in the example).
 
-To access the values of the paramters, the block defining the task
+To access the values of the parameters, the block defining the task
 behaviour can now accept a second parameter:
 
    task :name, :first_name, :last_name do |t, args|
@@ -1738,7 +1835,7 @@ are, I hope you enjoy them.
 * RDoc defaults to internal (in-process) invocation.  The old behavior
   is still available by setting the +external+ flag to true.
 * Rakefiles are now loaded with the expanded path to prevent
-  accidental polution from the Ruby load path.
+  accidental pollution from the Ruby load path.
 * Task objects my now be used in prerequisite lists directly.
 * Task objects (in addition to task names) may now be included in the
   prerequisite list of a task.
@@ -1751,7 +1848,7 @@ are, I hope you enjoy them.
 ===== Namespaces
 
 Tasks can now be nested inside their own namespaces.  Tasks within one
-namespace will not accidently interfer with tasks named in a different
+namespace will not accidentally interfer with tasks named in a different
 namespace.
 
 For example:
@@ -1809,7 +1906,7 @@ As usual, it was input from users that drove a alot of these changes.
 The following people either contributed patches, made suggestions or
 made otherwise helpful comments.  Thanks to ...
 
-* Doug Young (inspriation for the parallel task)
+* Doug Young (inspiration for the parallel task)
 * David Heinemeier Hansson (for --trace message enhancement and for
   pushing for namespace support).
 * Ludvig Omholt (for the openAFS fix)
diff --git a/README.rdoc b/README.rdoc
index 690c11d66..ab136b85d 100644
--- a/README.rdoc
+++ b/README.rdoc
@@ -25,8 +25,8 @@ Rake has the following features:
 
 * A library of prepackaged tasks to make building rakefiles easier. For example,
   tasks for building tarballs. (Formerly
-  tasks for building RDoc, Gems and publishing to FTP were included in rake but they're now
-  available in RDoc, RubyGems and  respectively.)
+  tasks for building RDoc, Gems, and publishing to FTP were included in rake but they're now
+  available in RDoc, RubyGems, and rake-contrib respectively.)
 
 * Supports parallel execution of tasks.
 
@@ -75,10 +75,10 @@ Type "rake --help" for all available options.
 
 === Rake Information
 
-* {Rake command-line}[rdoc-ref:doc/command_line_usage.rdoc]
-* {Writing Rakefiles}[rdoc-ref:doc/rakefile.rdoc]
-* The original {Rake announcement}[rdoc-ref:doc/rational.rdoc]
-* Rake {glossary}[rdoc-ref:doc/glossary.rdoc]
+* {Rake command-line}[link:doc/command_line_usage.rdoc]
+* {Writing Rakefiles}[link:doc/rakefile.rdoc]
+* The original {Rake announcement}[link:doc/rational.rdoc]
+* Rake {glossary}[link:doc/glossary.rdoc]
 
 === Presentations and Articles about Rake
 
@@ -130,7 +130,7 @@ Rake is available under an MIT-style license.
 = Other stuff
 
 Author::   Jim Weirich <jim.weirich@gmail.com>
-Requires:: Ruby 1.9.3 or later
+Requires:: Ruby 2.0.0 or later
 License::  Copyright Jim Weirich.
            Released under an MIT-style license.  See the MIT-LICENSE
            file included in the distribution.
diff --git a/Rakefile b/Rakefile
index e0d2ced3d..e03dc6feb 100644
--- a/Rakefile
+++ b/Rakefile
@@ -9,16 +9,19 @@
 lib = File.expand_path("../lib", __FILE__)
 $LOAD_PATH.unshift(lib) unless $LOAD_PATH.include?(lib)
 
-require "bundler/gem_tasks"
-require "rake/testtask"
-require "rdoc/task"
+begin
+  require "bundler/gem_tasks"
+rescue LoadError
+end
 
+require "rake/testtask"
 Rake::TestTask.new(:test) do |t|
   t.libs << "test"
   t.verbose = true
   t.test_files = FileList["test/**/test_*.rb"]
 end
 
+require "rdoc/task"
 RDoc::Task.new do |doc|
   doc.main   = "README.rdoc"
   doc.title  = "Rake -- Ruby Make"
@@ -27,7 +30,7 @@ RDoc::Task.new do |doc|
 end
 
 task ghpages: :rdoc do
-  `git checkout gh-pages`
+  %x[git checkout gh-pages]
   require "fileutils"
   FileUtils.rm_rf "/tmp/html"
   FileUtils.mv "html", "/tmp"
diff --git a/appveyor.yml b/appveyor.yml
index 79847873c..fa978bb4a 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -2,15 +2,13 @@
 clone_depth: 10
 install:
   - SET PATH=C:\Ruby%ruby_version%\bin;%PATH%
-  - gem install bundler --no-document
-  - bundle install
+  - gem install minitest
 build: off
 test_script:
   - ruby -Ilib exe/rake
 deploy: off
 environment:
   matrix:
-    - ruby_version: "193"
     - ruby_version: "200"
     - ruby_version: "200-x64"
     - ruby_version: "21"
@@ -19,3 +17,7 @@ environment:
     - ruby_version: "22-x64"
     - ruby_version: "23"
     - ruby_version: "23-x64"
+    - ruby_version: "24"
+    - ruby_version: "24-x64"
+    - ruby_version: "25"
+    - ruby_version: "25-x64"
diff --git a/azure-pipelines.yml b/azure-pipelines.yml
new file mode 100644
index 000000000..19cce3eeb
--- /dev/null
+++ b/azure-pipelines.yml
@@ -0,0 +1,11 @@
+jobs:
+- job: macOS
+  pool:
+    vmImage: 'macos-10.13'
+  steps:
+  - script: |
+      gem install bundler
+      bundle install --retry=3 --jobs=4
+    displayName: 'bundle install'
+  - script: ruby -Ilib exe/rake
+    displayName: 'ruby -Ilib exe/rake'
diff --git a/bin/bundle b/bin/bundle
new file mode 100755
index 000000000..524dfd3f2
--- /dev/null
+++ b/bin/bundle
@@ -0,0 +1,105 @@
+#!/usr/bin/env ruby
+# frozen_string_literal: true
+
+#
+# This file was generated by Bundler.
+#
+# The application 'bundle' is installed as part of a gem, and
+# this file is here to facilitate running it.
+#
+
+require "rubygems"
+
+m = Module.new do
+    module_function
+
+  def invoked_as_script?
+    File.expand_path($0) == File.expand_path(__FILE__)
+  end
+
+  def env_var_version
+    ENV["BUNDLER_VERSION"]
+  end
+
+  def cli_arg_version
+    return unless invoked_as_script? # don't want to hijack other binstubs
+    return unless "update".start_with?(ARGV.first || " ") # must be running `bundle update`
+    bundler_version = nil
+    update_index = nil
+    ARGV.each_with_index do |a, i|
+      if update_index && update_index.succ == i && a =~ Gem::Version::ANCHORED_VERSION_PATTERN
+        bundler_version = a
+      end
+      next unless a =~ /\A--bundler(?:[= ](#{Gem::Version::VERSION_PATTERN}))?\z/
+      bundler_version = $1 || ">= 0.a"
+      update_index = i
+    end
+    bundler_version
+  end
+
+  def gemfile
+    gemfile = ENV["BUNDLE_GEMFILE"]
+    return gemfile if gemfile && !gemfile.empty?
+
+    File.expand_path("../../Gemfile", __FILE__)
+  end
+
+  def lockfile
+    lockfile =
+      case File.basename(gemfile)
+      when "gems.rb" then gemfile.sub(/\.rb$/, gemfile)
+      else "#{gemfile}.lock"
+      end
+    File.expand_path(lockfile)
+  end
+
+  def lockfile_version
+    return unless File.file?(lockfile)
+    lockfile_contents = File.read(lockfile)
+    return unless lockfile_contents =~ /\n\nBUNDLED WITH\n\s{2,}(#{Gem::Version::VERSION_PATTERN})\n/
+    Regexp.last_match(1)
+  end
+
+  def bundler_version
+    @bundler_version ||= begin
+      env_var_version || cli_arg_version ||
+        lockfile_version || "#{Gem::Requirement.default}.a"
+    end
+  end
+
+  def load_bundler!
+    ENV["BUNDLE_GEMFILE"] ||= gemfile
+
+    # must dup string for RG < 1.8 compatibility
+    activate_bundler(bundler_version.dup)
+  end
+
+  def activate_bundler(bundler_version)
+    if Gem::Version.correct?(bundler_version) && Gem::Version.new(bundler_version).release < Gem::Version.new("2.0")
+      bundler_version = "< 2"
+    end
+    gem_error = activation_error_handling do
+      gem "bundler", bundler_version
+    end
+    return if gem_error.nil?
+    require_error = activation_error_handling do
+      require "bundler/version"
+    end
+    return if require_error.nil? && Gem::Requirement.new(bundler_version).satisfied_by?(Gem::Version.new(Bundler::VERSION))
+    warn "Activating bundler (#{bundler_version}) failed:\n#{gem_error.message}\n\nTo install the version of bundler this project requires, run `gem install bundler -v '#{bundler_version}'`"
+    exit 42
+  end
+
+  def activation_error_handling
+    yield
+    nil
+  rescue StandardError, LoadError => e
+    e
+  end
+end
+
+m.load_bundler!
+
+if m.invoked_as_script?
+  load Gem.bin_path("bundler", "bundle")
+end
diff --git a/bin/rake b/bin/rake
new file mode 100755
index 000000000..9275675e8
--- /dev/null
+++ b/bin/rake
@@ -0,0 +1,29 @@
+#!/usr/bin/env ruby
+# frozen_string_literal: true
+
+#
+# This file was generated by Bundler.
+#
+# The application 'rake' is installed as part of a gem, and
+# this file is here to facilitate running it.
+#
+
+require "pathname"
+ENV["BUNDLE_GEMFILE"] ||= File.expand_path("../../Gemfile",
+  Pathname.new(__FILE__).realpath)
+
+bundle_binstub = File.expand_path("../bundle", __FILE__)
+
+if File.file?(bundle_binstub)
+  if File.read(bundle_binstub, 300) =~ /This file was generated by Bundler/
+    load(bundle_binstub)
+  else
+    abort("Your `bin/bundle` was not generated by Bundler, so this binstub cannot run.
+Replace `bin/bundle` by running `bundle binstubs bundler --force`, then run this command again.")
+  end
+end
+
+require "rubygems"
+require "bundler/setup"
+
+load Gem.bin_path("rake", "rake")
diff --git a/bin/rdoc b/bin/rdoc
new file mode 100755
index 000000000..a952e7988
--- /dev/null
+++ b/bin/rdoc
@@ -0,0 +1,29 @@
+#!/usr/bin/env ruby
+# frozen_string_literal: true
+
+#
+# This file was generated by Bundler.
+#
+# The application 'rdoc' is installed as part of a gem, and
+# this file is here to facilitate running it.
+#
+
+require "pathname"
+ENV["BUNDLE_GEMFILE"] ||= File.expand_path("../../Gemfile",
+  Pathname.new(__FILE__).realpath)
+
+bundle_binstub = File.expand_path("../bundle", __FILE__)
+
+if File.file?(bundle_binstub)
+  if File.read(bundle_binstub, 300) =~ /This file was generated by Bundler/
+    load(bundle_binstub)
+  else
+    abort("Your `bin/bundle` was not generated by Bundler, so this binstub cannot run.
+Replace `bin/bundle` by running `bundle binstubs bundler --force`, then run this command again.")
+  end
+end
+
+require "rubygems"
+require "bundler/setup"
+
+load Gem.bin_path("rdoc", "rdoc")
diff --git a/bin/rubocop b/bin/rubocop
new file mode 100755
index 000000000..d0c488293
--- /dev/null
+++ b/bin/rubocop
@@ -0,0 +1,29 @@
+#!/usr/bin/env ruby
+# frozen_string_literal: true
+
+#
+# This file was generated by Bundler.
+#
+# The application 'rubocop' is installed as part of a gem, and
+# this file is here to facilitate running it.
+#
+
+require "pathname"
+ENV["BUNDLE_GEMFILE"] ||= File.expand_path("../../Gemfile",
+  Pathname.new(__FILE__).realpath)
+
+bundle_binstub = File.expand_path("../bundle", __FILE__)
+
+if File.file?(bundle_binstub)
+  if File.read(bundle_binstub, 300) =~ /This file was generated by Bundler/
+    load(bundle_binstub)
+  else
+    abort("Your `bin/bundle` was not generated by Bundler, so this binstub cannot run.
+Replace `bin/bundle` by running `bundle binstubs bundler --force`, then run this command again.")
+  end
+end
+
+require "rubygems"
+require "bundler/setup"
+
+load Gem.bin_path("rubocop", "rubocop")
diff --git a/doc/jamis.rb b/doc/jamis.rb
index c7bc84ac5..531aa7573 100644
--- a/doc/jamis.rb
+++ b/doc/jamis.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module RDoc
 module Page
 
diff --git a/doc/rakefile.rdoc b/doc/rakefile.rdoc
index 89a28ebee..4014306a1 100644
--- a/doc/rakefile.rdoc
+++ b/doc/rakefile.rdoc
@@ -410,7 +410,7 @@ display a list of tasks that have a description.  If you use +desc+ to
 describe your major tasks, you have a semi-automatic way of generating
 a summary of your Rake file.
 
-  traken$ rake -T
+  $ rake -T
   (in /home/.../rake)
   rake clean            # Remove any temporary products.
   rake clobber          # Remove any generated file.
diff --git a/lib/rake.rb b/lib/rake.rb
index 07b03284b..0dfd05315 100644
--- a/lib/rake.rb
+++ b/lib/rake.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 #--
 # Copyright 2003-2010 by Jim Weirich (jim.weirich@gmail.com)
 #
diff --git a/lib/rake/application.rb b/lib/rake/application.rb
index e94f17290..9ac9b2130 100644
--- a/lib/rake/application.rb
+++ b/lib/rake/application.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "optparse"
 
 require "rake/task_manager"
@@ -61,6 +62,8 @@ def initialize
       add_loader("rake", DefaultLoader.new)
       @tty_output = STDOUT.tty?
       @terminal_columns = ENV["RAKE_COLUMNS"].to_i
+
+      set_default_options
     end
 
     # Run the Rake application.  The run method performs the following
@@ -73,19 +76,24 @@ def initialize
     # If you wish to build a custom rake command, you should call
     # +init+ on your application.  Then define any tasks.  Finally,
     # call +top_level+ to run your top level tasks.
-    def run
+    def run(argv = ARGV)
       standard_exception_handling do
-        init
+        init "rake", argv
         load_rakefile
         top_level
       end
     end
 
     # Initialize the command line parameters and app name.
-    def init(app_name="rake")
+    def init(app_name="rake", argv = ARGV)
       standard_exception_handling do
         @name = app_name
-        args = handle_options
+        begin
+          args = handle_options argv
+        rescue ArgumentError
+          # Backward compatibility for capistrano
+          args = handle_options
+        end
         collect_command_line_tasks(args)
       end
     end
@@ -164,7 +172,7 @@ def parse_task_string(string) # :nodoc:
       args = []
 
       begin
-        /((?:[^\\,]|\\.)*?)\s*(?:,\s*(.*))?$/ =~ remaining_args
+        /\s*((?:[^\\,]|\\.)*?)\s*(?:,\s*(.*))?$/ =~ remaining_args
 
         remaining_args = $2
         args << $1.gsub(/\\(.)/, '\1')
@@ -204,13 +212,22 @@ def display_error_message(ex) # :nodoc:
     end
 
     def display_exception_details(ex) # :nodoc:
-      seen = Thread.current[:rake_display_exception_details_seen] ||= []
-      return if seen.include? ex
-      seen << ex
+      display_exception_details_seen << ex
 
       display_exception_message_details(ex)
       display_exception_backtrace(ex)
-      display_exception_details(ex.cause) if has_cause?(ex)
+      display_cause_details(ex.cause) if has_cause?(ex)
+    end
+
+    def display_cause_details(ex) # :nodoc:
+      return if display_exception_details_seen.include? ex
+
+      trace "\nCaused by:"
+      display_exception_details(ex)
+    end
+
+    def display_exception_details_seen # :nodoc:
+      Thread.current[:rake_display_exception_details_seen] ||= []
     end
 
     def has_cause?(ex) # :nodoc:
@@ -375,7 +392,7 @@ def trace(*strings) # :nodoc:
 
     def sort_options(options) # :nodoc:
       options.sort_by { |opt|
-        opt.select { |o| o =~ /^-/ }.map(&:downcase).sort.reverse
+        opt.select { |o| o.is_a?(String) && o =~ /^-/ }.map(&:downcase).sort.reverse
       }
     end
     private :sort_options
@@ -617,9 +634,8 @@ def select_trace_output(options, trace_option, value) # :nodoc:
     # Read and handle the command line options.  Returns the command line
     # arguments that we didn't understand, which should (in theory) be just
     # task names and env vars.
-    def handle_options # :nodoc:
-      options.rakelib = ["rakelib"]
-      options.trace_output = $stderr
+    def handle_options(argv) # :nodoc:
+      set_default_options
 
       OptionParser.new do |opts|
         opts.banner = "#{Rake.application.name} [-f rakefile] {options} targets..."
@@ -633,7 +649,7 @@ def handle_options # :nodoc:
 
         standard_rake_options.each { |args| opts.on(*args) }
         opts.environment("RAKEOPT")
-      end.parse(ARGV)
+      end.parse(argv)
     end
 
     # Similar to the regular Ruby +require+ command, but will check
@@ -671,7 +687,7 @@ def print_rakefile_directory(location) # :nodoc:
 
     def raw_load_rakefile # :nodoc:
       rakefile, location = find_rakefile_location
-      if (! options.ignore_system) &&
+      if (!options.ignore_system) &&
           (options.load_system || rakefile.nil?) &&
           system_dir && File.directory?(system_dir)
         print_rakefile_directory(location)
@@ -781,5 +797,28 @@ def rakefile_location(backtrace=caller) # :nodoc:
       backtrace.find { |str| str =~ re } || ""
     end
 
+    def set_default_options # :nodoc:
+      options.always_multitask           = false
+      options.backtrace                  = false
+      options.build_all                  = false
+      options.dryrun                     = false
+      options.ignore_deprecate           = false
+      options.ignore_system              = false
+      options.job_stats                  = false
+      options.load_system                = false
+      options.nosearch                   = false
+      options.rakelib                    = %w[rakelib]
+      options.show_all_tasks             = false
+      options.show_prereqs               = false
+      options.show_task_pattern          = nil
+      options.show_tasks                 = nil
+      options.silent                     = false
+      options.suppress_backtrace_pattern = nil
+      options.thread_pool_size           = Rake.suggested_thread_count
+      options.trace                      = false
+      options.trace_output               = $stderr
+      options.trace_rules                = false
+    end
+
   end
 end
diff --git a/lib/rake/backtrace.rb b/lib/rake/backtrace.rb
index a89dd9f4d..31ff05450 100644
--- a/lib/rake/backtrace.rb
+++ b/lib/rake/backtrace.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Rake
   module Backtrace # :nodoc: all
     SYS_KEYS  = RbConfig::CONFIG.keys.grep(/(?:[a-z]prefix|libdir)\z/)
diff --git a/lib/rake/clean.rb b/lib/rake/clean.rb
index f66353a0a..5af44015e 100644
--- a/lib/rake/clean.rb
+++ b/lib/rake/clean.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 # The 'rake/clean' file defines two file lists (CLEAN and CLOBBER) and
 # two rake tasks (:clean and :clobber).
 #
diff --git a/lib/rake/cloneable.rb b/lib/rake/cloneable.rb
index d53645f2f..eddb77e2f 100644
--- a/lib/rake/cloneable.rb
+++ b/lib/rake/cloneable.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Rake
   ##
   # Mixin for creating easily cloned objects.
diff --git a/lib/rake/cpu_counter.rb b/lib/rake/cpu_counter.rb
index 82a5eb8aa..564a62859 100644
--- a/lib/rake/cpu_counter.rb
+++ b/lib/rake/cpu_counter.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Rake
 
   # Based on a script at:
@@ -31,7 +32,7 @@ def count
     require 'rbconfig'
 
     def count
-      if defined?(Java::Java)
+      if RUBY_PLATFORM == 'java'
         count_via_java_runtime
       else
         case RbConfig::CONFIG['host_os']
diff --git a/lib/rake/default_loader.rb b/lib/rake/default_loader.rb
index 6154408f4..d3b4650d3 100644
--- a/lib/rake/default_loader.rb
+++ b/lib/rake/default_loader.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Rake
 
   # Default Rakefile loader used by +import+.
diff --git a/lib/rake/dsl_definition.rb b/lib/rake/dsl_definition.rb
index c52bd601f..c80464020 100644
--- a/lib/rake/dsl_definition.rb
+++ b/lib/rake/dsl_definition.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 # Rake DSL functions.
 require "rake/file_utils_ext"
 
@@ -25,9 +26,9 @@ module DSL
     private
 
     # :call-seq:
-    #   task task_name
-    #   task task_name: dependencies
-    #   task task_name, arguments => dependencies
+    #   task(task_name)
+    #   task(task_name: dependencies)
+    #   task(task_name, arguments => dependencies)
     #
     # Declare a basic task.  The +task_name+ is always the first argument.  If
     # the task name contains a ":" it is defined in that namespace.
diff --git a/lib/rake/early_time.rb b/lib/rake/early_time.rb
index abcb1872b..80cc6bfad 100644
--- a/lib/rake/early_time.rb
+++ b/lib/rake/early_time.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Rake
 
   # EarlyTime is a fake timestamp that occurs _before_ any other time value.
diff --git a/lib/rake/ext/core.rb b/lib/rake/ext/core.rb
index 7575df15a..226f2125b 100644
--- a/lib/rake/ext/core.rb
+++ b/lib/rake/ext/core.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 class Module
   # Check for an existing method in the current class before extending.  If
   # the method already exists, then a warning is printed and the extension is
diff --git a/lib/rake/ext/string.rb b/lib/rake/ext/string.rb
index 37764c845..c70236ae9 100644
--- a/lib/rake/ext/string.rb
+++ b/lib/rake/ext/string.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "rake/ext/core"
 
 class String
@@ -136,7 +137,7 @@ def pathmap_replace(patterns, &block)
     # This String extension comes from Rake
     def pathmap(spec=nil, &block)
       return self if spec.nil?
-      result = ""
+      result = "".dup
       spec.scan(/%\{[^}]*\}-?\d*[sdpfnxX%]|%-?\d+d|%.|[^%]+/) do |frag|
         case frag
         when "%f"
diff --git a/lib/rake/file_creation_task.rb b/lib/rake/file_creation_task.rb
index f3c5c78a1..5a4c68492 100644
--- a/lib/rake/file_creation_task.rb
+++ b/lib/rake/file_creation_task.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "rake/file_task"
 require "rake/early_time"
 
@@ -11,7 +12,7 @@ module Rake
   class FileCreationTask < FileTask
     # Is this file task needed?  Yes if it doesn't exist.
     def needed?
-      ! File.exist?(name)
+      !File.exist?(name)
     end
 
     # Time stamp for file creation task.  This time stamp is earlier
diff --git a/lib/rake/file_list.rb b/lib/rake/file_list.rb
index a30c6338c..22c339f24 100644
--- a/lib/rake/file_list.rb
+++ b/lib/rake/file_list.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "rake/cloneable"
 require "rake/file_utils_ext"
 require "rake/ext/string"
@@ -293,7 +294,7 @@ def egrep(pattern, *options)
       matched = 0
       each do |fn|
         begin
-          open(fn, "r", *options) do |inf|
+          File.open(fn, "r", *options) do |inf|
             count = 0
             inf.each do |line|
               count += 1
@@ -317,14 +318,14 @@ def egrep(pattern, *options)
     # Return a new file list that only contains file names from the current
     # file list that exist on the file system.
     def existing
-      select { |fn| File.exist?(fn) }
+      select { |fn| File.exist?(fn) }.uniq
     end
 
     # Modify the current file list so that it contains only file name that
     # exist on the file system.
     def existing!
       resolve
-      @items = @items.select { |fn| File.exist?(fn) }
+      @items = @items.select { |fn| File.exist?(fn) }.uniq
       self
     end
 
@@ -384,7 +385,7 @@ def excluded_from_list?(fn)
       /~$/
     ]
     DEFAULT_IGNORE_PROCS = [
-      proc { |fn| fn =~ /(^|[\/\\])core$/ && ! File.directory?(fn) }
+      proc { |fn| fn =~ /(^|[\/\\])core$/ && !File.directory?(fn) }
     ]
 
     def import(array) # :nodoc:
diff --git a/lib/rake/file_task.rb b/lib/rake/file_task.rb
index 6656e7095..db790e39f 100644
--- a/lib/rake/file_task.rb
+++ b/lib/rake/file_task.rb
@@ -1,4 +1,5 @@
-require "rake/task.rb"
+# frozen_string_literal: true
+require "rake/task"
 require "rake/early_time"
 
 module Rake
@@ -13,7 +14,7 @@ class FileTask < Task
     # Is this file task needed?  Yes if it doesn't exist, or if its time stamp
     # is out of date.
     def needed?
-      ! File.exist?(name) || out_of_date?(timestamp) || @application.options.build_all
+      !File.exist?(name) || out_of_date?(timestamp) || @application.options.build_all
     end
 
     # Time stamp for file task.
@@ -29,7 +30,14 @@ def timestamp
 
     # Are there any prerequisites with a later time than the given time stamp?
     def out_of_date?(stamp)
-      @prerequisites.any? { |n| application[n, @scope].timestamp > stamp }
+      all_prerequisite_tasks.any? { |prereq|
+        prereq_task = application[prereq, @scope]
+        if prereq_task.instance_of?(Rake::FileTask)
+          prereq_task.timestamp > stamp || @application.options.build_all
+        else
+          prereq_task.timestamp > stamp
+        end
+      }
     end
 
     # ----------------------------------------------------------------
diff --git a/lib/rake/file_utils.rb b/lib/rake/file_utils.rb
index aa065e8b4..dc434c8d9 100644
--- a/lib/rake/file_utils.rb
+++ b/lib/rake/file_utils.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "rbconfig"
 require "fileutils"
 
@@ -34,7 +35,7 @@ module FileUtils
   #
   #   # check exit status after command runs
   #   sh %{grep pattern file} do |ok, res|
-  #     if ! ok
+  #     if !ok
   #       puts "pattern not found (status = #{res.exitstatus})"
   #     end
   #   end
@@ -50,7 +51,7 @@ def sh(*cmd, &block)
     Rake.rake_output_message sh_show_command cmd if verbose
 
     unless noop
-      res = system(*cmd, options)
+      res = (Hash === cmd.last) ? system(*cmd) : system(*cmd, options)
       status = $?
       status = Rake::PseudoStatus.new(1) if !res && status.nil?
       shell_runner.call(res, status)
@@ -110,7 +111,7 @@ def ruby(*args, &block)
   #  Attempt to do a normal file link, but fall back to a copy if the link
   #  fails.
   def safe_ln(*args)
-    if ! LN_SUPPORTED[0]
+    if !LN_SUPPORTED[0]
       cp(*args)
     else
       begin
diff --git a/lib/rake/file_utils_ext.rb b/lib/rake/file_utils_ext.rb
index e5930d4ab..bf558b749 100644
--- a/lib/rake/file_utils_ext.rb
+++ b/lib/rake/file_utils_ext.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "rake/file_utils"
 
 module Rake
diff --git a/lib/rake/invocation_chain.rb b/lib/rake/invocation_chain.rb
index 540628957..44a995496 100644
--- a/lib/rake/invocation_chain.rb
+++ b/lib/rake/invocation_chain.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Rake
 
   # InvocationChain tracks the chain of task invocations to detect
diff --git a/lib/rake/invocation_exception_mixin.rb b/lib/rake/invocation_exception_mixin.rb
index 84ff3353b..b0d307a48 100644
--- a/lib/rake/invocation_exception_mixin.rb
+++ b/lib/rake/invocation_exception_mixin.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Rake
   module InvocationExceptionMixin
     # Return the invocation chain (list of Rake tasks) that were in
diff --git a/lib/rake/late_time.rb b/lib/rake/late_time.rb
index d1d9470ec..8fe024943 100644
--- a/lib/rake/late_time.rb
+++ b/lib/rake/late_time.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Rake
   # LateTime is a fake timestamp that occurs _after_ any other time value.
   class LateTime
diff --git a/lib/rake/linked_list.rb b/lib/rake/linked_list.rb
index 54d0c1287..11fa46f0d 100644
--- a/lib/rake/linked_list.rb
+++ b/lib/rake/linked_list.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Rake
 
   # Polylithic linked list structure used to implement several data
diff --git a/lib/rake/loaders/makefile.rb b/lib/rake/loaders/makefile.rb
index d0436bb79..46f4beaad 100644
--- a/lib/rake/loaders/makefile.rb
+++ b/lib/rake/loaders/makefile.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Rake
 
   # Makefile loader to be used with the import file loader.  Use this to
diff --git a/lib/rake/multi_task.rb b/lib/rake/multi_task.rb
index 7118dc411..3ae363cbe 100644
--- a/lib/rake/multi_task.rb
+++ b/lib/rake/multi_task.rb
@@ -1,49 +1,14 @@
+# frozen_string_literal: true
 module Rake
 
   # Same as a regular task, but the immediate prerequisites are done in
   # parallel using Ruby threads.
   #
   class MultiTask < Task
-
-    # Same as invoke, but explicitly pass a call chain to detect
-    # circular dependencies. This is largely copied from Rake::Task
-    # but has been updated such that if multiple tasks depend on this
-    # one in parallel, they will all fail if the first execution of
-    # this task fails.
-    def invoke_with_call_chain(task_args, invocation_chain)
-      new_chain = Rake::InvocationChain.append(self, invocation_chain)
-      @lock.synchronize do
-        begin
-          if @already_invoked
-            if @invocation_exception
-              if application.options.trace
-                application.trace "** Previous invocation of #{name} failed #{format_trace_flags}"
-              end
-              raise @invocation_exception
-            else
-              return
-            end
-          end
-
-          if application.options.trace
-            application.trace "** Invoke #{name} #{format_trace_flags}"
-          end
-          @already_invoked = true
-
-          invoke_prerequisites(task_args, new_chain)
-          execute(task_args) if needed?
-        rescue Exception => ex
-          add_chain_to(ex, new_chain)
-          @invocation_exception = ex
-          raise
-        end
-      end
-    end
-
     private
+
     def invoke_prerequisites(task_args, invocation_chain) # :nodoc:
       invoke_prerequisites_concurrently(task_args, invocation_chain)
     end
   end
-
 end
diff --git a/lib/rake/name_space.rb b/lib/rake/name_space.rb
index 0d7eb80b6..32f8139fc 100644
--- a/lib/rake/name_space.rb
+++ b/lib/rake/name_space.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 ##
 # The NameSpace class will lookup task names in the scope defined by a
 # +namespace+ command.
diff --git a/lib/rake/packagetask.rb b/lib/rake/packagetask.rb
index 034b8e9e8..72fef4d5e 100644
--- a/lib/rake/packagetask.rb
+++ b/lib/rake/packagetask.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 # Define a package task library to aid in the definition of
 # redistributable package files.
 
@@ -131,9 +132,7 @@ def define
           task package: ["#{package_dir}/#{file}"]
           file "#{package_dir}/#{file}" =>
             [package_dir_path] + package_files do
-            chdir(package_dir) do
-              sh @tar_command, "#{flag}cvf", file, package_name
-            end
+            chdir(package_dir) { sh @tar_command, "#{flag}cvf", file, package_name }
           end
         end
       end
@@ -142,9 +141,7 @@ def define
         task package: ["#{package_dir}/#{zip_file}"]
         file "#{package_dir}/#{zip_file}" =>
           [package_dir_path] + package_files do
-          chdir(package_dir) do
-            sh @zip_command, "-r", zip_file, package_name
-          end
+          chdir(package_dir) { sh @zip_command, "-r", zip_file, package_name }
         end
       end
 
diff --git a/lib/rake/phony.rb b/lib/rake/phony.rb
index a172f9c60..8caa5de17 100644
--- a/lib/rake/phony.rb
+++ b/lib/rake/phony.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 # Defines a :phony task that you can use as a dependency. This allows
 # file-based tasks to use non-file-based tasks as prerequisites
 # without forcing them to rebuild.
diff --git a/lib/rake/private_reader.rb b/lib/rake/private_reader.rb
index 162097857..2815ce643 100644
--- a/lib/rake/private_reader.rb
+++ b/lib/rake/private_reader.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Rake
 
   # Include PrivateReader to use +private_reader+.
diff --git a/lib/rake/promise.rb b/lib/rake/promise.rb
index 37221e427..f45af4f3a 100644
--- a/lib/rake/promise.rb
+++ b/lib/rake/promise.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Rake
 
   # A Promise object represents a promise to do work (a chore) in the
@@ -70,12 +71,12 @@ def chore
 
     # Do we have a result for the promise
     def result?
-      ! @result.equal?(NOT_SET)
+      !@result.equal?(NOT_SET)
     end
 
     # Did the promise throw an error
     def error?
-      ! @error.equal?(NOT_SET)
+      !@error.equal?(NOT_SET)
     end
 
     # Are we done with the promise
diff --git a/lib/rake/pseudo_status.rb b/lib/rake/pseudo_status.rb
index 16e1903bd..8b3c98949 100644
--- a/lib/rake/pseudo_status.rb
+++ b/lib/rake/pseudo_status.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Rake
 
   ##
diff --git a/lib/rake/rake_module.rb b/lib/rake/rake_module.rb
index 75feb1261..03c295624 100644
--- a/lib/rake/rake_module.rb
+++ b/lib/rake/rake_module.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "rake/application"
 
 module Rake
@@ -33,6 +34,34 @@ def add_rakelib(*files)
       application.options.rakelib ||= []
       application.options.rakelib.concat(files)
     end
+
+    # Make +block_application+ the default rake application inside a block so
+    # you can load rakefiles into a different application.
+    #
+    # This is useful when you want to run rake tasks inside a library without
+    # running rake in a sub-shell.
+    #
+    # Example:
+    #
+    #   Dir.chdir 'other/directory'
+    #
+    #   other_rake = Rake.with_application do |rake|
+    #     rake.load_rakefile
+    #   end
+    #
+    #   puts other_rake.tasks
+
+    def with_application(block_application = Rake::Application.new)
+      orig_application = Rake.application
+
+      Rake.application = block_application
+
+      yield block_application
+
+      block_application
+    ensure
+      Rake.application = orig_application
+    end
   end
 
 end
diff --git a/lib/rake/rake_test_loader.rb b/lib/rake/rake_test_loader.rb
index d299efe35..f0f7772ba 100644
--- a/lib/rake/rake_test_loader.rb
+++ b/lib/rake/rake_test_loader.rb
@@ -1,20 +1,26 @@
+# frozen_string_literal: true
 require "rake"
 
 # Load the test files from the command line.
 argv = ARGV.select do |argument|
-  case argument
-  when /^-/ then
-    argument
-  when /\*/ then
-    FileList[argument].to_a.each do |file|
-      require File.expand_path file
-    end
+  begin
+    case argument
+    when /^-/ then
+      argument
+    when /\*/ then
+      FileList[argument].to_a.each do |file|
+        require File.expand_path file
+      end
 
-    false
-  else
-    require File.expand_path argument
+      false
+    else
+      require File.expand_path argument
 
-    false
+      false
+    end
+  rescue LoadError => e
+    raise unless e.path
+    abort "\nFile does not exist: #{e.path}\n\n"
   end
 end
 
diff --git a/lib/rake/rule_recursion_overflow_error.rb b/lib/rake/rule_recursion_overflow_error.rb
index 39d44aac6..a51e77489 100644
--- a/lib/rake/rule_recursion_overflow_error.rb
+++ b/lib/rake/rule_recursion_overflow_error.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Rake
 
   # Error indicating a recursion overflow error in task selection.
diff --git a/lib/rake/scope.rb b/lib/rake/scope.rb
index b432f5f29..fc1eb6c3a 100644
--- a/lib/rake/scope.rb
+++ b/lib/rake/scope.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Rake
   class Scope < LinkedList # :nodoc: all
 
@@ -15,7 +16,7 @@ def path_with_task_name(task_name)
     # this trim beyond the toplevel scope.
     def trim(n)
       result = self
-      while n > 0 && ! result.empty?
+      while n > 0 && !result.empty?
         result = result.tail
         n -= 1
       end
diff --git a/lib/rake/task.rb b/lib/rake/task.rb
index 23faf96e5..10c563c92 100644
--- a/lib/rake/task.rb
+++ b/lib/rake/task.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "rake/invocation_exception_mixin"
 
 module Rake
@@ -14,6 +15,7 @@ module Rake
   class Task
     # List of prerequisites for a task.
     attr_reader :prerequisites
+    alias prereqs prerequisites
 
     # List of actions attached to a task.
     attr_reader :actions
@@ -102,6 +104,7 @@ def initialize(task_name, app)
       @scope           = app.current_scope
       @arg_names       = nil
       @locations       = []
+      @invocation_exception = nil
     end
 
     # Enhance a task with prerequisites or actions.  Returns self.
@@ -182,20 +185,39 @@ def invoke(*args)
 
     # Same as invoke, but explicitly pass a call chain to detect
     # circular dependencies.
-    def invoke_with_call_chain(task_args, invocation_chain) # :nodoc:
-      new_chain = InvocationChain.append(self, invocation_chain)
+    #
+    # If multiple tasks depend on this
+    # one in parallel, they will all fail if the first execution of
+    # this task fails.
+    def invoke_with_call_chain(task_args, invocation_chain)
+      new_chain = Rake::InvocationChain.append(self, invocation_chain)
       @lock.synchronize do
-        if application.options.trace
-          application.trace "** Invoke #{name} #{format_trace_flags}"
+        begin
+          if application.options.trace
+            application.trace "** Invoke #{name} #{format_trace_flags}"
+          end
+
+          if @already_invoked
+            if @invocation_exception
+              if application.options.trace
+                application.trace "** Previous invocation of #{name} failed #{format_trace_flags}"
+              end
+              raise @invocation_exception
+            else
+              return
+            end
+          end
+
+          @already_invoked = true
+
+          invoke_prerequisites(task_args, new_chain)
+          execute(task_args) if needed?
+        rescue Exception => ex
+          add_chain_to(ex, new_chain)
+          @invocation_exception = ex
+          raise ex
         end
-        return if @already_invoked
-        @already_invoked = true
-        invoke_prerequisites(task_args, new_chain)
-        execute(task_args) if needed?
       end
-    rescue Exception => ex
-      add_chain_to(ex, new_chain)
-      raise ex
     end
     protected :invoke_with_call_chain
 
@@ -226,7 +248,8 @@ def invoke_prerequisites_concurrently(task_args, invocation_chain)# :nodoc:
           r.invoke_with_call_chain(prereq_args, invocation_chain)
         end
       end
-      futures.each(&:value)
+      # Iterate in reverse to improve performance related to thread waiting and switching
+      futures.reverse_each(&:value)
     end
 
     # Format the trace flags for display.
@@ -266,7 +289,7 @@ def timestamp
     def add_description(description)
       return unless description
       comment = description.strip
-      add_comment(comment) if comment && ! comment.empty?
+      add_comment(comment) if comment && !comment.empty?
     end
 
     def comment=(comment) # :nodoc:
@@ -320,7 +343,7 @@ def set_arg_names(args)
     # Return a string describing the internal state of a task.  Useful for
     # debugging.
     def investigation
-      result = "------------------------------\n"
+      result = "------------------------------\n".dup
       result << "Investigating #{name}\n"
       result << "class: #{self.class}\n"
       result <<  "task needed: #{needed?}\n"
diff --git a/lib/rake/task_argument_error.rb b/lib/rake/task_argument_error.rb
index 3e1dda64d..ef20076c6 100644
--- a/lib/rake/task_argument_error.rb
+++ b/lib/rake/task_argument_error.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Rake
 
   # Error indicating an ill-formed task declaration.
diff --git a/lib/rake/task_arguments.rb b/lib/rake/task_arguments.rb
index c98057c8f..0d3001afd 100644
--- a/lib/rake/task_arguments.rb
+++ b/lib/rake/task_arguments.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Rake
 
   ##
diff --git a/lib/rake/task_manager.rb b/lib/rake/task_manager.rb
index b62edc8e3..1991088fa 100644
--- a/lib/rake/task_manager.rb
+++ b/lib/rake/task_manager.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Rake
 
   # The TaskManager module is a mixin for managing tasks.
@@ -55,7 +56,26 @@ def [](task_name, scopes=nil)
       self.lookup(task_name, scopes) or
         enhance_with_matching_rule(task_name) or
         synthesize_file_task(task_name) or
-        fail "Don't know how to build task '#{task_name}' (see --tasks)"
+        fail generate_message_for_undefined_task(task_name)
+    end
+
+    def generate_message_for_undefined_task(task_name)
+      message = "Don't know how to build task '#{task_name}' "\
+                "(See the list of available tasks with `#{Rake.application.name} --tasks`)"
+      message + generate_did_you_mean_suggestions(task_name)
+    end
+
+    def generate_did_you_mean_suggestions(task_name)
+      return "" unless defined?(::DidYouMean::SpellChecker)
+
+      suggestions = ::DidYouMean::SpellChecker.new(dictionary: @tasks.keys).correct(task_name.to_s)
+      if ::DidYouMean.respond_to?(:formatter)# did_you_mean v1.2.0 or later
+        ::DidYouMean.formatter.message_for(suggestions)
+      elsif defined?(::DidYouMean::Formatter) # before did_you_mean v1.2.0
+        ::DidYouMean::Formatter.new(suggestions).to_s
+      else
+        ""
+      end
     end
 
     def synthesize_file_task(task_name) # :nodoc:
@@ -126,8 +146,8 @@ def enhance_with_matching_rule(task_name, level=0)
       fail Rake::RuleRecursionOverflowError,
         "Rule Recursion Too Deep" if level >= 16
       @rules.each do |pattern, args, extensions, block|
-        if pattern.match(task_name)
-          task = attempt_rule(task_name, args, extensions, block, level)
+        if pattern && pattern.match(task_name)
+          task = attempt_rule(task_name, pattern, args, extensions, block, level)
           return task if task
         end
       end
@@ -241,8 +261,8 @@ def trace_rule(level, message) # :nodoc:
     end
 
     # Attempt to create a rule given the list of prerequisites.
-    def attempt_rule(task_name, args, extensions, block, level)
-      sources = make_sources(task_name, extensions)
+    def attempt_rule(task_name, task_pattern, args, extensions, block, level)
+      sources = make_sources(task_name, task_pattern, extensions)
       prereqs = sources.map { |source|
         trace_rule level, "Attempting Rule #{task_name} => #{source}"
         if File.exist?(source) || Rake::Task.task_defined?(source)
@@ -263,7 +283,7 @@ def attempt_rule(task_name, args, extensions, block, level)
 
     # Make a list of sources from the list of file name extensions /
     # translation procs.
-    def make_sources(task_name, extensions)
+    def make_sources(task_name, task_pattern, extensions)
       result = extensions.map { |ext|
         case ext
         when /%/
@@ -271,7 +291,8 @@ def make_sources(task_name, extensions)
         when %r{/}
           ext
         when /^\./
-          task_name.ext(ext)
+          source = task_name.sub(task_pattern, ext)
+          source == ext ? task_name.ext(ext) : source
         when String
           ext
         when Proc, Method
diff --git a/lib/rake/tasklib.rb b/lib/rake/tasklib.rb
index 7bcda1789..5354b4f94 100644
--- a/lib/rake/tasklib.rb
+++ b/lib/rake/tasklib.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "rake"
 
 module Rake
diff --git a/lib/rake/testtask.rb b/lib/rake/testtask.rb
index bb7f0ee8a..537627567 100644
--- a/lib/rake/testtask.rb
+++ b/lib/rake/testtask.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "rake"
 require "rake/tasklib"
 
@@ -50,6 +51,7 @@ class TestTask < TaskLib
 
     # Request that the tests be run with the warning flag set.
     # E.g. warning=true implies "ruby -w" used to run the tests.
+    # (default is true)
     attr_accessor :warning
 
     # Glob pattern to match test files. (default is 'test/test*.rb')
diff --git a/lib/rake/thread_history_display.rb b/lib/rake/thread_history_display.rb
index 04273541e..412ea37be 100644
--- a/lib/rake/thread_history_display.rb
+++ b/lib/rake/thread_history_display.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "rake/private_reader"
 
 module Rake
diff --git a/lib/rake/thread_pool.rb b/lib/rake/thread_pool.rb
index 1c2f5f50f..b01a5efe0 100644
--- a/lib/rake/thread_pool.rb
+++ b/lib/rake/thread_pool.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "set"
 
 require "rake/promise"
diff --git a/lib/rake/trace_output.rb b/lib/rake/trace_output.rb
index c740b9e23..d713a0926 100644
--- a/lib/rake/trace_output.rb
+++ b/lib/rake/trace_output.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module Rake
   module TraceOutput # :nodoc: all
 
diff --git a/lib/rake/version.rb b/lib/rake/version.rb
index 1908ff855..6014e9322 100644
--- a/lib/rake/version.rb
+++ b/lib/rake/version.rb
@@ -1,5 +1,6 @@
+# frozen_string_literal: true
 module Rake
-  VERSION = "12.0.0"
+  VERSION = "12.3.3"
 
   module Version # :nodoc: all
     MAJOR, MINOR, BUILD, *OTHER = Rake::VERSION.split "."
diff --git a/lib/rake/win32.rb b/lib/rake/win32.rb
index 1fc02a5ae..6e6203181 100644
--- a/lib/rake/win32.rb
+++ b/lib/rake/win32.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 require "rbconfig"
 
 module Rake
diff --git a/rake.gemspec b/rake.gemspec
index 8479b9314..66c567ca9 100644
--- a/rake.gemspec
+++ b/rake.gemspec
@@ -1,10 +1,10 @@
+# frozen_string_literal: true
 $LOAD_PATH.unshift File.expand_path('../lib', __FILE__)
 require 'rake/version'
 
 Gem::Specification.new do |s|
   s.name = "rake".freeze
   s.version = Rake::VERSION
-  s.date = "2016-12-06"
   s.authors = ["Hiroshi SHIBATA".freeze, "Eric Hodel".freeze, "Jim Weirich".freeze]
   s.email = ["hsbt@ruby-lang.org".freeze, "drbrain@segment7.net".freeze, "".freeze]
 
@@ -23,12 +23,13 @@ Rake has the following features:
   s.homepage = "https://github.com/ruby/rake".freeze
   s.licenses = ["MIT".freeze]
 
-  s.files = `git ls-files -z`.split("\x0").reject { |f| f.match(%r{^(test|spec|features)/}) }
+  s.files = %x[git ls-files -z].split("\x0").reject { |f| f.match(%r{^(test|spec|features)/}) } -
+            %w[.rubocop.yml .gitignore .travis.yml appveyor.yml]
   s.bindir = "exe"
   s.executables = s.files.grep(%r{^exe/}) { |f| File.basename(f) }
   s.require_paths = ["lib".freeze]
 
-  s.required_ruby_version = Gem::Requirement.new(">= 1.9.3".freeze)
+  s.required_ruby_version = Gem::Requirement.new(">= 2.0.0".freeze)
   s.rubygems_version = "2.6.1".freeze
   s.required_rubygems_version = Gem::Requirement.new(">= 1.3.2".freeze)
   s.rdoc_options = ["--main".freeze, "README.rdoc".freeze]
@@ -36,4 +37,6 @@ Rake has the following features:
   s.add_development_dependency(%q<bundler>.freeze)
   s.add_development_dependency(%q<minitest>.freeze)
   s.add_development_dependency(%q<rdoc>.freeze)
+  s.add_development_dependency(%q<coveralls>.freeze)
+  s.add_development_dependency(%q<rubocop>.freeze)
 end
diff --git a/test/helper.rb b/test/helper.rb
index 7736da72f..64f7db7e2 100644
--- a/test/helper.rb
+++ b/test/helper.rb
@@ -1,5 +1,15 @@
+# frozen_string_literal: true
 $:.unshift File.expand_path("../../lib", __FILE__)
 
+begin
+  if ENV["COVERALLS"]
+    gem "coveralls"
+    require "coveralls"
+    Coveralls.wear!
+  end
+rescue Gem::LoadError
+end
+
 gem "minitest", "~> 5"
 require "minitest/autorun"
 require "rake"
@@ -18,7 +28,7 @@ class TaskManager
     include Rake::TaskManager
   end
 
-  RUBY = Gem.ruby
+  RUBY = File.realpath(ENV["BUNDLE_RUBY"] || Gem.ruby)
 
   def setup
     ARGV.clear
diff --git a/test/support/file_creation.rb b/test/support/file_creation.rb
index facc57a03..a1313bc0e 100644
--- a/test/support/file_creation.rb
+++ b/test/support/file_creation.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module FileCreation
   OLDFILE = "old"
   NEWFILE = "new"
diff --git a/test/support/rakefile_definitions.rb b/test/support/rakefile_definitions.rb
index e0af05a67..5dacd3783 100644
--- a/test/support/rakefile_definitions.rb
+++ b/test/support/rakefile_definitions.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module RakefileDefinitions
   include FileUtils
 
@@ -77,6 +78,24 @@ def rakefile_chains
     DEFAULT
   end
 
+  def rakefile_file_chains
+    rakefile <<-RAKEFILE
+file "fileA" do |t|
+  sh "echo contentA >\#{t.name}"
+end
+
+file "fileB" => "fileA" do |t|
+  sh "(cat fileA; echo transformationB) >\#{t.name}"
+end
+
+file "fileC" => "fileB" do |t|
+  sh "(cat fileB; echo transformationC) >\#{t.name}"
+end
+
+task default: "fileC"
+    RAKEFILE
+  end
+
   def rakefile_comments
     rakefile <<-COMMENTS
 # comment for t1
diff --git a/test/support/ruby_runner.rb b/test/support/ruby_runner.rb
index 199f60dd6..160a57090 100644
--- a/test/support/ruby_runner.rb
+++ b/test/support/ruby_runner.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 module RubyRunner
   include FileUtils
 
diff --git a/test/test_private_reader.rb b/test/test_private_reader.rb
index 56160f062..ee22e1b40 100644
--- a/test/test_private_reader.rb
+++ b/test/test_private_reader.rb
@@ -1,9 +1,10 @@
+# frozen_string_literal: true
 require File.expand_path("../helper", __FILE__)
 require "rake/private_reader"
 
-class TestPrivateAttrs < Rake::TestCase
+class TestPrivateAttrs < Rake::TestCase # :nodoc:
 
-  class Sample
+  class Sample # :nodoc:
     include Rake::PrivateReader
 
     private_reader :reader, :a
diff --git a/test/test_rake.rb b/test/test_rake.rb
index dfbb7d232..a6d08fd35 100644
--- a/test/test_rake.rb
+++ b/test/test_rake.rb
@@ -1,6 +1,7 @@
+# frozen_string_literal: true
 require File.expand_path("../helper", __FILE__)
 
-class TestRake < Rake::TestCase
+class TestRake < Rake::TestCase # :nodoc:
   def test_each_dir_parent
     assert_equal ["a"], alldirs("a")
     assert_equal ["a/b", "a"], alldirs("a/b")
diff --git a/test/test_rake_application.rb b/test/test_rake_application.rb
index 62bb4c6ac..27645ea12 100644
--- a/test/test_rake_application.rb
+++ b/test/test_rake_application.rb
@@ -1,7 +1,7 @@
-#encoding: UTF-8
+# frozen_string_literal: true
 require File.expand_path("../helper", __FILE__)
 
-class TestRakeApplication < Rake::TestCase
+class TestRakeApplication < Rake::TestCase # :nodoc:
 
   def setup
     super
@@ -10,11 +10,34 @@ def setup
     @app.options.rakelib = []
   end
 
-  def setup_command_line(*options)
-    ARGV.clear
-    options.each do |option|
-      ARGV << option
+  def test_class_with_application
+    orig_app = Rake.application
+
+    return_app = Rake.with_application do |yield_app|
+      refute_equal orig_app, yield_app, "new application must be yielded"
+
+      assert_equal yield_app, Rake.application,
+                   "new application must be default in block"
     end
+
+    refute_equal orig_app, return_app, "new application not returned"
+    assert_equal orig_app, Rake.application, "original application not default"
+  end
+
+  def test_class_with_application_user_defined
+    orig_app = Rake.application
+
+    user_app = Rake::Application.new
+
+    return_app = Rake.with_application user_app do |yield_app|
+      assert_equal user_app, yield_app, "user application must be yielded"
+
+      assert_equal user_app, Rake.application,
+                   "user application must be default in block"
+    end
+
+    assert_equal user_app, return_app, "user application not returned"
+    assert_equal orig_app, Rake.application, "original application not default"
   end
 
   def test_display_exception_details
@@ -26,6 +49,8 @@ def test_display_exception_details
     end
 
     out, err = capture_io do
+      @app.set_default_options # reset trace output IO
+
       @app.display_error_message ex
     end
 
@@ -37,11 +62,13 @@ def test_display_exception_details
 
   def test_display_exception_details_bad_encoding
     begin
-      raise "El Niño is coming!".force_encoding("US-ASCII")
+      raise "El Niño is coming!".dup.force_encoding("US-ASCII")
     rescue => ex
     end
 
     out, err = capture_io do
+      @app.set_default_options # reset trace output IO
+
       @app.display_error_message ex
     end
 
@@ -63,39 +90,14 @@ def test_display_exception_details_cause
     end
 
     out, err = capture_io do
-      @app.display_error_message ex
-    end
-
-    assert_empty out
+      @app.set_default_options # reset trace output IO
 
-    assert_match "cause a", err
-    assert_match "cause b", err
-  end
-
-  def test_display_exception_details_cause_loop
-    skip "Exception#cause not implemented" unless
-      Exception.method_defined? :cause
-    skip if jruby9? # https://github.com/jruby/jruby/issues/3654
-
-    begin
-      begin
-        raise "cause a"
-      rescue => a
-        begin
-          raise "cause b"
-        rescue
-          raise a
-        end
-      end
-    rescue => ex
-    end
-
-    out, err = capture_io do
       @app.display_error_message ex
     end
 
     assert_empty out
 
+    assert_match "Caused by:", err
     assert_match "cause a", err
     assert_match "cause b", err
   end
@@ -215,7 +217,7 @@ def test_load_rakefile
     rakefile_unittest
 
     @app.instance_eval do
-      handle_options
+      handle_options []
       options.silent = true
       load_rakefile
     end
@@ -243,7 +245,7 @@ def test_load_rakefile_from_subdir
     Dir.chdir "subdir"
 
     @app.instance_eval do
-      handle_options
+      handle_options []
       options.silent = true
       load_rakefile
     end
@@ -274,7 +276,7 @@ def test_load_rakefile_doesnt_print_rakefile_directory_from_subdir_if_silent
 
     _, err = capture_io do
       @app.instance_eval do
-        handle_options
+        handle_options []
         options.silent = true
         raw_load_rakefile
       end
@@ -286,12 +288,11 @@ def test_load_rakefile_doesnt_print_rakefile_directory_from_subdir_if_silent
   def test_load_rakefile_not_found
     skip if jruby9?
 
-    ARGV.clear
     Dir.chdir @tempdir
     ENV["RAKE_SYSTEM"] = "not_exist"
 
     @app.instance_eval do
-      handle_options
+      handle_options []
       options.silent = true
     end
 
@@ -308,7 +309,7 @@ def test_load_from_system_rakefile
     rake_system_dir
 
     @app.instance_eval do
-      handle_options
+      handle_options []
       options.silent = true
       options.load_system = true
       options.rakelib = []
@@ -330,7 +331,7 @@ def @app.standard_system_dir
     ENV["RAKE_SYSTEM"] = nil
 
     @app.instance_eval do
-      handle_options
+      handle_options []
       options.silent = true
       options.load_system = true
       options.rakelib = []
@@ -390,28 +391,22 @@ def test_building_imported_files_on_demand
   def test_handle_options_should_not_strip_options_from_argv
     assert !@app.options.trace
 
-    valid_option = "--trace"
-    setup_command_line(valid_option)
+    argv = %w[--trace]
+    @app.handle_options argv
 
-    @app.handle_options
-
-    assert ARGV.include?(valid_option)
+    assert_includes argv, "--trace"
     assert @app.options.trace
   end
 
   def test_handle_options_trace_default_is_stderr
-    setup_command_line("--trace")
-
-    @app.handle_options
+    @app.handle_options %w[--trace]
 
     assert_equal STDERR, @app.options.trace_output
     assert @app.options.trace
   end
 
   def test_handle_options_trace_overrides_to_stdout
-    setup_command_line("--trace=stdout")
-
-    @app.handle_options
+    @app.handle_options %w[--trace=stdout]
 
     assert_equal STDOUT, @app.options.trace_output
     assert @app.options.trace
@@ -420,18 +415,16 @@ def test_handle_options_trace_overrides_to_stdout
   def test_handle_options_trace_does_not_eat_following_task_names
     assert !@app.options.trace
 
-    setup_command_line("--trace", "sometask")
+    argv = %w[--trace sometask]
+    @app.handle_options argv
 
-    @app.handle_options
-    assert ARGV.include?("sometask")
+    assert argv.include?("sometask")
     assert @app.options.trace
   end
 
   def test_good_run
     ran = false
 
-    ARGV << '--rakelib=""'
-
     @app.options.silent = true
 
     @app.instance_eval do
@@ -441,7 +434,7 @@ def test_good_run
     rakefile_default
 
     out, err = capture_io do
-      @app.run
+      @app.run %w[--rakelib=""]
     end
 
     assert ran
@@ -451,10 +444,9 @@ def test_good_run
 
   def test_display_task_run
     ran = false
-    setup_command_line("-f", "-s", "--tasks", '--rakelib=""')
     @app.last_description = "COMMENT"
     @app.define_task(Rake::Task, "default")
-    out, = capture_io { @app.run }
+    out, = capture_io { @app.run %w[-f -s --tasks --rakelib=""] }
     assert @app.options.show_tasks
     assert ! ran
     assert_match(/rake default/, out)
@@ -463,13 +455,12 @@ def test_display_task_run
 
   def test_display_prereqs
     ran = false
-    setup_command_line("-f", "-s", "--prereqs", '--rakelib=""')
     @app.last_description = "COMMENT"
     t = @app.define_task(Rake::Task, "default")
     t.enhance([:a, :b])
     @app.define_task(Rake::Task, "a")
     @app.define_task(Rake::Task, "b")
-    out, = capture_io { @app.run }
+    out, = capture_io { @app.run %w[-f -s --prereqs --rakelib=""] }
     assert @app.options.show_prereqs
     assert ! ran
     assert_match(/rake a$/, out)
@@ -479,37 +470,29 @@ def test_display_prereqs
 
   def test_bad_run
     @app.intern(Rake::Task, "default").enhance { fail }
-    setup_command_line("-f", "-s",  '--rakelib=""')
     _, err = capture_io {
-      assert_raises(SystemExit) { @app.run }
+      assert_raises(SystemExit) { @app.run %w[-f -s --rakelib=""] }
     }
     assert_match(/see full trace/i, err)
-  ensure
-    ARGV.clear
   end
 
   def test_bad_run_with_trace
     @app.intern(Rake::Task, "default").enhance { fail }
-    setup_command_line("-f", "-s", "-t")
     _, err = capture_io {
-      assert_raises(SystemExit) { @app.run }
+      @app.set_default_options
+      assert_raises(SystemExit) { @app.run %w[-f -s -t] }
     }
     refute_match(/see full trace/i, err)
-  ensure
-    ARGV.clear
   end
 
   def test_bad_run_with_backtrace
     @app.intern(Rake::Task, "default").enhance { fail }
-    setup_command_line("-f", "-s", "--backtrace")
     _, err = capture_io {
       assert_raises(SystemExit) {
-        @app.run
+        @app.run %w[-f -s --backtrace]
       }
     }
     refute_match(/see full trace/, err)
-  ensure
-    ARGV.clear
   end
 
   CustomError = Class.new(RuntimeError)
@@ -518,10 +501,9 @@ def test_bad_run_includes_exception_name
     @app.intern(Rake::Task, "default").enhance {
       raise CustomError, "intentional"
     }
-    setup_command_line("-f", "-s")
     _, err = capture_io {
       assert_raises(SystemExit) {
-        @app.run
+        @app.run %w[-f -s]
       }
     }
     assert_match(/CustomError: intentional/, err)
@@ -531,10 +513,9 @@ def test_rake_error_excludes_exception_name
     @app.intern(Rake::Task, "default").enhance {
       fail "intentional"
     }
-    setup_command_line("-f", "-s")
     _, err = capture_io {
       assert_raises(SystemExit) {
-        @app.run
+        @app.run %w[-f -s]
       }
     }
    refute_match(/RuntimeError/, err)
@@ -555,28 +536,22 @@ def test_printing_original_exception_cause
         raise custom_error, "Secondary Error"
       end
     }
-    setup_command_line("-f", "-s")
     _ ,err = capture_io {
       assert_raises(SystemExit) {
-        @app.run
+        @app.run %w[-f -s]
       }
     }
     if cause_supported?
       assert_match(/Original Error/, err)
     end
     assert_match(/Secondary Error/, err)
-  ensure
-    ARGV.clear
   end
 
   def test_run_with_bad_options
     @app.intern(Rake::Task, "default").enhance { fail }
-    setup_command_line("-f", "-s", "--xyzzy")
     assert_raises(SystemExit) {
-      capture_io { @app.run }
+      capture_io { @app.run %w[-f -s --xyzzy] }
     }
-  ensure
-    ARGV.clear
   end
 
   def test_standard_exception_handling_invalid_option
@@ -596,6 +571,8 @@ def test_standard_exception_handling_invalid_option
 
   def test_standard_exception_handling_other
     out, err = capture_io do
+      @app.set_default_options # reset trace output IO
+
       e = assert_raises SystemExit do
         @app.standard_exception_handling do
           raise "blah"
diff --git a/test/test_rake_application_options.rb b/test/test_rake_application_options.rb
index 149d8dcfd..0ca06e264 100644
--- a/test/test_rake_application_options.rb
+++ b/test/test_rake_application_options.rb
@@ -1,14 +1,14 @@
+# frozen_string_literal: true
 require File.expand_path("../helper", __FILE__)
 
 TESTING_REQUIRE = []
 
-class TestRakeApplicationOptions < Rake::TestCase
+class TestRakeApplicationOptions < Rake::TestCase # :nodoc:
 
   def setup
     super
 
     @testkey = ENV["TESTKEY"]
-    clear_argv
     Rake::FileUtilsExt.verbose_flag = false
     Rake::FileUtilsExt.nowrite_flag = false
     TESTING_REQUIRE.clear
@@ -16,32 +16,27 @@ def setup
 
   def teardown
     ENV["TESTKEY"] = @testkey
-    clear_argv
     Rake::FileUtilsExt.verbose_flag = false
     Rake::FileUtilsExt.nowrite_flag = false
 
     super
   end
 
-  def clear_argv
-    ARGV.pop until ARGV.empty?
-  end
-
   def test_default_options
     opts = command_line
-    assert_nil opts.backtrace
-    assert_nil opts.dryrun
-    assert_nil opts.ignore_system
-    assert_nil opts.load_system
-    assert_nil opts.always_multitask
-    assert_nil opts.nosearch
+    assert_equal false, opts.backtrace
+    assert_equal false, opts.dryrun
+    assert_equal false, opts.ignore_system
+    assert_equal false, opts.load_system
+    assert_equal false, opts.always_multitask
+    assert_equal false, opts.nosearch
     assert_equal ["rakelib"], opts.rakelib
-    assert_nil opts.show_prereqs
+    assert_equal false, opts.show_prereqs
     assert_nil opts.show_task_pattern
     assert_nil opts.show_tasks
-    assert_nil opts.silent
-    assert_nil opts.trace
-    assert_nil opts.thread_pool_size
+    assert_equal false, opts.silent
+    assert_equal false, opts.trace
+    assert_equal Rake.suggested_thread_count, opts.thread_pool_size
     assert_equal ["rakelib"], opts.rakelib
     assert ! Rake::FileUtilsExt.verbose_flag
     assert ! Rake::FileUtilsExt.nowrite_flag
@@ -114,7 +109,7 @@ def test_help
 
   def test_jobs
     flags([]) do |opts|
-      assert_nil opts.thread_pool_size
+      assert_equal Rake.suggested_thread_count, opts.thread_pool_size
     end
     flags(["--jobs", "0"], ["-j", "0"]) do |opts|
       assert_equal 0, opts.thread_pool_size
@@ -328,12 +323,12 @@ def test_tasks
     flags("--tasks", "-T") do |opts|
       assert_equal :tasks, opts.show_tasks
       assert_equal(//.to_s, opts.show_task_pattern.to_s)
-      assert_nil opts.show_all_tasks
+      assert_equal false, opts.show_all_tasks
     end
     flags(["--tasks", "xyz"], ["-Txyz"]) do |opts|
       assert_equal :tasks, opts.show_tasks
       assert_equal(/xyz/.to_s, opts.show_task_pattern.to_s)
-      assert_nil opts.show_all_tasks
+      assert_equal false, opts.show_all_tasks
     end
     flags(["--tasks", "xyz", "--comments"]) do |opts|
       assert_equal :tasks, opts.show_tasks
@@ -444,8 +439,6 @@ def test_rake_explicit_task_library
 
   def flags(*sets)
     sets.each do |set|
-      ARGV.clear
-
       @exit = catch(:system_exit) { command_line(*set) }
 
       yield(@app.options) if block_given?
@@ -453,13 +446,12 @@ def flags(*sets)
   end
 
   def command_line(*options)
-    options.each do |opt| ARGV << opt end
     @app = Rake::Application.new
     def @app.exit(*args)
       throw :system_exit, :exit
     end
     @app.instance_eval do
-      args = handle_options
+      args = handle_options options
       collect_command_line_tasks(args)
     end
     @tasks = @app.top_level_tasks
diff --git a/test/test_rake_backtrace.rb b/test/test_rake_backtrace.rb
index ec727a292..27e3cecb7 100644
--- a/test/test_rake_backtrace.rb
+++ b/test/test_rake_backtrace.rb
@@ -1,7 +1,8 @@
+# frozen_string_literal: true
 require File.expand_path("../helper", __FILE__)
 require "open3"
 
-class TestBacktraceSuppression < Rake::TestCase
+class TestBacktraceSuppression < Rake::TestCase # :nodoc:
   def test_bin_rake_suppressed
     paths = ["something/bin/rake:12"]
 
@@ -35,7 +36,7 @@ def test_near_system_dir_isnt_suppressed
   end
 end
 
-class TestRakeBacktrace < Rake::TestCase
+class TestRakeBacktrace < Rake::TestCase # :nodoc:
   include RubyRunner
 
   def setup
diff --git a/test/test_rake_clean.rb b/test/test_rake_clean.rb
index 5439a415f..b0b1ad602 100644
--- a/test/test_rake_clean.rb
+++ b/test/test_rake_clean.rb
@@ -1,7 +1,8 @@
+# frozen_string_literal: true
 require File.expand_path("../helper", __FILE__)
 require "rake/clean"
 
-class TestRakeClean < Rake::TestCase
+class TestRakeClean < Rake::TestCase # :nodoc:
   def test_clean
     load "rake/clean.rb", true
 
diff --git a/test/test_rake_cpu_counter.rb b/test/test_rake_cpu_counter.rb
index aac16b2d7..5d04e7c97 100644
--- a/test/test_rake_cpu_counter.rb
+++ b/test/test_rake_cpu_counter.rb
@@ -1,6 +1,7 @@
+# frozen_string_literal: true
 require File.expand_path("../helper", __FILE__)
 
-class TestRakeCpuCounter < Rake::TestCase
+class TestRakeCpuCounter < Rake::TestCase # :nodoc:
 
   def setup
     super
@@ -27,7 +28,7 @@ def @cpu_counter.count; raise; end
     assert_equal(4, @cpu_counter.count_with_default)
   end
 
-  class TestClassMethod < Rake::TestCase
+  class TestClassMethod < Rake::TestCase  # :nodoc:
     def setup
       super
 
diff --git a/test/test_rake_definitions.rb b/test/test_rake_definitions.rb
index 464cc6309..52e468e3b 100644
--- a/test/test_rake_definitions.rb
+++ b/test/test_rake_definitions.rb
@@ -1,7 +1,8 @@
+# frozen_string_literal: true
 require File.expand_path("../helper", __FILE__)
 require "fileutils"
 
-class TestRakeDefinitions < Rake::TestCase
+class TestRakeDefinitions < Rake::TestCase # :nodoc:
   include Rake
 
   EXISTINGFILE = "existing"
diff --git a/test/test_rake_directory_task.rb b/test/test_rake_directory_task.rb
index e42bd9c77..5635afd13 100644
--- a/test/test_rake_directory_task.rb
+++ b/test/test_rake_directory_task.rb
@@ -1,8 +1,9 @@
+# frozen_string_literal: true
 require File.expand_path("../helper", __FILE__)
 require "fileutils"
 require "pathname"
 
-class TestRakeDirectoryTask < Rake::TestCase
+class TestRakeDirectoryTask < Rake::TestCase # :nodoc:
   include Rake
 
   def test_directory
diff --git a/test/test_rake_dsl.rb b/test/test_rake_dsl.rb
index 7f82c6afa..6d0e7344d 100644
--- a/test/test_rake_dsl.rb
+++ b/test/test_rake_dsl.rb
@@ -1,6 +1,7 @@
+# frozen_string_literal: true
 require File.expand_path("../helper", __FILE__)
 
-class TestRakeDsl < Rake::TestCase
+class TestRakeDsl < Rake::TestCase # :nodoc:
 
   def setup
     super
diff --git a/test/test_rake_early_time.rb b/test/test_rake_early_time.rb
index 71ee3e157..95040f67a 100644
--- a/test/test_rake_early_time.rb
+++ b/test/test_rake_early_time.rb
@@ -1,6 +1,7 @@
+# frozen_string_literal: true
 require File.expand_path("../helper", __FILE__)
 
-class TestRakeEarlyTime < Rake::TestCase
+class TestRakeEarlyTime < Rake::TestCase # :nodoc:
   def test_create
     early = Rake::EarlyTime.instance
     assert early <= Time.now
diff --git a/test/test_rake_extension.rb b/test/test_rake_extension.rb
index 293ec1304..aeb8ce148 100644
--- a/test/test_rake_extension.rb
+++ b/test/test_rake_extension.rb
@@ -1,9 +1,10 @@
+# frozen_string_literal: true
 require File.expand_path("../helper", __FILE__)
 require "stringio"
 
-class TestRakeExtension < Rake::TestCase
+class TestRakeExtension < Rake::TestCase # :nodoc:
 
-  module Redirect
+  module Redirect # :nodoc:
     def error_redirect
       old_err = $stderr
       result = StringIO.new
@@ -15,7 +16,7 @@ def error_redirect
     end
   end
 
-  class Sample
+  class Sample # :nodoc:
     extend Redirect
 
     def duplicate_method
diff --git a/test/test_rake_file_creation_task.rb b/test/test_rake_file_creation_task.rb
index 35f843e9e..05af13bb1 100644
--- a/test/test_rake_file_creation_task.rb
+++ b/test/test_rake_file_creation_task.rb
@@ -1,9 +1,9 @@
+# frozen_string_literal: true
 require File.expand_path("../helper", __FILE__)
 require "fileutils"
 
-class TestRakeFileCreationTask < Rake::TestCase
+class TestRakeFileCreationTask < Rake::TestCase # :nodoc:
   include Rake
-  include Rake::DSL
 
   DUMMY_DIR = "dummy_dir"
 
diff --git a/test/test_rake_file_list.rb b/test/test_rake_file_list.rb
index 32ca7a8e3..97ab99828 100644
--- a/test/test_rake_file_list.rb
+++ b/test/test_rake_file_list.rb
@@ -1,8 +1,9 @@
+# frozen_string_literal: true
 require File.expand_path("../helper", __FILE__)
 require "pathname"
 
-class TestRakeFileList < Rake::TestCase
-  FileList = Rake::FileList
+class TestRakeFileList < Rake::TestCase # :nodoc:
+  FileList = Rake::FileList # :nodoc:
 
   def setup
     super
@@ -414,13 +415,13 @@ def test_egrep_with_error
   end
 
   def test_existing
-    fl = FileList["abc.c", "notthere.c"]
+    fl = FileList["*c.c", "notthere.c", "a*.c"]
     assert_equal ["abc.c"], fl.existing
     assert fl.existing.is_a?(FileList)
   end
 
   def test_existing!
-    fl = FileList["abc.c", "notthere.c"]
+    fl = FileList["*c.c", "notthere.c", "a*.c"]
     result = fl.existing!
     assert_equal ["abc.c"], fl
     assert_equal fl.object_id, result.object_id
diff --git a/test/test_rake_file_list_path_map.rb b/test/test_rake_file_list_path_map.rb
index 28953a97a..2c51a2d72 100644
--- a/test/test_rake_file_list_path_map.rb
+++ b/test/test_rake_file_list_path_map.rb
@@ -1,6 +1,7 @@
+# frozen_string_literal: true
 require File.expand_path("../helper", __FILE__)
 
-class TestRakeFileListPathMap < Rake::TestCase
+class TestRakeFileListPathMap < Rake::TestCase # :nodoc:
   def test_file_list_supports_pathmap
     assert_equal ["a", "b"], FileList["dir/a.rb", "dir/b.rb"].pathmap("%n")
   end
diff --git a/test/test_rake_file_task.rb b/test/test_rake_file_task.rb
index 24614dabe..61303d88a 100644
--- a/test/test_rake_file_task.rb
+++ b/test/test_rake_file_task.rb
@@ -1,8 +1,9 @@
+# frozen_string_literal: true
 require File.expand_path("../helper", __FILE__)
 require "fileutils"
 require "pathname"
 
-class TestRakeFileTask < Rake::TestCase
+class TestRakeFileTask < Rake::TestCase # :nodoc:
   include Rake
 
   def setup
diff --git a/test/test_rake_file_utils.rb b/test/test_rake_file_utils.rb
index 218c25415..7e9674fdc 100644
--- a/test/test_rake_file_utils.rb
+++ b/test/test_rake_file_utils.rb
@@ -1,8 +1,9 @@
+# frozen_string_literal: true
 require File.expand_path("../helper", __FILE__)
 require "fileutils"
 require "stringio"
 
-class TestRakeFileUtils < Rake::TestCase
+class TestRakeFileUtils < Rake::TestCase # :nodoc:
   def setup
     super
     @rake_test_sh = ENV["RAKE_TEST_SH"]
@@ -46,7 +47,7 @@ def test_ln
     assert_equal "TEST_LN\n", File.read("b")
   end
 
-  class BadLink
+  class BadLink # :nodoc:
     include Rake::FileUtilsExt
     attr_reader :cp_args
 
@@ -180,6 +181,15 @@ def test_sh_with_spawn_options
     assert_equal "echocommand.rb\n", r.read
   end
 
+  def test_sh_with_hash_option
+    skip "JRuby does not support spawn options" if jruby?
+    check_expansion
+
+    verbose(false) {
+      sh "#{RUBY} check_expansion.rb", { chdir: "." }, verbose: false
+    }
+  end
+
   def test_sh_failure
     shellcommand
 
diff --git a/test/test_rake_functional.rb b/test/test_rake_functional.rb
index 7c2bd3266..afc31d28f 100644
--- a/test/test_rake_functional.rb
+++ b/test/test_rake_functional.rb
@@ -1,8 +1,9 @@
+# frozen_string_literal: true
 require File.expand_path("../helper", __FILE__)
 require "fileutils"
 require "open3"
 
-class TestRakeFunctional < Rake::TestCase
+class TestRakeFunctional < Rake::TestCase # :nodoc:
   include RubyRunner
 
   def setup
@@ -295,6 +296,26 @@ def test_rules_chaining_to_file_task
            "'play.app' file should exist"
   end
 
+  def dryrun_tasks
+    @err.split("\n").select { |line|
+      line.match(/^\*\* Execute/)
+    }.map { |line|
+      line.gsub(/^\*\* Execute \(dry run\) /, "")
+    }
+  end
+
+  def test_update_midway_through_chaining_to_file_task
+    rakefile_file_chains
+
+    rake "-n"
+    assert_equal(%w{fileA fileB fileC default}, dryrun_tasks)
+    rake
+    sleep 1 # Ensure the timestamp is on a new second
+    FileUtils.touch("fileA")
+    rake "-n"
+    assert_equal(%w{fileB fileC default}, dryrun_tasks)
+  end
+
   def test_file_creation_task
     rakefile_file_creation
 
diff --git a/test/test_rake_invocation_chain.rb b/test/test_rake_invocation_chain.rb
index ba5f8724f..bf918f758 100644
--- a/test/test_rake_invocation_chain.rb
+++ b/test/test_rake_invocation_chain.rb
@@ -1,6 +1,7 @@
+# frozen_string_literal: true
 require File.expand_path("../helper", __FILE__)
 
-class TestRakeInvocationChain < Rake::TestCase
+class TestRakeInvocationChain < Rake::TestCase # :nodoc:
   include Rake
 
   def setup
diff --git a/test/test_rake_late_time.rb b/test/test_rake_late_time.rb
index a88826da7..776b02d22 100644
--- a/test/test_rake_late_time.rb
+++ b/test/test_rake_late_time.rb
@@ -1,6 +1,7 @@
+# frozen_string_literal: true
 require File.expand_path("../helper", __FILE__)
 
-class TestRakeLateTime < Rake::TestCase
+class TestRakeLateTime < Rake::TestCase # :nodoc:
   def test_late_time_comparisons
     late = Rake::LATE
     assert_equal late, late
diff --git a/test/test_rake_linked_list.rb b/test/test_rake_linked_list.rb
index a3c4d1972..656b50ac2 100644
--- a/test/test_rake_linked_list.rb
+++ b/test/test_rake_linked_list.rb
@@ -1,6 +1,7 @@
+# frozen_string_literal: true
 require File.expand_path("../helper", __FILE__)
 
-class TestLinkedList < Rake::TestCase
+class TestLinkedList < Rake::TestCase # :nodoc:
   include Rake
 
   def test_empty_list
diff --git a/test/test_rake_makefile_loader.rb b/test/test_rake_makefile_loader.rb
index bd70fd3b6..4f5270e0a 100644
--- a/test/test_rake_makefile_loader.rb
+++ b/test/test_rake_makefile_loader.rb
@@ -1,7 +1,8 @@
+# frozen_string_literal: true
 require File.expand_path("../helper", __FILE__)
 require "rake/loaders/makefile"
 
-class TestRakeMakefileLoader < Rake::TestCase
+class TestRakeMakefileLoader < Rake::TestCase  # :nodoc:
   include Rake
 
   def test_parse
diff --git a/test/test_rake_multi_task.rb b/test/test_rake_multi_task.rb
index bab25b158..641e65f4b 100644
--- a/test/test_rake_multi_task.rb
+++ b/test/test_rake_multi_task.rb
@@ -1,9 +1,9 @@
+# frozen_string_literal: true
 require File.expand_path("../helper", __FILE__)
 require "thread"
 
-class TestRakeMultiTask < Rake::TestCase
+class TestRakeMultiTask < Rake::TestCase # :nodoc:
   include Rake
-  include Rake::DSL
 
   def setup
     super
@@ -82,4 +82,25 @@ def test_cross_thread_prerequisite_failures
       Rake::Task[:b].invoke
     end
   end
+
+  def test_task_not_executed_if_dependant_task_failed_concurrently
+    multitask default: [:one, :two]
+
+    task :one do
+      raise
+    end
+
+    task_two_was_executed = false
+    task two: :one do
+      task_two_was_executed = true
+    end
+
+    begin
+      Rake::Task[:default].invoke
+    rescue RuntimeError
+    ensure
+      sleep 0.5
+      refute task_two_was_executed
+    end
+  end
 end
diff --git a/test/test_rake_name_space.rb b/test/test_rake_name_space.rb
index e043c07fa..a1a814cfd 100644
--- a/test/test_rake_name_space.rb
+++ b/test/test_rake_name_space.rb
@@ -1,8 +1,9 @@
+# frozen_string_literal: true
 require File.expand_path("../helper", __FILE__)
 
-class TestRakeNameSpace < Rake::TestCase
+class TestRakeNameSpace < Rake::TestCase # :nodoc:
 
-  class TM
+  class TM # :nodoc:
     include Rake::TaskManager
   end
 
diff --git a/test/test_rake_package_task.rb b/test/test_rake_package_task.rb
index 7bacb7a52..d3886f8ca 100644
--- a/test/test_rake_package_task.rb
+++ b/test/test_rake_package_task.rb
@@ -1,7 +1,8 @@
+# frozen_string_literal: true
 require File.expand_path("../helper", __FILE__)
 require "rake/packagetask"
 
-class TestRakePackageTask < Rake::TestCase
+class TestRakePackageTask < Rake::TestCase # :nodoc:
 
   def test_initialize
     touch "install.rb"
diff --git a/test/test_rake_path_map.rb b/test/test_rake_path_map.rb
index 040692930..1551247ec 100644
--- a/test/test_rake_path_map.rb
+++ b/test/test_rake_path_map.rb
@@ -1,6 +1,7 @@
+# frozen_string_literal: true
 require File.expand_path("../helper", __FILE__)
 
-class TestRakePathMap < Rake::TestCase
+class TestRakePathMap < Rake::TestCase  # :nodoc:
 
   def test_returns_self_with_no_args
     assert_equal "abc.rb", "abc.rb".pathmap
diff --git a/test/test_rake_path_map_explode.rb b/test/test_rake_path_map_explode.rb
index 554a02266..877a8e0c9 100644
--- a/test/test_rake_path_map_explode.rb
+++ b/test/test_rake_path_map_explode.rb
@@ -1,6 +1,7 @@
+# frozen_string_literal: true
 require File.expand_path("../helper", __FILE__)
 
-class TestRakePathMapExplode < Rake::TestCase
+class TestRakePathMapExplode < Rake::TestCase # :nodoc:
   def setup
     super
 
diff --git a/test/test_rake_path_map_partial.rb b/test/test_rake_path_map_partial.rb
index 0adc24313..e73ec56b6 100644
--- a/test/test_rake_path_map_partial.rb
+++ b/test/test_rake_path_map_partial.rb
@@ -1,8 +1,9 @@
+# frozen_string_literal: true
 require File.expand_path("../helper", __FILE__)
 
-class TestRakePathMapPartial < Rake::TestCase
+class TestRakePathMapPartial < Rake::TestCase # :nodoc:
   def test_pathmap_partial
-    @path = "1/2/file"
+    @path = "1/2/file".dup
     def @path.call(n)
       pathmap_partial(n)
     end
diff --git a/test/test_rake_pseudo_status.rb b/test/test_rake_pseudo_status.rb
index d9fe42216..008621f49 100644
--- a/test/test_rake_pseudo_status.rb
+++ b/test/test_rake_pseudo_status.rb
@@ -1,6 +1,7 @@
+# frozen_string_literal: true
 require File.expand_path("../helper", __FILE__)
 
-class TestRakePseudoStatus < Rake::TestCase
+class TestRakePseudoStatus < Rake::TestCase # :nodoc:
   def test_with_zero_exit_status
     s = Rake::PseudoStatus.new
     assert_equal 0, s.exitstatus
diff --git a/test/test_rake_rake_test_loader.rb b/test/test_rake_rake_test_loader.rb
index 21c494ffe..4423a9b1c 100644
--- a/test/test_rake_rake_test_loader.rb
+++ b/test/test_rake_rake_test_loader.rb
@@ -1,6 +1,13 @@
+# frozen_string_literal: true
 require File.expand_path("../helper", __FILE__)
 
-class TestRakeRakeTestLoader < Rake::TestCase
+class TestRakeRakeTestLoader < Rake::TestCase # :nodoc:
+
+  def setup
+    super
+
+    @loader = File.join @rake_lib, "rake/rake_test_loader.rb"
+  end
 
   def test_pattern
     orig_loaded_features = $:.dup
@@ -10,11 +17,45 @@ def test_pattern
 
     ARGV.replace %w[foo.rb test_*.rb -v]
 
-    load File.join(@rake_lib, "rake/rake_test_loader.rb")
+    load @loader
 
     assert_equal %w[-v], ARGV
   ensure
     $:.replace orig_loaded_features
   end
 
+  def test_load_error_from_require
+    out, err = capture_io do
+      ARGV.replace %w[no_such_test_file.rb]
+
+      assert_raises SystemExit do
+        load @loader
+      end
+    end
+
+    assert_empty out
+
+    no_such_path = File.join @tempdir, "no_such_test_file"
+
+    expected =
+      /\A\n
+       File\ does\ not\ exist:\ #{no_such_path}(\.rb)? # JRuby is different
+       \n\n\Z/x
+
+    assert_match expected, err
+  end
+
+  def test_load_error_raised_explicitly
+    File.write("error_test.rb", "raise LoadError, 'explicitly raised'")
+    out, err = capture_io do
+      ARGV.replace %w[error_test.rb]
+
+      exc = assert_raises(LoadError) do
+        load @loader
+      end
+      assert_equal "explicitly raised", exc.message
+    end
+    assert_empty out
+    assert_empty err
+  end
 end
diff --git a/test/test_rake_reduce_compat.rb b/test/test_rake_reduce_compat.rb
index de81b474b..17986dcde 100644
--- a/test/test_rake_reduce_compat.rb
+++ b/test/test_rake_reduce_compat.rb
@@ -1,7 +1,8 @@
+# frozen_string_literal: true
 require File.expand_path("../helper", __FILE__)
 require "open3"
 
-class TestRakeReduceCompat < Rake::TestCase
+class TestRakeReduceCompat < Rake::TestCase # :nodoc:
   include RubyRunner
 
   def invoke_normal(task_name)
diff --git a/test/test_rake_require.rb b/test/test_rake_require.rb
index c77344cc3..6309277da 100644
--- a/test/test_rake_require.rb
+++ b/test/test_rake_require.rb
@@ -1,6 +1,7 @@
+# frozen_string_literal: true
 require File.expand_path("../helper", __FILE__)
 
-class TestRakeRequire < Rake::TestCase
+class TestRakeRequire < Rake::TestCase # :nodoc:
   def setup
     super
     $LOAD_PATH.unshift "." if jruby17?
diff --git a/test/test_rake_rules.rb b/test/test_rake_rules.rb
index 7806ed11c..bfb8e775f 100644
--- a/test/test_rake_rules.rb
+++ b/test/test_rake_rules.rb
@@ -1,7 +1,8 @@
+# frozen_string_literal: true
 require File.expand_path("../helper", __FILE__)
 require "fileutils"
 
-class TestRakeRules < Rake::TestCase
+class TestRakeRules < Rake::TestCase # :nodoc:
   include Rake
 
   SRCFILE    = "abc.c"
@@ -10,6 +11,7 @@ class TestRakeRules < Rake::TestCase
   OBJFILE    = "abc.o"
   FOOFILE    = "foo"
   DOTFOOFILE = ".foo"
+  MINFILE    = "abc.min.o"
 
   def setup
     super
@@ -341,6 +343,17 @@ def test_regex_rule_with_args
     Task[OBJFILE].invoke("arg")
   end
 
+  # for https://github.com/ruby/rake/pull/182
+  def test_single_dependent_with_nil_args
+    create_file(SRCFILE)
+    rule nil => ".cpp" do |t| p t.name end
+    rule(/\.o$/ => ".c") do |t|
+      @runs << t.name
+    end
+    Task[OBJFILE].invoke
+    assert_equal [OBJFILE], @runs
+  end
+
   def test_string_rule_with_args_and_lambda_prereq
     delete_file(OBJFILE)
     create_file(SRCFILE)
@@ -385,4 +398,15 @@ def obj.find_prereq(task_name)
     assert_equal ["#{OBJFILE} - abc.c"], @runs
   end
 
+  def test_works_with_chained_extensions_in_rules
+    create_file(OBJFILE)
+    rule(".min.o" => [".o"]) do |t|
+      @runs << t.name
+      assert_equal OBJFILE, t.source
+      assert_equal MINFILE, t.name
+    end
+    Task[MINFILE].invoke
+    assert_equal [MINFILE], @runs
+  end
+
 end
diff --git a/test/test_rake_scope.rb b/test/test_rake_scope.rb
index 169c0d9f9..24ac03408 100644
--- a/test/test_rake_scope.rb
+++ b/test/test_rake_scope.rb
@@ -1,6 +1,7 @@
+# frozen_string_literal: true
 require File.expand_path("../helper", __FILE__)
 
-class TestRakeScope < Rake::TestCase
+class TestRakeScope < Rake::TestCase # :nodoc:
   include Rake
 
   def test_path_against_empty_scope
diff --git a/test/test_rake_task.rb b/test/test_rake_task.rb
index 5f5a63e30..688e0a3e7 100644
--- a/test/test_rake_task.rb
+++ b/test/test_rake_task.rb
@@ -1,7 +1,8 @@
+# frozen_string_literal: true
 require File.expand_path("../helper", __FILE__)
 require "fileutils"
 
-class TestRakeTask < Rake::TestCase
+class TestRakeTask < Rake::TestCase # :nodoc:
   include Rake
 
   def setup
@@ -61,10 +62,14 @@ def test_invoke_with_circular_dependencies
   end
 
   def test_dry_run_prevents_actions
-    Rake.application.options.dryrun = true
     runlist = []
     t1 = task(:t1) { |t| runlist << t.name; 3321 }
-    _, err = capture_io { t1.invoke }
+    _, err = capture_io {
+      Rake.application.set_default_options # reset trace output IO
+      Rake.application.options.dryrun = true
+
+      t1.invoke
+    }
     assert_match(/execute .*t1/i, err)
     assert_match(/dry run/i, err)
     refute_match(/invoke/i, err)
@@ -74,9 +79,11 @@ def test_dry_run_prevents_actions
   end
 
   def test_tasks_can_be_traced
-    Rake.application.options.trace = true
     t1 = task(:t1)
     _, err = capture_io {
+      Rake.application.set_default_options # reset trace output IO
+      Rake.application.options.trace = true
+
       t1.invoke
     }
     assert_match(/invoke t1/i, err)
@@ -165,7 +172,8 @@ def test_find
     task :tfind
     assert_equal "tfind", Task[:tfind].name
     ex = assert_raises(RuntimeError) { Task[:leaves] }
-    assert_equal "Don't know how to build task 'leaves' (see --tasks)", ex.message
+    assert_equal "Don't know how to build task 'leaves'" \
+      " (See the list of available tasks with `rake --tasks`)", ex.message
   end
 
   def test_defined
@@ -452,4 +460,20 @@ def test_source_is_first_prerequisite
     t = task t: ["preqA", "preqB"]
     assert_equal "preqA", t.source
   end
+
+  def test_suggests_valid_rake_task_names
+    task :test
+    error = assert_raises(RuntimeError) { Task[:testt] }
+
+    assert_match(/Don\'t know how to build task \'testt\'/, error.message)
+
+    if defined?(::DidYouMean::SpellChecker) && defined?(::DidYouMean::Formatter)
+      assert_match(/Did you mean\?  test/, error.message)
+    end
+  end
+
+  def test_prereqs
+    t = task(a: %w[b c d e])
+    assert_equal %w[b c d e], t.prereqs
+  end
 end
diff --git a/test/test_rake_task_argument_parsing.rb b/test/test_rake_task_argument_parsing.rb
index 4bc0ff0ae..ed12ea0b4 100644
--- a/test/test_rake_task_argument_parsing.rb
+++ b/test/test_rake_task_argument_parsing.rb
@@ -1,6 +1,7 @@
+# frozen_string_literal: true
 require File.expand_path("../helper", __FILE__)
 
-class TestRakeTaskArgumentParsing < Rake::TestCase
+class TestRakeTaskArgumentParsing < Rake::TestCase # :nodoc:
   def setup
     super
 
@@ -37,6 +38,12 @@ def test_can_handle_spaces_between_args
     assert_equal ["one", "two", "three", "four"], args
   end
 
+  def test_can_handle_spaces_between_all_args
+    name, args = @app.parse_task_string("name[ one , two ,\tthree , \tfour ]")
+    assert_equal "name", name
+    assert_equal ["one", "two", "three", "four"], args
+  end
+
   def test_keeps_embedded_spaces
     name, args = @app.parse_task_string("name[a one ana, two]")
     assert_equal "name", name
@@ -95,16 +102,14 @@ def @app.unix?() raise end
   end
 
   def test_no_rakeopt
-    ARGV << "--trace"
     app = Rake::Application.new
-    app.init
+    app.init %w[--trace]
     assert !app.options.silent
   end
 
   def test_rakeopt_with_blank_options
-    ARGV << "--trace"
     app = Rake::Application.new
-    app.init
+    app.init %w[--trace]
     assert !app.options.silent
   end
 
diff --git a/test/test_rake_task_arguments.rb b/test/test_rake_task_arguments.rb
index 383d4a172..245a71661 100644
--- a/test/test_rake_task_arguments.rb
+++ b/test/test_rake_task_arguments.rb
@@ -1,6 +1,7 @@
+# frozen_string_literal: true
 require File.expand_path("../helper", __FILE__)
 
-class TestRakeTaskArguments < Rake::TestCase
+class TestRakeTaskArguments < Rake::TestCase # :nodoc:
   def teardown
     ENV.delete("rev")
     ENV.delete("VER")
diff --git a/test/test_rake_task_manager.rb b/test/test_rake_task_manager.rb
index a611bd737..88937c604 100644
--- a/test/test_rake_task_manager.rb
+++ b/test/test_rake_task_manager.rb
@@ -1,6 +1,7 @@
+# frozen_string_literal: true
 require File.expand_path("../helper", __FILE__)
 
-class TestRakeTaskManager < Rake::TestCase
+class TestRakeTaskManager < Rake::TestCase # :nodoc:
 
   def setup
     super
@@ -24,7 +25,17 @@ def test_index
       @tm["bad"]
     end
 
-    assert_equal "Don't know how to build task 'bad' (see --tasks)", e.message
+    assert_equal "Don't know how to build task 'bad' (See the list of available tasks with `rake --tasks`)", e.message
+  end
+
+  def test_undefined_task_with_custom_application
+    Rake.application.init("myrake", nil)
+
+    e = assert_raises RuntimeError do
+      @tm["bad"]
+    end
+
+    assert_equal "Don't know how to build task 'bad' (See the list of available tasks with `myrake --tasks`)", e.message
   end
 
   def test_name_lookup
diff --git a/test/test_rake_task_manager_argument_resolution.rb b/test/test_rake_task_manager_argument_resolution.rb
index 6d292816d..585932c5c 100644
--- a/test/test_rake_task_manager_argument_resolution.rb
+++ b/test/test_rake_task_manager_argument_resolution.rb
@@ -1,6 +1,7 @@
+# frozen_string_literal: true
 require File.expand_path("../helper", __FILE__)
 
-class TestRakeTaskManagerArgumentResolution < Rake::TestCase
+class TestRakeTaskManagerArgumentResolution < Rake::TestCase # :nodoc:
 
   def test_good_arg_patterns
     assert_equal [:t, [], []],       task(:t)
diff --git a/test/test_rake_task_with_arguments.rb b/test/test_rake_task_with_arguments.rb
index 5f71b6b1a..46edcd112 100644
--- a/test/test_rake_task_with_arguments.rb
+++ b/test/test_rake_task_with_arguments.rb
@@ -1,6 +1,7 @@
+# frozen_string_literal: true
 require File.expand_path("../helper", __FILE__)
 
-class TestRakeTaskWithArguments < Rake::TestCase
+class TestRakeTaskWithArguments < Rake::TestCase # :nodoc:
   include Rake
 
   def setup
@@ -83,7 +84,7 @@ def test_actions_of_various_arity_are_ok_with_args
   def test_actions_adore_keywords
     # A brutish trick to avoid parsing. Remove it once support for 1.9 and 2.0 is dropped
     # https://ci.appveyor.com/project/ruby/rake/build/1.0.301
-    skip 'Keywords aren\'t a feature in this version' if RUBY_VERSION =~ /^1|^2\.0/
+    skip "Keywords aren't a feature in this version" if RUBY_VERSION =~ /^1|^2\.0/
     # https://github.com/ruby/rake/pull/174#issuecomment-263460761
     skip if jruby9?
     eval <<-RUBY, binding, __FILE__, __LINE__+1
diff --git a/test/test_rake_test_task.rb b/test/test_rake_test_task.rb
index 8e422f164..ed2313b91 100644
--- a/test/test_rake_test_task.rb
+++ b/test/test_rake_test_task.rb
@@ -1,7 +1,8 @@
+# frozen_string_literal: true
 require File.expand_path("../helper", __FILE__)
 require "rake/testtask"
 
-class TestRakeTestTask < Rake::TestCase
+class TestRakeTestTask < Rake::TestCase # :nodoc:
   include Rake
 
   def test_initialize
diff --git a/test/test_rake_thread_pool.rb b/test/test_rake_thread_pool.rb
index d365574ba..42f648854 100644
--- a/test/test_rake_thread_pool.rb
+++ b/test/test_rake_thread_pool.rb
@@ -1,7 +1,8 @@
+# frozen_string_literal: true
 require File.expand_path("../helper", __FILE__)
 require "rake/thread_pool"
 
-class TestRakeTestThreadPool < Rake::TestCase
+class TestRakeTestThreadPool < Rake::TestCase # :nodoc:
   include Rake
 
   def test_pool_executes_in_current_thread_for_zero_threads
diff --git a/test/test_rake_top_level_functions.rb b/test/test_rake_top_level_functions.rb
index a3bb2fbb8..f0dec1b76 100644
--- a/test/test_rake_top_level_functions.rb
+++ b/test/test_rake_top_level_functions.rb
@@ -1,6 +1,7 @@
+# frozen_string_literal: true
 require File.expand_path("../helper", __FILE__)
 
-class TestRakeTopLevelFunctions < Rake::TestCase
+class TestRakeTopLevelFunctions < Rake::TestCase # :nodoc:
 
   def setup
     super
diff --git a/test/test_rake_win32.rb b/test/test_rake_win32.rb
index be95adb92..ed08ef09e 100644
--- a/test/test_rake_win32.rb
+++ b/test/test_rake_win32.rb
@@ -1,8 +1,9 @@
+# frozen_string_literal: true
 require File.expand_path("../helper", __FILE__)
 
-class TestRakeWin32 < Rake::TestCase
+class TestRakeWin32 < Rake::TestCase # :nodoc:
 
-  Win32 = Rake::Win32
+  Win32 = Rake::Win32 # :nodoc:
 
   def test_win32_system_dir_uses_home_if_defined
     ENV["HOME"] = 'C:\\HP'
@@ -64,7 +65,11 @@ def test_win32_backtrace_with_different_case
     rake.options.trace = true
     rake.instance_variable_set(:@rakefile, "Rakefile")
 
-    _, err = capture_io { rake.display_error_message(ex) }
+    _, err = capture_io {
+      rake.set_default_options # reset trace output IO
+
+      rake.display_error_message(ex)
+    }
 
     assert_match(/rakefile/, err)
   end
diff --git a/test/test_thread_history_display.rb b/test/test_thread_history_display.rb
index f3466cef7..026576446 100644
--- a/test/test_thread_history_display.rb
+++ b/test/test_thread_history_display.rb
@@ -1,8 +1,9 @@
+# frozen_string_literal: true
 require File.expand_path("../helper", __FILE__)
 
 require "rake/thread_history_display"
 
-class TestThreadHistoryDisplay < Rake::TestCase
+class TestThreadHistoryDisplay < Rake::TestCase # :nodoc:
   def setup
     super
     @time = 1_000_000
diff --git a/test/test_trace_output.rb b/test/test_trace_output.rb
index 18d2eee0f..46403870f 100644
--- a/test/test_trace_output.rb
+++ b/test/test_trace_output.rb
@@ -1,14 +1,15 @@
+# frozen_string_literal: true
 require File.expand_path("../helper", __FILE__)
 require "stringio"
 
-class TestTraceOutput < Rake::TestCase
+class TestTraceOutput < Rake::TestCase # :nodoc:
   include Rake::TraceOutput
 
-  class PrintSpy
+  class PrintSpy # :nodoc:
     attr_reader :result, :calls
 
     def initialize
-      @result = ""
+      @result = "".dup
       @calls = 0
     end