eval_gemfile + LTS support

.github/workflows/main.yml

@@ -17,6 +17,7 @@ jobs:
       fail-fast: false
       matrix:
         ruby:
+          - '3.4'
           - '3.3'
           - '3.2'
           - '3.1'
@@ -41,7 +42,11 @@ jobs:
         run: |
           case ${RUBY_VERSION} in
             truffleruby|truffleruby-head)
-              gem install bundler -v 2.5.18
+              gem install bundler -v 2.5.23
+            ;;
+
+            3.0)
+              gem install bundler -v 2.5.23
             ;;
 
             *)

.rubocop.yml

@@ -0,0 +1,17 @@
+inherit_gem:
+  rubocop-lts: config/rubygem_rspec.yml
+
+RSpec/ExampleLength:
+  Enabled: false
+
+RSpec/MultipleExpectations:
+  Enabled: false
+
+RSpec/DescribeClass:
+  Enabled: false
+
+# TODO: We would need to implement Mutexes in order to make violations thread safe.
+#       But even then they would still trigger the violation.
+#       See: https://coderscat.com/ruby-change-current-working-directory/
+ThreadSafety/DirChdir:
+  Enabled: false

.rubocop_gradual.lock

@@ -0,0 +1,111 @@
+{
+  "Gemfile:3311641552": [
+    [19, 3, 4, "Security/Eval: The use of `eval` is a serious security risk.", 2087429787],
+    [21, 3, 4, "Security/Eval: The use of `eval` is a serious security risk.", 2087429787],
+    [23, 3, 4, "Security/Eval: The use of `eval` is a serious security risk.", 2087429787]
+  ],
+  "bin/bundle:3123891436": [
+    [66, 5, 20, "ThreadSafety/ClassInstanceVariable: Avoid class instance variables.", 2485198147]
+  ],
+  "lib/appraisal/appraisal_file.rb:3486777149": [
+    [13, 5, 52, "Style/ClassMethodsDefinitions: Use `class << self` to define a class method.", 946226050]
+  ],
+  "lib/appraisal/cli.rb:435288507": [
+    [116, 5, 410, "Style/MissingRespondToMissing: When using `method_missing`, define `respond_to_missing?`.", 1969529734]
+  ],
+  "lib/appraisal/customize.rb:190316824": [
+    [10, 5, 138, "Style/ClassMethodsDefinitions: Use `class << self` to define a class method.", 2682968747],
+    [17, 5, 62, "Style/ClassMethodsDefinitions: Use `class << self` to define a class method.", 4082816720],
+    [21, 5, 516, "Style/ClassMethodsDefinitions: Use `class << self` to define a class method.", 2780620929]
+  ],
+  "lib/appraisal/utils.rb:2308689703": [
+    [6, 5, 129, "Style/ClassMethodsDefinitions: Use `class << self` to define a class method.", 733338411],
+    [13, 5, 354, "Style/ClassMethodsDefinitions: Use `class << self` to define a class method.", 119295155],
+    [35, 5, 152, "Style/ClassMethodsDefinitions: Use `class << self` to define a class method.", 1306460482],
+    [42, 5, 151, "Style/ClassMethodsDefinitions: Use `class << self` to define a class method.", 1120325158],
+    [48, 5, 97, "Style/ClassMethodsDefinitions: Use `class << self` to define a class method.", 2744794681],
+    [52, 5, 244, "Style/ClassMethodsDefinitions: Use `class << self` to define a class method.", 1461524090],
+    [61, 5, 111, "Style/ClassMethodsDefinitions: Use `class << self` to define a class method.", 1909626476]
+  ],
+  "spec/acceptance/cli/clean_spec.rb:1398207731": [
+    [5, 23, 17, "RSpec/DescribeMethod: The second argument to describe should be the method being tested. '#instance' or '.class'.", 1606893221]
+  ],
+  "spec/acceptance/cli/generate_spec.rb:1599585127": [
+    [5, 23, 20, "RSpec/DescribeMethod: The second argument to describe should be the method being tested. '#instance' or '.class'.", 3905826443]
+  ],
+  "spec/acceptance/cli/help_spec.rb:3832542771": [
+    [5, 23, 16, "RSpec/DescribeMethod: The second argument to describe should be the method being tested. '#instance' or '.class'.", 2148351217]
+  ],
+  "spec/acceptance/cli/install_spec.rb:2827187127": [
+    [5, 23, 19, "RSpec/DescribeMethod: The second argument to describe should be the method being tested. '#instance' or '.class'.", 3284642881]
+  ],
+  "spec/acceptance/cli/list_spec.rb:1943273700": [
+    [5, 23, 16, "RSpec/DescribeMethod: The second argument to describe should be the method being tested. '#instance' or '.class'.", 2152687586]
+  ],
+  "spec/acceptance/cli/update_spec.rb:2524405540": [
+    [5, 23, 18, "RSpec/DescribeMethod: The second argument to describe should be the method being tested. '#instance' or '.class'.", 3752509585]
+  ],
+  "spec/acceptance/cli/version_spec.rb:4076882072": [
+    [5, 23, 19, "RSpec/DescribeMethod: The second argument to describe should be the method being tested. '#instance' or '.class'.", 316256858]
+  ],
+  "spec/appraisal/appraisal_file_spec.rb:1896479557": [
+    [28, 18, 7, "RSpec/NamedSubject: Name your test subject if you need to reference it explicitly.", 1892732441],
+    [33, 7, 57, "RSpec/NestedGroups: Maximum example group nesting exceeded [4/3].", 511689843],
+    [41, 20, 7, "RSpec/NamedSubject: Name your test subject if you need to reference it explicitly.", 1892732441],
+    [41, 33, 39, "RSpec/ExpectChange: Prefer `change(Appraisal::Customize, :heading)`.", 513325635],
+    [45, 7, 63, "RSpec/NestedGroups: Maximum example group nesting exceeded [4/3].", 1527582647],
+    [53, 20, 7, "RSpec/NamedSubject: Name your test subject if you need to reference it explicitly.", 1892732441],
+    [53, 33, 45, "RSpec/ExpectChange: Prefer `change(Appraisal::Customize, :single_quotes)`.", 627072007],
+    [57, 7, 77, "RSpec/NestedGroups: Maximum example group nesting exceeded [4/3].", 1960750461],
+    [65, 11, 7, "RSpec/NamedSubject: Name your test subject if you need to reference it explicitly.", 1892732441]
+  ],
+  "spec/appraisal/appraisal_spec.rb:1242607413": [
+    [33, 11, 23, "RSpec/ContextWording: Context description should match /^when\\b/, /^with\\b/, or /^without\\b/.", 2511581329],
+    [90, 11, 23, "RSpec/ContextWording: Context description should match /^when\\b/, /^with\\b/, or /^without\\b/.", 1120511218],
+    [95, 7, 83, "RSpec/ReceiveMessages: Use `receive_messages` instead of multiple stubs on lines [96].", 1453890366],
+    [95, 13, 10, "RSpec/InstanceVariable: Avoid instance variables - use let, a method call, or a local variable (if possible).", 4097172192],
+    [96, 7, 82, "RSpec/ReceiveMessages: Use `receive_messages` instead of multiple stubs on lines [95].", 1614459968],
+    [96, 13, 10, "RSpec/InstanceVariable: Avoid instance variables - use let, a method call, or a local variable (if possible).", 4097172192],
+    [97, 61, 20, "RSpec/VerifiedDoubles: Prefer using verifying doubles over normal doubles.", 2281802167],
+    [104, 9, 10, "RSpec/InstanceVariable: Avoid instance variables - use let, a method call, or a local variable (if possible).", 4097172192],
+    [114, 7, 10, "RSpec/InstanceVariable: Avoid instance variables - use let, a method call, or a local variable (if possible).", 4097172192],
+    [120, 7, 10, "RSpec/InstanceVariable: Avoid instance variables - use let, a method call, or a local variable (if possible).", 4097172192],
+    [126, 7, 10, "RSpec/InstanceVariable: Avoid instance variables - use let, a method call, or a local variable (if possible).", 4097172192]
+  ],
+  "spec/appraisal/customize_spec.rb:1577209079": [
+    [7, 1, 4439, "RSpec/MultipleMemoizedHelpers: Example group has too many memoized helpers [6/5]", 3030165271],
+    [17, 3, 13, "RSpec/SubjectDeclaration: Use subject explicitly rather than using let", 3282510975],
+    [25, 3, 564, "RSpec/MultipleMemoizedHelpers: Example group has too many memoized helpers [6/5]", 3336288078],
+    [27, 7, 7, "RSpec/NamedSubject: Name your test subject if you need to reference it explicitly.", 1892732441],
+    [43, 3, 286, "RSpec/MultipleMemoizedHelpers: Example group has too many memoized helpers [6/5]", 4222920637],
+    [45, 7, 7, "RSpec/NamedSubject: Name your test subject if you need to reference it explicitly.", 1892732441],
+    [55, 3, 2985, "RSpec/MultipleMemoizedHelpers: Example group has too many memoized helpers [13/5]", 1576524985],
+    [65, 7, 62, "RSpec/ReceiveMessages: Use `receive_messages` instead of multiple stubs on lines [66, 67, 68].", 123979604],
+    [66, 7, 72, "RSpec/ReceiveMessages: Use `receive_messages` instead of multiple stubs on lines [65, 67, 68].", 3240119264],
+    [67, 7, 74, "RSpec/ReceiveMessages: Use `receive_messages` instead of multiple stubs on lines [65, 66, 68].", 3701550880],
+    [68, 7, 85, "RSpec/ReceiveMessages: Use `receive_messages` instead of multiple stubs on lines [65, 66, 67].", 3874694796],
+    [72, 7, 7, "RSpec/NamedSubject: Name your test subject if you need to reference it explicitly.", 1892732441]
+  ],
+  "spec/appraisal/gemfile_spec.rb:3323881535": [
+    [227, 11, 17, "RSpec/ContextWording: Context description should match /^when\\b/, /^with\\b/, or /^without\\b/.", 3608128140],
+    [228, 13, 13, "RSpec/ContextWording: Context description should match /^when\\b/, /^with\\b/, or /^without\\b/.", 420381022],
+    [235, 13, 15, "RSpec/ContextWording: Context description should match /^when\\b/, /^with\\b/, or /^without\\b/.", 3511037132],
+    [245, 13, 12, "RSpec/ContextWording: Context description should match /^when\\b/, /^with\\b/, or /^without\\b/.", 3100155342],
+    [255, 11, 24, "RSpec/ContextWording: Context description should match /^when\\b/, /^with\\b/, or /^without\\b/.", 3242693747],
+    [258, 13, 17, "RSpec/ContextWording: Context description should match /^when\\b/, /^with\\b/, or /^without\\b/.", 105800534],
+    [281, 13, 16, "RSpec/ContextWording: Context description should match /^when\\b/, /^with\\b/, or /^without\\b/.", 179066369],
+    [312, 13, 15, "RSpec/ContextWording: Context description should match /^when\\b/, /^with\\b/, or /^without\\b/.", 3912615366],
+    [356, 13, 14, "RSpec/ContextWording: Context description should match /^when\\b/, /^with\\b/, or /^without\\b/.", 2832187185],
+    [414, 13, 22, "RSpec/ContextWording: Context description should match /^when\\b/, /^with\\b/, or /^without\\b/.", 772581599],
+    [424, 11, 20, "RSpec/ContextWording: Context description should match /^when\\b/, /^with\\b/, or /^without\\b/.", 1076107314]
+  ],
+  "spec/appraisal/utils_spec.rb:2286225770": [
+    [62, 17, 58, "RSpec/VerifiedDoubles: Prefer using verifying doubles over normal doubles.", 1573223692]
+  ],
+  "spec/support/acceptance_test_helpers.rb:1261310616": [
+    [133, 5, 32, "Style/InvertibleUnlessCondition: Prefer `if $?.exitstatus == 0` over `unless $?.exitstatus != 0`.", 4187517264]
+  ],
+  "spec/support/stream_helpers.rb:3273310040": [
+    [9, 17, 4, "Security/Eval: The use of `eval` is a serious security risk.", 2087429787]
+  ]
+}

.tool-versions

@@ -0,0 +1 @@
+ruby 3.4.2

Gemfile

@@ -2,10 +2,30 @@ source "https://rubygems.org"
 
 gemspec
 
+platform :mri do
+  # Debugging
+  gem "byebug", ">= 11"
+
+  # Dev Console - Binding.pry - Irb replacement
+  gem "pry", "~> 0.14"                     # ruby >= 2.0
+end
+
 # This here to make sure appraisal works with Rails 3.0.0.
 gem "thor", "~> 0.14.0"
 
-group :development, :test do
-  gem "activesupport", ">= 3.2.21"
-  gem "rspec", "~> 3.0"
+# Ruby version specific dependencies
+ruby_version = Gem::Version.new(RUBY_VERSION)
+if ruby_version < Gem::Version.new("1.9")
+  eval File.read("Gemfile-1.8")
+elsif ruby_version < Gem::Version.new("2.1")
+  eval File.read("Gemfile-2.0")
+elsif ruby_version < Gem::Version.new("2.2")
+  eval File.read("Gemfile-2.1")
+elsif ruby_version < Gem::Version.new("2.7")
+  # Std Lib extractions
+  gem "benchmark", "~> 0.4" # Removed from Std Lib in Ruby 3.5
+else
+  # Ruby >= 2.7 we can run style / lint checks via rubocop-gradual with rubocop-lts rules for Ruby 1.8+.
+  # This means we can develop on modern Ruby but remain compatible with ancient Ruby.
+  eval_gemfile "gemfiles/modular/style.gemfile"
 end

Gemfile-1.8

@@ -0,0 +1,6 @@
+# These gems are locked for Ruby 1.8.7 compatibility
+gem "i18n", "~> 0.6.0"
+gem "activesupport", "~> 3.2.21"
+gem "rake", "~> 10.5"
+gem "rack", "~> 1.6.5"
+gem "benchmark", "~> 0.3" # Removed from Std Lib in Ruby 3.5

Gemfile-2.0

@@ -0,0 +1,4 @@
+# These gems are locked for Ruby 1.9 & 2.0 compatibility
+gem "activesupport", "~> 4.2.7"
+gem "rack", "~> 1.6.5"
+gem "benchmark", "~> 0.3" # Removed from Std Lib in Ruby 3.5

Gemfile-2.1

@@ -0,0 +1,4 @@
+# These gems are locked for Ruby 2.1 compatibility
+gem "activesupport", "~> 4.2.7"
+gem "rack", "~> 1.6.5"
+gem "benchmark", "~> 0.4" # Removed from Std Lib in Ruby 3.5

README.md

@@ -110,6 +110,72 @@ When you prefix a command with `appraisal`, the command is run with the
 appropriate Gemfile for that appraisal, ensuring the correct dependencies
 are used.
 
+Sharing Modular Gemfiles between Appraisals
+-------
+
+_New for version 3.0_
+
+It is common for Appraisals to duplicate sets of gems, and sometimes it
+makes sense to DRY this up into a shared, modular, gemfile.
+In a scenario where you do not load your main Gemfile in your Appraisals,
+but you want to declare your various gem sets for e.g.
+`%w(coverage test documentation audit)` once each, you can re-use the same
+modular gemfiles for local development by referencing them from the main
+Gemfile.
+
+To do this, use the `eval_gemfile` declaration within the necessary
+`appraise` block in your `Appraisals` file, which will behave the same as
+`eval_gemfile` does in a normal Gemfile.
+
+### Example Usage
+
+You could put your modular gemfiles in the `gemfiles` directory, or nest
+them in `gemfiles/modular/*`, which will be used for this example.
+
+**Gemfile**
+```ruby
+eval_gemfile "gemfiles/modular/audit.gemfile"
+```
+
+**gemfiles/modular/audit.gemfile**
+```ruby
+# Many gems are dropping support for Ruby < 3.1,
+#   so we only want to run our security audit in CI on Ruby 3.1+
+gem "bundler-audit", "~> 0.9.2"
+# And other security audit gems...
+```
+
+**Appraisals**
+```ruby
+appraise "ruby-2-7" do
+  gem "dummy"
+end
+
+appraise "ruby-3-0" do
+  gem "dummy"
+end
+
+appraise "ruby-3-1" do
+  gem "dummy"
+  eval_gemfile "modular/audit.gemfile"
+end
+
+appraise "ruby-3-2" do
+  gem "dummy"
+  eval_gemfile "modular/audit.gemfile"
+end
+
+appraise "ruby-3-3" do
+  gem "dummy"
+  eval_gemfile "modular/audit.gemfile"
+end
+
+appraise "ruby-3-4" do
+  gem "dummy"
+  eval_gemfile "modular/audit.gemfile"
+end
+```
+
 Removing Gems using Appraisal
 -------
 
@@ -122,31 +188,31 @@ To do this, use the `remove_gem` declaration within the necessary `appraise` blo
 
 **Gemfile**
 ```ruby
-gem 'rails', '~> 4.2'
+gem "rails", "~> 4.2"
 
 group :test do
-  gem 'rspec', '~> 4.0'
-  gem 'test_after_commit'
+  gem "rspec", "~> 4.0"
+  gem "test_after_commit"
 end
 ```
 
 **Appraisals**
 ```ruby
-appraise 'rails-5' do
-  gem 'rails', '~> 5.2'
+appraise "rails-5" do
+  gem "rails", "~> 5.2"
 
   group :test do
-    remove_gem 'test_after_commit'
+    remove_gem "test_after_commit"
   end
 end
 ```
 
 Using the `Appraisals` file defined above, this is what the resulting `Gemfile` will look like:
 ```ruby
-gem 'rails', '~> 5.2'
+gem "rails", "~> 5.2"
 
 group :test do
-  gem 'rspec', '~> 4.0'
+  gem "rspec", "~> 4.0"
 end
 ```
 
@@ -174,12 +240,12 @@ You can also provide variables for substitution in the heading, based on each ap
 ```ruby
 customize_gemfiles do
   {
-    single_quotes: true,
-    heading: <<~HEADING
-      frozen_string_literal: true
+    :single_quotes => true,
+    :heading => <<-HEADING,
+frozen_string_literal: true
 
-      `%{gemfile}` has been generated by Appraisal, do NOT modify it or `%{lockfile}` directly!
-      Make the changes to the "%{appraisal}" block in `Appraisals` instead. See the conventions at https://example.com/
+`%{gemfile}` has been generated by Appraisal, do NOT modify it or `%{lockfile}` directly!
+Make the changes to the "%{appraisal}" block in `Appraisals` instead. See the conventions at https://example.com/
     HEADING
   }
 end
@@ -196,7 +262,7 @@ Using the `Appraisals` file defined above, this is what the resulting `Gemfile`
 # `rails-3.gemfile` has been generated by Appraisal, do NOT modify it or `rails-3.gemfile.lock` directly!
 # Make the changes to the "rails-3" block in `Appraisals` instead. See the conventions at https://example.com/
 
-gem 'rails', '3.2.14'
+gem "rails", "3.2.14"
 ```
 
 Version Control

Rakefile

@@ -10,5 +10,14 @@ RSpec::Core::RakeTask.new do |t|
   t.verbose = false
 end
 
-desc "Default: run the rspec examples"
-task default: [:spec]
+begin
+  require "rubocop/lts"
+  Rubocop::Lts.install_tasks
+rescue LoadError
+  task(:rubocop_gradual) do
+    warn("RuboCop (Gradual) is disabled")
+  end
+end
+
+desc "Default: rubocop_gradual's autocorrect and run the rspec examples"
+task :default => ["rubocop_gradual:autocorrect", :spec]