allow compatibility with Ruby 2.6

.github/workflows/ci.yml

@@ -13,13 +13,16 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        ruby-version: [2.7, "3.0", 3.1, 3.2]
+        ruby-version: [2.6, 2.7, "3.0", 3.1, 3.2]
         bundler-version: [2.4.20, 2.5.2]
         exclude:
+          - ruby-version: 2.6
+            bundler-version: 2.5.2
           - ruby-version: 2.7
             bundler-version: 2.5.2
     env:
       BUNDLER_VERSION: ${{ matrix.bundler-version }}
+      BUNDLE_LOCKFILE: active
     steps:
       - uses: actions/checkout@v3
       - name: Set up Ruby

.gitignore

@@ -1,2 +1,3 @@
 /*.gem
-/pkg
+/.bundle/
+/pkg/

.rubocop.yml

@@ -7,7 +7,10 @@ require:
   - rubocop-rake
 
 AllCops:
-  TargetRubyVersion: 2.7
+  TargetRubyVersion: 2.6
+
+Bundler/DuplicatedGem:
+  Enabled: false
 
 Naming/FileName:
   Exclude:

Gemfile

@@ -6,3 +6,22 @@ source "https://rubygems.org"
 # Bundler will treat runtime dependencies like base dependencies, and
 # development dependencies will be added by default to the :development group.
 gemspec
+
+plugin "bundler-multilock", path: "."
+return unless Plugin.installed?("bundler-multilock")
+
+Plugin.send(:load_plugin, "bundler-multilock")
+
+lockfile active: RUBY_VERSION >= "2.7" do
+  gem "debug", "~> 1.9", require: false
+  gem "rubocop-inst", "~> 1.0"
+  gem "rubocop-rake", "~> 0.6"
+  gem "rubocop-rspec", "~> 2.24"
+  gem "stringio", "~> 3.1", require: false
+end
+
+lockfile "ruby-2.6", active: RUBY_VERSION < "2.7" do
+  # newer versions of these gems are not compatible with Ruby > 2.6
+  gem "debug", "1.8.0", require: false
+  gem "stringio", "3.0.6", require: false
+end

Gemfile.lock

@@ -9,12 +9,12 @@ GEM
   specs:
     ast (2.4.2)
     base64 (0.1.1)
-    debug (1.8.0)
-      irb (>= 1.5.0)
-      reline (>= 0.3.1)
+    debug (1.9.0)
+      irb (~> 1.10)
+      reline (>= 0.3.8)
     diff-lcs (1.5.0)
-    io-console (0.6.0)
-    irb (1.8.1)
+    io-console (0.7.1)
+    irb (1.11.0)
       rdoc
       reline (>= 0.3.8)
     json (2.6.3)
@@ -23,15 +23,15 @@ GEM
     parser (3.2.2.3)
       ast (~> 2.4.1)
       racc
-    psych (5.1.0)
+    psych (5.1.2)
       stringio
     racc (1.7.1)
     rainbow (3.1.1)
     rake (13.0.6)
-    rdoc (6.5.0)
+    rdoc (6.6.2)
       psych (>= 4.0.0)
     regexp_parser (2.8.1)
-    reline (0.3.8)
+    reline (0.4.1)
       io-console (~> 0.5)
     rexml (3.2.6)
     rspec (3.12.0)
@@ -78,7 +78,7 @@ GEM
       rubocop-capybara (~> 2.17)
       rubocop-factory_bot (~> 2.22)
     ruby-progressbar (1.13.0)
-    stringio (3.0.8)
+    stringio (3.1.0)
     unicode-display_width (2.4.2)
 
 PLATFORMS
@@ -90,12 +90,13 @@ PLATFORMS
 
 DEPENDENCIES
   bundler-multilock!
-  debug (~> 1.8)
+  debug (~> 1.9)
   rake (~> 13.0)
   rspec (~> 3.12)
   rubocop-inst (~> 1.0)
   rubocop-rake (~> 0.6)
   rubocop-rspec (~> 2.24)
+  stringio (~> 3.1)
 
 BUNDLED WITH
    2.5.2

Gemfile.ruby-2.6.lock

@@ -0,0 +1,55 @@
+PATH
+  remote: .
+  specs:
+    bundler-multilock (1.2.1)
+      bundler (>= 2.4.19, < 2.6)
+
+GEM
+  remote: https://rubygems.org/
+  specs:
+    debug (1.8.0)
+      irb (>= 1.5.0)
+      reline (>= 0.3.1)
+    diff-lcs (1.5.0)
+    io-console (0.7.1)
+    irb (1.11.0)
+      rdoc
+      reline (>= 0.3.8)
+    psych (5.1.2)
+      stringio
+    rake (13.0.6)
+    rdoc (6.6.2)
+      psych (>= 4.0.0)
+    reline (0.4.1)
+      io-console (~> 0.5)
+    rspec (3.12.0)
+      rspec-core (~> 3.12.0)
+      rspec-expectations (~> 3.12.0)
+      rspec-mocks (~> 3.12.0)
+    rspec-core (3.12.2)
+      rspec-support (~> 3.12.0)
+    rspec-expectations (3.12.3)
+      diff-lcs (>= 1.2.0, < 2.0)
+      rspec-support (~> 3.12.0)
+    rspec-mocks (3.12.6)
+      diff-lcs (>= 1.2.0, < 2.0)
+      rspec-support (~> 3.12.0)
+    rspec-support (3.12.1)
+    stringio (3.0.6)
+
+PLATFORMS
+  aarch64-linux
+  arm64-darwin
+  ruby
+  x86_64-darwin
+  x86_64-linux
+
+DEPENDENCIES
+  bundler-multilock!
+  debug (= 1.8.0)
+  rake (~> 13.0)
+  rspec (~> 3.12)
+  stringio (= 3.0.6)
+
+BUNDLED WITH
+   2.5.2

bundler-multilock.gemspec

@@ -14,14 +14,10 @@ Gem::Specification.new do |spec|
   spec.files         = Dir.glob("lib/**/*") + %w[plugins.rb]
   spec.require_paths = ["lib"]
 
-  spec.required_ruby_version = ">= 2.7"
+  spec.required_ruby_version = ">= 2.6"
 
   spec.add_dependency "bundler", ">= 2.4.19", "< 2.6"
 
-  spec.add_development_dependency "debug", "~> 1.8"
   spec.add_development_dependency "rake", "~> 13.0"
   spec.add_development_dependency "rspec", "~> 3.12"
-  spec.add_development_dependency "rubocop-inst", "~> 1.0"
-  spec.add_development_dependency "rubocop-rake", "~> 0.6"
-  spec.add_development_dependency "rubocop-rspec", "~> 2.24"
 end

lib/bundler/multilock/ext/plugin/dsl.rb

@@ -7,7 +7,7 @@ module PluginExt
         module DSL
           ::Bundler::Plugin::DSL.include(self)
 
-          def lockfile(...)
+          def lockfile(*, **)
             # pass
           end
         end

lib/bundler/multilock/ext/source.rb

@@ -6,7 +6,7 @@ module Ext
       module Source
         ::Bundler::Source.prepend(self)
 
-        def print_using_message(...)
+        def print_using_message(*)
           return if Bundler.settings[:suppress_install_using_messages]
 
           super