Fix crash in pub grub involving empty ranges

bundler/lib/bundler/vendor/pub_grub/lib/pub_grub/version_range.rb

@@ -19,7 +19,7 @@ def empty?
         true
       end
 
-      def eql?
+      def eql?(other)
         other.empty?
       end
 

bundler/spec/commands/lock_spec.rb

@@ -644,6 +644,62 @@ def read_lockfile(file = "Gemfile.lock")
     bundle "lock --add-platform x86_64-linux", :artifice => "compact_index", :env => { "BUNDLER_SPEC_GEM_REPO" => gem_repo4.to_s }
   end
 
+  it "does not crash on conflicting ruby requirements between platform versions in two different gems" do
+    build_repo4 do
+      build_gem "unf_ext", "0.0.8.2"
+
+      build_gem "unf_ext", "0.0.8.2" do |s|
+        s.required_ruby_version = [">= 2.4", "< #{previous_ruby_minor}"]
+        s.platform = "x64-mingw32"
+      end
+
+      build_gem "unf_ext", "0.0.8.2" do |s|
+        s.required_ruby_version = [">= #{previous_ruby_minor}", "< #{current_ruby_minor}"]
+        s.platform = "x64-mingw-ucrt"
+      end
+
+      build_gem "google-protobuf", "3.21.12"
+
+      build_gem "google-protobuf", "3.21.12" do |s|
+        s.required_ruby_version = [">= 2.5", "< #{previous_ruby_minor}"]
+        s.platform = "x64-mingw32"
+      end
+
+      build_gem "google-protobuf", "3.21.12" do |s|
+        s.required_ruby_version = [">= #{previous_ruby_minor}", "< #{current_ruby_minor}"]
+        s.platform = "x64-mingw-ucrt"
+      end
+    end
+
+    gemfile <<~G
+      source "https://gem.repo4"
+
+      gem "google-protobuf"
+      gem "unf_ext"
+    G
+
+    lockfile <<~L
+      GEM
+        remote: https://gem.repo4/
+        specs:
+          google-protobuf (3.21.12)
+          unf_ext (0.0.8.2)
+
+      PLATFORMS
+        x64-mingw-ucrt
+        x64-mingw32
+
+      DEPENDENCIES
+        google-protobuf
+        unf_ext
+
+      BUNDLED WITH
+         #{Bundler::VERSION}
+    L
+
+    bundle "install --verbose", :artifice => "compact_index", :env => { "BUNDLER_SPEC_GEM_REPO" => gem_repo4.to_s, "DEBUG_RESOLVER" => "1" }
+  end
+
   it "respects lower bound ruby requirements" do
     build_repo4 do
       build_gem "our_private_gem", "0.1.0" do |s|

bundler/spec/support/helpers.rb

@@ -483,7 +483,17 @@ def current_ruby_minor
     end
 
     def next_ruby_minor
-      Gem.ruby_version.segments[0..1].map.with_index {|s, i| i == 1 ? s + 1 : s }.join(".")
+      ruby_major_minor.map.with_index {|s, i| i == 1 ? s + 1 : s }.join(".")
+    end
+
+    def previous_ruby_minor
+      return "2.7" if ruby_major_minor == [3, 0]
+
+      ruby_major_minor.map.with_index {|s, i| i == 1 ? s - 1 : s }.join(".")
+    end
+
+    def ruby_major_minor
+      Gem.ruby_version.segments[0..1]
     end
 
     # versions not including