[rubygems/rubygems] Don't remove platform specific variants from the lockfile unless necessary

Even if they don't match the current Ruby version, they could still work
in other rubies. So it's better to keep them.

https://github.com/rubygems/rubygems/commit/9a3e583b0c

4 files changed, 15 insertions, 3 deletions

diff --git a/lib/bundler/definition.rb b/lib/bundler/definition.rb
index fd81fe2aa3..c31682ce4e 100644
--- a/lib/bundler/definition.rb
+++ b/lib/bundler/definition.rb
@@ -742,7 +742,7 @@ module Bundler
 
       @platforms = result.add_extra_platforms!(platforms) if should_add_extra_platforms?
 
-      SpecSet.new(result.for(dependencies, @platforms))
+      SpecSet.new(result.for(dependencies, @platforms | [Gem::Platform::RUBY]))
     end
 
     def precompute_source_requirements_for_indirect_dependencies?
diff --git a/lib/bundler/resolver.rb b/lib/bundler/resolver.rb
index 54e25a2adc..56a6c7ac67 100644
--- a/lib/bundler/resolver.rb
+++ b/lib/bundler/resolver.rb
@@ -80,7 +80,8 @@ module Bundler
     def solve_versions(root:, logger:)
       solver = PubGrub::VersionSolver.new(source: self, root: root, logger: logger)
       result = solver.solve
-      result.flat_map {|package, version| version.to_specs(package, @most_specific_locked_platform) }
+      resolved_specs = result.flat_map {|package, version| version.to_specs(package, @most_specific_locked_platform) }
+      SpecSet.new(resolved_specs).specs_with_additional_variants_from(@base.locked_specs)
     rescue PubGrub::SolveFailure => e
       incompatibility = e.incompatibility
 
diff --git a/lib/bundler/resolver/base.rb b/lib/bundler/resolver/base.rb
index f7d15a3024..932a92ff41 100644
--- a/lib/bundler/resolver/base.rb
+++ b/lib/bundler/resolver/base.rb
@@ -5,10 +5,11 @@ require_relative "package"
 module Bundler
   class Resolver
     class Base
-      attr_reader :packages, :requirements, :source_requirements
+      attr_reader :packages, :requirements, :source_requirements, :locked_specs
 
       def initialize(source_requirements, dependencies, base, platforms, options)
         @source_requirements = source_requirements
+        @locked_specs = options[:locked_specs]
 
         @base = base
 
diff --git a/lib/bundler/spec_set.rb b/lib/bundler/spec_set.rb
index 994c3d29d2..f0082d46d5 100644
--- a/lib/bundler/spec_set.rb
+++ b/lib/bundler/spec_set.rb
@@ -163,6 +163,10 @@ module Bundler
       @specs.detect {|spec| spec.name == name && spec.match_platform(platform) }
     end
 
+    def specs_with_additional_variants_from(other)
+      sorted | additional_variants_from(other)
+    end
+
     def delete_by_name(name)
       @specs.reject! {|spec| spec.name == name }
 
@@ -277,6 +281,12 @@ module Bundler
       @specs.flat_map {|spec| spec.source.specs.search([spec.name, spec.version]).map(&:platform) }.uniq
     end
 
+    def additional_variants_from(other)
+      other.select do |spec|
+        version_for(spec.name) == spec.version && valid_dependencies?(spec)
+      end
+    end
+
     def valid_dependencies?(s)
       validate_deps(s) == :valid
     end