[rubygems/rubygems] Materializing specs for vendor/cache should not be strict

Platforms specific gems not compatible with the current Ruby should not
make `bundle cache` fail and should not get removed from the cache since
they still may be useful in other rubies.

717b43f565

lib/bundler/lazy_specification.rb

@@ -124,7 +124,7 @@ module Bundler
     def materialize_for_cache
       source.remote!
 
-      materialize_strictly
+      materialize(self, &:first)
     end
 
     def materialized_for_installation
@@ -137,7 +137,9 @@ module Bundler
       source.local!
 
       if use_exact_resolved_specifications?
-        materialize_strictly
+        materialize(self) do |matching_specs|
+          choose_compatible(matching_specs)
+        end
       else
         materialize([name, version]) do |matching_specs|
           target_platform = source.is_a?(Source::Path) ? platform : local_platform
@@ -185,12 +187,6 @@ module Bundler
       (most_specific_locked_platform != generic_platform) || force_ruby_platform || Bundler.settings[:force_ruby_platform]
     end
 
-    def materialize_strictly
-      materialize(self) do |matching_specs|
-        choose_compatible(matching_specs)
-      end
-    end
-
     def materialize(query)
       matching_specs = source.specs.search(query)
       return self if matching_specs.empty?

spec/bundler/commands/cache_spec.rb

@@ -482,6 +482,53 @@ RSpec.describe "bundle install with gem sources" do
       expect(the_bundle).to include_gems("platform_specific 1.0 ruby")
     end
 
+    it "keeps gems that are locked and cached for the current platform, even if incompatible with the current ruby" do
+      build_repo4 do
+        build_gem "bcrypt_pbkdf", "1.1.1"
+        build_gem "bcrypt_pbkdf", "1.1.1" do |s|
+          s.platform = "arm64-darwin"
+          s.required_ruby_version = "< #{current_ruby_minor}"
+        end
+      end
+
+      app_cache = bundled_app("vendor/cache")
+      FileUtils.mkdir_p app_cache
+      FileUtils.cp gem_repo4("gems/bcrypt_pbkdf-1.1.1-arm64-darwin.gem"), app_cache
+      FileUtils.cp gem_repo4("gems/bcrypt_pbkdf-1.1.1.gem"), app_cache
+
+      bundle "config cache_all_platforms true"
+
+      lockfile <<~L
+        GEM
+          remote: https://gem.repo4/
+          specs:
+            bcrypt_pbkdf (1.1.1)
+            bcrypt_pbkdf (1.1.1-arm64-darwin)
+
+        PLATFORMS
+          arm64-darwin
+          ruby
+
+        DEPENDENCIES
+          bcrypt_pbkdf
+
+        BUNDLED WITH
+           #{Bundler::VERSION}
+      L
+
+      simulate_platform "arm64-darwin-23" do
+        install_gemfile <<~G, verbose: true
+          source "https://gem.repo4"
+          gem "bcrypt_pbkdf"
+        G
+
+        expect(out).to include("Updating files in vendor/cache")
+        expect(err).to be_empty
+        expect(app_cache.join("bcrypt_pbkdf-1.1.1-arm64-darwin.gem")).to exist
+        expect(app_cache.join("bcrypt_pbkdf-1.1.1.gem")).to exist
+      end
+    end
+
     it "does not update the cache if --no-cache is passed" do
       gemfile <<-G
         source "https://gem.repo1"