From 98c84ef42c61b84c1745bbc5a1ceff1ce00999d9 Mon Sep 17 00:00:00 2001
From: Mike Dalessio <mike.dalessio@gmail.com>
Date: Mon, 15 Apr 2024 13:17:54 -0400
Subject: [PATCH] [rubygems/rubygems] Excluding local platform from lockfile
 should not affect musl vs gnu case

This case is for not locking things like `arm-darwin-23` when the
lockfile already includes `arm-darwin`, so that we don't infinitely keep
redundant versioned platforms in the lockfile when not necessary.

We detect this with `Gem::Platform#===`. For example,
`Gem::Platform.new("arm-darwin-23") === Gem::Platform.new("arm-darwin")`
but they're not `==`.

However, in the case of `-musl` vs `-gnu`, those act as the platform
"version", but `===` is not commutative for them. This is explained in
`===` docs.

We only want to exclude the local platform in situations when
`Gem::Platform#===` is actually commutative.

https://github.com/rubygems/rubygems/commit/8099c4face
---
 lib/bundler/spec_set.rb                       |  2 +-
 .../install/gemfile/specific_platform_spec.rb | 76 ++++++++++---------
 2 files changed, 41 insertions(+), 37 deletions(-)

diff --git a/lib/bundler/spec_set.rb b/lib/bundler/spec_set.rb
index 96e1403bf7..2933d28450 100644
--- a/lib/bundler/spec_set.rb
+++ b/lib/bundler/spec_set.rb
@@ -65,7 +65,7 @@ module Bundler
 
       platforms.concat(new_platforms)
 
-      less_specific_platform = new_platforms.find {|platform| platform != Gem::Platform::RUBY && Bundler.local_platform === platform }
+      less_specific_platform = new_platforms.find {|platform| platform != Gem::Platform::RUBY && Bundler.local_platform === platform && platform === Bundler.local_platform }
       platforms.delete(Bundler.local_platform) if less_specific_platform
 
       platforms
diff --git a/spec/bundler/install/gemfile/specific_platform_spec.rb b/spec/bundler/install/gemfile/specific_platform_spec.rb
index c81c7095b0..5f1b034bfc 100644
--- a/spec/bundler/install/gemfile/specific_platform_spec.rb
+++ b/spec/bundler/install/gemfile/specific_platform_spec.rb
@@ -1262,43 +1262,47 @@ RSpec.describe "bundle install with specific platforms" do
     end
   end
 
-  it "adds current musl platform" do
-    build_repo4 do
-      build_gem "rcee_precompiled", "0.5.0" do |s|
-        s.platform = "x86_64-linux"
+  ["x86_64-linux", "x86_64-linux-musl"].each do |host_platform|
+    describe "on host platform #{host_platform}" do
+      it "adds current musl platform" do
+        build_repo4 do
+          build_gem "rcee_precompiled", "0.5.0" do |s|
+            s.platform = "x86_64-linux"
+          end
+
+          build_gem "rcee_precompiled", "0.5.0" do |s|
+            s.platform = "x86_64-linux-musl"
+          end
+        end
+
+        gemfile <<~G
+          source "#{file_uri_for(gem_repo4)}"
+
+          gem "rcee_precompiled", "0.5.0"
+        G
+
+        simulate_platform host_platform do
+          bundle "lock", artifice: "compact_index", env: { "BUNDLER_SPEC_GEM_REPO" => gem_repo4.to_s }
+
+          expect(lockfile).to eq(<<~L)
+            GEM
+              remote: #{file_uri_for(gem_repo4)}/
+              specs:
+                rcee_precompiled (0.5.0-x86_64-linux)
+                rcee_precompiled (0.5.0-x86_64-linux-musl)
+
+            PLATFORMS
+              x86_64-linux
+              x86_64-linux-musl
+
+            DEPENDENCIES
+              rcee_precompiled (= 0.5.0)
+
+            BUNDLED WITH
+               #{Bundler::VERSION}
+          L
+        end
       end
-
-      build_gem "rcee_precompiled", "0.5.0" do |s|
-        s.platform = "x86_64-linux-musl"
-      end
-    end
-
-    gemfile <<~G
-      source "#{file_uri_for(gem_repo4)}"
-
-      gem "rcee_precompiled", "0.5.0"
-    G
-
-    simulate_platform "x86_64-linux-musl" do
-      bundle "lock", artifice: "compact_index", env: { "BUNDLER_SPEC_GEM_REPO" => gem_repo4.to_s }
-
-      expect(lockfile).to eq(<<~L)
-        GEM
-          remote: #{file_uri_for(gem_repo4)}/
-          specs:
-            rcee_precompiled (0.5.0-x86_64-linux)
-            rcee_precompiled (0.5.0-x86_64-linux-musl)
-
-        PLATFORMS
-          x86_64-linux
-          x86_64-linux-musl
-
-        DEPENDENCIES
-          rcee_precompiled (= 0.5.0)
-
-        BUNDLED WITH
-           #{Bundler::VERSION}
-      L
     end
   end