From 3122d59302b7820704ca5f7622bea2900bcf7d63 Mon Sep 17 00:00:00 2001
From: Vinicius Stock <vinicius.stock@shopify.com>
Date: Thu, 12 Dec 2024 13:34:01 -0500
Subject: [PATCH] Fix debug platform inclusion for Windows

---
 lib/ruby_lsp/setup_bundler.rb |  8 +++++++-
 test/setup_bundler_test.rb    | 33 +++++++++++++++++++++++++++++++++
 2 files changed, 40 insertions(+), 1 deletion(-)

diff --git a/lib/ruby_lsp/setup_bundler.rb b/lib/ruby_lsp/setup_bundler.rb
index 45c4b59ce..1fc7ce891 100644
--- a/lib/ruby_lsp/setup_bundler.rb
+++ b/lib/ruby_lsp/setup_bundler.rb
@@ -152,7 +152,13 @@ def write_custom_gemfile
       end
 
       unless @dependencies["debug"]
-        parts << 'gem "debug", require: false, group: :development, platforms: :mri'
+        # The `mri` platform excludes Windows. We want to install the debug gem only on MRI for any operating system,
+        # but that constraint doesn't yet exist in Bundler. On Windows, we are manually checking if the engine is MRI
+        parts << if Gem.win_platform?
+          'gem "debug", require: false, group: :development, install_if: -> { RUBY_ENGINE == "ruby" }'
+        else
+          'gem "debug", require: false, group: :development, platforms: :mri'
+        end
       end
 
       if @rails_app && !@dependencies["ruby-lsp-rails"]
diff --git a/test/setup_bundler_test.rb b/test/setup_bundler_test.rb
index b7cb8980f..6b02b8299 100644
--- a/test/setup_bundler_test.rb
+++ b/test/setup_bundler_test.rb
@@ -823,6 +823,39 @@ def test_is_resilient_to_gemfile_changes_in_the_middle_of_setup
     end
   end
 
+  def test_composed_bundle_includes_debug
+    Dir.mktmpdir do |dir|
+      Dir.chdir(dir) do
+        File.write(File.join(dir, "Gemfile"), <<~GEMFILE)
+          source "https://rubygems.org"
+        GEMFILE
+
+        env = T.let({}, T::Hash[String, T.untyped])
+
+        Bundler.with_unbundled_env do
+          env = ENV.to_hash
+
+          capture_subprocess_io do
+            system("bundle install")
+            assert_path_exists("Gemfile.lock")
+
+            new_env = RubyLsp::SetupBundler.new(dir, launcher: true).setup!
+            env["BUNDLE_GEMFILE"] = new_env["BUNDLE_GEMFILE"]
+            env["BUNDLE_PATH"] = new_env["BUNDLE_PATH"] if new_env["BUNDLE_PATH"]
+          end
+        end
+
+        Bundler.with_unbundled_env do
+          _stdout, stderr = capture_subprocess_io do
+            system(env, "bundle exec ruby -e 'require \"debug\"'")
+          end
+
+          assert_empty(stderr)
+        end
+      end
+    end
+  end
+
   private
 
   def with_default_external_encoding(encoding, &block)