Handle Errno::EPERM errors when composing bundle

Some of these errors have been reported to our telemetry. For now, it makes
sense to rescue the error and ignore it because it means that the user's
environment does not have permissions to read their lockfile, which means
we can't compose the bundle.

Author: egiurleo

lib/ruby_lsp/server.rb

@@ -1388,6 +1388,9 @@ def compose_bundle(message)
       rescue Bundler::LockfileError => e
         send_message(Error.new(id: id, code: BUNDLE_COMPOSE_FAILED_CODE, message: e.message))
         return
+      rescue Errno::EPERM
+        # If the user doesn't have permission to perform read operations, we can't compose the bundle
+        return
       rescue Bundler::GemfileNotFound, Errno::ENOENT
         # We still compose the bundle if there's no Gemfile or if the lockfile got deleted
       end

test/server_test.rb

@@ -1214,6 +1214,36 @@ def test_compose_bundle_does_not_fail_if_restarting_on_lockfile_deletion
     end
   end
 
+  def test_compose_bundle_does_not_fail_if_user_does_not_have_permission_to_read_lockfile
+    Dir.mktmpdir do |dir|
+      Dir.chdir(dir) do
+        @server.process_message({
+          id: 1,
+          method: "initialize",
+          params: {
+            initializationOptions: {},
+            capabilities: { general: { positionEncodings: ["utf-8"] } },
+            workspaceFolders: [{ uri: URI::Generic.from_path(path: dir).to_s }],
+          },
+        })
+
+        File.write(File.join(dir, "Gemfile"), <<~GEMFILE)
+          source "https://rubygems.org"
+          gem "stringio"
+        GEMFILE
+
+        system("chmod 0000", Bundler.default_lockfile.to_s)
+
+        capture_subprocess_io do
+          @server.send(:compose_bundle, { id: 2, method: "rubyLsp/composeBundle" })&.join
+        end
+
+        result = find_message(RubyLsp::Result, id: 2)
+        assert(result.response[:success])
+      end
+    end
+  end
+
   def test_does_not_index_on_did_change_watched_files_if_document_is_managed_by_client
     path = File.join(Dir.pwd, "lib", "foo.rb")
     source = <<~RUBY