Add bundler-cache feature in dev container

railties/lib/rails/generators/rails/devcontainer/templates/devcontainer/compose.yaml.tt

@@ -8,6 +8,7 @@ services:
 
     volumes:
     - ../..:/workspaces:cached
+    - rbenv-data:/home/vscode/.rbenv
 
     # Overrides default command so things don't shut down after the process ends.
     command: sleep infinity
@@ -39,8 +40,10 @@ services:
 
 <%- end -%>
   <%= devcontainer_db_service_yaml(indentation: 4) %>
-<%- if !volumes.empty? -%>
+
 volumes:
+  rbenv-data:
+<%- if !volumes.empty? -%>
 <%- volumes.each do |volume| -%>
   <%= volume %>:
 <%- end -%>

railties/test/generators/devcontainer_generator_test.rb

@@ -59,6 +59,19 @@ def test_app_name_option
         end
       end
 
+      def test_app_volumes
+        run_generator
+
+        assert_compose_file do |compose|
+          expected_volumes = ["../..:/workspaces:cached", "rbenv-data:/home/vscode/.rbenv"]
+          actual_volumes = compose["services"]["rails-app"]["volumes"]
+          expected_volumes.each do |volume|
+            assert_includes actual_volumes, volume
+          end
+          assert_equal ["rbenv-data", "redis-data"], compose["volumes"].keys
+        end
+      end
+
       def test_database_default_sqlite3
         run_generator
 
@@ -84,7 +97,7 @@ def test_database_mariadb_mysql
             },
           }
           assert_equal expected_mariadb_config, compose["services"]["mariadb"]
-          assert_includes compose["volumes"].keys, "mariadb-data"
+          assert_equal ["rbenv-data", "redis-data", "mariadb-data"], compose["volumes"].keys
           assert_includes compose["services"]["rails-app"]["depends_on"], "mariadb"
         end
 
@@ -111,7 +124,7 @@ def test_database_mariadb_trilogy
             },
           }
           assert_equal expected_mariadb_config, compose["services"]["mariadb"]
-          assert_includes compose["volumes"].keys, "mariadb-data"
+          assert_equal ["rbenv-data", "redis-data", "mariadb-data"], compose["volumes"].keys
           assert_includes compose["services"]["rails-app"]["depends_on"], "mariadb"
         end
 
@@ -138,7 +151,7 @@ def test_database_mysql
             "networks" => ["default"],
           }
           assert_equal expected_mysql_config, compose["services"]["mysql"]
-          assert_includes compose["volumes"].keys, "mysql-data"
+          assert_equal ["rbenv-data", "redis-data", "mysql-data"], compose["volumes"].keys
           assert_includes compose["services"]["rails-app"]["depends_on"], "mysql"
         end
 
@@ -172,7 +185,7 @@ def test_database_postgresql
             }
           }
           assert_equal expected_postgres_config, compose["services"]["postgres"]
-          assert_includes compose["volumes"].keys, "postgres-data"
+          assert_equal ["rbenv-data", "redis-data", "postgres-data"], compose["volumes"].keys
           assert_includes compose["services"]["rails-app"]["depends_on"], "postgres"
         end
 
@@ -200,7 +213,7 @@ def test_database_trilogy
             "networks" => ["default"],
           }
           assert_equal expected_mysql_config, compose["services"]["mysql"]
-          assert_includes compose["volumes"].keys, "mysql-data"
+          assert_equal ["rbenv-data", "redis-data", "mysql-data"], compose["volumes"].keys
           assert_includes compose["services"]["rails-app"]["depends_on"], "mysql"
         end
 
@@ -259,7 +272,7 @@ def test_redis_option_default
             "volumes" => ["redis-data:/data"]
           }
           assert_equal expected_redis_config, compose["services"]["redis"]
-          assert_equal ["redis-data"], compose["volumes"].keys
+          assert_equal ["rbenv-data", "redis-data"], compose["volumes"].keys
         end
 
         assert_devcontainer_json_file do |devcontainer_json|
@@ -275,7 +288,7 @@ def test_redis_option_skip
         assert_compose_file do |compose|
           assert_not_includes compose["services"]["rails-app"]["depends_on"], "redis"
           assert_nil compose["services"]["redis"]
-          assert_nil compose["volumes"]
+          assert_equal ["rbenv-data"], compose["volumes"].keys
         end
 
         assert_devcontainer_json_file do |devcontainer_json|
@@ -341,7 +354,7 @@ def test_common_config
                 "context" => "..",
                 "dockerfile" => ".devcontainer/Dockerfile"
               },
-              "volumes" => ["../..:/workspaces:cached"],
+              "volumes" => ["../..:/workspaces:cached", "rbenv-data:/home/vscode/.rbenv"],
               "command" => "sleep infinity"
             }
             actual_independent_config = compose["services"]["rails-app"].except("depends_on")