Add node and yarn to devcontainer when creating a project with Javascript

Author: duduribeiro

railties/lib/rails/generators/devcontainer.rb

@@ -47,6 +47,8 @@ def devcontainer_features
           }
 
           @devcontainer_features["ghcr.io/rails/devcontainer/features/activestorage"] = {} unless options[:skip_active_storage]
+          @devcontainer_features["ghcr.io/devcontainers/features/node:1"] = {} if using_node?
+
           @devcontainer_features.merge!(db_feature_for_devcontainer) if db_feature_for_devcontainer
 
           @devcontainer_features

railties/lib/rails/generators/rails/app/templates/.devcontainer/devcontainer.json.tt

@@ -8,7 +8,7 @@
 
   // Features to add to the dev container. More info: https://containers.dev/features.
   "features": {
-    <%= devcontainer_features.map { |key, value| "\"#{key}\": #{value}" }.join(",\n    ") %>
+    <%= devcontainer_features.map { |key, value| "\"#{key}\": #{value.as_json}" }.join(",\n    ") %>
   },
 
 <%- if !devcontainer_variables.empty? -%>

railties/test/generators/app_generator_test.rb

@@ -1409,6 +1409,22 @@ def test_devcontainer_no_depends_on_when_no_dependencies
     end
   end
 
+  def test_devcontainer_adds_node_tooling_when_required
+    run_generator [destination_root, "--javascript=esbuild"]
+
+    assert_devcontainer_json_file do |devcontainer_config|
+      assert_includes devcontainer_config["features"].keys, "ghcr.io/devcontainers/features/node:1"
+    end
+  end
+
+  def test_devcontainer_does_not_add_node_tooling_when_not_required
+    run_generator [destination_root]
+
+    assert_devcontainer_json_file do |devcontainer_config|
+      assert_not_includes devcontainer_config["features"].keys, "ghcr.io/devcontainers/features/node:1"
+    end
+  end
+
   def test_devcontainer_dev_flag_mounts_local_rails_repo
     run_generator_using_prerelease [ destination_root, "--dev" ]