Upgrade React on Rails from 14.2.1 to 16.0.1.rc.2

- Update react_on_rails gem: 14.2.1 → 16.0.1.rc.2
- Update react-on-rails npm: 14.2.1 → 16.0.1-rc.2
- Update rescript-react-on-rails: 1.0.1 → 1.1.0 (for React on Rails 16 support)
- Add test environment configuration to resolve server bundle path issue
- Add .prettierignore rule for ReScript generated files
- All 38 tests passing ✅

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

Author: justin808

.prettierignore

@@ -7,3 +7,6 @@ spec/support/
 client/app/libs/i18n/translations.js
 client/app/libs/i18n/default.js
 vendor/bundle
+
+# ReScript generated files should not be formatted
+**/*.bs.js

Gemfile

@@ -5,7 +5,7 @@ git_source(:github) { |repo| "https://github.com/#{repo}.git" }
 
 ruby "3.3.4"
 
-gem "react_on_rails", "14.2.1"
+gem "react_on_rails", "16.0.1.rc.2"
 gem "shakapacker", "8.0.0"
 
 # Bundle edge Rails instead: gem "rails", github: "rails/rails"

Gemfile.lock

@@ -297,12 +297,13 @@ GEM
     rdoc (6.14.2)
       erb
       psych (>= 4.0.0)
-    react_on_rails (14.2.1)
+    react_on_rails (16.0.1.rc.2)
       addressable
       connection_pool
       execjs (~> 2.5)
       rails (>= 5.2)
       rainbow (~> 3.0)
+      shakapacker (>= 6.0)
     redcarpet (3.6.0)
     redis (5.3.0)
       redis-client (>= 0.22.0)
@@ -481,7 +482,7 @@ DEPENDENCIES
   rails-html-sanitizer
   rails_best_practices
   rainbow
-  react_on_rails (= 14.2.1)
+  react_on_rails (= 16.0.1.rc.2)
   redcarpet
   redis (~> 5.0)
   rspec-rails (~> 6.0.0)

config/initializers/react_on_rails.rb

@@ -14,6 +14,16 @@
   # not affect performance.
   config.server_bundle_js_file = "server-bundle.js"
 
+  # React on Rails 16 compatibility: Workaround for removed error handling
+  #
+  # BREAKING CHANGE in v16: React on Rails 14.2.1 had robust error handling that would
+  # fallback to the Shakapacker output path when bundle lookup failed. This was removed
+  # in v16.0.1.rc.2, causing it to look in the wrong directory during tests.
+  #
+  # This configuration tells React on Rails where to find bundles in test environment.
+  # Without this, it defaults to public/webpack/test/ instead of public/packs/
+  config.generated_assets_dir = Rails.public_path.join("packs").to_s if Rails.env.test?
+
   ################################################################################
   # CLIENT RENDERING OPTIONS
   # Below options can be overriden by passing options to the react_on_rails

package.json

@@ -78,7 +78,7 @@
     "react": "^19.0.0",
     "react-dom": "^19.0.0",
     "react-intl": "^6.4.4",
-    "react-on-rails": "14.2.1",
+    "react-on-rails": "16.0.1-rc.2",
     "react-redux": "^8.1.0",
     "react-router": "^6.13.0",
     "react-router-dom": "^6.13.0",
@@ -87,7 +87,7 @@
     "redux": "^4.2.1",
     "redux-thunk": "^2.2.0",
     "rescript": "^11.1.4",
-    "rescript-react-on-rails": "^1.0.1",
+    "rescript-react-on-rails": "1.1.0",
     "resolve-url-loader": "^2.2.0",
     "sanitize-html": "^2.11.0",
     "sass": "^1.58.3",

yarn.lock

@@ -7268,10 +7268,10 @@ react-is@^18.0.0:
   resolved "https://registry.yarnpkg.com/react-is/-/react-is-18.2.0.tgz#199431eeaaa2e09f86427efbb4f1473edb47609b"
   integrity sha512-xWGDIW6x921xtzPkhiULtthJHoJvBbF3q26fzloPCK0hsvxtPVelvftw3zjbHWSkR2km9Z+4uxbDDK/6Zw9B8w==
 
-react-on-rails@14.2.1:
-  version "14.2.1"
-  resolved "https://registry.npmjs.org/react-on-rails/-/react-on-rails-14.2.1.tgz#e3072f21bb76a45de789fc78046d2bf0d9496878"
-  integrity sha512-1a7RCDzhM2/oAZChnJMcYDV023Gl6nwa5SAS+NW13jIpkigihiRw2ecYAFSjQq2BfCnASDw2z1ElmfTXhrYagw==
+react-on-rails@16.0.1-rc.2:
+  version "16.0.1-rc.2"
+  resolved "https://registry.npmjs.org/react-on-rails/-/react-on-rails-16.0.1-rc.2.tgz#efa95be66173f7653d954271005a38814cbb6065"
+  integrity sha512-A4aiSqoFpebpFlW5aFf0+vm+icFazO6PHmyvs9PdEfvgSwvFfakvYZ132hrNsZmHdHB+nl8C+xg0gFxG7lMmfA==
 
 react-proxy@^1.1.7:
   version "1.1.8"
@@ -7499,10 +7499,10 @@ requires-port@^1.0.0:
   resolved "https://registry.yarnpkg.com/requires-port/-/requires-port-1.0.0.tgz#925d2601d39ac485e091cf0da5c6e694dc3dcaff"
   integrity sha512-KigOCHcocU3XODJxsu8i/j8T9tzT4adHiecwORRQ0ZZFcp7ahwXuRU1m+yuO90C5ZUyGeGfocHDI14M3L3yDAQ==
 
-rescript-react-on-rails@^1.0.1:
-  version "1.0.1"
-  resolved "https://registry.yarnpkg.com/rescript-react-on-rails/-/rescript-react-on-rails-1.0.1.tgz#541dffdae64ec5053a50a3792b9db8783c959d1b"
-  integrity sha512-sbkDNCoiEWM9rqIiu+4joAj6W92yhM64KtLZQYfvYYm578jMcG02d98xpDeBT7MxZoPZZggFIed0m6Dj8bbDYA==
+rescript-react-on-rails@1.1.0:
+  version "1.1.0"
+  resolved "https://registry.npmjs.org/rescript-react-on-rails/-/rescript-react-on-rails-1.1.0.tgz#391eaaab3fa70cbee501a30e99dcb806ce5d16ed"
+  integrity sha512-ujYfNlf8nm2wivoFWXanuluLT3K22oCgmB6oAUHtCNZ0ObXutZBtSmptkrWpMkGQViZ9Y+VsLBcYkgdwFccXrg==
 
 rescript@^11.1.4:
   version "11.1.4"