Inconsistencies between dev and build for this context

[gecugamo]

Describe the bug

I am using a package called rails-ujs.

What I expect is consistent behavior between dev and build. Currently, I have to add a runtime check to account for the differences between dev and build environments:

import Rails from 'rails-ujs';

if (!window._rails_loaded) {
  Rails.start();
}

What appears to be happening is during dev this is set to {} - during build this is set to window. This causes an if statement to become true in one environment but not the other, which needs to be corrected with a runtime check, else an error will occur.

Reproduction

https://github.com/gecugamo/vite-debugging/tree/main

Steps to reproduce

Compare app functionality during dev mode and build mode.

Setup

Run npm i

Dev

1. Run npm run dev
2. Visit http://localhost:5173
3. Check console
4. Observe no errors

Build

1. Run npm run build && npm run preview
2. Visit http://localhost:4173
3. Check console
4. Observe error "Uncaught Error: rails-ujs has already been loaded!"

System Info

npx envinfo --system --npmPackages '{vite,@vitejs/*,rollup}' --binaries --browsers

  System:
    OS: macOS 13.6
    CPU: (12) arm64 Apple M2 Max
    Memory: 4.48 GB / 32.00 GB
    Shell: 3.2.57 - /bin/bash
  Binaries:
    Node: 18.16.0 - ~/.nvm/versions/node/v18.16.0/bin/node
    Yarn: 1.22.19 - ~/.nvm/versions/node/v18.16.0/bin/yarn
    npm: 9.5.1 - ~/.nvm/versions/node/v18.16.0/bin/npm
  Browsers:
    Chrome: 117.0.5938.92
    Safari: 16.6
  npmPackages:
    vite: ^4.4.5 => 4.4.9

Used Package Manager

npm

Logs

Click to expand!

npm run build -- --debug

> [email protected] build
> tsc && vite build --debug

  vite:config no config file found. +0ms
  vite:config using resolved config: {
  vite:config   root: '/Users/gary.cugamoylan/Projects/vite-debugging',
  vite:config   base: '/',
  vite:config   mode: 'production',
  vite:config   configFile: undefined,
  vite:config   logLevel: undefined,
  vite:config   clearScreen: undefined,
  vite:config   optimizeDeps: {
  vite:config     disabled: 'build',
  vite:config     force: undefined,
  vite:config     esbuildOptions: { preserveSymlinks: false }
  vite:config   },
  vite:config   build: {
  vite:config     target: [ 'es2020', 'edge88', 'firefox78', 'chrome87', 'safari14' ],
  vite:config     cssTarget: [ 'es2020', 'edge88', 'firefox78', 'chrome87', 'safari14' ],
  vite:config     outDir: 'dist',
  vite:config     assetsDir: 'assets',
  vite:config     assetsInlineLimit: 4096,
  vite:config     cssCodeSplit: true,
  vite:config     sourcemap: false,
  vite:config     rollupOptions: {},
  vite:config     minify: 'esbuild',
  vite:config     terserOptions: {},
  vite:config     write: true,
  vite:config     emptyOutDir: null,
  vite:config     copyPublicDir: true,
  vite:config     manifest: false,
  vite:config     lib: false,
  vite:config     ssr: false,
  vite:config     ssrManifest: false,
  vite:config     ssrEmitAssets: false,
  vite:config     reportCompressedSize: true,
  vite:config     chunkSizeWarningLimit: 500,
  vite:config     watch: null,
  vite:config     commonjsOptions: { include: [Array], extensions: [Array] },
  vite:config     dynamicImportVarsOptions: { warnOnError: true, exclude: [Array] },
  vite:config     modulePreload: { polyfill: true },
  vite:config     cssMinify: true
  vite:config   },
  vite:config   configFileDependencies: [],
  vite:config   inlineConfig: {
  vite:config     root: undefined,
  vite:config     base: undefined,
  vite:config     mode: undefined,
  vite:config     configFile: undefined,
  vite:config     logLevel: undefined,
  vite:config     clearScreen: undefined,
  vite:config     optimizeDeps: { force: undefined },
  vite:config     build: {}
  vite:config   },
  vite:config   rawBase: '/',
  vite:config   resolve: {
  vite:config     mainFields: [ 'module', 'jsnext:main', 'jsnext' ],
  vite:config     browserField: true,
  vite:config     conditions: [],
  vite:config     extensions: [
  vite:config       '.mjs',  '.js',
  vite:config       '.mts',  '.ts',
  vite:config       '.jsx',  '.tsx',
  vite:config       '.json'
  vite:config     ],
  vite:config     dedupe: [],
  vite:config     preserveSymlinks: false,
  vite:config     alias: [ [Object], [Object] ]
  vite:config   },
  vite:config   publicDir: '/Users/gary.cugamoylan/Projects/vite-debugging/public',
  vite:config   cacheDir: '/Users/gary.cugamoylan/Projects/vite-debugging/node_modules/.vite',
  vite:config   command: 'build',
  vite:config   ssr: {
  vite:config     format: 'esm',
  vite:config     target: 'node',
  vite:config     optimizeDeps: { disabled: true, esbuildOptions: [Object] }
  vite:config   },
  vite:config   isWorker: false,
  vite:config   mainConfig: null,
  vite:config   isProduction: true,
  vite:config   plugins: [
  vite:config     'vite:build-metadata',
  vite:config     'vite:watch-package-data',
  vite:config     'vite:pre-alias',
  vite:config     'alias',
  vite:config     'vite:modulepreload-polyfill',
  vite:config     'vite:resolve',
  vite:config     'vite:html-inline-proxy',
  vite:config     'vite:css',
  vite:config     'vite:esbuild',
  vite:config     'vite:json',
  vite:config     'vite:wasm-helper',
  vite:config     'vite:worker',
  vite:config     'vite:asset',
  vite:config     'vite:wasm-fallback',
  vite:config     'vite:define',
  vite:config     'vite:css-post',
  vite:config     'vite:build-html',
  vite:config     'vite:worker-import-meta-url',
  vite:config     'vite:asset-import-meta-url',
  vite:config     'vite:force-systemjs-wrap-complete',
  vite:config     'commonjs',
  vite:config     'vite:data-uri',
  vite:config     'vite:dynamic-import-vars',
  vite:config     'vite:import-glob',
  vite:config     'vite:build-import-analysis',
  vite:config     'vite:esbuild-transpile',
  vite:config     'vite:terser',
  vite:config     'vite:reporter',
  vite:config     'vite:load-fallback'
  vite:config   ],
  vite:config   css: undefined,
  vite:config   esbuild: { jsxDev: false },
  vite:config   server: {
  vite:config     preTransformRequests: true,
  vite:config     sourcemapIgnoreList: [Function: isInNodeModules],
  vite:config     middlewareMode: false,
  vite:config     fs: { strict: true, allow: [Array], deny: [Array] }
  vite:config   },
  vite:config   preview: {
  vite:config     port: undefined,
  vite:config     strictPort: undefined,
  vite:config     host: undefined,
  vite:config     https: undefined,
  vite:config     open: undefined,
  vite:config     proxy: undefined,
  vite:config     cors: undefined,
  vite:config     headers: undefined
  vite:config   },
  vite:config   envDir: '/Users/gary.cugamoylan/Projects/vite-debugging',
  vite:config   env: { BASE_URL: '/', MODE: 'production', DEV: false, PROD: true },
  vite:config   assetsInclude: [Function: assetsInclude],
  vite:config   logger: {
  vite:config     hasWarned: false,
  vite:config     info: [Function: info],
  vite:config     warn: [Function: warn],
  vite:config     warnOnce: [Function: warnOnce],
  vite:config     error: [Function: error],
  vite:config     clearScreen: [Function: clearScreen],
  vite:config     hasErrorLogged: [Function: hasErrorLogged]
  vite:config   },
  vite:config   packageCache: Map(1) {
  vite:config     'fnpd_/Users/gary.cugamoylan/Projects/vite-debugging' => {
  vite:config       dir: '/Users/gary.cugamoylan/Projects/vite-debugging',
  vite:config       data: [Object],
  vite:config       hasSideEffects: [Function: hasSideEffects],
  vite:config       webResolvedImports: {},
  vite:config       nodeResolvedImports: {},
  vite:config       setResolvedCache: [Function: setResolvedCache],
  vite:config       getResolvedCache: [Function: getResolvedCache]
  vite:config     },
  vite:config     set: [Function (anonymous)]
  vite:config   },
  vite:config   createResolver: [Function: createResolver],
  vite:config   worker: {
  vite:config     format: 'iife',
  vite:config     plugins: [
  vite:config       'vite:build-metadata',
  vite:config       'vite:watch-package-data',
  vite:config       'vite:pre-alias',
  vite:config       'alias',
  vite:config       'vite:modulepreload-polyfill',
  vite:config       'vite:resolve',
  vite:config       'vite:html-inline-proxy',
  vite:config       'vite:css',
  vite:config       'vite:esbuild',
  vite:config       'vite:json',
  vite:config       'vite:wasm-helper',
  vite:config       'vite:worker',
  vite:config       'vite:asset',
  vite:config       'vite:wasm-fallback',
  vite:config       'vite:define',
  vite:config       'vite:css-post',
  vite:config       'vite:build-html',
  vite:config       'vite:worker-import-meta-url',
  vite:config       'vite:asset-import-meta-url',
  vite:config       'vite:force-systemjs-wrap-complete',
  vite:config       'commonjs',
  vite:config       'vite:data-uri',
  vite:config       'vite:worker-post',
  vite:config       'vite:dynamic-import-vars',
  vite:config       'vite:import-glob',
  vite:config       'vite:build-import-analysis',
  vite:config       'vite:esbuild-transpile',
  vite:config       'vite:terser',
  vite:config       'vite:load-fallback'
  vite:config     ],
  vite:config     rollupOptions: {},
  vite:config     getSortedPlugins: [Function: getSortedPlugins],
  vite:config     getSortedPluginHooks: [Function: getSortedPluginHooks]
  vite:config   },
  vite:config   appType: 'spa',
  vite:config   experimental: { importGlobRestoreExtension: false, hmrPartialAccept: false },
  vite:config   getSortedPlugins: [Function: getSortedPlugins],
  vite:config   getSortedPluginHooks: [Function: getSortedPluginHooks]
  vite:config } +14ms
vite v4.4.9 building for production...
  vite:esbuild 10.82ms tsconfck init /Users/gary.cugamoylan/Projects/vite-debugging +0ms
✓ 6 modules transformed.
dist/index.html                 0.39 kB │ gzip: 0.27 kB
dist/assets/index-b1745663.js  14.46 kB │ gzip: 4.47 kB
✓ built in 113ms

Validations

• Follow our Code of Conduct
• Read the Contributing Guidelines.
• Read the docs.
• Check that there isn't already an issue that reports the same bug to avoid creating a duplicate.
• Make sure this is a Vite issue and not a framework-specific issue. For example, if it's a Vue SFC related bug, it should likely be reported to vuejs/core instead.
• Check that this is a concrete bug. For Q&A open a GitHub Discussion or join our Discord Chat Server.
• The provided reproduction is a minimal reproducible example of the bug.

[sapphi-red]

Duplicate of #13537

[gecugamo]

I would argue that this is a vite issue, and not an upstream issue, as vite is the thing bringing esbuild and rollup together. As it stands, one is not able to be sure what they are seeing during dev will be reflected once they build.

I think that's the big issue for me - if it broke in the same way during both dev and build it'd be easier to account for.