feat: show mode on server start and add env debugger

packages/vite/src/node/cli.ts

@@ -194,6 +194,10 @@ cli
 
       const info = server.config.logger.info
 
+      const modeString =
+        options.mode && options.mode !== 'development'
+          ? `  ${colors.bgGreen(` ${colors.bold(options.mode)} `)}`
+          : ''
       const viteStartTime = global.__vite_start_time ?? false
       const startupDurationString = viteStartTime
         ? colors.dim(
@@ -208,7 +212,7 @@ cli
       info(
         `\n  ${colors.green(
           `${colors.bold('VITE')} v${VERSION}`,
-        )}  ${startupDurationString}\n`,
+        )}${modeString}  ${startupDurationString}\n`,
         {
           clear: !hasExistingLogs,
         },

packages/vite/src/node/env.ts

@@ -2,9 +2,11 @@ import fs from 'node:fs'
 import path from 'node:path'
 import { parse } from 'dotenv'
 import { type DotenvPopulateInput, expand } from 'dotenv-expand'
-import { arraify, normalizePath, tryStatSync } from './utils'
+import { arraify, createDebugger, normalizePath, tryStatSync } from './utils'
 import type { UserConfig } from './config'
 
+const debug = createDebugger('vite:env')
+
 export function getEnvFilesForMode(mode: string, envDir: string): string[] {
   return [
     /** default file */ `.env`,
@@ -19,6 +21,9 @@ export function loadEnv(
   envDir: string,
   prefixes: string | string[] = 'VITE_',
 ): Record<string, string> {
+  const start = performance.now()
+  const getTime = () => `${(performance.now() - start).toFixed(2)}ms`
+
   if (mode === 'local') {
     throw new Error(
       `"local" cannot be used as a mode name because it conflicts with ` +
@@ -29,6 +34,8 @@ export function loadEnv(
   const env: Record<string, string> = {}
   const envFiles = getEnvFilesForMode(mode, envDir)
 
+  debug?.(`loading env files: %O`, envFiles)
+
   const parsed = Object.fromEntries(
     envFiles.flatMap((filePath) => {
       if (!tryStatSync(filePath)?.isFile()) return []
@@ -37,6 +44,8 @@ export function loadEnv(
     }),
   )
 
+  debug?.(`env files loaded in ${getTime()}`)
+
   // test NODE_ENV override before expand as otherwise process.env.NODE_ENV would override this
   if (parsed.NODE_ENV && process.env.VITE_USER_NODE_ENV === undefined) {
     process.env.VITE_USER_NODE_ENV = parsed.NODE_ENV
@@ -69,6 +78,8 @@ export function loadEnv(
     }
   }
 
+  debug?.(`using resolved env: %O`, env)
+
   return env
 }