fix(cli): keep logs off stdout (#5207)

puneetdixit200 · Deepak kudi · web-flow · commit 548e1c82b3c2 · 2026-05-22T01:58:47.000Z
Co-authored-by: Deepak kudi &lt;deepakkudi23@adsl-172-10-9-116.dsl.sndg02.sbcglobal.net&gt;
diff --git a/packages-engine/cli/src/index.ts b/packages-engine/cli/src/index.ts
@@ -17,6 +17,12 @@ import { debugDetailsTable } from './debug'
 import { handleError, PrettyError } from './errors'
 import { getWatcher } from './watcher'
 
+function createCliLogger(options: Pick<CliOptions, 'stdout'>) {
+  return options.stdout
+    ? consola.create({ stdout: process.stderr })
+    : consola
+}
+
 async function resolveOptions(options: CliOptions, userConfig: ResolvedConfig): Promise<ResolvedCliOptions> {
   const resolvedOptions = {
     ...options,
@@ -48,7 +54,9 @@ async function resolveOptions(options: CliOptions, userConfig: ResolvedConfig):
   }
 
   if (resolvedOptions.writeTransformed) {
-    consola.warn(`--write-transformed is deprecated, please use ${yellow('--rewrite')} instead.`)
+    createCliLogger(options).warn(
+      `--write-transformed is deprecated, please use ${yellow('--rewrite')} instead.`,
+    )
   }
 
   return resolvedOptions
@@ -138,24 +146,25 @@ export async function build(_options: CliOptions) {
   const fileCache = new Map<string, FileEntryItem[]>()
   const configResult = await initializeConfig(_options)
   const options = await resolveOptions(_options, configResult.config)
+  const logger = createCliLogger(options)
   options.ctx = configResult.ctx
 
   if (options.stdout && options.outFile) {
-    consola.fatal(`Cannot use --stdout and --out-file at the same time`)
+    logger.fatal(`Cannot use --stdout and --out-file at the same time`)
     return
   }
 
-  consola.log(green(`UnoCSS v${version}`))
+  logger.log(green(`UnoCSS v${version}`))
 
   if (options.watch)
-    consola.start(`UnoCSS in watch mode...`)
+    logger.start(`UnoCSS in watch mode...`)
   else
-    consola.start(`UnoCSS for production...`)
+    logger.start(`UnoCSS for production...`)
 
   await parseEntries(options, fileCache)
 
   if (fileCache.size === 0) {
-    consola.warn('No files matched the provided patterns.')
+    logger.warn('No files matched the provided patterns.')
     return
   }
 
@@ -207,8 +216,8 @@ export async function build(_options: CliOptions) {
           watcher.add(configSources)
 
         if (type === 'change')
-          consola.info(`${cyan(basename(file))} changed, setting new config`)
-        consola.info(
+          logger.info(`${cyan(basename(file))} changed, setting new config`)
+        logger.info(
           `Watching for changes in ${
             [
               ...options.entries.flatMap(i => i.patterns),
@@ -220,7 +229,7 @@ export async function build(_options: CliOptions) {
       }
       else {
         if (type === 'change') {
-          consola.log(`${green(type)} ${dim(file)}`)
+          logger.log(`${green(type)} ${dim(file)}`)
           const content = await fs.readFile(absolutePath, 'utf8')
           const matchedEntry = fileCache.keys().find(outfile => outfile === absolutePath)
           if (matchedEntry)
@@ -234,7 +243,7 @@ export async function build(_options: CliOptions) {
           }
         }
         else if (type === 'unlink') {
-          consola.log(`${green(type)} ${dim(file)}`)
+          logger.log(`${green(type)} ${dim(file)}`)
           for (const [, files] of fileCache.entries()) {
             const index = files.findIndex(f => f.id === absolutePath)
             if (index !== -1) {
@@ -243,7 +252,7 @@ export async function build(_options: CliOptions) {
           }
         }
         else if (type === 'add') {
-          consola.log(`${green(type)} ${dim(file)}`)
+          logger.log(`${green(type)} ${dim(file)}`)
           await parseEntries(options, fileCache)
         }
       }
diff --git a/packages-engine/cli/test/cli.test.ts b/packages-engine/cli/test/cli.test.ts
@@ -1,8 +1,9 @@
+import { execa } from 'execa'
 import fs from 'fs-extra'
 import { resolve } from 'pathe'
 import { afterAll, beforeAll, describe, expect, it } from 'vitest'
 import { getWatcher } from '../src/watcher'
-import { getTestDir, readFile, runAsyncChildProcess, runCli, sleep, tempDir } from './utils'
+import { cli, getTestDir, readFile, runAsyncChildProcess, runCli, sleep, tempDir } from './utils'
 
 beforeAll(async () => {
   await fs.remove(tempDir)
@@ -185,6 +186,39 @@ describe('cli', () => {
     expect(output).not.toContain('.bg-red')
     expect(output).not.toContain('.text-white')
   })
+
+  it('keeps cli logs off stdout when writing generated css to stdout', async () => {
+    const testDir = getTestDir()
+    await fs.outputFile(resolve(testDir, 'views/index.html'), '<div class="bg-black"></div>', 'utf8')
+
+    const { stdout, stderr } = await execa(
+      'pnpm',
+      [
+        'exec',
+        'tsx',
+        cli,
+        resolve(testDir, 'views/index.html'),
+        '--stdout',
+        '--preset',
+        'wind4',
+        '--preflights',
+        'false',
+      ],
+      {
+        env: {
+          NODE_ENV: 'development',
+          TEST: 'false',
+          VITEST: 'false',
+        },
+      },
+    )
+
+    expect(stdout).toContain('.bg-black')
+    expect(stdout).not.toContain('UnoCSS v')
+    expect(stdout).not.toContain('UnoCSS for production')
+    expect(stderr).toContain('UnoCSS v')
+    expect(stderr).toContain('UnoCSS for production')
+  })
 })
 
 describe.skipIf(process.version.startsWith('v20'))('cli watch mode', () => {
