feat: disable colors if agent is detected

packages/vitest/src/node/cli/cac.ts

@@ -5,8 +5,9 @@ import type { CLIOption, CLIOptions as CLIOptionsConfig } from './cli-config'
 import { toArray } from '@vitest/utils/helpers'
 import cac from 'cac'
 import { normalize } from 'pathe'
-import c from 'tinyrainbow'
+import c, { disableDefaultColors } from 'tinyrainbow'
 import { version } from '../../../package.json' with { type: 'json' }
+import { isAgent } from '../../utils/env'
 import { benchCliOptionsConfig, cliOptionsConfig, collectCliOptionsConfig } from './cli-config'
 import { setupTabCompletions } from './completions'
 
@@ -74,6 +75,10 @@ function addCliOptions(cli: CAC | Command, options: CLIOptionsConfig<any>) {
 }
 
 export function createCLI(options: CliParseOptions = {}): CAC {
+  if (isAgent) {
+    disableDefaultColors()
+  }
+
   const cli = cac('vitest')
 
   cli.version(version)

packages/vitest/src/node/cli/cli-config.ts

@@ -1,7 +1,6 @@
 import type { ApiConfig } from '../types/config'
 import type { CliOptions } from './cli-api'
 import { defaultBrowserPort, defaultPort } from '../../constants'
-import { ReportersMap } from '../reporters'
 
 type NestedOption<T, V = Extract<T, Record<string, any>>> = V extends
   | never
@@ -141,7 +140,7 @@ export const cliOptionsConfig: VitestCLIOptions = {
   },
   reporters: {
     alias: 'reporter',
-    description: `Specify reporters (${Object.keys(ReportersMap).join(', ')})`,
+    description: `Specify reporters (default, agent, blob, verbose, dot, json, tap, tap-flat, junit, tree, hanging-process, github-actions)`,
     argument: '<name>',
     subcommands: null, // don't support custom objects
     array: true,

packages/vitest/src/node/config/serializeConfig.ts

@@ -1,6 +1,7 @@
 import type { TestProject } from '../project'
 import type { ApiConfig, SerializedConfig } from '../types/config'
 import { configDefaults } from '../../defaults'
+import { isAgent } from '../../utils/env'
 
 export function serializeConfig(project: TestProject): SerializedConfig {
   const { config, globalConfig } = project
@@ -146,5 +147,6 @@ export function serializeConfig(project: TestProject): SerializedConfig {
       config.slowTestThreshold
       ?? globalConfig.slowTestThreshold
       ?? configDefaults.slowTestThreshold,
+    isAgent,
   }
 }

packages/vitest/src/runtime/config.ts

@@ -146,6 +146,7 @@ export interface SerializedConfig {
   tagsFilter: string[] | undefined
   strictTags: boolean
   slowTestThreshold: number | undefined
+  isAgent: boolean
 }
 
 export interface SerializedCoverageConfig {

packages/vitest/src/runtime/workers/init.ts

@@ -3,6 +3,7 @@ import type { WorkerRequest, WorkerResponse } from '../../node/pools/types'
 import type { WorkerSetupContext } from '../../types/worker'
 import type { VitestWorker } from './types'
 import { serializeError } from '@vitest/utils/error'
+import { disableDefaultColors } from 'tinyrainbow'
 import { Traces } from '../../utils/traces'
 import * as listeners from '../listeners'
 import { createRuntimeRpc } from '../rpc'
@@ -49,6 +50,10 @@ export function init(worker: Options): void {
         process.env.VITEST_WORKER_ID = String(message.workerId)
         reportMemory = message.options.reportMemory
 
+        if (message.context.config.isAgent) {
+          disableDefaultColors()
+        }
+
         traces ??= await new Traces({
           enabled: message.traces.enabled,
           sdkPath: message.traces.sdkPath,

pnpm-workspace.yaml

@@ -81,7 +81,7 @@ catalog:
   tinyexec: ^1.0.2
   tinyglobby: ^0.2.15
   tinyhighlight: ^0.3.2
-  tinyrainbow: ^3.0.3
+  tinyrainbow: ^3.1.0
   tinyspy: ^4.0.4
   typescript: ^5.9.3
   unocss: ^66.6.6

test/config/test/console-color.test.ts

@@ -1,5 +1,5 @@
 import { expect, test } from 'vitest'
-import { runVitest } from '../../test-utils'
+import { runVitest, runVitestCli } from '../../test-utils'
 
 test('with color', async () => {
   const { stdout } = await runVitest({
@@ -30,6 +30,20 @@ test('without color', async () => {
   expect(stdout).not.toContain('\x1B[33mtrue\x1B[39m\n')
 })
 
+test('agent', async () => {
+  // Agent check is done on module import, so new process is needed
+  const { stdout } = await runVitestCli({
+    preserveAnsi: true,
+    nodeOptions: { env: { AI_AGENT: 'copilot' } },
+  }, '--root', 'fixtures/console-color', '--reporter', 'default')
+
+  expect.soft(stdout).toContain('true\n')
+  expect.soft(stdout).not.toContain('\x1B[33mtrue\x1B[39m\n')
+
+  expect.soft(stdout).toContain(' RUN')
+  expect.soft(stdout).not.toContain('\x1B[46m RUN')
+})
+
 test.skipIf(process.platform === 'win32')('without color, forks pool in non-TTY parent', async () => {
   const { stdout } = await runVitest({
     root: 'fixtures/console-color',