fix(vite): drop Vite's notes that say nothing about the app

src/utils/vite.test.ts

@@ -1,6 +1,6 @@
 import { afterEach, describe, expect, it, vi } from 'vitest'
 import { join } from 'node:path'
-import { isVoidProject, loadVoidApp, startVite } from './vite'
+import { isViteNoise, isVoidProject, loadVoidApp, startVite } from './vite'
 
 const FIXTURE = join(import.meta.dirname, 'fixtures/vite')
 const VOID_FIXTURE = join(import.meta.dirname, 'fixtures/void')
@@ -62,3 +62,17 @@ describe('startVite', () => {
     expect(isVoidProject()).toBe(false)
   })
 })
+
+describe('isViteNoise', () => {
+  it("drops Vite's own notes and keeps the app logs", () => {
+    expect(isViteNoise('Re-optimizing dependencies because vite config has changed')).toBe(true)
+    expect(isViteNoise('Default inspector port 9229 not available, using 9232 instead')).toBe(true)
+    expect(
+      isViteNoise(
+        'Sourcemap for "/a/node_modules/x/index.mjs" points to a source file outside its package: "/a/src/x.ts"'
+      )
+    ).toBe(true)
+    expect(isViteNoise('GET /users 200')).toBe(false)
+    expect(isViteNoise('Error: something broke')).toBe(false)
+  })
+})

src/utils/vite.ts

@@ -95,12 +95,25 @@ const loadVite = async (): Promise<ViteModule> => {
  * that a Vite plugin builds (with virtual modules) can take requests.
  * The server listens on a random port on 127.0.0.1 only.
  */
+const VITE_NOISE = [
+  /^Sourcemap for .* points to (a source file outside its package|missing source files)/,
+  /^Re-optimizing dependencies because/,
+  /^Default inspector port \d+ not available/,
+]
+
+/** Vite's own notes that say nothing about the app */
+export const isViteNoise = (msg: string): boolean => VITE_NOISE.some((noise) => noise.test(msg))
+
 export const startVite = async (): Promise<ViteTarget> => {
   const { createLogger, createServer: createViteServer } = await loadVite()
   // Keep the app logs off stdout, which is for the JSON output. An app
   // in workerd logs through this logger; an app in this process (e.g.
   // @hono/vite-dev-server) calls console.log, so `request` wraps it.
-  const toStderr = (msg: string) => console.error(msg)
+  const toStderr = (msg: string) => {
+    if (!isViteNoise(msg)) {
+      console.error(msg)
+    }
+  }
   // Plugins may log with console.log while the server starts (Void does)
   const vite = await logsToStderr(() =>
     createViteServer({