Files
next.js/test/e2e/deprecation-warnings/deprecation-warnings.test.ts
Tim NeutkensGitHubVercel <vercel[bot]@users.noreply.github.com>
fd2bd2952e Move Ready in time before handler initialization (#88235)
## Move "Ready in X" log before config loading and eliminate duplicate
`loadConfig` calls

### What?

Reorder the dev server startup flow so the "Ready in X" log appears
before loading the user's `next.config.js`, and eliminate duplicate
`loadConfig` calls in both dev and build paths.

### Why?

Previously, the "Ready in X" time included the time spent loading and
evaluating the user's `next.config.js` file. This made the framework
appear slower than it actually is, especially for projects with complex
config files or slow config evaluation.

Additionally, config was being loaded twice:
- **Dev server**: Once in `getStartServerInfo()` just for logging, then
again in `getRequestHandlers()`
- **Build**: Once for the main build, then again in
`getStartServerInfo()` just for logging

### How?

**Before:**
```
1. getStartServerInfo() → loadConfig #1 (slow - blocks on next.config.js)
2. logStartInfo() → logs version, URLs, experimental features
3. "Ready in X" ← time includes config loading
4. getRequestHandlers() → loadConfig #2
```

**After:**
```
1. logStartInfo() → logs version, URLs, envInfo (no config needed)
2. "Ready in X" ← reflects actual framework startup time
3. getRequestHandlers() → loadConfig (once)
4. logExperimentalInfo() → logs experimental features
```

**Changes:**

- Split `logStartInfo` into two functions:
- `logStartInfo()` - basic info (version, URLs, env) - no config needed
  - `logExperimentalInfo()` - experimental features and cacheComponents
- Removed `getStartServerInfo()` which was loading config unnecessarily
- Added `experimentalFeatures` and `cacheComponents` to
`ServerInitResult` so they can be passed back after config loads
- In build, added `reportExperimentalFeatures` callback to the existing
`loadConfig` call instead of loading config twice

---------

Co-authored-by: Vercel <vercel[bot]@users.noreply.github.com>
2026-01-08 19:09:50 +01:00

60 lines
1.9 KiB
TypeScript

import { nextTestSetup } from 'e2e-utils'
import { retry } from 'next-test-utils'
import path from 'path'
describe('deprecation-warnings', () => {
describe('without next.config.js', () => {
const { next } = nextTestSetup({
files: path.join(__dirname, 'fixtures/no-config'),
skipStart: true,
})
it('should not emit any deprecation warnings when no config file exists', async () => {
await next.start()
const logs = next.cliOutput
expect(logs).not.toContain('deprecated')
expect(logs).not.toContain('has been renamed')
expect(logs).not.toContain('no longer needed')
})
})
describe('with deprecated config options', () => {
const { next } = nextTestSetup({
files: path.join(__dirname, 'fixtures/with-deprecated-config'),
skipStart: true,
})
it('should emit deprecation warnings for explicitly configured deprecated options', async () => {
await next.start()
await retry(async () => {
const logs = next.cliOutput
// Should warn about experimental.instrumentationHook
expect(logs).toContain('experimental.instrumentationHook')
expect(logs).toContain('no longer needed')
// Should warn about middleware config options
expect(logs).toContain('experimental.middlewarePrefetch')
expect(logs).toContain(
'Please use `experimental.proxyPrefetch` instead'
)
expect(logs).toContain('experimental.middlewareClientMaxBodySize')
expect(logs).toContain(
'Please use `experimental.proxyClientMaxBodySize` instead'
)
expect(logs).toContain('experimental.externalMiddlewareRewritesResolve')
expect(logs).toContain(
'Please use `experimental.externalProxyRewritesResolve` instead'
)
expect(logs).toContain('skipMiddlewareUrlNormalize')
expect(logs).toContain('Please use `skipProxyUrlNormalize` instead')
})
})
})
})