methodOverride retains stale Content-Length after rewriting a form body #5520

import { Hono } from 'hono'
import { methodOverride } from 'hono/method-override'

const app = new Hono()
app.use('/posts', methodOverride({ app }))
app.delete('/posts', async (c) => {
  const body = await c.req.text()
  return c.json({
    body,
    actualBytes: new TextEncoder().encode(body).length,
    contentLength: c.req.header('content-length'),
  })
})

const response = await app.request('/posts', {
  method: 'POST',
  body: '_method=DELETE&message=Hello',
  headers: {
    'Content-Type': 'application/x-www-form-urlencoded',
    'Content-Length': '28',
  },
})
console.log(await response.json())
// { body: 'message=Hello', actualBytes: 13, contentLength: '28' }