fix parsing when receiving empty body websocket (#3205)

lib/web/websocket/receiver.js

@@ -239,7 +239,7 @@ class ByteParser extends Writable {
         }
       }
 
-      if (this.#byteOffset === 0) {
+      if (this.#byteOffset === 0 && this.#info.payloadLength !== 0) {
         callback()
         break
       }

test/websocket/issue-3202.js

@@ -0,0 +1,35 @@
+'use strict'
+
+const { test } = require('node:test')
+const { WebSocketServer } = require('ws')
+const { WebSocket } = require('../..')
+const { tspl } = require('@matteo.collina/tspl')
+
+test('Receiving frame with payload length 0 works', async (t) => {
+  const { ok, completed } = tspl(t, { plan: 1 })
+
+  const server = new WebSocketServer({ port: 0 })
+
+  server.on('connection', (socket) => {
+    socket.on('message', () => {
+      socket.send('')
+    })
+  })
+
+  t.after(() => {
+    server.close()
+    ws.close()
+  })
+
+  const ws = new WebSocket(`ws://127.0.0.1:${server.address().port}`)
+
+  ws.addEventListener('open', () => {
+    ws.send('Hi')
+  })
+
+  ws.addEventListener('message', () => {
+    ok(true)
+  })
+
+  await completed
+})