`body-parser` errors out when Content-Type is present in express.js

[noway]

trafficstars

What version of Bun is running?

0.3.0

What platform is your computer?

Darwin 22.1.0 arm64 arm

What steps can reproduce the bug?

Repro script:

curl https://gist.githubusercontent.com/noway/87e2fba1fc4dd3d026a482126f770d92/raw/ade797bef21e81e7a94796a21dd23e9bc506734a/bun-express-body-parser-bug.sh | bash

Alternatively, go to https://gist.github.com/noway/87e2fba1fc4dd3d026a482126f770d92 and copy-paste the script into Terminal.

What is the expected behavior?

No errors, "ok" printed to console.

What do you see instead?

Two errors:

TypeError: Can only call StringDecoder.write on instances of StringDecoder
      at /Users/ilia/compiling/bun-express-body-parser-bug/node_modules/iconv-lite/lib/bom-handling.js:35:14
      at onData (/Users/ilia/compiling/bun-express-body-parser-bug/node_modules/raw-body/index.js:259:16)
      at addChunk (node:stream:3015:8)
      at readableAddChunk (node:stream:2988:12)
      at node:http:191:8
      at node:stream:3234:8
273 |         received: received,
274 |         type: 'request.size.invalid'
275 |       }))
276 |     } else {
277 |       var string = decoder
278 |         ? buffer + (decoder.end() || '')
                       ^
TypeError: Can only call StringDecoder.end on instances of StringDecoder
      at onEnd (/Users/ilia/compiling/bun-express-body-parser-bug/node_modules/raw-body/index.js:278:20)
      at endReadableNT (node:stream:3706:8)

Additional information

Seems to be only happening when Content-Type header is supplied. When I try removing Content-Type header on line index.ts:16, the bug goes away, but I can't do that for my use case since I am actually trying to send a request from a browser which sends it regardless.

[Jarred-Sumner]

Thank you for the report & repro

[noway]

Just tested the repro script on bun v0.4.0:

TypeError: undefined is not an object (evaluating 'this.#bodyStream.on')
      at node:http:198:23
POST - http://localhost:3000/ failed
Error: undefined is not an object (evaluating 'this.#bodyStream.on')
    at errorOrDestroy (native)
    at <anonymous> (node:stream:3194:11)

Looks like the error changed (progress yay) but the use case of using body-parser still doesn't work.