undici/lib/fetch/headers.js: Unexpected token (300:44)

[BRoy98]

Bug Description

Getting this error on serverless project.

Error: Parsing file .../test_server/node_modules/undici/lib/fetch/headers.js: Unexpected token (300:44)
      at Deps.parseDeps (.../test_server/node_modules/module-deps/index.js:519:15)
      at getDeps (.../test_server/node_modules/module-deps/index.js:447:44)
      at .../test_server/node_modules/module-deps/index.js:430:38
      at ConcatStream.<anonymous> (.../test_server/node_modules/concat-stream/index.js:37:43)
      at ConcatStream.emit (node:events:532:35)
      at ConcatStream.emit (node:domain:475:12)
      at finishMaybe (.../test_server/node_modules/readable-stream/lib/_stream_writable.js:630:14)
      at endWritable (.../test_server/node_modules/readable-stream/lib/_stream_writable.js:638:3)
      at ConcatStream.Writable.end (.../test_server/node_modules/readable-stream/lib/_stream_writable.js:594:41)
      at DuplexWrapper.onend (.../test_server/node_modules/readable-stream/lib/_stream_readable.js:577:10)
      at Object.onceWrapper (node:events:639:28)
      at DuplexWrapper.emit (node:events:532:35)
      at DuplexWrapper.emit (node:domain:475:12)
      at endReadableNT (.../test_server/node_modules/readable-stream/lib/_stream_readable.js:1010:12)
      at processTicksAndRejections (node:internal/process/task_queues:83:21)

Reproducible By

Here is an example repository for the issue: https://github.com/BRoy98/undici-serverless

Note: It happens only when serverless-plugin-optimize is being used to optimize the handlers.

Steps to reproduce:

• Clone the repository
• Install dependencies: yarn install
• Invoke the function: yarn invoke

To disable the optimize plugin, uncomment #L10 on serverless.yml: https://github.com/BRoy98/undici-serverless/blob/b15fb3ad50c1a2f81d1391636bc06a1794684622/serverless.yml#L10

Expected Behavior

Should run without error.

Environment

Tested on: MacOS monterey 12.4 (21F79) and Ubuntu Latest (github actions) Node v16.14.0 and Node v14.19.3

[mcollina]

Can you provide steps to reproduce? We often need a reproducible example, e.g. some code that allows someone else to recreate your problem by just copying and pasting it. If it involves more than a couple of different file, create a new repository on GitHub and add a link to that.

[KhafraDev]

I think this is another issue with using ??= again?

https://github.com/nodejs/undici/blob/966a54ff80993573d1baab5999ce258ccc0e7ec9/lib/fetch/headers.js#L300

[mcollina]

Can we add a test?

[targos]

Isn't that a problem with the module-deps module or one of its dependencies? It has to support this syntax.

[KhafraDev]

It's been a frequent problem when bundling undici on node 14 using webpack, etc.

See #1397 (actually this exact issue) and https://github.com/nodejs/undici/pull/1318

[BRoy98]

Can you provide steps to reproduce? We often need a reproducible example, e.g. some code that allows someone else to recreate your problem by just copying and pasting it. If it involves more than a couple of different file, create a new repository on GitHub and add a link to that.

Updated description with a reproducible example repository. Please check.

[avanelli]

Digging in a little bit, it is the parser https://github.com/acornjs/acorn that seems not to support Logical nullish assignment (??=)

I'm going to investigate a little more and eventually open an issue about this.

Error:
SyntaxError: Unexpected token (300:44)
    at _class.pp$4.raise (/workspace/undici-serverless/node_modules/acorn/dist/acorn.js:2931:15)
    at _class.pp.unexpected (/workspace/undici-serverless/node_modules/acorn/dist/acorn.js:700:10)
    at _class.pp$3.parseExprAtom (/workspace/undici-serverless/node_modules/acorn/dist/acorn.js:2328:12)
...
...
    at endReadableNT (/workspace/undici-serverless/node_modules/readable-stream/lib/_stream_readable.js:1010:12)
    at processTicksAndRejections (node:internal/process/task_queues:83:21)

[avanelli]

It seems we need to wait for these 2 issues to resolve #https://github.com/browserify/detective/issues/88 #https://github.com/browserify/acorn-node/issues/17

[ronag]

If you want you can open a PR to remove ?? in undici.

[jimmywarting]

think that acorn/detective should be updated to support ?? will help more ppl that use ?? elsewhere that don't just use undici

[avanelli]

??= assignment converted