add busboy tests

[KhafraDev]

No description provided.

[KhafraDev]

I removed all the tests that relied on busboy's limits, partial parsing, and some other things. Once I add info to the actual parsing we should be able to see what issues in the parsing there are (if any, I hope).

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 90.00000% with 2 lines in your changes are missing coverage. Please review.

Project coverage is 93.69%. Comparing base (03a2d43) to head (56c0080).
Report is 1 commits behind head on main.

Files	Patch %	Lines
lib/web/fetch/formdata-parser.js	90.00%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2924      +/-   ##
==========================================
+ Coverage   93.64%   93.69%   +0.05%     
==========================================
  Files          86       86              
  Lines       23862    23879      +17     
==========================================
+ Hits        22345    22374      +29     
+ Misses       1517     1505      -12     

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[KhafraDev]

Surprisingly not many issues left, seemingly only edge cases that the RFCs aren't too open about.

• does the value of "name" have to be surrounded in quotes?
• supporting filename* params (we don't have to, but we should)
• empty content-disposition header ("Each part MUST contain a Content-Disposition header field [RFC2183] where the disposition type is "form-data".")
• folded header value ("Header fields are lines beginning with a field name, followed by a colon (":"), followed by a field body, and terminated by CRLF.").
• no content-disposition (same reason as before)
• empty part (I think the only actual bug here, a form-data could start with \r\n)

@Uzlopak do you know why busboy/fastify's busboy supports some of these cases that go against the spec?

[Uzlopak]

We had cases where busboy would throw errors and crashing servers. I think you are referring to those cases, where we handled them gracefully to avoid server crashes.

Also we had issues like these fastify/busboy#71 where the implementation into busboy is not trivial.

[KhafraDev]

It's in busboy, not @fastify/busboy fwiw. I just thought the libraries were pretty similar.

[Uzlopak]

Cant we just take the cases and write a node:test based runner?

[KhafraDev]

yeah, I'm more interested in fixing the two valid cases first before doing so. I'm thinking that busboy is clearly wrong to handle the other cases so we shouldn't.

[KhafraDev]

@Uzlopak ptal

[mcollina]

lgtm