Re: [PATCH] sub-process: print the cmd when a capability is unsupported

[Lars Schneider <larsxschneider@gmail.com>]

> On 17 Aug 2017, at 23:01, Junio C Hamano <gitster@pobox.com> wrote:
> 
> Christian Couder <christian.couder@gmail.com> writes:
> 
>> ... but I think we should then emphasize more in our test
>> scripts (maybe by giving a good example) and perhaps also in the doc
>> that the filters/sub-processes should really pay attention and not
>> output any capability that are not supported by Git.
> 
> Oh, absolutely.  If you know there is such a breakage in our test
> script, please do fix it.
> 
> Thanks.

Junio's reasoning [1] is spot on from my point of view.

I intentionally did not add the negotiation to the test code to keep
the test as simple as possible. However, I wrote this in the
gitattributes docs [2]:

  After the version negotiation Git sends a list of all capabilities that
  it supports and a flush packet. Git expects to read a list of desired
  capabilities, which must be a subset of the supported capabilities list,
  and a flush packet as response:

Maybe we should revive "Documentation/technical/api-sub-process.txt" [3]
after all to explain these kind of things?

- Lars


[1] https://public-inbox.org/git/xmqq8tijpkrv.fsf@gitster.mtv.corp.google.com/
[2] https://github.com/git/git/blob/b3622a4ee94e4916cd05e6d96e41eeb36b941182/Documentation/gitattributes.txt#L408-L411
[3] https://public-inbox.org/git/20170807102136.30b23023@twelve2.svl.corp.google.com/