Re: Bug Report: Multi-line trailers containing empty lines break parsing

From: Junio C Hamano <gitster@pobox.com>
Date: Feb 16, 2021, 02:29 UTC
Message-ID: <xmqqczx0sq1o.fsf@gitster.c.googlers.com>
In-Reply-To: <CALz+XyW+XU++58eEYm5=jxTckK-VuuPoA-ecj4QCZw1o44JFUQ@mail.gmail.com>

Matthias Buehlmann <Matthias.Buehlmann@mabulous.com> writes:

> Thank you for filling out a Git bug report!
> Please answer the following questions to help us understand your issue.

Thanks; let's ping our resident trailers expert ;-)

I somehow thought that a trailer is always a single-line thing, without funky line-folding that we have to deal with when we are dealing with e-mail headers.

Show 79 quoted lines

> What did you do before the bug happened? (Steps to reproduce your issue)
>
>     create a file containing multiline trailer:
>
>     $ echo "Test" > test.txt
>     $ git interpret-trailers --where end --if-exists addIfDifferent
> --trailer "SingleLineTrailer: This is a single line trailer"
> --in-place test.txt
>     $ git interpret-trailers --where end --if-exists addIfDifferent
> --trailer "MultiLineTrailer: This is"$'\n a folded multi-line\n
> trailer' --in-place test.txt
>
>     parse trailers:
>
>     $ git interpret-trailers --parse test.txt
>     SingleLineTrailer: This is a single line trailer
>     MultiLineTrailer: This is a folded multi-line trailer
>
>     (so far, all is as expected)
>
>     now, adding multiline trailer containing empty line:
>
>     $ git interpret-trailers --where end --if-exists addIfDifferent
> --trailer "MultiLineTrailer: This is"$'\n a folded multi-line\n
> trailer which\n \n contains an\n empty line' --in-place test.txt
>
>     parse trailers again:
>
>     $ git interpret-trailers --parse test.txt
>
> What did you expect to happen? (Expected behavior)
>
> I would expect the following output:
>
>     $ git interpret-trailers --parse test.txt
>     SingleLineTrailer: This is a single line trailer
>     MultiLineTrailer: This is a folded multi-line trailer
>     MultiLineTrailer: This is a folded multi-line trailer which
> contains an empty line
>
> What happened instead? (Actual behavior)
>
>     no output is generated, but exit code is nevertheless 0:
>
>     $ git interpret-trailers --parse test.txt
>     $ echo $?
>     0
>
> What's different between what you expected and what actually happened?
>
>     I would expect either to get an output or the call to exit non-zero
>
> Anything else you want to add:
>
>     According to my interpretation of the documentation of git
> intepret-trailers, empty lines should be supported if properly folded,
> in the same way as for example the PGP signature added to the commit
> header contains a (properly folded) empty line
>
> Please review the rest of the bug report below.
> You can delete any lines you don't wish to share.
>
>
> [System Info]
> git version:
> git version 2.30.0.windows.2
> cpu: x86_64
> built from commit: f8cbc844b81bf6b9e72178bbe891a86c8bf5e9e7
> sizeof-long: 4
> sizeof-size_t: 8
> shell-path: /bin/sh
> uname: Windows 10.0 18363
> compiler info: gnuc: 10.2
> libc info: no libc information available
> $SHELL (typically, interactive shell): C:\Program Files\Git\usr\bin\bash.exe
>
>
> [Enabled Hooks]
> post-commit