Subject: [bug#61910] [PATCH] git-download: Download a bare Git repository from SWH.

From: Simon Tournier <[email-masked]>
Date: Thu, 2 Mar 2023 14:50:56 +0100

Re,

On Thu, 2 Mar 2023 at 14:15, Ludovic Courtès <[email-masked]> wrote:

> Should we replace (find-files …) with (file-exists? ".gitattributes")?

Damned!  It was what I was looking for. :-)

> I wonder if we could achieve the same without creating a repo just to
> delete it afterwards, either by invoking a low-level ‘git’ command it if
> exists, or using Guile-Git, or doing it ourselves in Scheme.

Doing it ourselves in Scheme, I do not know.  I guess it would be
hard.  Basically, it is not clear for me what we would have to
implement.  For instance, we get the ("normalized") content fetched
from SWH , so we have:

--8<---------------cut here---------------start------------->8---
hidapi.swh/testgui/test.cpp:            C++ source, ASCII text
hidapi.swh/testgui/testgui.sln:         UTF-8 Unicode (with BOM) text
hidapi.swh/testgui/testgui.vcproj:      XML 1.0 document, ASCII text
--8<---------------cut here---------------end--------------->8---

and we need:

--8<---------------cut here---------------start------------->8---
hidapi.guix/testgui/test.cpp:            C++ source, ASCII text
hidapi.guix/testgui/testgui.sln:         UTF-8 Unicode (with BOM)
text, with CRLF line terminators
hidapi.guix/testgui/testgui.vcproj:      XML 1.0 document, ASCII text,
with CRLF line terminators
--8<---------------cut here---------------end--------------->8---

So the question is how to know which files require CRLF and which not?

>From my understanding, this information is provided by:

--8<---------------cut here---------------start------------->8---
$ cat hidapi.guix/.gitattributes
* text=auto

*.sln text eol=crlf
*.vcproj text eol=crlf

bootstrap text eol=lf
configure.ac text eol=lf
--8<---------------cut here---------------end--------------->8---

As zack pointed yesterday, well that what I understood or
misunderstood, it is related to "smudge" filters [1].

1: <https://git-scm.com/book/en/v2/Customizing-Git-Git-Attributes>

About Guile-Git, probably the same as you answered me earlier today. ;-)

        <civodul> it's just that it was easier to implement and yeah,
shallow clones
                  are nice
        <civodul> we don't need tight integration in this context, so less of an
                  incentive to use Guile-Git
        <civodul> (it's very different from the channel code from that
perspective)

Kidding aside, I agree that relying on Guile-Git would mean being less
"fragile".  Hum, somehow this asks about the size of the binary seed
for bootstrapping.

About low-level 'git' command, maybe the same could be achieved
without "git init" + "git add" + "git commit".  Well, my gitology is
not enough skilled. :-)

Cheers,
simon