bug#71113: git-fetch throws an error: gnutls_handshake() failed: An unexpected TLS packet was received.

[nigko]

Hello Guix!

When I try to download source code of any package that use
git-fetch download method I get an error if I am behind https proxy
server. For example,

$ guix build --no-substitutes -S eigen
The following derivations will be built:
/gnu/store/rsk8d4py0c5qgp7q4xzd9ci3w4l5wki5-eigen-3.4.0-checkout.drv
/gnu/store/ac69jx4b08rqd07v5m5ayd5dgh3b9798-eigen-3.4.0-checkout.drv
building /gnu/store/ac69jx4b08rqd07v5m5ayd5dgh3b9798-eigen-3.4.0-checkout.drv...
hint: Consider installing the `glibc-locales' package and defining
`GUIX_LOCPATH', along these lines:

guix install glibc-locales
export GUIX_LOCPATH="$HOME/.guix-profile/lib/locale"

See the "Application Setup" section in the manual, for more info.

Initialized empty Git repository in
/gnu/store/1syd2rljr26hx9y45645lxwfh1wsya50-eigen-3.4.0-checkout/.git/
fatal: unable to access 'https://gitlab.com/libeigen/eigen.git/':
gnutls_handshake() failed: An unexpected TLS packet was received.
Failed to do a shallow fetch; retrying a full fetch...
fatal: unable to access 'https://gitlab.com/libeigen/eigen.git/':
gnutls_handshake() failed: An unexpected TLS packet was received.
git-fetch:
'/gnu/store/lcygm0p2d59acvwi12lwldg5c0d4czpr-git-minimal-2.41.0/bin/git
fetch origin'
failed with exit code 128
Trying content-addressed mirror at bordeaux.guix.gnu.org...
...

But when I use 'git clone' like this:

$ guix shell --preserve=https_proxy -CN git nss-certs -- \
git clone https://gitlab.com/libeigen/eigen.git/

it works.

I looked into definitions of 'git' and 'git-minimal' packages.
They both do not depend on 'gnutls' package (at least directly),
but instead on 'openssl'. Then why is git-fetch method apparently
using 'gnutls' and not 'openssl'? Is there any workaround for
git-fetch (similar to package transformations) that allow to
replace 'gnutls' by 'openssl' in its dependency graph?

Regards,
Nigko