bug#54259: pypi importer prints backtrace when no source package exists

[Ludovic Courtès]

Hi,

Ricardo Wurmus <rekado@elephly.net> skribis:

> The only download for the kaleido package on Pypi is a binary.  There is
> no source code on Pypi.  The importer recognizes this but then prints a
> confusing backtrace when attempting to print a hint:
>
> ./pre-inst-env guix import pypi kaleido
> guix import: error: no source release for pypi package kaleido 0.2.1.post1
>
> hint: Backtrace:

[...]

> texinfo.scm:92:2: In procedure loop:
> Throw to key `parser-error' with args `(#f "@-command expected more 
> arguments:" () (url #:opt title replacement) (url #:opt title replacement))'.

Fixed in ebb03447f8cc93b9e070b3e7706d7a64d5d1772c.

The problem was with projects that lack a home page on PyPI.  For
others, the result looks like this:

--8<---------------cut here---------------start------------->8---
$ ./pre-inst-env guix import pypi torch
guix import: error: no source release for pypi package torch 1.10.2

hint: This indicates that the package is available on PyPI, but only as a 
"wheel" containing
binaries, not source.  To build it from source, refer to the upstream 
repository at
`https://pytorch.org/'.
--8<---------------cut here---------------end--------------->8---

Ludo’.