bug#40891: import crate: Traceback when package not found

[Hartmut Goebel]

If "import crate" does not find the package, a traceback is shown (see
below)

I would expect an error message stating that the package was nor found
(or whatever crates.io error message is)

$ guix import crate non-exeisti[hartmut@lenashee [1] guix
(HG-sequoia-as-rust-pkgs)]$ guix import crate non-exeisting-package
Backtrace:
           4 (primitive-load "/usr/local/bin/guix")
In guix/ui.scm:
  1936:12  3 (run-guix-command _ . _)
In guix/scripts/import.scm:
   116:11  2 (guix-import . _)
In guix/scripts/import/crate.scm:
   104:23  1 (guix-import-crate . _)
In guix/import/crate.scm:
    205:8  0 (crate->guix-package "non-exeisting-package" _)

guix/import/crate.scm:205:8: In procedure crate->guix-package:
In procedure struct-vtable: Wrong type argument in position 1 (expecting
struct): #f

-- 
Regards
Hartmut Goebel

| Hartmut Goebel          | address@hidden               |
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