Re: [PATCH] gnu: Make "guix-devel" a public variable in package-management.scm

[Ludovic Courtès]

Hi,

Chris Marusich <address@hidden> skribis:

> Here's a patch to address the following issue ('guix environment guix
> doesn't provide guix dependencies'):
>
> https://lists.gnu.org/archive/html/guix-devel/2016-09/msg02118.html

Thanks for looking into it!

> I signed the commit with my GPG key, but it seems that 'git
> format-patch' doesn't include the signature.  If you know how to make it
> include the signature, please let me know!

I think it can’t do that.  So in practice whoever pushes signs on your
behalf.

> From 3fa2bc4f0d11fc695bfab9b85981228c1a88e007 Mon Sep 17 00:00:00 2001
> From: Chris Marusich <address@hidden>
> Date: Sun, 2 Oct 2016 13:00:34 -0700
> Subject: [PATCH] gnu: Make "guix-devel" a public variable in
>  package-management.scm
>
> This provides an obvious and easy way to use Guix to set up an environment for
> building Guix from a Git checkout.
>
> * gnu/packages/package-management.scm (guix-devel): Make it public and give it
>   an appropriate name, synopsis, and description.  Change the generated
>   version string to be even shorter so that the tests can actually run.
>   Update all documentation to refer to "guix" when talking about the release
>   version, and "guix-devel" when talking about the development version.

[...]

> -(define guix-devel
> +(define-public guix-devel
>    ;; Development version of Guix.
>    ;;
>    ;; Note: use a very short commit id; with a longer one, the limit on
>    ;; hash-bang lines would be exceeded while running the tests.
>    (let ((commit "4420940f20a2f36f29519f686bca7b85be6be5c9"))
>      (package (inherit guix-0.11.0)
> -      (version (string-append "0.11.0-1." (string-take commit 4)))
> +      (name "guix-devel")
> +      (version (string-take commit 8))
>        (source (origin
>                  (method git-fetch)
>                  (uri (git-reference
> @@ -251,7 +252,16 @@ the Nix package manager.")
>           ("texinfo" ,texinfo)
>           ("graphviz" ,graphviz)
>           ("help2man" ,help2man)
> -         ,@(package-native-inputs guix-0.11.0))))))
> +         ,@(package-native-inputs guix-0.11.0)))
> +      (synopsis "Development version of GNU Guix")
> +      (description "GNU Guix is a functional package manager for the GNU
> +system, and is also a distribution thereof.  It includes a virtual machine
> +image.  Besides the usual package management features, it also supports
> +transactional upgrades and roll-backs, per-user profiles, and much more.  It
> +is based on the Nix package manager.  This is a development version which is
> +built from a recent commit in the project's Git repository.  It provides
> +additional dependencies that are not normally required for building the
> +release version, such as GNU Autoconf."))))
>  
>  (define-public guix guix-devel)

There’s the problem that the ‘guix-devel’ variable above is also the
Guix package that we currently use, and thus it should be called “guix”,
not “guix-devel”.

So what about something along these lines:

diff --git a/gnu/packages/package-management.scm 
b/gnu/packages/package-management.scm
index 70a6a49..8a77c40 100644
--- a/gnu/packages/package-management.scm
+++ b/gnu/packages/package-management.scm
@@ -255,6 +255,18 @@ the Nix package manager.")
 
 (define-public guix guix-devel)
 
+(define-public guix-for-environment
+  ;; We provide this pseudo-package just to allow people to run:
+  ;;   guix environment guix-devel
+  ;; to reliably get the development environment for Guix (using 'guix' for
+  ;; this purpose does not work when 'guix' points to the built-from-tarball
+  ;; package rather than to the built-from-checkout package.)
+  (package
+    (inherit guix-devel)
+    (name "guix-devel")
+    (source #f)                                   ;not meant to be built
+    (supported-systems '())))
+
 (define (source-file? file stat)
   "Return true if FILE is likely a source file, false if it is a typical
 generated file."

?

If that’s fine with you, could you incorporate it in your patch?

Minor comment: it’s useful to provide a specialized synopsis like you
did, but I think it’s better to leave the description unchanged rather
than duplicate it almost identical.

Thanks!

Ludo’.