Subject: bug#21399: Emacs: Guix Package Info omits some inputs

From: Alex Kost <[email-masked]>
Date: Wed, 02 Sep 2015 18:20:25 +0300

Ludovic Courtès (2015-09-02 16:06 +0300) wrote:

> Hello,
>
> For ‘r’, the *Guix Package Info* buffer omits IcedTea from the set of
> inputs.  It shows this:
>
>
> Inputs            : openblas-0.2.14, cairo-1.14.2, gfortran-4.9.3, icu4c-55.1,
>                     lapack-3.5.0, libjpeg-9a, libpng-1.5.21, libtiff-4.0.3,
>                     libxt-1.1.4, pcre-8.37, readline-6.3, zlib-1.2.7
>
> whereas the recipe has this:
>
>
>     (inputs
>      `(("openblas" ,openblas)
>        ("cairo" ,cairo)
>        ("gfortran" ,gfortran)
>        ("icu4c" ,icu4c)
>        ("icedtea6" ,icedtea6 "jdk")
>        ("lapack" ,lapack)
>        ("libjpeg" ,libjpeg)
>        ("libpng" ,libpng)
>        ("libtiff" ,libtiff)
>        ("libxt" ,libxt)
>        ("pcre" ,pcre)
>        ("readline" ,readline)
>        ("zlib" ,zlib)))
>
> My guess is that somewhere, the triplet for IcedTea is silently filtered
> out.

Yes, you are right, it is filtered in ‘package-inputs-names’ in
"emacs/guix-main.scm".  The easiest fix would be the following

diff --git a/emacs/guix-main.scm b/emacs/guix-main.scm
index 8d3a881..636d524 100644
--- a/emacs/guix-main.scm
+++ b/emacs/guix-main.scm
@@ -245,7 +245,7 @@ Example:
 (define (package-inputs-names inputs)
   "Return a list of full names of the packages from package INPUTS."
   (filter-map (match-lambda
-               ((_ (? package? package))
+               ((_ (? package? package) _ ...)
                 (package-full-name package))
                (_ #f))
               inputs))

However, I think it would be better to have "icedtea6-1.13.7:jdk"
instead of "icedtea6-1.13.7" in the "Inputs".  This requires modifying
‘full-name->name+version’ procedure so that pressing such
"<name>-<version>:<out>" buttons will also work.

Thank you for noticing this.  The patch is attached.

>From ae9203234d5254a9cb6a8127d31e99289c605f7a Mon Sep 17 00:00:00 2001
From: Alex Kost <[email-masked]>
Date: Wed, 2 Sep 2015 17:57:58 +0300
Subject: [PATCH] emacs: Add support for "triplet" package inputs.

Fixes <http://bugs.gnu.org/21399>.

* emacs/guix-main.scm (full-name->name+version): Adjust to handle
  "name-version:output" string.
  (package-inputs-names): Support ("name" package "output") inputs.
---
 emacs/guix-main.scm | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/emacs/guix-main.scm b/emacs/guix-main.scm
index 8d3a881..623da88 100644
--- a/emacs/guix-main.scm
+++ b/emacs/guix-main.scm
@@ -71,7 +71,14 @@
 (define (list-maybe obj)
   (if (list? obj) obj (list obj)))
 
-(define full-name->name+version package-name->name+version)
+(define (full-name->name+version spec)
+  "Given package specification SPEC with or without output,
+return two values: name and version.  For example, for SPEC
+\"foo-0.9.1b:lib\", return \"foo\" and \"0.9.1b\"."
+  (let-values (((name version output)
+                (package-specification->name+version+output spec)))
+    (values name version)))
+
 (define (name+version->full-name name version)
   (string-append name "-" version))
 
@@ -247,6 +254,10 @@ Example:
   (filter-map (match-lambda
                ((_ (? package? package))
                 (package-full-name package))
+               ((_ (? package? package) output)
+                (make-package-specification (package-name package)
+                                            (package-version package)
+                                            output))
                (_ #f))
               inputs))
 
-- 
2.4.3