bug#47107: libtiff/fixed uses wrong version number in 'doc' output

[Ludovic Courtès]

Hi Leo,

Leo Famulari <leo@famulari.name> skribis:

> The grafted replacement of libtiff, libtiff/fixed, updates the package
> from version 4.1.0 to 4.2.0.
>
> However, the it does not adjust the #:configure-flags of the inherited
> package, which rely on the version number. 
>
> The result is directories named 'share/doc/libtiff-4.1.0' in the "doc"
> output of libtiff-4.2.0.

Instead of duplicating the ‘name’ and ‘arguments’ fields as done in
35b3ab8e5748d9911ae7a0189065d0c25392895b, one possibility is to change
the initial ‘libtiff’ like so:

diff --git a/gnu/packages/image.scm b/gnu/packages/image.scm
index 4f249b7622..44d2cac0fe 100644
--- a/gnu/packages/image.scm
+++ b/gnu/packages/image.scm
@@ -599,7 +599,8 @@ extracting icontainer icon files.")
     `(#:configure-flags (list (string-append "--with-docdir="
                                              (assoc-ref %outputs "doc")
                                              "/share/doc/"
-                                             ,name "-" ,version)
+                                             ,name "-"
+                                             ,(package-version this-package))
                               "--disable-static")))
    (inputs `(("zlib" ,zlib)
              ("libjpeg" ,libjpeg-turbo)))

WDTY?

Would it make sense to adopt this style also for
<https://issues.guix.gnu.org/47108> and
<https://issues.guix.gnu.org/47110>?

(Changing to this style should not trigger any rebuild because it
expands to the exact same thing.)

Thanks,
Ludo’.