bug#26802: [PATCH 4/4] build: emacs: Fix `store-file->elisp-source-file'.

[Arun Isaac <arunisaac@systemreboot.net>]

This prevents a ".el.el" extension for source files with no version number in
their file name.

* guix/build/emacs-build-system.scm (store-file->elisp-source-file): Remove
  ".el" extension from file name before splitting to name and version.
---
 guix/build/emacs-build-system.scm | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/guix/build/emacs-build-system.scm b/guix/build/emacs-build-system.scm
index 44e8b0d31..25a3beaa2 100644
--- a/guix/build/emacs-build-system.scm
+++ b/guix/build/emacs-build-system.scm
@@ -47,10 +47,13 @@
 (define (store-file->elisp-source-file file)
   "Convert FILE, a store file name for an Emacs Lisp source file, into a file
 name that has been stripped of the hash and version number."
-  (let-values (((name version)
-                (package-name->name+version
-                 (strip-store-file-name file))))
-    (string-append name ".el")))
+  (let ((extension ".el"))
+    (let-values (((name version)
+                  (package-name->name+version
+                   (strip-store-file-name
+                    (string-drop-right
+                     file (string-length extension))))))
+      (string-append name extension))))
 
 (define* (unpack #:key source #:allow-other-keys)
   "Unpack SOURCE into the build directory.  SOURCE may be a compressed
-- 
2.12.2