build: emacs-build-system: Unify the installation directory.

This change aims to reduce the length of the EMACSLOADPATH environment
variable, which was found to cause issues such as
<https://bugs.gnu.org/38309>.

It should also enable discovery of newly installed packages without refreshing
the session's EMACSLOADPATH of the user profile (e.g., when launching Emacs
from the desktop manager application launcher), as discussed in
<https://bugs.gnu.org/38309>.

* guix/build/emacs-build-system.scm (%legacy-install-suffix): Rename to...
(%install-dir): ...this.
(%install-suffix): Remove variable.
(build): Adjust installation target directory.
(patch-el-files): Likewise.
(install): Likewise.
(move-doc): Likewise.
(make-autoloads): Likewise.

Signed-off-by: Clément Lassieur <clement@lassieur.org>

1 files changed, 16 insertions, 23 deletions

diff --git a/guix/build/emacs-build-system.scm b/guix/build/emacs-build-system.scm
index f0c41812f1..e2b792d3dc 100644
--- a/guix/build/emacs-build-system.scm
+++ b/guix/build/emacs-build-system.scm
@@ -40,11 +40,10 @@
 ;;
 ;; Code:
 
-;; Directory suffix where we install ELPA packages.  We avoid ".../elpa" as
-;; Emacs expects to find the ELPA repository 'archive-contents' file and the
-;; archive signature.
-(define %legacy-install-suffix "/share/emacs/site-lisp")
-(define %install-suffix (string-append %legacy-install-suffix "/guix.d"))
+;;; All the packages are installed directly under site-lisp, which means that
+;;; having that directory in the EMACSLOADPATH is enough to have them found by
+;;; Emacs.
+(define %install-dir "/share/emacs/site-lisp")
 
 ;; These are the default inclusion/exclusion regexps for the install phase.
 (define %default-include '("^[^/]*\\.el$" "^[^/]*\\.info$" "^doc/.*\\.info$"))
@@ -87,11 +86,10 @@ environment variable\n" source-directory)))
   "Compile .el files."
   (let* ((emacs (string-append (assoc-ref inputs "emacs") "/bin/emacs"))
          (out (assoc-ref outputs "out"))
-         (elpa-name-ver (store-directory->elpa-name-version out))
-         (el-dir (string-append out %install-suffix "/" elpa-name-ver)))
+         (site-lisp (string-append out %install-dir)))
     (setenv "SHELL" "sh")
     (parameterize ((%emacs emacs))
-      (emacs-byte-compile-directory el-dir))))
+      (emacs-byte-compile-directory site-lisp))))
 
 (define* (patch-el-files #:key outputs #:allow-other-keys)
   "Substitute the absolute \"/bin/\" directory with the right location in the
@@ -108,9 +106,7 @@ store in '.el' files."
       #:binary #t))
 
   (let* ((out (assoc-ref outputs "out"))
-         (elpa-name-ver (store-directory->elpa-name-version out))
-         (el-dir (string-append out %install-suffix "/" elpa-name-ver))
-
+         (site-lisp (string-append out %install-dir))
          ;; (ice-9 regex) uses libc's regexp routines, which cannot deal with
          ;; strings containing NULs.  Filter out such files.  TODO: Remove
          ;; this workaround when <https://bugs.gnu.org/30116> is fixed.
@@ -124,7 +120,7 @@ store in '.el' files."
              (error "patch-el-files: unable to locate " cmd-name))
            (string-append "\"" cmd "\"")))))
 
-    (with-directory-excursion el-dir
+    (with-directory-excursion site-lisp
       ;; Some old '.el' files (e.g., tex-buf.el in AUCTeX) are still
       ;; ISO-8859-1-encoded.
       (unless (false-if-exception (substitute-program-names))
@@ -175,15 +171,14 @@ parallel. PARALLEL-TESTS? is ignored when using a non-make TEST-COMMAND."
            (not (any (cut match-stripped-file "excluded" <>) exclude)))))
 
   (let* ((out (assoc-ref outputs "out"))
-         (elpa-name-ver (store-directory->elpa-name-version out))
-         (target-directory (string-append out %install-suffix "/" elpa-name-ver))
+         (site-lisp (string-append out %install-dir))
          (files-to-install (find-files source install-file?)))
     (cond
      ((not (null? files-to-install))
       (for-each
        (lambda (file)
          (let* ((stripped-file (string-drop file (string-length source)))
-                (target-file (string-append target-directory stripped-file)))
+                (target-file (string-append site-lisp stripped-file)))
            (format #t "`~a' -> `~a'~%" file target-file)
            (install-file file (dirname target-file))))
        files-to-install)
@@ -197,14 +192,12 @@ parallel. PARALLEL-TESTS? is ignored when using a non-make TEST-COMMAND."
 (define* (move-doc #:key outputs #:allow-other-keys)
   "Move info files from the ELPA package directory to the info directory."
   (let* ((out (assoc-ref outputs "out"))
-         (elpa-name-ver (store-directory->elpa-name-version out))
-         (el-dir (string-append out %install-suffix "/" elpa-name-ver))
-         (name-ver (strip-store-file-name out))
+         (site-lisp (string-append out %install-dir))
          (info-dir (string-append out "/share/info/"))
-         (info-files (find-files el-dir "\\.info$")))
+         (info-files (find-files site-lisp "\\.info$")))
     (unless (null? info-files)
       (mkdir-p info-dir)
-      (with-directory-excursion el-dir
+      (with-directory-excursion site-lisp
         (when (file-exists? "dir") (delete-file "dir"))
         (for-each (lambda (f)
                     (copy-file f (string-append info-dir "/" (basename f)))
@@ -216,11 +209,11 @@ parallel. PARALLEL-TESTS? is ignored when using a non-make TEST-COMMAND."
   "Generate the autoloads file."
   (let* ((emacs (string-append (assoc-ref inputs "emacs") "/bin/emacs"))
          (out (assoc-ref outputs "out"))
+         (site-lisp (string-append out %install-dir))
          (elpa-name-ver (store-directory->elpa-name-version out))
-         (elpa-name (package-name->name+version elpa-name-ver))
-         (el-dir (string-append out %install-suffix "/" elpa-name-ver)))
+         (elpa-name (package-name->name+version elpa-name-ver)))
     (parameterize ((%emacs emacs))
-      (emacs-generate-autoloads elpa-name el-dir))))
+      (emacs-generate-autoloads elpa-name site-lisp))))
 
 (define (emacs-package? name)
   "Check if NAME correspond to the name of an Emacs package."