[PATCH 1/4] emacs: Factorize searching for Emacs packages.

[Alex Kost]

* emacs/guix-emacs.el: (guix-emacs-directories): New procedure.
(guix-emacs-find-autoloads-in-directory): Rename to ...
(guix-emacs-find-autoloads): ... this.
(guix-emacs-load-autoloads): Replace with ...
(guix-emacs-autoload-packages): this.  New procedure.  At first, find a
list of directories with Emacs packages, then add them to 'load-path'
and finally, load autoloads.
(guix-emacs-load-autoloads-maybe): Rename to ...
(guix-emacs-autoload-packages-maybe): ... this.
* emacs/guix-backend.el (guix-after-repl-operation-hook): Adjust for the
renaming.
* doc/emacs.texi (Emacs Initial Setup): Likewise.
---
 doc/emacs.texi        |  2 +-
 emacs/guix-backend.el |  2 +-
 emacs/guix-emacs.el   | 70 +++++++++++++++++++++++++--------------------------
 3 files changed, 36 insertions(+), 38 deletions(-)

diff --git a/doc/emacs.texi b/doc/emacs.texi
index 92a9107..19dc87f 100644
--- a/doc/emacs.texi
+++ b/doc/emacs.texi
@@ -106,7 +106,7 @@ for the built-in Emacs package system (@pxref{Package 
Installation,,,
 emacs, The GNU Emacs Manual}).
 
 You can activate Emacs packages installed in your profile whenever you
-want using @address@hidden
+want using @address@hidden
 
 
 @node Emacs Package Management
diff --git a/emacs/guix-backend.el b/emacs/guix-backend.el
index 0736f85..04e5c1f 100644
--- a/emacs/guix-backend.el
+++ b/emacs/guix-backend.el
@@ -121,7 +121,7 @@ This REPL is used for receiving information only if
   "Hook run before executing an operation in Guix REPL.")
 
 (defvar guix-after-repl-operation-hook
-  '(guix-emacs-load-autoloads-maybe
+  '(guix-emacs-autoload-packages-maybe
     guix-repl-operation-success-message)
   "Hook run after executing successful operation in Guix REPL.")
 
diff --git a/emacs/guix-emacs.el b/emacs/guix-emacs.el
index 37a0bb2..5c32f2f 100644
--- a/emacs/guix-emacs.el
+++ b/emacs/guix-emacs.el
@@ -57,7 +57,7 @@ If PROFILE is nil, use `guix-user-profile'."
   (expand-file-name "share/emacs/site-lisp"
                     (or profile guix-user-profile)))
 
-(defun guix-emacs-find-autoloads-in-directory (directory)
+(defun guix-emacs-find-autoloads (directory)
   "Return a list of Emacs 'autoloads' files in DIRECTORY.
 The files in the list do not have extensions (.el, .elc)."
   (cl-remove-duplicates
@@ -76,45 +76,44 @@ The files in the list do not have extensions (.el, .elc)."
                       (not (file-directory-p file))))
                 (directory-files directory 'full-name nil 'no-sort)))
 
-(defun guix-emacs-find-autoloads (&optional profile)
-  "Return list of autoloads of Emacs packages installed in PROFILE.
+(defun guix-emacs-directories (&optional profile)
+  "Return a list of directories with Emacs packages installed in PROFILE.
 If PROFILE is nil, use `guix-user-profile'.
-Return nil if there are no emacs packages installed in PROFILE."
-  (let ((elisp-root-dir (guix-emacs-directory profile)))
-    (if (file-directory-p elisp-root-dir)
-        (let ((elisp-pkgs-dir (expand-file-name "guix.d" elisp-root-dir))
-              (root-autoloads (guix-emacs-find-autoloads-in-directory
-                               elisp-root-dir)))
-          (if (file-directory-p elisp-pkgs-dir)
-              (let ((pkgs-autoloads
-                     (cl-mapcan #'guix-emacs-find-autoloads-in-directory
-                                (guix-emacs-subdirs elisp-pkgs-dir))))
-                (append root-autoloads pkgs-autoloads))
-            root-autoloads))
-      (message "Directory '%s' does not exist." elisp-root-dir)
-      nil)))
+Return nil, if Emacs packages are not installed in PROFILE."
+  (let ((root-dir (guix-emacs-directory (or profile guix-user-profile))))
+    (when (file-directory-p root-dir)
+      (let* ((pkgs-dir  (expand-file-name "guix.d" root-dir))
+             (pkgs-dirs (when (file-directory-p pkgs-dir)
+                          (guix-emacs-subdirs pkgs-dir))))
+        (cons root-dir pkgs-dirs)))))
 
 ;;;###autoload
-(defun guix-emacs-load-autoloads (&optional profile)
-  "Load autoloads for Emacs packages installed in PROFILE.
+(defun guix-emacs-autoload-packages (&optional profile)
+  "Autoload Emacs packages installed in PROFILE.
 If PROFILE is nil, use `guix-user-profile'.
-Add autoloads directories to `load-path'."
+
+'Autoload' means add directories with Emacs packages to
+`load-path' and load 'autoloads' files matching
+`guix-emacs-autoloads-regexp'."
   (interactive (list (if (fboundp 'guix-profile-prompt)
                          (funcall 'guix-profile-prompt)
                        guix-user-profile)))
-  (let* ((autoloads     (guix-emacs-find-autoloads profile))
-         (new-autoloads (cl-nset-difference autoloads
-                                            guix-emacs-autoloads
-                                            :test #'string=)))
-    (dolist (file new-autoloads)
-      (cl-pushnew (directory-file-name (file-name-directory file))
-                  load-path
-                  :test #'string=)
-      (load file 'noerror))
-    (setq guix-emacs-autoloads
-          (append new-autoloads guix-emacs-autoloads))))
-
-(defun guix-emacs-load-autoloads-maybe ()
+  (let ((dirs (guix-emacs-directories (or profile guix-user-profile))))
+    (when dirs
+      (let* ((autoloads     (cl-mapcan #'guix-emacs-find-autoloads dirs))
+             (new-autoloads (cl-nset-difference autoloads
+                                                guix-emacs-autoloads
+                                                :test #'string=)))
+        (dolist (dir dirs)
+          (cl-pushnew (directory-file-name dir)
+                      load-path
+                      :test #'string=))
+        (dolist (file new-autoloads)
+          (load file 'noerror))
+        (setq guix-emacs-autoloads
+              (append new-autoloads guix-emacs-autoloads))))))
+
+(defun guix-emacs-autoload-packages-maybe ()
   "Load autoloads for Emacs packages if needed.
 See `guix-emacs-activate-after-operation' for details."
   (and guix-emacs-activate-after-operation
@@ -123,11 +122,10 @@ See `guix-emacs-activate-after-operation' for details."
        ;; packages can be installed to another profile, and the
        ;; following code will not work (i.e., the autoloads for this
        ;; profile will not be loaded).
-       (guix-emacs-load-autoloads guix-current-profile)))
+       (guix-emacs-autoload-packages guix-current-profile)))
 
 (when guix-package-enable-at-startup
-  (add-to-list 'load-path (guix-emacs-directory))
-  (guix-emacs-load-autoloads))
+  (guix-emacs-autoload-packages guix-user-profile))
 
 (provide 'guix-emacs)
 
-- 
2.6.3