[elpa] elpa-admin 9731033 204/357: Use symbolic links for core packages

[Stefan Monnier]

branch: elpa-admin
commit 97310334e317dfe992241e1f6667704f5341c28b
Author: Thomas Fitzsimmons <fitzsim@fitzsim.org>
Commit: Thomas Fitzsimmons <fitzsim@fitzsim.org>

    Use symbolic links for core packages
    
    * admin/archive-contents.el (archive--process-simple-package):
    Copy file if it is a symlink to prevent deletion of target source
    file.
    (archive--core-package-link-file): Rename from
    archive--core-package-copy-file.  Create symbolic links for core
    files.
    (archive--core-package-link-directory): Rename from
    archive--core-package-copy-directory.  Call
    archive--core-package-link-file.
    (archive--core-package-sync): Change message to indicate linking.
    Call archive--core-package-link-file.
---
 admin/archive-contents.el | 29 +++++++++++++++++------------
 1 file changed, 17 insertions(+), 12 deletions(-)

diff --git a/admin/archive-contents.el b/admin/archive-contents.el
index 74e473e..feb646a 100755
--- a/admin/archive-contents.el
+++ b/admin/archive-contents.el
@@ -207,8 +207,9 @@ PKG is the name of the package and DIR is the directory 
where it is."
   "Deploy the contents of DIR into the archive as a simple package.
 Rename DIR/PKG.el to PKG-VERS.el, delete DIR, and return the descriptor."
   ;; Write DIR/foo.el to foo-VERS.el and delete DIR
-  (rename-file (expand-file-name (concat pkg ".el") dir)
-              (concat pkg "-" vers ".el"))
+  (let ((src (expand-file-name (concat pkg ".el") dir)))
+    (funcall (if (file-symlink-p src) #'copy-file #'rename-file)
+            src (concat pkg "-" vers ".el")))
   ;; Add the content of the ChangeLog.
   (let ((cl (expand-file-name "ChangeLog" dir)))
     (with-current-buffer (find-file-noselect (concat pkg "-" vers ".el"))
@@ -645,9 +646,9 @@ version control nor listed in EXTERNALS-LIST."
   "Return non-nil if DEST is an empty variant."
   (member dest (list "" "." nil)))
 
-(defun archive--core-package-copy-file
+(defun archive--core-package-link-file
     (source dest emacs-repo-root package-root exclude-regexp)
-  "Copy file from SOURCE to DEST ensuring subdirectories."
+  "Link file from SOURCE to DEST ensuring subdirectories."
   (unless (string-match-p exclude-regexp source)
     (let* ((absolute-package-file-name
             (expand-file-name dest package-root))
@@ -656,14 +657,18 @@ version control nor listed in EXTERNALS-LIST."
            (directory (file-name-directory absolute-package-file-name)))
       (unless (file-directory-p directory)
         (make-directory directory t))
-      (copy-file absolute-core-file-name absolute-package-file-name))
+      (condition-case nil
+         (make-symbolic-link absolute-core-file-name
+                             absolute-package-file-name t)
+       (file-error
+        (copy-file absolute-core-file-name absolute-package-file-name))))
     (message "  %s -> %s" source (if (archive--core-package-empty-dest-p dest)
                                      (file-name-nondirectory source)
                                    dest))))
 
-(defun archive--core-package-copy-directory
+(defun archive--core-package-link-directory
     (source dest emacs-repo-root package-root exclude-regexp)
-  "Copy directory files from SOURCE to DEST ensuring subdirectories."
+  "Link directory files from SOURCE to DEST ensuring subdirectories."
   (let ((stack (list source))
         (base source)
         (absolute-source))
@@ -678,12 +683,12 @@ version control nor listed in EXTERNALS-LIST."
                (source-sans-base (substring source (length base)))
                (package-file-name
                 (if (archive--core-package-empty-dest-p dest)
-                    ;; Copy to root with it's original filename.
+                    ;; Link to root with its original filename.
                     source-sans-base
                   (concat
                    ;; Prepend the destination, allowing for directory rename.
                    (file-name-as-directory dest) source-sans-base))))
-          (archive--core-package-copy-file
+          (archive--core-package-link-file
            source package-file-name
            emacs-repo-root package-root exclude-regexp))))))
 
@@ -711,16 +716,16 @@ version control nor listed in EXTERNALS-LIST."
              ;; Files may be just a string, normalize.
              (list file-patterns)
            file-patterns))))
-    (message "Copying files for package: %s" name)
+    (message "Linking files for package: %s" name)
     (when (file-directory-p package-root)
       (delete-directory package-root t))
     (make-directory package-root t)
     (dolist (file-pattern file-patterns)
       (pcase-let* ((`(,file . ,dest) file-pattern))
         (if (file-directory-p (expand-file-name file emacs-repo-root))
-            (archive--core-package-copy-directory
+            (archive--core-package-link-directory
              file dest emacs-repo-root package-root exclude-regexp)
-          (archive--core-package-copy-file
+          (archive--core-package-link-file
            file dest emacs-repo-root package-root exclude-regexp))))))
 
 (defun archive-add/remove/update-externals ()