bug#58367: `package-install-file' rejects some .tar files (tentative patch)

[Richard Hopkins <emacs@unbit.co.uk>]

On 2022-10-08 17:25, Stefan Monnier wrote:
> Thanks for the tarballs for the tests, they were very helpful.
> The patch also pointed in the right direction.
> 
> I installed the patch below (plus regression tests) into `master`.

Great, thanks for taking a look at this and also fixing the top level
lookup for v7-withsub-0.1.tar.  I've pulled the latest changes and all
the original tar files now install.

I've managed to get the ustar-withsub-0.1 to install from a directory
and include the sub directories by using `copy-directory' instead of
only copying the .el files in the top level.  As more inspiration...

diff --git a/lisp/emacs-lisp/package.el b/lisp/emacs-lisp/package.el
index d619142d64..4144a12718 100644
--- a/lisp/emacs-lisp/package.el
+++ b/lisp/emacs-lisp/package.el
@@ -947,14 +947,10 @@ package-unpack
           (pkg-dir (expand-file-name dirname package-user-dir)))
      (pcase (package-desc-kind pkg-desc)
        ('dir
-       (make-directory pkg-dir t)
         (let ((file-list
-              (directory-files
-               default-directory 'full "\\`[^.].*\\.el\\'" 'nosort)))
-         (dolist (source-file file-list)
-           (let ((target-el-file
-                  (expand-file-name (file-name-nondirectory 
source-file) pkg-dir)))
-             (copy-file source-file target-el-file t)))
+              (directory-files-recursively
+               default-directory "." t)))
+         (copy-directory default-directory pkg-dir nil t 
'copy-contents)
           ;; Now that the files have been installed, this package is
           ;; indistinguishable from a `tar' or a `single'. Let's make
           ;; things simple by ensuring we're one of them.