add separately-packaged built-in packages to ${elpa:Depends}

1 files changed, 18 insertions, 5 deletions

diff --git a/dh-elpa.el b/dh-elpa.el
index 094913e..8017851 100644
--- a/dh-elpa.el
+++ b/dh-elpa.el
@@ -172,11 +172,24 @@ such a case."
   "Filter a list of package.el deps DEPS for Debian.
 
 Remove packages that are maintained outside of the elpa-*
-namespace in Debian, plus Emacs itself."
-  (let ((non-elpa (list 'emacs 's 'dash 'yasnippet)))
-    (cl-remove-if (lambda (dep)
-                    (or (memq (car dep) non-elpa)
-                        (package-built-in-p (car dep))))
+namespace in Debian, plus Emacs itself.
+
+Also remove built-in packages, except those built-in packages
+that are also packaged separately in Debian.
+
+These are packaged separately for two reasons:
+
+- it allows us to provide newer versions than those in Emacs core
+
+- it permits use of addons with older versions of Emacs, for
+  which the dependency is not yet a built-in package."
+  (let ((non-elpa (list 'emacs 's 'dash 'yasnippet))
+        (packaged-separately (list 'let-alist 'seq)))
+    (cl-remove-if (lambda (dep) (let ((pkg (car dep)))
+                      (or (memq pkg non-elpa)
+                          (and
+                           (package-built-in-p pkg)
+                           (not (memq pkg packaged-separately))))))
                   deps)))
 
 (defun dhelpa-filter-pkg-desc (desc)