Add :shadow parameter to package!

For to make replacing built-in packages easier.

core/core-packages.el

@@ -188,10 +188,20 @@ processed."
         (error "Failed to read any packages"))
     (dolist (package doom-packages)
       (cl-destructuring-bind
-          (name &key recipe disable ignore &allow-other-keys) package
+          (name &key recipe disable ignore shadow &allow-other-keys) package
         (unless ignore
           (if disable
               (cl-pushnew name doom-disabled-packages)
+            (when shadow
+              (straight-override-recipe (cons shadow '(:local-repo nil)))
+              (let ((site-load-path (copy-sequence doom--initial-load-path))
+                    lib)
+                (while (setq
+                        lib (locate-library (concat (symbol-name shadow) ".el")
+                                            nil site-load-path))
+                  (let ((lib (directory-file-name (file-name-directory lib))))
+                    (setq site-load-path (delete lib site-load-path)
+                          load-path (delete lib load-path))))))
             (when recipe
               (straight-override-recipe (cons name recipe)))
             (straight-register-package name)))))))
@@ -389,7 +399,7 @@ ones."
 ;;; Module package macros
 
 (cl-defmacro package!
-    (name &rest plist &key built-in recipe ignore _type _pin _disable)
+    (name &rest plist &key built-in recipe ignore _type _pin _disable _shadow)
   "Declares a package and how to install it (if applicable).
 
 This macro is declarative and does not load nor install packages. It is used to
@@ -426,6 +436,10 @@ Accepts the following properties:
    inform help commands like `doom/help-packages' that this is a built-in
    package. If set to 'prefer, the package will not be installed if it is
    already provided by Emacs.
+ :shadow PACKAGE
+   Informs Doom that this package is shadowing a built-in PACKAGE; the original
+   package will be removed from `load-path' to mitigate conflicts, and this new
+   package will satisfy any dependencies on PACKAGE in the future.
 
 Returns t if package is successfully registered, and nil if it was disabled
 elsewhere."

modules/lang/org/packages.el

@@ -1,12 +1,6 @@
 ;; -*- no-byte-compile: t; -*-
 ;;; lang/org/packages.el
 
-;; Prevent built-in Org from playing into the byte-compilation of
-;; `org-plus-contrib'.
-(when-let (orglib (locate-library "org" nil doom--initial-load-path))
-  (setq load-path (delete (substring (file-name-directory orglib) 0 -1)
-                          load-path)))
-
 ;; HACK A necessary hack because org requires a compilation step after being
 ;;      cloned, and during that compilation a org-version.el is generated with
 ;;      these two functions, which return the output of a 'git describe ...'
@@ -27,10 +21,11 @@
   :recipe (:host github
            :repo "emacs-straight/org-mode"
            :files ("*.el" "lisp/*.el" "contrib/lisp/*.el"))
-  :pin "220f2b0d93a6927eb673978c0042a1d4673e86aa")
-;; ...And prevent other packages from pulling org; org-plus-contrib satisfies
-;; the dependency already: https://github.com/raxod502/straight.el/issues/352
-(package! org :recipe (:local-repo nil))
+  :pin "220f2b0d93a6927eb673978c0042a1d4673e86aa"
+  ;; Prevents built-in Org from sneaking into the byte-compilation of
+  ;; `org-plus-contrib', and inform other packages that `org-mode' satisfies the
+  ;; `org' dependency: https://github.com/raxod502/straight.el/issues/352
+  :shadow 'org)
 
 (package! avy)
 (package! htmlize :pin "49205105898ba8993b5253beec55d8bddd820a70")