Remove `org-export-link-as-file'

* lisp/ol.el (org-link-parameters): Remove reference to the function.
* lisp/ox.el (org-export-link-as-file): Remove function.
* testing/lisp/test-ox.el (test-org-export/link-as-file): Remove test.

The current implementation is not satisfactory, and not useful in the
code base. Using a pre-export hook turning custom link type into
"file" is enough for now. See "attachement" links for an example.

etc/ORG-NEWS

@@ -186,11 +186,11 @@ When this startup option is set, display headings as numeroted.
 
 Use =#+startup: nonum= to turn this off.
 
-*** New tools for custom links
+*** New tool for custom links
 
-Org provides two new tools, ~org-link-open-as-file~ and
-~org-export-link-as-file~, useful when defining new link types similar
-to "file"-type links.  See docstring for details.
+Org provides a new tool ~org-link-open-as-file~, useful when defining
+new link types similar to "file"-type links.  See docstring for
+details.
 
 *** =ob-clojure.el= supports inf-clojure.el and ClojureScript evaluation
 

lisp/ol.el

@@ -112,10 +112,6 @@ below.
   - the export back-end,
   - the export communication channel, as a plist.
 
-  If the new link type is meant to be exported as a \"file\"-link
-  (or as an image), consider using `org-export-link-as-file',
-  either as an helper function, or as a value for this parameter.
-
   When nil, export for that type of link is delegated to the
   back-end.
 

lisp/org-attach.el

@@ -42,7 +42,6 @@
 (declare-function dired-dwim-target-directory "dired-aux")
 (declare-function org-element-property "org-element" (property element))
 (declare-function org-element-type "org-element" (element))
-(declare-function org-export-link-as-file "org-export" (path description backend info))
 
 (defgroup org-attach nil
   "Options concerning attachments in Org mode."

lisp/ox.el

@@ -4185,21 +4185,6 @@ meant to be translated with `org-export-data' or alike."
 
 (org-define-error 'org-link-broken "Unable to resolve link; aborting")
 
-(defun org-export-link-as-file (path description backend info)
-  "Pretend PATH is a file name, and export it.
-
-DESCRIPTION, when non-nil, is the description of the link, as
-a string.  BACKEND is the symbol representing the back-end used
-for export.  INFO is the communication channel, as a plist.
-
-This function is meant to be used as a possible tool for
-`:export' property in `org-link-parameters'."
-  (org-export-data-with-backend
-   (org-element-parse-secondary-string
-    (org-link-make-string (concat "file:" path) description) '(link))
-   backend
-   info))
-
 (defun org-export-custom-protocol-maybe (link desc backend &optional info)
   "Try exporting LINK object with a dedicated function.
 

testing/lisp/test-ox.el

@@ -2965,32 +2965,6 @@ Para2"
 
 ;;; Links
 
-(ert-deftest test-org-export/link-as-file ()
-  "Test `org-export-link-as-file' specifications."
-  ;; Export path as a "file"-type link.
-  (should
-   (equal "success"
-	  (let ((backend
-		 (org-export-create-backend
-		  :name 'test
-		  :transcoders
-		  '((link . (lambda (l _c _i)
-			      (if (equal "file" (org-element-property :type l))
-				  "success"
-				"failure")))))))
-	    (org-export-link-as-file "foo.org" nil backend nil))))
-  ;; Exported path handles "file"-type specific properties,
-  ;; e.g., :search-option.
-  (should
-   (equal "bar"
-	  (let ((backend
-		 (org-export-create-backend
-		  :name 'test
-		  :transcoders
-		  '((link . (lambda (l _c _i)
-			      (org-element-property :search-option l)))))))
-	    (org-export-link-as-file "foo.org::bar" nil backend nil)))))
-
 (ert-deftest test-org-export/custom-protocol-maybe ()
   "Test `org-export-custom-protocol-maybe' specifications."
   (should