org-export: Add an optional argument to previous an next elements getters

* contrib/lisp/org-export.el (org-export-get-previous-element,
  org-export-get-next-element): Change signature.
* testing/lisp/test-org-export.el: Add tests.

diff --git a/contrib/lisp/org-export.el b/contrib/lisp/org-export.el
index 00a5ef5..0a44e4d 100644 (file)
--- a/contrib/lisp/org-export.el
+++ b/contrib/lisp/org-export.el
@@ -4627,53 +4627,74 @@ OBJECT is either a `table-cell' or `table-element' type object."
                (not (eq (org-element-type parent) 'table))))
     parent))
 
-(defun org-export-get-previous-element (blob info)
+(defun org-export-get-previous-element (blob info &optional n)
   "Return previous element or object.
+
 BLOB is an element or object.  INFO is a plist used as
 a communication channel.  Return previous exportable element or
-object, a string, or nil."
-  (let (prev)
+object, a string, or nil.
+
+When optional argument N is a positive integer, return a list
+containing up to N siblings before BLOB, from closest to
+farthest."
+  (when (and n (not (wholenump n))) (setq n nil))
+  (let ((siblings
+        ;; An object can belong to the contents of its parent or
+        ;; to a secondary string.  We check the latter option
+        ;; first.
+        (let ((parent (org-export-get-parent blob)))
+          (or (and (not (memq (org-element-type blob)
+                              org-element-all-elements))
+                   (let ((sec-value
+                          (org-element-property
+                           (cdr (assq (org-element-type parent)
+                                      org-element-secondary-value-alist))
+                           parent)))
+                     (and (memq blob sec-value) sec-value)))
+              (org-element-contents parent))))
+       prev)
     (catch 'exit
       (mapc (lambda (obj)
-             (cond ((eq obj blob) (throw 'exit prev))
-                   ((memq obj (plist-get info :ignore-list)))
-                   (t (setq prev obj))))
-           ;; An object can belong to the contents of its parent or
-           ;; to a secondary string.  We check the latter option
-           ;; first.
-           (let ((parent (org-export-get-parent blob)))
-             (or (and (not (memq (org-element-type blob)
-                                 org-element-all-elements))
-                      (let ((sec-value
-                             (org-element-property
-                              (cdr (assq (org-element-type parent)
-                                         org-element-secondary-value-alist))
-                              parent)))
-                        (and (memq blob sec-value) sec-value)))
-                 (org-element-contents parent)))))))
-
-(defun org-export-get-next-element (blob info)
+             (cond ((memq obj (plist-get info :ignore-list)))
+                   ((null n) (throw 'exit obj))
+                   ((zerop n) (throw 'exit (nreverse prev)))
+                   (t (decf n) (push obj prev))))
+           (cdr (memq blob (reverse siblings))))
+      (nreverse prev))))
+
+(defun org-export-get-next-element (blob info &optional n)
   "Return next element or object.
+
 BLOB is an element or object.  INFO is a plist used as
 a communication channel.  Return next exportable element or
-object, a string, or nil."
-  (catch 'found
-    (mapc (lambda (obj)
-           (unless (memq obj (plist-get info :ignore-list))
-             (throw 'found obj)))
-         ;; An object can belong to the contents of its parent or to
-         ;; a secondary string.  We check the latter option first.
-         (let ((parent (org-export-get-parent blob)))
-           (or (and (not (memq (org-element-type blob)
-                               org-element-all-objects))
-                    (let ((sec-value
-                           (org-element-property
-                            (cdr (assq (org-element-type parent)
-                                       org-element-secondary-value-alist))
-                            parent)))
-                      (cdr (memq blob sec-value))))
-               (cdr (memq blob (org-element-contents parent))))))
-    nil))
+object, a string, or nil.
+
+When optional argument N is a positive integer, return a list
+containing up to N siblings after BLOB, from closest to
+farthest."
+  (when (and n (not (wholenump n))) (setq n nil))
+  (let ((siblings
+        ;; An object can belong to the contents of its parent or to
+        ;; a secondary string.  We check the latter option first.
+        (let ((parent (org-export-get-parent blob)))
+          (or (and (not (memq (org-element-type blob)
+                              org-element-all-objects))
+                   (let ((sec-value
+                          (org-element-property
+                           (cdr (assq (org-element-type parent)
+                                      org-element-secondary-value-alist))
+                           parent)))
+                     (cdr (memq blob sec-value))))
+              (cdr (memq blob (org-element-contents parent))))))
+       next)
+    (catch 'exit
+      (mapc (lambda (obj)
+             (cond ((memq obj (plist-get info :ignore-list)))
+                   ((null n) (throw 'exit obj))
+                   ((zerop n) (throw 'exit (nreverse next)))
+                   (t (decf n) (push obj next))))
+           siblings)
+      (nreverse next))))
 
 
 ;;;; Translation

diff --git a/testing/lisp/test-org-export.el b/testing/lisp/test-org-export.el
index dc67059..3693978 100644 (file)
--- a/testing/lisp/test-org-export.el
+++ b/testing/lisp/test-org-export.el
@@ -2211,7 +2211,16 @@ Another text. (ref:text)
        (org-test-with-parsed-data "#+CAPTION: a =verb=\nParagraph"
         (org-element-type
          (org-export-get-next-element
-          (org-element-map tree 'plain-text 'identity info t nil t) info))))))
+          (org-element-map tree 'plain-text 'identity info t nil t) info)))))
+  ;; With optional argument N, return a list containing up to
+  ;; N following elements.
+  (should
+   (equal
+    '(bold code)
+    (org-test-with-parsed-data "_a_ /b/ *c* ~d~"
+      (mapcar 'car
+             (org-export-get-next-element
+              (org-element-map tree 'italic 'identity info t) info 2))))))
 
 (ert-deftest test-org-export/get-previous-element ()
   "Test `org-export-get-previous-element' specifications."
@@ -2253,7 +2262,15 @@ Another text. (ref:text)
        (org-test-with-parsed-data "#+CAPTION: =verb= a\nParagraph"
         (org-element-type
          (org-export-get-previous-element
-          (org-element-map tree 'plain-text 'identity info t nil t) info))))))
+          (org-element-map tree 'plain-text 'identity info t nil t) info)))))
+  ;; With optional argument N, return a list containing up to
+  ;; N previous elements.
+  (should
+   (equal '(bold italic)
+         (org-test-with-parsed-data "_a_ /b/ *c* ~d~"
+           (mapcar 'car
+                   (org-export-get-previous-element
+                    (org-element-map tree 'code 'identity info t) info 2))))))
 
 
 (provide 'test-org-export)