org-element-cache-map: Fix edge case when we move to not-yet-cached element

* lisp/org-element.el (org-element-cache-map): Make sure that there is
always a cached element where we move START position.
* testing/lisp/test-org-element.el (test-org-element/cache-map): New
test.

Co-authored-by: Morgan Smith <Morgan.J.Smith@outlook.com>

lisp/org-element.el

@@ -8292,8 +8292,11 @@ the cache."
                               ;; Reached LIMIT-COUNT.  Abort.
                               (when (and limit-count
                                          (>= count-predicate-calls-match
-                                             limit-count))
-                                (cache-walk-abort)))
+                                            limit-count))
+                                (cache-walk-abort))
+                              ;; Make sure that we have a cached
+                              ;; element at the new STAR.
+                              (when start (element-match-at-point)))
                             ;; Check if the buffer or cache has been modified.
                             (unless (org-with-base-buffer nil
                                       (and (eq modified-tic org-element--cache-change-tic)

lisp/org.el

@@ -7332,13 +7332,12 @@ When REMOVE is non-nil, remove the subtree from the clipboard."
 	      ((looking-at-p org-outline-regexp-bol) (org-outline-level))))
 	    (previous-level
 	     (save-excursion
-	       (org-previous-visible-heading 1)
+	       (unless (org-at-heading-p) (org-previous-visible-heading 1))
 	       (if (org-at-heading-p) (org-outline-level) 1)))
 	    (next-level
 	     (save-excursion
-	       (if (org-at-heading-p) (org-outline-level)
-	         (org-next-visible-heading 1)
-	         (if (org-at-heading-p) (org-outline-level) 1))))
+	       (org-next-visible-heading 1)
+	       (if (org-at-heading-p) (org-outline-level) 1)))
 	    (new-level (or force-level (max previous-level next-level)))
 	    (shift (if (or (= old-level -1)
 			   (= new-level -1)

testing/lisp/test-org-element.el

@@ -4983,6 +4983,18 @@ Text
 
 
 ;;; Test Cache.
+(ert-deftest test-org-element/cache-map ()
+  "Test `org-element-cache-map'."
+  (org-test-with-temp-text "* headline\n:DRAWER:\nparagraph\n:END:\n* headline 2"
+    (should
+     (equal
+      '(org-data headline section drawer paragraph headline)
+      (org-element-cache-map #'car :granularity 'element))))
+  (should
+   (equal
+    '(org-data headline section drawer paragraph)
+    (org-test-with-temp-text "* headline\n:DRAWER:\nparagraph\n:END:"
+      (org-element-cache-map #'car :granularity 'element)))))
 
 (ert-deftest test-org-element/cache ()
   "Test basic expectations and common pitfalls for cache."

testing/lisp/test-org.el

@@ -9372,6 +9372,24 @@ CLOSED: %s
 	  (org-test-with-temp-text "* H1\n<point>\n** H2"
 	    (org-paste-subtree nil "* Text")
 	    (buffer-string))))
+  ;; When point is on heading at bol, insert before
+  (should
+   (equal "* Text\n* H1\n** H2"
+	  (org-test-with-temp-text "<point>* H1\n** H2"
+	    (org-paste-subtree nil "*** Text")
+	    (buffer-string))))
+  ;; When point is on heading but not at bol, use smallest level among
+  ;; current heading and next, inserting before the next heading.
+  (should
+   (equal "* H1\ncontents\n** Text\n** H2"
+	  (org-test-with-temp-text "* H1<point>\ncontents\n** H2"
+	    (org-paste-subtree nil "*** Text")
+	    (buffer-string))))
+  (should
+   (equal "*** H1\ncontents\n*** Text\n* H2"
+	  (org-test-with-temp-text "*** H1<point>\ncontents\n* H2"
+	    (org-paste-subtree nil "* Text")
+	    (buffer-string))))
   ;; When on an empty heading, after the stars, deduce the new level
   ;; from the number of stars.
   (should