compat: Add `org-string-distance'

* lisp/ob-core.el (org-babel-edit-distance): Rename function
`org-string-distance' and move it to "org-compat.el".
(org-babel-check-src-block): Use `org-string-distance' instead.
* lisp/org-compat.el: Add `org-string-distance' for a future
deprecation in favor of `string-distance'.

lisp/ob-core.el

@@ -809,27 +809,6 @@ arguments and pop open the results in a preview buffer."
 	 expanded (concat "*Org-Babel Preview " (buffer-name) "[ " lang " ]*"))
       expanded)))
 
-(defun org-babel-edit-distance (s1 s2)
-  "Return the edit (levenshtein) distance between strings S1 S2."
-  (let* ((l1 (length s1))
-	 (l2 (length s2))
-	 (dist (vconcat (mapcar (lambda (_) (make-vector (1+ l2) nil))
-				(number-sequence 1 (1+ l1)))))
-	 (in (lambda (i j) (aref (aref dist i) j))))
-    (setf (aref (aref dist 0) 0) 0)
-    (dolist (j (number-sequence 1 l2))
-      (setf (aref (aref dist 0) j) j))
-    (dolist (i (number-sequence 1 l1))
-      (setf (aref (aref dist i) 0) i)
-      (dolist (j (number-sequence 1 l2))
-	(setf (aref (aref dist i) j)
-	      (min
-	       (1+ (funcall in (1- i) j))
-	       (1+ (funcall in i (1- j)))
-	       (+ (if (equal (aref s1 (1- i)) (aref s2 (1- j))) 0 1)
-		  (funcall in (1- i) (1- j)))))))
-    (funcall in l1 l2)))
-
 (defun org-babel-combine-header-arg-lists (original &rest others)
   "Combine a number of lists of header argument names and arguments."
   (let ((results (copy-sequence original)))
@@ -858,7 +837,7 @@ arguments and pop open the results in a preview buffer."
 				   (match-string 4))))))
       (dolist (name names)
 	(when (and (not (string= header name))
-		   (<= (org-babel-edit-distance header name) too-close)
+		   (<= (org-string-distance header name) too-close)
 		   (not (member header names)))
 	  (error "Supplied header \"%S\" is suspiciously close to \"%S\""
 		 header name))))

lisp/org-compat.el

@@ -119,6 +119,32 @@ extension beyond end of line was not controllable."
   (when (fboundp 'set-face-extend)
     (mapc (lambda (f) (set-face-extend f extend-p)) faces)))
 
+(if (fboundp 'string-distance)
+    (defalias 'org-string-distance 'string-distance)
+  (defun org-string-distance (s1 s2)
+    "Return the edit (levenshtein) distance between strings S1 S2."
+    (let* ((l1 (length s1))
+	   (l2 (length s2))
+	   (dist (vconcat (mapcar (lambda (_) (make-vector (1+ l2) nil))
+				  (number-sequence 1 (1+ l1)))))
+	   (in (lambda (i j) (aref (aref dist i) j))))
+      (setf (aref (aref dist 0) 0) 0)
+      (dolist (j (number-sequence 1 l2))
+        (setf (aref (aref dist 0) j) j))
+      (dolist (i (number-sequence 1 l1))
+        (setf (aref (aref dist i) 0) i)
+        (dolist (j (number-sequence 1 l2))
+	  (setf (aref (aref dist i) j)
+	        (min
+	         (1+ (funcall in (1- i) j))
+	         (1+ (funcall in i (1- j)))
+	         (+ (if (equal (aref s1 (1- i)) (aref s2 (1- j))) 0 1)
+		    (funcall in (1- i) (1- j)))))))
+      (funcall in l1 l2))))
+
+(define-obsolete-function-alias 'org-babel-edit-distance 'org-string-distance
+  "Org 9.5")
+
 
 ;;; Emacs < 26.1 compatibility