Fix `org-babel-detangle' handling of false positives

* lisp/ob-tangle.el (org-babel-detangle): Handle false positive
matches of `org-link-bracket-re'.

* testing/examples/babel.el: New file for Babel detangle false
positive test.

* testing/examples/babel.org (detangle): Add detangle/false positive
example.

* testing/lisp/test-ob-tangle.el (ob-tangle/detangle-false-positive):
Add test for detangle false positive.

lisp/ob-tangle.el

@@ -516,14 +516,16 @@ which enable the original code blocks to be found."
     (goto-char (point-min))
     (let ((counter 0) new-body end)
       (while (re-search-forward org-link-bracket-re nil t)
-        (when (re-search-forward
-	       (concat " " (regexp-quote (match-string 2)) " ends here"))
-          (setq end (match-end 0))
-          (forward-line -1)
-          (save-excursion
-	    (when (setq new-body (org-babel-tangle-jump-to-org))
-	      (org-babel-update-block-body new-body)))
-          (setq counter (+ 1 counter)))
+        (if (and (match-string 2)
+		 (re-search-forward
+		  (concat " " (regexp-quote (match-string 2)) " ends here") nil t))
+	    (progn (setq end (match-end 0))
+		   (forward-line -1)
+		   (save-excursion
+		     (when (setq new-body (org-babel-tangle-jump-to-org))
+		       (org-babel-update-block-body new-body)))
+		   (setq counter (+ 1 counter)))
+	  (setq end (point)))
         (goto-char end))
       (prog1 counter (message "Detangled %d code blocks" counter)))))
 

testing/examples/babel.el

@@ -0,0 +1,5 @@
+(string-match-p "^#[[:digit:]]+$" "#123")
+
+;; [[id:73115FB0-6565-442B-BB95-50195A499EF4][detangle:1]]
+;; detangle changes
+;; linked content to detangle:1 ends here

testing/examples/babel.org

@@ -488,3 +488,16 @@ nil
 #+BEGIN_SRC emacs-lisp :output-dir xxx :file foo.bar
 nil
 #+END_SRC
+* detangle
+** false positive
+The =[[= causes a false positive which ~org-babel-detangle~ should handle properly
+#+begin_src emacs-lisp :tangle yes
+(string-match-p "^#[[:digit:]]+$" "#123")
+#+end_src
+** linked content to detangle
+:PROPERTIES:
+:ID:       73115FB0-6565-442B-BB95-50195A499EF4
+:END:
+#+begin_src emacs-lisp :tangle yes :comments link
+  ;; detangle
+#+end_src

testing/lisp/test-ob-tangle.el

@@ -25,6 +25,8 @@
 
 ;;; Code:
 
+(require 'subr-x)
+
 ;; TODO
 ;; (ert-deftest ob-tangle/noweb-on-tangle ()
 ;;   "Noweb header arguments tangle correctly.
@@ -380,6 +382,15 @@ another block
 		    (org-split-string (buffer-string))))
 	      (delete-file file))))))
 
+(ert-deftest ob-tangle/detangle-false-positive ()
+  "Test handling of false positive link during detangle."
+  (org-test-in-example-file (expand-file-name "babel.el" org-test-example-dir)
+    (org-babel-detangle)
+    (org-test-at-id "73115FB0-6565-442B-BB95-50195A499EF4"
+    (org-babel-next-src-block)
+    (should (equal (string-trim (org-element-property :value (org-element-at-point)))
+		   ";; detangle changes")))))
+
 (provide 'test-ob-tangle)
 
 ;;; test-ob-tangle.el ends here