From: Eshel Yaron <me@eshelyaron.com>
Date: Sat, 10 Feb 2024 16:30:27 +0000 (+0100)
Subject: ; Fix 'thing-at-point' edge case involving overlapping matches
X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=1fc1f93ab088c3aaefa05eed75c2053449dc0db6;p=emacs.git

; Fix 'thing-at-point' edge case involving overlapping matches

* lisp/thingatpt.el (thing-at-point-looking-at): When finding a match
that ends before point, continue searching from the beginning of that
match, not its end, in case the match we're looking is overlapping with
this one.
* test/lisp/thingatpt-tests.el
(thing-at-point-looking-at-overlapping-matches): New test.
---

diff --git a/lisp/thingatpt.el b/lisp/thingatpt.el
index b532bafff82..83ddc640d35 100644
--- a/lisp/thingatpt.el
+++ b/lisp/thingatpt.el
@@ -621,13 +621,14 @@ Optional argument DISTANCE limits search for REGEXP forward and
 back from point."
   (let* ((old (point))
          (beg (if distance (max (point-min) (- old distance)) (point-min)))
-         (end (and distance (min (point-max) (+ old distance))))
+         (end (if distance (min (point-max) (+ old distance))))
          prev match)
     (save-excursion
       (goto-char beg)
       (while (and (setq prev (point)
                         match (re-search-forward regexp end t))
                   (< (match-end 0) old))
+        (goto-char (match-beginning 0))
         ;; Avoid inflooping when `regexp' matches the empty string.
         (unless (< prev (point)) (forward-char))))
     (and match (<= (match-beginning 0) old (match-end 0)))))
diff --git a/test/lisp/thingatpt-tests.el b/test/lisp/thingatpt-tests.el
index 56bc4fdc9dc..e50738f1122 100644
--- a/test/lisp/thingatpt-tests.el
+++ b/test/lisp/thingatpt-tests.el
@@ -182,6 +182,13 @@ position to retrieve THING.")
       (should (thing-at-point-looking-at "2abcd"))
       (should (equal (match-data) m2)))))
 
+(ert-deftest thing-at-point-looking-at-overlapping-matches ()
+  (with-temp-buffer
+    (insert "foo.bar.baz")
+    (goto-char (point-max))
+    (should (thing-at-point-looking-at "[a-z]+\\.[a-z]+"))
+    (should (string= "bar.baz" (match-string 0)))))
+
 (ert-deftest test-symbol-thing-1 ()
   (with-temp-buffer
     (insert "foo bar zot")