From: Lars Ingebrigtsen <larsi@gnus.org>
Date: Tue, 19 Jan 2021 04:13:03 +0000 (+0100)
Subject: Don't infloop in comint-redirect-results-list-from-process
X-Git-Tag: emacs-28.0.90~4225
X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=43982a8f1017f709f78d5722796c266d4f72de05;p=emacs.git

Don't infloop in comint-redirect-results-list-from-process

* lisp/comint.el (comint-redirect-results-list-from-process):
Ensure forward progress (bug#45950).
---

diff --git a/lisp/comint.el b/lisp/comint.el
index 53153af7d27..e52d67d0e50 100644
--- a/lisp/comint.el
+++ b/lisp/comint.el
@@ -3863,7 +3863,11 @@ REGEXP-GROUP is the regular expression group in REGEXP to use."
 	(push (buffer-substring-no-properties
                (match-beginning regexp-group)
                (match-end regexp-group))
-              results))
+              results)
+        (when (zerop (length (match-string 0)))
+          ;; If the regexp can be empty (for instance, "^.*$"), we
+          ;; don't advance, so ensure forward progress.
+	  (forward-line 1)))
       (nreverse results))))
 
 ;; Converting process modes to use comint mode