(comint-send-input): When waiting for echoed input, don't save the

expected end position in `echo-end', so that things work properly even
if the buffer is modified elsewhere at the same time [this happens if
`comint-truncate-buffer' is used].

2 files changed, 32 insertions, 20 deletions

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 9436d6bb49b..1292cc2cfbf 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,10 @@
+2001-09-11  Miles Bader  <miles@gnu.org>
+
+        * comint.el (comint-send-input): When waiting for echoed input,
+        don't save the expected end position in `echo-end', so that things
+        work properly even if the buffer is modified elsewhere at the same
+        time [this happens if `comint-truncate-buffer' is used].
+
 2001-09-11  Gerd Moellmann  <gerd@gnu.org>
 
         * textmodes/outline.el (outline-mode): Use `^' and a shy group
diff --git a/lisp/comint.el b/lisp/comint.el
index 24ffe55ed71..71d0cae28ea 100644
--- a/lisp/comint.el
+++ b/lisp/comint.el
@@ -1469,26 +1469,31 @@ Similarly for Soar, Scheme, etc."
           (funcall comint-input-sender proc input)
 
           ;; Optionally delete echoed input (after checking it).
-          (if comint-process-echoes
-              (let* ((echo-len (- comint-last-input-end
-                                  comint-last-input-start))
-                     (echo-end (+ comint-last-input-end echo-len)))
-                ;; Wait for all input to be echoed:
-                (while (and (accept-process-output proc)
-                            (> echo-end (point-max))
-                            (= 0 (compare-buffer-substrings
-                                  nil comint-last-input-start
-                                  (- (point-max) echo-len)
-                                  ;; Above difference is equivalent to
-                                  ;; (+ comint-last-input-start
-                                  ;;    (- (point-max) comint-last-input-end))
-                                  nil comint-last-input-end (point-max)))))
-                (if (and
-                     (<= echo-end (point-max))
-                     (= 0 (compare-buffer-substrings
-                           nil comint-last-input-start comint-last-input-end
-                           nil comint-last-input-end echo-end)))
-                    (delete-region comint-last-input-end echo-end))))
+          (when comint-process-echoes
+            (let ((echo-len (- comint-last-input-end
+                               comint-last-input-start)))
+              ;; Wait for all input to be echoed:
+              (while (and (accept-process-output proc)
+                          (> (+ comint-last-input-end echo-len)
+                             (point-max))
+                          (zerop
+                           (compare-buffer-substrings
+                            nil comint-last-input-start
+                            (- (point-max) echo-len)
+                            ;; Above difference is equivalent to
+                            ;; (+ comint-last-input-start
+                            ;;    (- (point-max) comint-last-input-end))
+                            nil comint-last-input-end (point-max)))))
+              (if (and
+                   (<= (+ comint-last-input-end echo-len)
+                       (point-max))
+                   (zerop
+                    (compare-buffer-substrings
+                     nil comint-last-input-start comint-last-input-end
+                     nil comint-last-input-end
+                     (+ comint-last-input-end echo-len))))
+                  (delete-region comint-last-input-end
+                                 (+ comint-last-input-end echo-len)))))
 
           ;; This used to call comint-output-filter-functions,
           ;; but that scrolled the buffer in undesirable ways.