From c95769af8e57c934fa138abff38d7a45a1f35cc0 Mon Sep 17 00:00:00 2001
From: Jon Pither <jon.pither@gmail.com>
Date: Fri, 26 Feb 2016 09:55:17 +0000
Subject: [PATCH] Fixes #1578 in windows process-buffer can be nil

---
 CHANGELOG.md    |  1 +
 nrepl-client.el | 50 +++++++++++++++++++++++++------------------------
 2 files changed, 27 insertions(+), 24 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 8a05a5455..e5adb6729 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -40,6 +40,7 @@ and try to associate the created connection with this project automatically.
 
 ### Bugs fixed
 
+* [#1578](https://github.com/clojure-emacs/cider/issues/1578): Nrepl-server-filter called with dead process buffer in Windows.
 * [#1441](https://github.com/clojure-emacs/cider/issues/1441): Don't popup a buffer that's already displayed.
 * [#1557](https://github.com/clojure-emacs/cider/issues/1557): When a sibling REPL is started by hasn't yet turned into a cljs REPL, it won't hijack clj requests.
 * [#1562](https://github.com/clojure-emacs/cider/issues/1562): Actually disable cider-mode when it gets disabled.
diff --git a/nrepl-client.el b/nrepl-client.el
index be812c0e1..9764a98bd 100644
--- a/nrepl-client.el
+++ b/nrepl-client.el
@@ -1111,30 +1111,32 @@ the port, and the client buffer."
 
 (defun nrepl-server-filter (process output)
   "Process nREPL server output from PROCESS contained in OUTPUT."
-  (with-current-buffer (process-buffer process)
-    ;; auto-scroll on new output
-    (let ((moving (= (point) (process-mark process))))
-      (save-excursion
-        (goto-char (process-mark process))
-        (insert output)
-        (set-marker (process-mark process) (point)))
-      (when moving
-        (goto-char (process-mark process))
-        (when-let ((win (get-buffer-window)))
-          (set-window-point win (point))))))
-  ;; detect the port the server is listening on from its output
-  (when (string-match "nREPL server started on port \\([0-9]+\\)" output)
-    (let ((port (string-to-number (match-string 1 output))))
-      (message "nREPL server started on %s" port)
-      (with-current-buffer (process-buffer process)
-        (let* ((client-proc (nrepl-start-client-process nil port process))
-               (client-buffer (process-buffer client-proc)))
-          (setq nrepl-client-buffers
-                (cons client-buffer
-                      (delete client-buffer nrepl-client-buffers)))
-
-          (when (functionp nrepl-post-client-callback)
-            (funcall nrepl-post-client-callback client-buffer)))))))
+  ;; In Windows this can be false:
+  (when (buffer-live-p (process-buffer process))
+    (with-current-buffer (process-buffer process)
+      ;; auto-scroll on new output
+      (let ((moving (= (point) (process-mark process))))
+        (save-excursion
+          (goto-char (process-mark process))
+          (insert output)
+          (set-marker (process-mark process) (point)))
+        (when moving
+          (goto-char (process-mark process))
+          (when-let ((win (get-buffer-window)))
+            (set-window-point win (point))))))
+    ;; detect the port the server is listening on from its output
+    (when (string-match "nREPL server started on port \\([0-9]+\\)" output)
+      (let ((port (string-to-number (match-string 1 output))))
+        (message "nREPL server started on %s" port)
+        (with-current-buffer (process-buffer process)
+          (let* ((client-proc (nrepl-start-client-process nil port process))
+                 (client-buffer (process-buffer client-proc)))
+            (setq nrepl-client-buffers
+                  (cons client-buffer
+                        (delete client-buffer nrepl-client-buffers)))
+
+            (when (functionp nrepl-post-client-callback)
+              (funcall nrepl-post-client-callback client-buffer))))))))
 
 (declare-function cider--close-connection-buffer "cider-client")