emacs: Special handling for version mismatch errors

[notmuch] / emacs / notmuch-lib.el

diff --git a/emacs/notmuch-lib.el b/emacs/notmuch-lib.el
index c3d76d22ab53339adf83cc8b11697023e8b46b7d..77a591d89ede485c0fbd3318511fbf71b028d338 100644 (file)
--- a/emacs/notmuch-lib.el
+++ b/emacs/notmuch-lib.el
@@ -334,6 +334,19 @@ the user dismisses it."
          (insert "\n"))))
     (pop-to-buffer buf)))
 
+(defun notmuch-check-async-exit-status (proc msg)
+  "If PROC exited abnormally, pop up an error buffer and signal an error.
+
+This is a wrapper around `notmuch-check-exit-status' for
+asynchronous process sentinels.  PROC and MSG must be the
+arguments passed to the sentinel."
+  (let ((exit-status
+        (case (process-status proc)
+          ((exit) (process-exit-status proc))
+          ((signal) msg))))
+    (when exit-status
+      (notmuch-check-exit-status exit-status (process-command proc)))))
+
 (defun notmuch-check-exit-status (exit-status command &optional output err-file)
   "If EXIT-STATUS is non-zero, pop up an error buffer and signal an error.
 
@@ -347,9 +360,18 @@ giving the output of command.  ERR-FILE, if provided, is the name
 of a file containing the error output of command.  OUTPUT and the
 contents of ERR-FILE will be included in the error message."
 
-  ;; This is implemented as a cond to make it easy to expand.
   (cond
    ((eq exit-status 0) t)
+   ((eq exit-status 20)
+    (notmuch-pop-up-error "Error: Version mismatch.
+Emacs requested an older output format than supported by the notmuch CLI.
+You may need to restart Emacs or upgrade your notmuch Emacs package.")
+    (error "notmuch CLI version mismatch"))
+   ((eq exit-status 21)
+    (notmuch-pop-up-error "Error: Version mismatch.
+Emacs requested a newer output format than supported by the notmuch CLI.
+You may need to restart Emacs or upgrade your notmuch package.")
+    (error "notmuch CLI version mismatch"))
    (t
     (notmuch-pop-up-error
      (concat
@@ -375,15 +397,23 @@ contents of ERR-FILE will be included in the error message."
   "Invoke `notmuch-command' with `args' and return the parsed JSON output.
 
 The returned output will represent objects using property lists
-and arrays as lists."
+and arrays as lists.  If notmuch exits with a non-zero status,
+this will pop up a buffer containing notmuch's output and signal
+an error."
 
   (with-temp-buffer
-    (apply #'call-process notmuch-command nil (list t nil) nil args)
-    (goto-char (point-min))
-    (let ((json-object-type 'plist)
-         (json-array-type 'list)
-         (json-false 'nil))
-      (json-read))))
+    (let ((err-file (make-temp-file "nmerr")))
+      (unwind-protect
+         (let ((status (apply #'call-process
+                              notmuch-command nil (list t err-file) nil args)))
+           (notmuch-check-exit-status status (cons notmuch-command args)
+                                      (buffer-string) err-file)
+           (goto-char (point-min))
+           (let ((json-object-type 'plist)
+                 (json-array-type 'list)
+                 (json-false 'nil))
+             (json-read)))
+       (delete-file err-file)))))
 
 ;; Compatibility functions for versions of emacs before emacs 23.
 ;;