From cdf8ea7453d906740334af4d85a71cc8dd27210d Mon Sep 17 00:00:00 2001
From: Robert Bartlensky <bartlensky.robert@gmail.com>
Date: Sat, 10 Jul 2021 21:14:24 +0100
Subject: [PATCH] Error when nightly toolchain is not available.

---
 rustic-rustfmt.el | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/rustic-rustfmt.el b/rustic-rustfmt.el
index 6e9e34a5..c461fe2f 100644
--- a/rustic-rustfmt.el
+++ b/rustic-rustfmt.el
@@ -209,6 +209,8 @@ This operation requires a nightly version of rustfmt.
   (if (not (region-active-p)) (rustic-format-buffer)
     (let* ((buf (current-buffer))
            (file (buffer-file-name buf)))
+      (unless (equal (call-process "cargo" nil nil nil "+nightly") 0)
+        (error "Need nightly toolchain to format region."))
       (let ((start (+ 1 (count-lines 1 begin)))
             (len (- (count-lines begin end) 1)))
         (rustic-compilation-process-live t)