From 9775939f9d8f1fe26cc5fd807cfcfe83ef1939c2 Mon Sep 17 00:00:00 2001
From: Henrik Lissner <henrik@lissner.net>
Date: Mon, 2 Dec 2019 16:34:11 -0500
Subject: [PATCH] lang/rust: fix #2132

Prevents rust-mode from taking over *.rs files.
---
 modules/lang/rust/config.el | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/modules/lang/rust/config.el b/modules/lang/rust/config.el
index 4ef184795..dcaa14cd2 100644
--- a/modules/lang/rust/config.el
+++ b/modules/lang/rust/config.el
@@ -56,6 +56,12 @@
 (use-package! racer
   :unless (featurep! +lsp)
   :hook (rustic-mode . racer-mode)
+  :init
+  ;; Fix #2132: `racer' depends on `rust-mode', which tries to modify
+  ;; `auto-mode-alist'. We make extra sure that doesn't stick, especially when a
+  ;; buffer is reverted, as it is after rustfmt is done wiht it.
+  (after! rust-mode
+    (setq auto-mode-alist (delete '("\\.rs\\'" . rust-mode)) auto-mode-alist))
   :config
   (set-lookup-handlers! 'rustic-mode
     :definition '(racer-find-definition :async t)