Turn off super-save in rust-mode

Related to #1372, it appears that `super-save` doesn't play nicely
with LSP features in `rust-mode`.

CHANGELOG.md

@@ -34,6 +34,7 @@
 * Fix fall back to sample `prelude-modules.el` not working if user has installed to non-default location.
 * Stop requiring `helm-config` since upstream has removed the module.
 * Require `typescript-mode` using `prelude-require-packages` to avoid error upon inclusion in `personal/prelude-modules.el`.
+* Turn off `super-save` in `rust-mode` to prevent severe hangs during autocomplete.
 
 ## 1.1.0 (2021-02-14)
 

modules/prelude-rust.el

@@ -48,6 +48,9 @@
 (require 'tree-sitter)
 (require 'tree-sitter-langs)
 
+(add-to-list 'super-save-predicates
+             (lambda () (not (eq major-mode 'rust-mode))))
+
 (with-eval-after-load 'rust-mode
   (add-hook 'rust-mode-hook 'cargo-minor-mode)
   (add-hook 'flycheck-mode-hook 'flycheck-rust-setup)