tweak(erlang): format w/ erlfmt instead of efmt

modules/lang/erlang/README.org

@@ -40,7 +40,7 @@ This module requires Erlang be installed (which includes ~erlang-mode~). Check
 your distribution's package manager or a version management tool such as [[https://github.com/kerl/kerl][kerl]].
 
 - [[https://github.com/erlang/sourcer][sourcer]] when [[doom-module::tools lsp]] & [[doom-module:+lsp]]
-- [[https://github.com/sile/efmt][efmt]] when [[doom-module::editor format]]
+- [[https://github.com/erlang/rebar3][rebar3]] with [[https://github.com/WhatsApp/erlfmt][erlfmt]] when [[doom-module::editor format]]
 
 * TODO Usage
 #+begin_quote

modules/lang/erlang/config.el

@@ -5,7 +5,7 @@
   :mode ("/rebar\\.config\\(?:\\.script\\)?\\'" . erlang-mode)
   :mode ("/\\(?:app\\|sys\\)\\.config\\'" . erlang-mode)
   :config
-  (set-formatter! 'efmt '("efmt" "-") :modes '(erlang-mode))
+  (set-formatter! 'erlfmt '("rebar3" "fmt" "-") :modes '(erlang-mode))
   (when (modulep! +lsp)
     (add-hook 'erlang-mode-local-vars-hook #'lsp! 'append))
 

modules/lang/erlang/doctor.el

@@ -6,5 +6,5 @@
          "This module requires (:tools lsp)")
 
 (when (modulep! :editor format)
-  (unless (executable-find "efmt")
-    (warn! "Couldn't find efmt. Formatting will be disabled.")))
+  (unless (and (executable-find "rebar3") (zerop (car (doom-call-process "rebar3" "fmt" "-v"))))
+    (warn! "Couldn't find erlfmt. Formatting will be disabled.")))