tweak(default): better vanilla multiple-cursor bindings

modules/config/default/+emacs-bindings.el

@@ -439,10 +439,10 @@
       (:when (modulep! :editor multiple-cursors)
        (:prefix-map ("m" . "multiple-cursors")
         :desc "Edit lines"         "l"         #'mc/edit-lines
-        :desc "Mark next"          "n"         #'mc/mark-next-like-this
-        :desc "Unmark next"        "N"         #'mc/unmark-next-like-this
-        :desc "Mark previous"      "p"         #'mc/mark-previous-like-this
-        :desc "Unmark previous"    "P"         #'mc/unmark-previous-like-this
+        :desc "Mark next"          "n"         #'+mc/transient-mark-next-like-this
+        :desc "Unmark next"        "N"         #'+mc/transient-unmark-next-like-this
+        :desc "Mark previous"      "p"         #'+mc/transient-mark-previous-like-this
+        :desc "Unmark previous"    "P"         #'+mc/transient-unmark-previous-like-this
         :desc "Mark all"           "t"         #'mc/mark-all-like-this
         :desc "Mark all DWIM"      "m"         #'mc/mark-all-like-this-dwim
         :desc "Edit line endings"  "e"         #'mc/edit-ends-of-lines
@@ -543,7 +543,11 @@
         "C-c h" #'+ein/hydra/body)
 
       ;;; expand-region
-      "C-="  #'er/expand-region
+      "C-="  (cmd! (call-interactively #'er/expand-region)
+                   (set-transient-map +er-transient-map t))
+
+      ;; multiple-cursors
+      "C-+"  #'mc/mark-next-like-this
 
       ;;; flycheck
       (:after flycheck

modules/config/default/+emacs.el

@@ -10,8 +10,21 @@
 (delete-selection-mode +1)
 
 (use-package! expand-region
-  :commands (er/contract-region er/mark-symbol er/mark-word)
+  :commands (er/expand-region er/contract-region er/mark-symbol er/mark-word)
+  :init
+  (setq expand-region-fast-keys-enabled nil)
   :config
+  ;; Configure the transient map called when expanding a region
+  (setq +er-transient-map
+        (let ((t-map (make-sparse-keymap)))
+          (define-key t-map (kbd "C-=") #'er/expand-region)
+          (define-key t-map (kbd "=") #'er/expand-region)
+          (define-key t-map (kbd "C--") #'er/contract-region)
+          (define-key t-map (kbd "-") #'er/contract-region)
+          (define-key t-map (kbd "C-0") (cmd! (er/expand-region 0)))
+          (define-key t-map (kbd "0") (cmd! (er/expand-region 0)))
+          t-map))
+  ;; Custom expansion quitting
   (defadvice! doom--quit-expand-region-a (&rest _)
     "Properly abort an expand-region region."
     :before '(evil-escape doom/escape)

modules/editor/multiple-cursors/autoload/vanilla-mc.el

@@ -0,0 +1,28 @@
+;;; editor/multiple-cursors/autoload/vanilla-mc.el -*- lexical-binding: t; -*-
+;;;###if (not (modulep! :editor evil))
+
+;;;###autoload
+(defun +mc/transient-call (func)
+  (require 'multiple-cursors)
+  (set-transient-map +mc-transient-map t)
+  (call-interactively func))
+
+;;;###autoload
+(defun +mc/transient-mark-next-like-this ()
+  (interactive)
+  (+mc/transient-call #'mc/mark-next-like-this))
+
+;;;###autoload
+(defun +mc/transient-unmark-next-like-this ()
+  (interactive)
+  (+mc/transient-call #'mc/unmark-next-like-this))
+
+;;;###autoload
+(defun +mc/transient-mark-previous-like-this ()
+  (interactive)
+  (+mc/transient-call #'mc/mark-previous-like-this))
+
+;;;###autoload
+(defun +mc/transient-unmark-previous-like-this ()
+  (interactive)
+  (+mc/transient-call #'mc/unmark-previous-like-this))

modules/editor/multiple-cursors/config.el

@@ -166,7 +166,25 @@
   ;; Can't use `mc/cmds-to-run-once' because mc-lists.el overwrites it
   (add-to-list 'mc--default-cmds-to-run-once 'swiper-mc)
 
-  ;; TODO multiple-cursors config for Emacs users?
+  ;; Use transient commands with vanilla Emacs.
+  (when (not (modulep! :editor evil))
+    ;; Transient map used to better control multiple-cursors in vanilla Emacs.
+    ;; This map is disabled if a key not in the map is pressed (e.g., "q").
+    (setq +mc-transient-map
+          (let ((t-map (make-sparse-keymap)))
+            (define-key t-map (kbd "n") #'mc/mark-next-like-this)
+            (define-key t-map (kbd "N") #'mc/unmark-next-like-this)
+            (define-key t-map (kbd "p") #'mc/mark-previous-like-this)
+            (define-key t-map (kbd "P") #'mc/unmark-previous-like-this)
+            t-map))
+    ;; All functions called from the transient map need to be named (i.e., not
+    ;; be lambdas). These functions need to be further added to the "run once"
+    ;; category to avoid duplicating calls.
+    (mapc (lambda (func) (add-to-list 'mc--default-cmds-to-run-once func))
+          '(+mc/transient-mark-next-like-this
+            +mc/transient-mark-previous-like-this
+            +mc/transient-unmark-next-like-this
+            +mc/transient-unmark-previous-like-this)))
 
   ;; mc doesn't play well with evil, this attempts to assuage some of its
   ;; problems so that any plugins that depend on multiple-cursors (which I have