Major redesign of emacs/eshell

+ :sh can now be fed commands to run immediately, e.g. :sh cd %:P to
  start from the current project root.
+ Eshell will spawn a new eshell on every split. This can be controlled
  via `+eshell-enable-new-shell-on-split'
+ Eshell can be configured to kill the window when you kill the eshell
  process. This is disabled by default. See
  `+eshell-kill-window-on-exit'. Some commands ignore this, like the
  quit-and-close command (I alias this to "q").
+ eshell-directory-name has been moved to doom-etc-dir/eshell. It will
  seem like eshell has forgotten all your history, but you can move
  ~/.eshell (or ~/.doom.d/eshell) to ~/.emacs.d/.local/etc/eshell and
  you'll be fine.
+ eshell-aliases-file has been moved to ~/.doom.d/eshell_aliases by
  default.
+ Automatic writing to eshell-aliases-file has been disabled. No shell
  so aggressively persists aliases. You may maintain it yourself, or use
  the new +eshell-aliases variable to customize eshell from Doom.
+ C-s now invokes a history search with ivy/helm.
+ C-c s and C-c v split horizontally and vertically. Inspired by tmux.
+ C-c x kill the current eshell and its window. Inspired by tmux.j
+ New set-eshell-alias! autodef for defining your own aliases.
+ +eshell/open-workspace has been replaced with +eshell/open-fullscreen.
+ Added the "cd-to-project" command. I suggest you alias it.

modules/emacs/eshell/config.el

@@ -6,11 +6,35 @@
 ;;   + `+eshell/open-workspace': open in separate tab (requires :feature
 ;;     workspaces)
 
-(defvar eshell-directory-name
-  (let ((dir (expand-file-name "eshell" doom-private-dir)))
-    (if (file-directory-p dir)
-        dir
-      "~/.eshell")))
+(defvar eshell-directory-name (concat doom-etc-dir "eshell"))
+
+(defvar eshell-aliases-file
+  (expand-file-name "eshell_aliases" doom-private-dir)
+  "The path to your eshell aliases file, where you may declare alises. This is
+here as an alternative to `set-eshell-alias!'.")
+
+;;
+(defvar +eshell-enable-new-shell-on-split t
+  "If non-nil, spawn a new eshell session after splitting from an eshell
+buffer.")
+
+(defvar +eshell-kill-window-on-exit nil
+  "If non-nil, eshell will close windows along with its eshell buffers.")
+
+(defvar +eshell-aliases
+  '(("q"  "exit")           ; built-in
+    ("z"  "cd =$1")         ; built-in
+    ("bd" "eshell-up $1")   ; `eshell-up'
+    ("rg" "rg --color=always")
+    ("ag" "ag --color=always"))
+  "An alist of default eshell aliases, meant to emulate useful shell utilities,
+like fasd and bd. Note that you may overwrite these in your
+`eshell-aliases-file'. This is here to provide an alternative, elisp-centric way
+to define your aliases.
+
+You should use `det-eshell-alias!' to change this.")
+
+(defvar +eshell--default-aliases nil)
 
 
 ;;
@@ -31,7 +55,7 @@
         eshell-hist-ignoredups t
         ;; em-prompt
         eshell-prompt-regexp "^.* λ "
-        eshell-prompt-function #'+eshell-prompt
+        eshell-prompt-function #'+eshell-default-prompt
         ;; em-glob
         eshell-glob-case-insensitive t
         eshell-error-if-no-glob t)
@@ -39,6 +63,10 @@
   ;; Consider eshell buffers real
   (add-hook 'eshell-mode-hook #'doom|mark-buffer-as-real)
 
+  ;; Keep track of open eshell buffers
+  (add-hook 'eshell-mode-hook #'+eshell|init)
+  (add-hook 'eshell-exit-hook #'+eshell|cleanup)
+
   ;; UI enhancements
   (defun +eshell|replace-fringes-with-margins ()
     "Remove eshell's fringes and give it a margin of 1."
@@ -47,28 +75,25 @@
   (add-hook 'eshell-mode-hook #'+eshell|replace-fringes-with-margins)
   (add-hook 'eshell-mode-hook #'hide-mode-line-mode)
 
-  ;; Keep track of open eshell buffers
-  (add-hook 'eshell-mode-hook #'+eshell|init)
-  (add-hook 'eshell-exit-hook #'+eshell|cleanup)
-
-  (after! em-alias
-    ;; Emulates popular shell utilities
-    (map-put eshell-command-aliases-list "z" '("cd =$1"))
-    (map-put eshell-command-aliases-list "bd" '("eshell-up $1")))
+  ;; Don't auto-write our aliases! Let us manage our own `eshell-aliases-file'
+  ;; or configure `+eshell-aliases' via elisp.
+  (advice-add #'eshell-write-aliases-list :override #'ignore)
 
+  ;; Visual commands require a proper terminal. Eshell can't handle that, so
+  ;; it delegates these commands to a term buffer.
   (after! em-term
-    ;; Visual commands require a proper terminal. Eshell can't handle that, so
-    ;; it delegates these commands to a term buffer.
     (dolist (cmd '("tmux" "htop" "bash" "zsh" "fish" "vim" "nvim" "ncmpcpp"))
-      (cl-pushnew cmd eshell-visual-commands)))
+      (add-to-list 'eshell-visual-commands cmd)))
 
-  (defun +eshell|init-evil ()
-    "Replace `evil-collection-eshell-next-prompt-on-insert' with
-`+eshell|goto-prompt-on-insert'."
-    (dolist (hook '(evil-replace-state-entry-hook evil-insert-state-entry-hook))
-      (remove-hook hook 'evil-collection-eshell-next-prompt-on-insert t)
-      (add-hook hook '+eshell|goto-prompt-on-insert nil t)))
-  (add-hook 'eshell-mode-hook #'+eshell|init-evil)
+  (defun +eshell|init-aliases ()
+    (setq +eshell--default-aliases eshell-command-aliases-list
+          eshell-command-aliases-list
+          (append eshell-command-aliases-list
+                  +eshell-aliases)))
+  (add-hook 'eshell-alias-load-hook #'+eshell|init-aliases)
+
+  (when (featurep! :feature evil +everywhere)
+    (add-hook 'eshell-mode-hook #'+eshell|init-evil))
 
   (defun +eshell|init-keymap ()
     "Setup eshell keybindings. This must be done in a hook because eshell-mode
@@ -90,6 +115,10 @@ redefines its keys every time `eshell-mode' is enabled."
         "\C-p"     #'eshell-previous-input
         "\C-n"     #'eshell-next-input))
     (define-key! eshell-mode-map
+      (kbd "C-s")   #'+eshell/search-history
+      (kbd "C-c s") #'+eshell/split-below
+      (kbd "C-c v") #'+eshell/split-right
+      (kbd "C-c x") #'+eshell/kill-and-close
       [remap split-window-below]  #'+eshell/split-below
       [remap split-window-right]  #'+eshell/split-right
       [remap doom/backward-to-bol-or-indent] #'eshell-bol