💥 Remove :feature category

:feature was a "catch-all" category. Many of its modules fit better in
other categories, so they've been moved:

- feature/debugger -> tools/debugger
- feature/evil -> editor/evil
- feature/eval -> tools/eval
- feature/lookup -> tools/lookup
- feature/snippets -> editor/snippets
- feature/file-templates -> editor/file-templates
- feature/workspaces -> ui/workspaces

More potential changes in the future:

- A new :term category for terminal emulation modules (eshell, term and
  vterm).
- A new :os category for modules dedicated to os-specific functionality.
  The :tools macos module would fit here, but so would modules for nixos
  and arch.
- A new :services category for web-service integration, like wakatime,
  twitter, elfeed, gist and pastebin services.

modules/editor/snippets/autoload/evil.el

@@ -0,0 +1,16 @@
+;;; editor/snippets/autoload/evil.el -*- lexical-binding: t; -*-
+;;;###if (featurep! :editor evil)
+
+;;;###autoload
+(defun +snippets/expand-on-region ()
+  "Only use this with `evil-mode'. Expands a snippet around a selected region
+and switches to insert mode if there are editable fields."
+  (interactive)
+  (when (evil-visual-state-p)
+    (evil-visual-select evil-visual-beginning evil-visual-end 'inclusive))
+  (cl-letf (((symbol-function 'region-beginning) (lambda () evil-visual-beginning))
+            ((symbol-function 'region-end)       (lambda () evil-visual-end)))
+    (yas-insert-snippet))
+  (when (yas-active-snippets)
+    (evil-insert-state +1)))
+

modules/editor/snippets/autoload/settings.el

@@ -0,0 +1,10 @@
+;;; editor/snippets/autoload/settings.el -*- lexical-binding: t; -*-
+
+;;;###autodef
+(defun set-yas-minor-mode! (modes)
+  "Register minor MODES (one mode symbol or a list of them) with yasnippet so it
+can have its own snippets category, if the folder exists."
+  (dolist (mode (doom-enlist modes))
+    (let ((fn (intern (format "+snippets|register-%s" mode))))
+      (fset fn (lambda () (yas-activate-extra-mode mode)))
+      (add-hook (intern (format "%s-hook" mode)) fn))))

modules/editor/snippets/autoload/snippets.el

@@ -0,0 +1,121 @@
+;;; editor/snippets/autoload/snippets.el -*- lexical-binding: t; -*-
+
+(defun +snippets--remove-p (x y)
+  (and (equal (yas--template-key x) (yas--template-key y))
+       (file-in-directory-p (yas--template-get-file x) doom-emacs-dir)))
+
+;;;###autoload
+(defun +snippets-prompt-private (prompt choices &optional display-fn)
+  "Prioritize private snippets over built-in ones if there are multiple
+choices.
+
+There are two groups of snippets in Doom Emacs. The built in ones (under
+`doom-emacs-dir'; provided by Doom or its plugins) or your private snippets
+(outside of `doom-eamcs-dir').
+
+If there are multiple snippets with the same key in either camp (but not both),
+you will be prompted to select one.
+
+If there are conflicting keys across the two camps, the built-in ones are
+ignored. This makes it easy to override built-in snippets with private ones."
+  (when (memq this-command '(yas-expand +snippets/expand-on-region))
+    (let* ((gc-cons-threshold doom-gc-cons-upper-limit)
+           (choices (cl-remove-duplicates choices :test #'+snippets--remove-p)))
+      (if (cdr choices)
+          (cl-loop for fn in (cdr (memq '+snippets-prompt-private yas-prompt-functions))
+                   if (funcall fn prompt choices display-fn)
+                   return it)
+        (car choices)))))
+
+;;;###autoload
+(defun +snippets/goto-start-of-field ()
+  "Go to the beginning of the current field."
+  (interactive)
+  (let* ((snippet (car (yas-active-snippets)))
+         (active-field (yas--snippet-active-field snippet))
+         (position (if (yas--field-p active-field) (yas--field-start active-field) -1)))
+    (if (= (point) position)
+        (move-beginning-of-line 1)
+      (goto-char position))))
+
+;;;###autoload
+(defun +snippets/goto-end-of-field ()
+  "Go to the end of the current field."
+  (interactive)
+  (let* ((snippet (car (yas-active-snippets)))
+         (active-field (yas--snippet-active-field snippet))
+         (position (if (yas--field-p active-field) (yas--field-end active-field) -1)))
+    (if (= (point) position)
+        (move-end-of-line 1)
+      (goto-char position))))
+
+;;;###autoload
+(defun +snippets/delete-backward-char (&optional field)
+  "Prevents Yas from interfering with backspace deletion."
+  (interactive)
+  (let ((field (or field (and (overlayp yas--active-field-overlay)
+                              (overlay-buffer yas--active-field-overlay)
+                              (overlay-get yas--active-field-overlay 'yas--field)))))
+    (unless (and (yas--field-p field)
+                 (eq (point) (marker-position (yas--field-start field))))
+      (call-interactively #'delete-backward-char))))
+
+;;;###autoload
+(defun +snippets/delete-forward-char-or-field (&optional field)
+  "Delete forward, or skip the current field if it's empty. This is to prevent
+buggy behavior when <delete> is pressed in an empty field."
+  (interactive)
+  (let ((field (or field (and yas--active-field-overlay
+                              (overlay-buffer yas--active-field-overlay)
+                              (overlay-get yas--active-field-overlay 'yas--field)))))
+    (cond ((not (yas--field-p field))
+           (delete-char 1))
+          ((and (not (yas--field-modified-p field))
+                (eq (point) (marker-position (yas--field-start field))))
+           (yas--skip-and-clear field)
+           (yas-next-field 1))
+          ((eq (point) (marker-position (yas--field-end field))) nil)
+          ((delete-char 1)))))
+
+;;;###autoload
+(defun +snippets/delete-to-start-of-field (&optional field)
+  "Delete to start-of-field."
+  (interactive)
+  (unless field
+    (setq field (and (overlayp yas--active-field-overlay)
+                     (overlay-buffer yas--active-field-overlay)
+                     (overlay-get yas--active-field-overlay 'yas--field))))
+  (when (yas--field-p field)
+    (let ((sof (marker-position (yas--field-start field))))
+      (when (and field (> (point) sof))
+        (delete-region sof (point))))))
+
+
+;;
+;; Hooks
+
+;;;###autoload
+(defun +snippets|enable-project-modes (mode &rest _)
+  "Automatically enable snippet libraries for project minor modes defined with
+`def-project-mode!'."
+  (if (symbol-value mode)
+      (yas-activate-extra-mode mode)
+    (yas-deactivate-extra-mode mode)))
+
+
+;;
+;; Commands
+
+;;;###autoload
+(defun +snippets/browse (_arg)
+  "TODO"
+  (interactive "P")
+  (doom-project-browse +snippets-dir))
+
+;;;###autoload
+(defun +snippets/find-file ()
+  "TODO"
+  (interactive)
+  (if (file-directory-p +snippets-dir)
+      (doom-project-find-file +snippets-dir)
+    (yas-visit-snippet-file)))