doomemacs/init/init-snippets.el

(provide 'init-snippets)

(use-package yasnippet
    :mode (("emacs.+/snippets/" . snippet-mode))
    :pre-load
    (progn
      ;; Fix yasnippet keymaps so they only work in insert mode (why they
      ;; had to make this so complicated I don't know); must be defined
      ;; BEFORE we include yasnippet.
      (defvar yas-minor-mode-map
        (let ((map (make-sparse-keymap)))
          (imap map [(tab)]     'yas-expand)
          (imap map (kbd "TAB") 'yas-expand)
          map)))
    :config
    (progn
      (defadvice evil-force-normal-state (before evil-esc-quit-yasnippet activate)
        (shut-up (yas-exit-all-snippets)))

      ;; Only load personal snippets
      (setq yas-snippet-dirs `(,*snippets-dir))
      (setq yas-prompt-functions '(yas-ido-prompt yas-no-prompt))

      (after auto-complete
             (add-hook! 'yas-before-expand-snippet-hook (auto-complete-mode -1))
             (add-hook! 'yas-after-exit-snippet-hook (auto-complete-mode t))
             (defadvice ac-expand (before advice-for-ac-expand activate)
               (when (yas-expand) (ac-stop))))

      (defmap yas-keymap (kbd "DEL") 'my/yas-clear-field)

      (yas-reload-all))
    :init
    (progn
      (add-hook 'prog-mode-hook 'yas-minor-mode)
      (add-hook 'snippet-mode-hook 'yas-minor-mode)
      (add-hook 'markdown-mode-hook 'yas-minor-mode)
      (add-hook 'org-mode-hook 'yas-minor-mode)))

;; Prevents Yas from stepping on my toes when I use backspace
(defun my/yas-clear-field (&optional 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 ((and field
                (not (yas--field-modified-p field))
                (eq (point) (marker-position (yas--field-start field))))
           (yas--skip-and-clear field))
          (t (delete-char -1)))))