Even more PDF-tools tweaks

Once I started tweaking pdf-tools I couldn’t resist a few more bits of streamlining my workflow. I wanted to be able to commit an annotation by hitting RET rather than C-c C-c and then use SHIFT and RET to actually enter a newline, a bit like in many messaging apps. The problem was that the necessary commands are in pdf-annot-edit-contents-minor-mode-map which is a key map that is not available until that minor mode is loaded. This causes an error if you try to define a key in that map in the same way as I did for the keys to add annotations. This is remedied by wrapping the definitions in with-eval-after-load which waits to execute the code until the file that defines the pdf-annot mode is loaded.

The other thing I wanted to do was have the pdf file auto-save every time I commit an annotation. I did this by advising the function pdf-annot-edit-contents-commit to run save-buffer afterwards. This also had to be inside with-eval-after-load as the pdf-annot-edit-contents-commit function is not available to be advised until the file defining the pdf-annot mode is loaded. The only other issue I had was that when the advice to pdf-annot-edit-contents-commit called save-buffer, it passed its argument (the text of the annotation) to save-buffer which then failed. I hacked around this by writing a simple wrapper to save buffer that ignores any arguments. There is probably a better way to do this!

Putting it all together with my previous tweaks, my pdf-tools config looks like this:

;; wrapper for save-buffer ignoring arguments
(defun bjm/save-buffer-no-args ()
  "Save buffer ignoring arguments"
  (save-buffer))

(use-package pdf-tools
 :pin manual ;;manually update
 :config
 ;; initialise
 (pdf-tools-install)
 (setq-default pdf-view-display-size 'fit-page)
 ;; automatically annotate highlights
 (setq pdf-annot-activate-created-annotations t)
 ;; use isearch instead of swiper
 (define-key pdf-view-mode-map (kbd "C-s") 'isearch-forward)
 ;; turn off cua so copy works
 (add-hook 'pdf-view-mode-hook (lambda () (cua-mode 0)))
 ;; more fine-grained zooming
 (setq pdf-view-resize-factor 1.1)
 ;; keyboard shortcuts
 (define-key pdf-view-mode-map (kbd "h") 'pdf-annot-add-highlight-markup-annotation)
 (define-key pdf-view-mode-map (kbd "t") 'pdf-annot-add-text-annotation)
 (define-key pdf-view-mode-map (kbd "D") 'pdf-annot-delete)
 ;; wait until map is available
 (with-eval-after-load "pdf-annot"
   (define-key pdf-annot-edit-contents-minor-mode-map (kbd "<return>") 'pdf-annot-edit-contents-commit)
   (define-key pdf-annot-edit-contents-minor-mode-map (kbd "<S-return>") 'newline)
   ;; save after adding comment
   (advice-add 'pdf-annot-edit-contents-commit :after 'bjm/save-buffer-no-args)))