Auctex hook causes an error when set with use-package :hook versus add-hook?

Question

According to the use-package documentation these two are the same:

(use-package ace-jump-mode
  :hook (prog-mode . ace-jump-mode))

(use-package ace-jump-mode
  :commands ace-jump-mode
  :init
  (add-hook 'prog-mode-hook #'ace-jump-mode))

I have the following in my configs:

(use-package auctex
  :ensure t 
  :after latex
  :init
  [snip]
  (add-hook
   'TeX-after-compilation-finished-functions
   #'TeX-revert-document-buffer)
  :hook
  ;; (TeX-after-compilation-finished-functions . TeX-revert-document-buffer) ; Causes errors?
  [snip]

If I take out the add-hook way and uncomments the :hook way then I get the following errors each time I compile a latex document followed by a subsequent pdf buffer revert:

error in process sentinel: image-display-size: Invalid image specification: nil
error in process sentinel: Invalid image specification: nil

Note that when I define the hooks using add-hook, that does not produce the errors.

Could someone tell what's going on?

Answer 1

You can find out what is going on yourself by putting the cursor after the use-package stanza and doing M-x pp-macroexpand-last-sexp. You will discover that the :hook line expands to

(add-hook 'TeX-after-compilation-finished-functions-hook #'TeX-revert-document-buffer)

which is not what you wanted.

Long story short: :hook only does what you want if the car of the alist names a hook in a rather simple-minded way. In your case, calling add-hook explicitly is the way to go.