In Python with flake8 we can do that with #noqa in the end of line. How the same can be done with Emacs Lisp?
My ambition is to disable a particular lint error by just make a annotation with a comment like is provided in the above picture. This is possible in Emacs Lisp or there is a better way for it?
Avoiding a specific flycheck decoration is not built-in but can easily be added.
The flycheck overlays are generated by flycheck-add-overlay which is luckily only called via the hook flycheck-process-error-functions.
Functions in that hook are run with a single arg -- the error -- until one of them succeeds.
The strategy is to add a function in flycheck-process-error-functions in front of flycheck-add-overlay that returns t when the error should be ignored.
That function can be added locally for buffers in emacs-lisp-mode.
In the following example flycheck errors are ignored in emacs-lisp-mode if the line with the error ends in ;noflycheck. You can add the code to your init file.
(defcustom flycheck-elisp-noflycheck-marker ";noflycheck"
"Flycheck line regions marked with this marker string are ignored."
:type 'string
:group 'flycheck)
(defun flycheck-elisp-noflycheck (err)
"Ignore flycheck if line of ERR ends with `flycheck-elisp-noflycheck-marker'."
(save-excursion
(goto-char (cdr (flycheck-error-line-region err)))
(looking-back flycheck-elisp-noflycheck-marker
(max (- (point) (length flycheck-elisp-noflycheck-marker))
(point-min)))))
(defun elisp-noflycheck-hook ()
"Add the ;;;###noflycheck thing to elisp."
(require 'flycheck)
(add-hook 'flycheck-process-error-functions #'flycheck-elisp-noflycheck nil t))
(add-hook 'emacs-lisp-mode-hook #'elisp-noflycheck-hook)
The application in your usage example would be like follows.
(require 'prelude-packages) ;noflycheck
In February 2020, the calculation method of the error region is refactored. The function flycheck-error-line-regionis no longer available.
(goto-char (cdr (flycheck-error-line-region err)))
Tobias's answer needs an update.
(goto-char (cdr (flycheck--exact-region err)))
(goto-char (cdr (flycheck-error-region-for-mode err 'symbols))), actually.
Commented
Jun 17, 2021 at 13:35
Pythonandflake8here but describe what you want to know.flycheckusesbyte-compilein a separate asynchronous Emacs process. So the listbyte-compile-warningsis relevant for the issued warnings. Emacs is called with-Qand--batchso your initialization is ignored in the checker. But you can inject your code with options such asflycheck-emacs-lisp-package-initialize-form. Seeflycheck-define-checker emacs-lispinflycheck.el.flake8does and what you expect. Better describe exactly what you expect. (E.g.: It could work like follows: If I add a commentnoqaas in the following picture then the warning about the non-existingprelude-packagesshould be suppressed.)(require 'prelude-packages nil t)instead of(require 'prelude-packages)? You can even use something like(unless (require 'prelude-packages nil t) (user-error "Library prelude-packages not found")).