ELP language server seems to ignore .elp_lints.toml (when in IDE)

[JonathanArns]

This is basically a duplicate of #87, but I am opening a new issue, since the original was closed even though the underlying issue is not solved.

I would like some way of selectively enabling/disabling lints project-wide and for all developers working on the project, so I think the workaround of using LSP configuration that was presented in the linked thread does not cut it.

I understand from the thread that some major changes to the configuration mechanism might be needed. @robertoaloi @alanz is this on the roadmap?

[robertoaloi]

@JonathanArns Yes, we expect a lot of config-related changes in Q3 2025, most likely after summer.

[cfclavijo]

I'm using this for Emacs with Eglot

(defvar my/elp-ignored-diagnostic-codes
  '("W0038" "W0051")
  "List of diagnostic codes to ignore in erlang-mode when elp.")

(defun my/eglot-filter-diagnostics (diagnostics)
  "Filter out DIAGNOSTICS with codes in `my/elp-ignored-diagnostic-codes`."
  (when diagnostics
    (seq-remove
     (lambda (fcode)
       (let ((dcode (plist-get
                     (cdr (assoc 'eglot-lsp-diag (flymake-diagnostic-data fcode)))
                     :code)))
         (member dcode my/elp-ignored-diagnostic-codes)))
     diagnostics)))

(defun my/eglot-handle-diagnostics-advice (diagnostics)
  "Filter DIAGNOSTICS before eglot sends them to flymake."
  (let ((filtered (my/eglot-filter-diagnostics (car diagnostics))))
      (setf diagnostics (list filtered))
    diagnostics))

(with-eval-after-load 'eglot
  (advice-add 'eglot--report-to-flymake
              :filter-args #'my/eglot-handle-diagnostics-advice))