Corfu detected an error, with lsp-mode settings presented in doc

[drcxd]

This problem appears on Emacs 30.2, though. However, I think it is irrelevant. The error is triggered when corfu completion menu has popped up, then input space and another character. In this example, it is prefix_ e.

Corfu detected an error:
  backtrace-to-string()
  corfu--debug((void-function t))
  t("e" 1 2)
  orderless--dispatch((my/orderless-dispatch-flex-first t) (orderless-literal orderless-regexp) "e" 1 2)
  orderless--compile-component("e" 1 2 (orderless-literal orderless-regexp) (my/orderless-dispatch-flex-first t))
  orderless-compile("prefix_ e")
  orderless--compile("prefix_ e" #f(compiled-function (str pred action) #<bytecode -0x22b5564f3eb8dcc>) nil)
  orderless-all-completions("prefix_ e" #f(compiled-function (str pred action) #<bytecode -0x22b5564f3eb8dcc>) nil 9)
  #f(compiled-function (style) #<bytecode -0x1dead0d99c709757>)(orderless)
  #f(compiled-function (elt) #<bytecode -0xc1e755c61c1a985>)(orderless)
  mapc(#f(compiled-function (elt) #<bytecode -0xc1e755c61c1a985>) (orderless partial-completion basic))
  seq-do(#f(compiled-function (elt) #<bytecode -0xc1e755c61c1a985>) (orderless partial-completion basic))
  seq-some(#f(compiled-function (style) #<bytecode -0x1dead0d99c709757>) (orderless partial-completion basic))
  completion--nth-completion(2 "prefix_ e" #f(compiled-function (str pred action) #<bytecode -0x22b5564f3eb8dcc>) nil 9 (metadata (category . lsp-capf) (display-sort-function . identity) (cycle-sort-function . identity)))
  completion-all-completions("prefix_ e" #f(compiled-function (str pred action) #<bytecode -0x22b5564f3eb8dcc>) nil 9 (metadata (category . lsp-capf) (display-sort-function . identity) (cycle-sort-function . identity)))
  apply(completion-all-completions ("prefix_ e" #f(compiled-function (str pred action) #<bytecode -0x22b5564f3eb8dcc>) nil 9 (metadata (category . lsp-capf) (display-sort-function . identity) (cycle-sort-function . identity))))
  corfu--filter-completions("prefix_ e" #f(compiled-function (str pred action) #<bytecode -0x22b5564f3eb8dcc>) nil 9 (metadata (category . lsp-capf) (display-sort-function . identity) (cycle-sort-function . identity)))
  corfu--recompute("prefix_ e" 9 #f(compiled-function (str pred action) #<bytecode -0x22b5564f3eb8dcc>) nil)
  corfu--update(interruptible)
  #f(compiled-function (&optional auto) #<bytecode 0x131ac3147ca3b29a>)()
  apply(#f(compiled-function (&optional auto) #<bytecode 0x131ac3147ca3b29a>) nil)
  #f(compiled-function (&rest args) #<bytecode 0x1a6cfa11f4d9d8eb>)()
  apply(#f(compiled-function (&rest args) #<bytecode 0x1a6cfa11f4d9d8eb>) nil)
  corfu--exhibit()
  #f(compiled-function () #<bytecode 0x1c4a549ee1debdc1>)()
  #f(compiled-function () #<bytecode 0x197b69a44d616672>)()
  handler-bind-1(#f(compiled-function () #<bytecode 0x197b69a44d616672>) (error) corfu--debug)
  corfu--protect(#f(compiled-function () #<bytecode 0x1c4a549ee1debdc1>))
  corfu--post-command()

I am using the lsp-mode configs in documents: https://github.com/minad/corfu/wiki#advanced-example-configuration-with-orderless

My minimal config file to reproduce:

(defvar elpaca-installer-version 0.11)
(defvar elpaca-directory (expand-file-name "elpaca/" user-emacs-directory))
(defvar elpaca-builds-directory (expand-file-name "builds/" elpaca-directory))
(defvar elpaca-repos-directory (expand-file-name "repos/" elpaca-directory))
(defvar elpaca-order '(elpaca :repo "https://github.com/progfolio/elpaca.git"
                              :ref nil :depth 1 :inherit ignore
                              :files (:defaults "elpaca-test.el" (:exclude "extensions"))
                              :build (:not elpaca--activate-package)))
(let* ((repo  (expand-file-name "elpaca/" elpaca-repos-directory))
       (build (expand-file-name "elpaca/" elpaca-builds-directory))
       (order (cdr elpaca-order))
       (default-directory repo))
  (add-to-list 'load-path (if (file-exists-p build) build repo))
  (unless (file-exists-p repo)
    (make-directory repo t)
    (when (<= emacs-major-version 28) (require 'subr-x))
    (condition-case-unless-debug err
        (if-let* ((buffer (pop-to-buffer-same-window "*elpaca-bootstrap*"))
                  ((zerop (apply #'call-process `("git" nil ,buffer t "clone"
                                                  ,@(when-let* ((depth (plist-get order :depth)))
                                                      (list (format "--depth=%d" depth) "--no-single-branch"))
                                                  ,(plist-get order :repo) ,repo))))
                  ((zerop (call-process "git" nil buffer t "checkout"
                                        (or (plist-get order :ref) "--"))))
                  (emacs (concat invocation-directory invocation-name))
                  ((zerop (call-process emacs nil buffer nil "-Q" "-L" "." "--batch"
                                        "--eval" "(byte-recompile-directory \".\" 0 'force)")))
                  ((require 'elpaca))
                  ((elpaca-generate-autoloads "elpaca" repo)))
            (progn (message "%s" (buffer-string)) (kill-buffer buffer))
          (error "%s" (with-current-buffer buffer (buffer-string))))
      ((error) (warn "%s" err) (delete-directory repo 'recursive))))
  (unless (require 'elpaca-autoloads nil t)
    (require 'elpaca)
    (elpaca-generate-autoloads "elpaca" repo)
    (load "./elpaca-autoloads")))
(add-hook 'after-init-hook #'elpaca-process-queues)
(elpaca `(,@elpaca-order))

;; Uncomment for systems which cannot create symlinks:
(if (eq system-type 'windows-nt)
    (elpaca-no-symlink-mode))

(elpaca elpaca-use-package
  ;; Enable Elpaca's use-package support
  (elpaca-use-package-mode))
;; Block until package is installed/activated so we can use it at the top-level below.
(elpaca-wait)

;; lsp-mode


(use-package lsp-mode
  :ensure t
  :defer t
  :init
  (defun my/orderless-dispatch-flex-first (_pattern index _total)
    (and (eq index 0) 'orderless-flex))
  (defun corfu-lsp-setup ()
    (setf (alist-get 'styles (alist-get 'lsp-capf completion-category-defaults))
          '(orderless))
    ;; Optionally configure the first word as flex filtered.
    (add-hook 'orderless-style-dispatchers #'my/orderless-dispatch-flex-first nil 'local)
    ;; Optionally configure the cape-capf-buster.
    (setq-local completion-at-point-functions (list (cape-capf-buster #'lsp-completion-at-point)))
    (advice-add #'lsp-completion-at-point :around #'cape-wrap-noninterruptible))
  (with-eval-after-load 'corfu
    (with-eval-after-load 'cape
      (setq lsp-completion-provider :none)
      (add-hook 'lsp-completion-mode-hook #'corfu-lsp-setup)))
  :config
  (setq lsp-headerline-breadcrumb-enable nil
        lsp-semantic-tokens-apply-modifiers nil
        lsp-semantic-tokens-enable t
        lsp-enable-on-type-formatting nil
        read-process-output-max (* 1024 1024)) ;; to increase lsp performance
)

;; orderless

(use-package orderless
  :ensure t
  :demand t
  :config
  (setq completion-styles '(orderless partial-completion basic)
        completion-category-defaults nil
        ;; completion-category-overrides '((file (styles partial-completion)))))
        completion-category-overrides nil))

;; corfu


(use-package corfu
  :ensure t
  :init
  (setq corfu-auto nil
        corfu-cycle t
        corfu-quit-at-boundary nil
        corfu-quit-no-match nil
        corfu-preview-current nil
        ;; disalbe corfu in gud-mode, see
        ;; https://github.com/minad/corfu/issues/157 for more detail
        corfu-excluded-modes '(gud-mode))
  (defun corfu-enable-in-minibuffer ()
    "Enable Corfu in the minibuffer if `completion-at-point' is bound."
    (when (where-is-internal #'completion-at-point (list (current-local-map)))
      (corfu-mode 1)))
  (global-corfu-mode)
  (corfu-popupinfo-mode)
  :hook
  (minibuffer-setup . corfu-enable-in-minibuffer)
  :bind
  (:map corfu-map
        ("C-n" . corfu-next)
        ("C-p" . corfu-previous)
        ("<tab>" . corfu-next)
        ("S-<tab>" . corfu-previous)
        ("C-g" . corfu-quit)
        ("<escape>" . corfu-quit)
        ("SPC" . corfu-insert-separator)))

(unless (display-graphic-p)
  (progn
    (use-package corfu-terminal :defer t)
    (corfu-terminal-mode +1)))

;; cape

;; (use-package company :defer t :ensure t)
(use-package cape
  :ensure t
  :demand t
  :config
  (add-to-list 'completion-at-point-functions #'cape-abbrev)
  (add-to-list 'completion-at-point-functions #'cape-dabbrev)
  (add-to-list 'completion-at-point-functions #'cape-file)
  ;; (add-to-list 'completion-at-point-functions #'cape-elisp-block)
  ;; (add-to-list 'completion-at-point-functions #'cape-elisp-symbol)
  ;; (add-to-list 'completion-at-point-functions #'cape-history)
  ;; (add-to-list 'completion-at-point-functions #'cape-keyword)
  ;; (add-to-list 'completion-at-point-functions (cape-company-to-capf #'company-clang))
  )

[minad]

This is caused by a misconfiguration:

(add-hook 'orderless-style-dispatchers #'my/orderless-dispatch-flex-first nil 'local)

orderless-style-dispatchers and orderless-matching-styles are lists of functions but not hooks! The defcustom has :type (repeat function). In contrast, hook variables can have the non-function value t as part of the list.

[minad]

See oantolin/orderless@9cf1c90