From 1d266e6960e4b2f9ebbf175249ecf4932bc65cae Mon Sep 17 00:00:00 2001
From: Andreas Gerler <baron@bundesbrandschatzamt.de>
Date: Sun, 22 Dec 2024 12:58:58 +0100
Subject: [PATCH] update flycheck

Signed-off-by: Andreas Gerler <baron@bundesbrandschatzamt.de>
---
 elpa/flycheck-20230813.620/flycheck-pkg.el    |   18 -
 .../flycheck-autoloads.el                     |   22 +-
 .../flycheck-buttercup.el                     |    0
 .../flycheck-ert.el                           |   73 +-
 elpa/flycheck-20241130.1502/flycheck-pkg.el   |   12 +
 .../flycheck.el                               | 1213 +++++++++++------
 elpa/flycheck-readme.txt                      |   30 -
 7 files changed, 834 insertions(+), 534 deletions(-)
 delete mode 100644 elpa/flycheck-20230813.620/flycheck-pkg.el
 rename elpa/{flycheck-20230813.620 => flycheck-20241130.1502}/flycheck-autoloads.el (91%)
 rename elpa/{flycheck-20230813.620 => flycheck-20241130.1502}/flycheck-buttercup.el (100%)
 rename elpa/{flycheck-20230813.620 => flycheck-20241130.1502}/flycheck-ert.el (86%)
 create mode 100644 elpa/flycheck-20241130.1502/flycheck-pkg.el
 rename elpa/{flycheck-20230813.620 => flycheck-20241130.1502}/flycheck.el (93%)
 delete mode 100644 elpa/flycheck-readme.txt

diff --git a/elpa/flycheck-20230813.620/flycheck-pkg.el b/elpa/flycheck-20230813.620/flycheck-pkg.el
deleted file mode 100644
index df233a64..00000000
--- a/elpa/flycheck-20230813.620/flycheck-pkg.el
+++ /dev/null
@@ -1,18 +0,0 @@
-(define-package "flycheck" "20230813.620" "On-the-fly syntax checking"
-  '((emacs "25.1")
-    (dash "2.12.1")
-    (pkg-info "0.4")
-    (let-alist "1.0.4")
-    (seq "1.11"))
-  :commit "773c3eb31ebeb6bb2f9f57d28177882ca7073df0" :authors
-  '(("Sebastian Wiesner" . "swiesner@lunaryorn.com"))
-  :maintainers
-  '(("Clément Pit-Claudel" . "clement.pitclaudel@live.com"))
-  :maintainer
-  '("Clément Pit-Claudel" . "clement.pitclaudel@live.com")
-  :keywords
-  '("convenience" "languages" "tools")
-  :url "http://www.flycheck.org")
-;; Local Variables:
-;; no-byte-compile: t
-;; End:
diff --git a/elpa/flycheck-20230813.620/flycheck-autoloads.el b/elpa/flycheck-20241130.1502/flycheck-autoloads.el
similarity index 91%
rename from elpa/flycheck-20230813.620/flycheck-autoloads.el
rename to elpa/flycheck-20241130.1502/flycheck-autoloads.el
index 95975238..c29ab306 100644
--- a/elpa/flycheck-20230813.620/flycheck-autoloads.el
+++ b/elpa/flycheck-20241130.1502/flycheck-autoloads.el
@@ -13,6 +13,8 @@
 
 (autoload 'flycheck-manual "flycheck" "\
 Open the Flycheck manual." t)
+(autoload 'flycheck-quick-help "flycheck" "\
+Display brief Flycheck help." t)
 (autoload 'flycheck-mode "flycheck" "\
 Flycheck is a minor mode for on-the-fly syntax checking.
 
@@ -33,10 +35,11 @@ Flycheck displays its status in the mode line.  In the default
 configuration, it looks like this:
 
 `FlyC'     This buffer has not been checked yet.
-`FlyC-'    Flycheck doesn't have a checker for this buffer.
 `FlyC*'    Flycheck is running.  Expect results soon!
-`FlyC:3|2' This buffer contains three warnings and two errors.
+`FlyC:0'   Last check resulted in no errors and no warnings.
+`FlyC:3|5' This buffer contains three errors and five warnings.
            Use `\\[flycheck-list-errors]' to see the list.
+`FlyC-'    Flycheck doesn't have a checker for this buffer.
 
 You may also see the following icons:
 `FlyC!'    The checker crashed.
@@ -209,6 +212,21 @@ of command checkers is `flycheck-sanitize-errors'.
      If this property is given and has a non-nil value, send the
      contents of the buffer on standard input.
 
+     Some checkers that support reading from standard input have
+     a separate flag to indicate the name of the file whose
+     contents are being passed on standard input (typically
+     `stdin-filename').  In that case, use the `(option)' form in
+     `:command' to pass the value of variable `buffer-file-name'
+     when the current buffer has a file name (that is,
+     use `option \"--stdin-file-name\" buffer-file-name').
+
+     For buffers not backed by files, checkers that support input
+     on stdin typically report a file name like `-' or `<stdin>'.
+     Make sure your error parser or patterns expect these file
+     names (for example, use `(or \"<stdin>\" (file-name))') or
+     call `flycheck-remove-error-file-names' in a custom
+     `:error-filter'.
+
      Defaults to nil.
 
 Note that you may not give `:start', `:interrupt', and
diff --git a/elpa/flycheck-20230813.620/flycheck-buttercup.el b/elpa/flycheck-20241130.1502/flycheck-buttercup.el
similarity index 100%
rename from elpa/flycheck-20230813.620/flycheck-buttercup.el
rename to elpa/flycheck-20241130.1502/flycheck-buttercup.el
diff --git a/elpa/flycheck-20230813.620/flycheck-ert.el b/elpa/flycheck-20241130.1502/flycheck-ert.el
similarity index 86%
rename from elpa/flycheck-20230813.620/flycheck-ert.el
rename to elpa/flycheck-20241130.1502/flycheck-ert.el
index 1cd94f44..f8219e91 100644
--- a/elpa/flycheck-20230813.620/flycheck-ert.el
+++ b/elpa/flycheck-20241130.1502/flycheck-ert.el
@@ -37,54 +37,6 @@
 (require 'ert)
 (require 'macroexp)                     ; For macro utilities
 
-
-;;; Compatibility
-
-(eval-and-compile
-  ;; Provide `ert-skip' and friends for Emacs 24.3
-  (defconst flycheck-ert-ert-can-skip (fboundp 'ert-skip)
-    "Whether ERT supports test skipping.")
-
-  (unless (fboundp 'define-error)
-    ;; from Emacs `subr.el'
-    (defun define-error (name message &optional parent)
-      "Define NAME as a new error signal.
-MESSAGE is a string that will be output to the echo area if such an error
-is signaled without being caught by a `condition-case'.
-PARENT is either a signal or a list of signals from which it inherits.
-Defaults to `error'."
-      (unless parent (setq parent 'error))
-      (let ((conditions
-             (if (consp parent)
-                 (apply #'append
-                        (mapcar
-                         (lambda (parent)
-                           (cons parent
-                                 (or (get parent 'error-conditions)
-                                     (error "Unknown signal `%s'" parent))))
-                         parent))
-               (cons parent (get parent 'error-conditions)))))
-        (put name 'error-conditions
-             (delete-dups (copy-sequence (cons name conditions))))
-        (when message (put name 'error-message message)))))
-
-  (unless flycheck-ert-ert-can-skip
-    ;; Fake skipping
-
-    (define-error 'flycheck-ert-skipped "Test skipped")
-
-    (defun ert-skip (data)
-      (signal 'flycheck-ert-skipped data))
-
-    (defmacro skip-unless (form)
-      `(unless (ignore-errors ,form)
-         (signal 'flycheck-ert-skipped ',form)))
-
-    (defun ert-test-skipped-p (result)
-      (and (ert-test-failed-p result)
-           (eq (car (ert-test-failed-condition result))
-               'flycheck-ert-skipped)))))
-
 
 ;;; Internal variables
 
@@ -200,16 +152,7 @@ should use to lookup resource files."
       (error "No tests defined.  \
 Call `flycheck-ert-initialize' after defining all tests!"))
 
-    (setq flycheck-ert--resource-directory resource-dir)
-
-    ;; Emacs 24.3 don't support skipped tests, so we add poor man's test
-    ;; skipping: We mark skipped tests as expected failures by adjusting the
-    ;; expected result of all test cases. Not particularly pretty, but works :)
-    (unless flycheck-ert-ert-can-skip
-      (dolist (test tests)
-        (let ((result (ert-test-expected-result-type test)))
-          (setf (ert-test-expected-result-type test)
-                `(or ,result (satisfies ert-test-skipped-p))))))))
+    (setq flycheck-ert--resource-directory resource-dir)))
 
 
 ;;; Test case definitions
@@ -327,8 +270,8 @@ failed, and the test aborted with failure.")
 Raise an assertion error if the buffer is not clear afterwards."
   (flycheck-clear)
   (should (not flycheck-current-errors))
-  (should (not (-any? (lambda (ov) (overlay-get ov 'flycheck-overlay))
-                      (overlays-in (point-min) (point-max))))))
+  (should (not (seq-find (lambda (ov) (overlay-get ov 'flycheck-overlay))
+                         (overlays-in (point-min) (point-max))))))
 
 
 ;;; Test assertions
@@ -343,11 +286,11 @@ Raise an assertion error if the buffer is not clear afterwards."
   "Test that ERROR has a proper overlay in the current buffer.
 
 ERROR is a Flycheck error object."
-  (let* ((overlay (-first (lambda (ov)
-                            (equal (flycheck-error-without-group
-                                    (overlay-get ov 'flycheck-error))
-                                   (flycheck-error-without-group error)))
-                          (flycheck-overlays-in 0 (+ 1 (buffer-size)))))
+  (let* ((overlay (seq-find (lambda (ov)
+                              (equal (flycheck-error-without-group
+                                      (overlay-get ov 'flycheck-error))
+                                     (flycheck-error-without-group error)))
+                            (flycheck-overlays-in 0 (+ 1 (buffer-size)))))
          (region
           ;; Overlays of errors from other files are on the first line
           (if (flycheck-relevant-error-other-file-p error)
diff --git a/elpa/flycheck-20241130.1502/flycheck-pkg.el b/elpa/flycheck-20241130.1502/flycheck-pkg.el
new file mode 100644
index 00000000..3fd2f435
--- /dev/null
+++ b/elpa/flycheck-20241130.1502/flycheck-pkg.el
@@ -0,0 +1,12 @@
+;; -*- no-byte-compile: t; lexical-binding: nil -*-
+(define-package "flycheck" "20241130.1502"
+  "On-the-fly syntax checking."
+  '((emacs "26.1"))
+  :url "https://github.com/flycheck/flycheck"
+  :commit "ebaf48359b3e21879c8f6f3c1b5d0221b345035e"
+  :revdesc "ebaf48359b3e"
+  :keywords '("convenience" "languages" "tools")
+  :authors '(("Sebastian Wiesner" . "swiesner@lunaryorn.com"))
+  :maintainers '(("Clément Pit-Claudel" . "clement.pitclaudel@live.com")
+                 ("fmdkdd" . "fmdkdd@gmail.com")
+                 ("Bozhidar Batsov" . "bozhidar@batsov.dev")))
diff --git a/elpa/flycheck-20230813.620/flycheck.el b/elpa/flycheck-20241130.1502/flycheck.el
similarity index 93%
rename from elpa/flycheck-20230813.620/flycheck.el
rename to elpa/flycheck-20241130.1502/flycheck.el
index 91b5e16d..0aee4ede 100644
--- a/elpa/flycheck-20230813.620/flycheck.el
+++ b/elpa/flycheck-20241130.1502/flycheck.el
@@ -1,16 +1,18 @@
 ;;; flycheck.el --- On-the-fly syntax checking -*- lexical-binding: t; -*-
 
-;; Copyright (C) 2017-2022 Flycheck contributors
+;; Copyright (C) 2017-2024 Flycheck contributors
 ;; Copyright (C) 2012-2016 Sebastian Wiesner and Flycheck contributors
 ;; Copyright (C) 2013, 2014 Free Software Foundation, Inc.
 ;;
 ;; Author: Sebastian Wiesner <swiesner@lunaryorn.com>
 ;; Maintainer: Clément Pit-Claudel <clement.pitclaudel@live.com>
 ;;             fmdkdd <fmdkdd@gmail.com>
-;; URL: http://www.flycheck.org
+;;             Bozhidar Batsov <bozhidar@batsov.dev>
+;; URL: https://www.flycheck.org
 ;; Keywords: convenience, languages, tools
-;; Version: 33-cvs
-;; Package-Requires: ((emacs "25.1") (dash "2.12.1") (pkg-info "0.4") (let-alist "1.0.4") (seq "1.11"))
+;; Package-Version: 20241130.1502
+;; Package-Revision: ebaf48359b3e
+;; Package-Requires: ((emacs "26.1"))
 
 ;; This file is not part of GNU Emacs.
 
@@ -25,11 +27,11 @@
 ;; GNU General Public License for more details.
 
 ;; You should have received a copy of the GNU General Public License
-;; along with this program.  If not, see <http://www.gnu.org/licenses/>.
+;; along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
 ;;; Commentary:
 
-;; On-the-fly syntax checking for GNU Emacs 24.
+;; On-the-fly syntax checking for GNU Emacs.
 ;;
 ;; Flycheck is a modern on-the-fly syntax checking extension for GNU Emacs,
 ;; intended as replacement for the older Flymake extension which is part of GNU
@@ -42,7 +44,7 @@
 ;; It comes with a rich interface for custom syntax checkers and other
 ;; extensions, and has already many 3rd party extensions adding new features.
 ;;
-;; Please read the online manual at http://www.flycheck.org for more
+;; Please read the online manual at https://www.flycheck.org for more
 ;; information.  You can open the manual directly from Emacs with `M-x
 ;; flycheck-manual'.
 ;;
@@ -69,17 +71,15 @@
   (require 'pcase)          ; `pcase-dolist' (`pcase' itself is autoloaded)
   )
 
-(require 'dash)
-
 (require 'seq)                   ; Sequence functions
-(require 'subr-x nil 'no-error)  ; Additional utilities, Emacs 24.4 and upwards
+(require 'subr-x)                ; Additional utilities
 (require 'cl-lib)                ; `cl-defstruct' and CL utilities
 (require 'tabulated-list)        ; To list errors
 (require 'easymenu)              ; Flycheck Mode menu definition
 (require 'rx)                    ; Regexp fanciness in `flycheck-define-checker'
 (require 'help-mode)             ; `define-button-type'
 (require 'find-func)             ; `find-function-regexp-alist'
-(require 'json)                  ; `flycheck-parse-tslint'
+(require 'json)                  ; `flycheck-parse-json'
 (require 'ansi-color)            ; `flycheck-parse-with-patterns-without-color'
 
 
@@ -93,57 +93,13 @@
 ;; Tell the byte compiler about autoloaded functions from packages
 (declare-function pkg-info-version-info "pkg-info" (package))
 
-
-;;; Compatibility
-(eval-and-compile
-  (unless (fboundp 'string-suffix-p)
-    ;; TODO: Remove when dropping support for Emacs 24.3 and earlier
-    (defun string-suffix-p (suffix string &optional ignore-case)
-      "Return non-nil if SUFFIX is a suffix of STRING.
-If IGNORE-CASE is non-nil, the comparison is done without paying
-attention to case differences."
-      (let ((start-pos (- (length string) (length suffix))))
-        (and (>= start-pos 0)
-             (eq t (compare-strings suffix nil nil
-                                    string start-pos nil ignore-case))))))
-
-  (defalias 'flycheck--format-message
-    (if (fboundp 'format-message) #'format-message #'format))
-
-  ;; TODO: Remove when dropping support for Emacs 24.3 and earlier
-  (unless (featurep 'subr-x)
-    ;; `subr-x' function for Emacs 24.3 and below
-    (defsubst string-join (strings &optional separator)
-      "Join all STRINGS using SEPARATOR."
-      (mapconcat 'identity strings separator))
-
-    (defsubst string-trim-left (string)
-      "Remove leading whitespace from STRING."
-      (if (string-match "\\`[ \t\n\r]+" string)
-          (replace-match "" t t string)
-        string))
-
-    (defsubst string-trim-right (string)
-      "Remove trailing whitespace from STRING."
-      (if (string-match "[ \t\n\r]+\\'" string)
-          (replace-match "" t t string)
-        string))
-
-    (defsubst string-trim (string)
-      "Remove leading and trailing whitespace from STRING."
-      (string-trim-left (string-trim-right string)))
-
-    (defsubst string-empty-p (string)
-      "Check whether STRING is empty."
-      (string= string ""))))
-
 
 ;;; Customization
 (defgroup flycheck nil
   "Modern on-the-fly syntax checking for GNU Emacs."
   :prefix "flycheck-"
   :group 'tools
-  :link '(url-link :tag "Website" "http://www.flycheck.org")
+  :link '(url-link :tag "Website" "https://www.flycheck.org")
   :link '(url-link :tag "Github" "https://github.com/flycheck/flycheck"))
 
 (defgroup flycheck-config-files nil
@@ -179,10 +135,8 @@ attention to case differences."
     c/c++-gcc
     c/c++-cppcheck
     cfengine
-    chef-foodcritic
     coffee
     coffee-coffeelint
-    coq
     css-csslint
     css-stylelint
     cuda-nvcc
@@ -199,7 +153,6 @@ attention to case differences."
     eruby-ruumba
     fortran-gfortran
     go-gofmt
-    go-golint
     go-vet
     go-build
     go-test
@@ -208,6 +161,7 @@ attention to case differences."
     go-staticcheck
     groovy
     haml
+    haml-lint
     handlebars
     haskell-stack-ghc
     haskell-ghc
@@ -227,14 +181,17 @@ attention to case differences."
     lua
     markdown-markdownlint-cli
     markdown-mdl
+    markdown-pymarkdown
     nix
     nix-linter
     opam
     perl
     perl-perlcritic
+    perl-perlimports
     php
     php-phpmd
     php-phpcs
+    php-phpcs-changed
     processing
     proselint
     protobuf-protoc
@@ -243,28 +200,32 @@ attention to case differences."
     puppet-parser
     puppet-lint
     python-flake8
+    python-ruff
     python-pylint
     python-pycompile
     python-pyright
     python-mypy
     r-lintr
+    r
     racket
     rpm-rpmlint
     rst-sphinx
     rst
     ruby-rubocop
+    ruby-chef-cookstyle
     ruby-standard
     ruby-reek
-    ruby-rubylint
     ruby
     ruby-jruby
     rust-cargo
     rust
     rust-clippy
+    salt-lint
     scala
     scala-scalastyle
     scheme-chicken
     scss-lint
+    sass-stylelint
     scss-stylelint
     sass/scss-sass-lint
     sass
@@ -277,6 +238,7 @@ attention to case differences."
     slim
     slim-lint
     sql-sqlint
+    statix
     systemd-analyze
     tcl-nagelfar
     terraform
@@ -290,6 +252,7 @@ attention to case differences."
     vhdl-ghdl
     xml-xmlstarlet
     xml-xmllint
+    yaml-actionlint
     yaml-jsyaml
     yaml-ruby
     yaml-yamllint)
@@ -428,6 +391,18 @@ node `(elisp)Hooks'."
   :package-version '(flycheck . "0.13")
   :risky t)
 
+(defcustom flycheck-auto-display-errors-after-checking t
+  "Whether to automatically display errors at the current point after checking.
+
+When being set to `nil', it will prevent Flycheck from automatically displaying
+error messages. This setting is useful when Flycheck is used together with
+`flycheck-posframe', to prevent `flycheck-posframe' from repeatedly displaying
+errors at point."
+  :group 'flycheck
+  :type 'boolean
+  :package-version '(flycheck . "35")
+  :safe #'booleanp)
+
 (defcustom flycheck-display-errors-delay 0.9
   "Delay in seconds before displaying errors at point.
 
@@ -454,6 +429,18 @@ If set to nil, do not display errors at all."
   :package-version '(flycheck . "0.13")
   :risky t)
 
+(defcustom flycheck-clear-displayed-errors-function #'flycheck-clear-displayed-error-messages
+  "Function to hide error message displayed by `flycheck-display-errors-function'.
+
+If set to a function, it will be called with no arguments to
+clear all displayed errors at point."
+  :group 'flycheck
+  :type '(choice (const :tag "Clear displayed error messages"
+                        flycheck-clear-displayed-error-messages)
+                 (function :tag "Clear displayed errors function"))
+  :package-version '(flycheck . "34.2")
+  :risky t)
+
 (defcustom flycheck-help-echo-function #'flycheck-help-echo-all-error-messages
   "Function to compute the contents of the error tooltips.
 
@@ -1164,6 +1151,12 @@ Set this variable to nil to disable the mode line completely."
   :risky t
   :package-version '(flycheck . "0.20"))
 
+(defcustom flycheck-mode-line-color t
+  "Use colors for Flycheck mode line status."
+  :group 'flycheck
+  :type 'boolean
+  :package-version '(flycheck . "35"))
+
 (defcustom flycheck-mode-line-prefix "FlyC"
   "Base mode line lighter for Flycheck.
 
@@ -1176,6 +1169,12 @@ function must be updated to use this variable."
   :type 'string
   :package-version '(flycheck . "26"))
 
+(defcustom flycheck-mode-success-indicator ":0"
+  "Success indicator appended to `flycheck-mode-line-prefix'."
+  :group 'flycheck
+  :type 'string
+  :package-version '(flycheck . "35"))
+
 (defcustom flycheck-error-list-mode-line
   `(,(propertized-buffer-identification "%12b")
     " for buffer "
@@ -1225,7 +1224,7 @@ Only has effect when variable `global-flycheck-mode' is non-nil."
 ;; Add built-in functions to our hooks, via `add-hook', to make sure that our
 ;; functions are really present, even if the variable was implicitly defined by
 ;; another call to `add-hook' that occurred before Flycheck was loaded.  See
-;; http://lists.gnu.org/archive/html/emacs-devel/2015-02/msg01271.html for why
+;; https://lists.gnu.org/archive/html/emacs-devel/2015-02/msg01271.html for why
 ;; we don't initialize the hook variables right away.  We append our own
 ;; functions, because a user likely expects that their functions come first,
 ;; even if they added them before Flycheck was loaded.
@@ -1250,6 +1249,7 @@ Only has effect when variable `global-flycheck-mode' is non-nil."
                             flycheck-checkers))]
      ["Check current buffer" flycheck-buffer flycheck-mode]
      ["Clear errors in buffer" flycheck-clear t]
+     ["Run checker as compile command" flycheck-compile flycheck-mode]
      "---"
      ["Go to next error" flycheck-next-error flycheck-mode]
      ["Go to previous error" flycheck-previous-error flycheck-mode]
@@ -1267,12 +1267,32 @@ Only has effect when variable `global-flycheck-mode' is non-nil."
      ["Describe syntax checker" flycheck-describe-checker t]
      ["Verify setup" flycheck-verify-setup t]
      ["Show Flycheck version" flycheck-version t]
-     ["Read the Flycheck manual" flycheck-info t]))
+     ["Flycheck quick help" flycheck-quick-help t]
+     ["Read the Flycheck manual" flycheck-manual t]))
   "Menu of command `flycheck-mode'.")
 
 (easy-menu-add-item nil '("Tools") flycheck-mode-menu-map "Spell Checking")
 
 
+
+(defconst flycheck-version "35.0-snapshot"
+  "The current version of Flycheck.
+
+Should be kept in sync with the package version metadata.
+Used only when `package-get-function' is not available
+or fails.")
+
+(defun flycheck--pkg-version ()
+  "Extract FLYCHECK's package version from its package metadata."
+  ;; Use `cond' below to avoid a compiler unused return value warning
+  ;; when `package-get-version' returns nil. See #3181.
+  (cond ((fboundp 'package-get-version)
+         (package-get-version))
+        ((fboundp 'pkg-info-version-info)
+         (pkg-info-version-info 'flycheck))
+        (t
+         flycheck-version)))
+
 ;;; Version information, manual and loading of Flycheck
 (defun flycheck-version (&optional show-version)
   "Get the Flycheck version as string.
@@ -1287,7 +1307,7 @@ If the version number could not be determined, signal an error,
 if called interactively, or if SHOW-VERSION is non-nil, otherwise
 just return nil."
   (interactive (list t))
-  (let ((version (pkg-info-version-info 'flycheck)))
+  (let ((version (flycheck--pkg-version)))
     (when show-version
       (message "Flycheck version: %s" version))
     version))
@@ -1304,7 +1324,43 @@ just return nil."
 (defun flycheck-manual ()
   "Open the Flycheck manual."
   (interactive)
-  (browse-url "http://www.flycheck.org"))
+  (browse-url "https://www.flycheck.org"))
+
+;;;###autoload
+(defun flycheck-quick-help ()
+  "Display brief Flycheck help."
+  (interactive)
+  (with-current-buffer (get-buffer-create "*flycheck-quick-help*")
+    (with-help-window (current-buffer)
+      (flycheck-mode) ;; so that we can exapnd \\[flycheck-<function>]
+      (let ((help
+             (substitute-command-keys
+        "Flycheck automatically runs checks on writable files when changed.
+Mode line status for the current buffer:
+  FlyC        Not been checked yet
+  FlyC*       Flycheck is running
+  FlyC:0      Last check resulted in no errors and no warnings
+  FlyC:3|5    Checker reported three errors and five warnings
+  FlyC-       No checker available
+  FlyC!       The checker crashed
+  FlyC.       The last syntax check was manually interrupted
+  FlyC?       The checker did something unexpected
+
+Key bindings:
+  \\[flycheck-buffer]     Check current buffer
+  \\[flycheck-clear]     Clear errors in current buffer
+  \\[flycheck-compile]   Run checker as compile command
+
+  \\[flycheck-next-error]     Next error
+  \\[flycheck-previous-error]     Previous error
+  \\[flycheck-list-errors]     List all errors
+
+  \\[flycheck-copy-errors-as-kill]   Copy error messages at point
+  \\[flycheck-display-error-at-point]     Explain error at point
+")))
+        (help-mode)
+        (read-only-mode 0)
+        (insert help)))))
 
 (define-obsolete-function-alias 'flycheck-info
   'flycheck-manual "Flycheck 26" "Open the Flycheck manual.")
@@ -1621,14 +1677,14 @@ Always return the name of the corresponding source file, never
 any byte-compiled file.
 
 Return nil, if the currently loaded file cannot be determined."
-  (-when-let* ((this-file (cond
-                           (load-in-progress load-file-name)
-                           ((bound-and-true-p byte-compile-current-file))
-                           (t (buffer-file-name))))
-               ;; A best guess for the source file of a compiled library. Works
-               ;; well in most cases, and especially for ELPA packages
-               (source-file (concat (file-name-sans-extension this-file)
-                                    ".el")))
+  (when-let* ((this-file (cond
+                          (load-in-progress load-file-name)
+                          ((bound-and-true-p byte-compile-current-file))
+                          (t (buffer-file-name))))
+              ;; A best guess for the source file of a compiled library. Works
+              ;; well in most cases, and especially for ELPA packages
+              (source-file (concat (file-name-sans-extension this-file)
+                                   ".el")))
     (when (file-exists-p source-file)
       source-file)))
 
@@ -2593,7 +2649,7 @@ return value is a list of checkers, not including CHECKER."
 
 (defun flycheck--verify-next-checkers (checker)
   "Return a verification result for the next checkers of CHECKER."
-  (-when-let (next (flycheck-get-next-checkers checker))
+  (when-let (next (flycheck-get-next-checkers checker))
     (list
      (flycheck-verification-result-new
       :label "next checkers"
@@ -2645,7 +2701,7 @@ to enable disabled checkers.")))
       (fill-region-as-paragraph (point) end)))
 
   (princ "\n\n--------------------\n\n")
-  (princ (format "Flycheck version: %s\n" (flycheck-version)))
+  (princ (format "Flycheck version: %s\n" (flycheck--pkg-version)))
   (princ (format "Emacs version:    %s\n" emacs-version))
   (princ (format "System:           %s\n" system-configuration))
   (princ (format "Window system:    %S\n" window-system)))
@@ -2925,7 +2981,7 @@ Slots:
     ;; the focus hooks only work on Emacs 24.4 and upwards, but since undefined
     ;; hooks are perfectly ok we don't need a version guard here.  They'll just
     ;; not work silently.
-    (post-command-hook . flycheck-maybe-display-error-at-point-soon)
+    (post-command-hook . flycheck-display-error-at-point-soon)
     (focus-in-hook     . flycheck-display-error-at-point-soon)
     (focus-out-hook    . flycheck-cancel-error-display-error-at-point-timer)
     (post-command-hook . flycheck-hide-error-buffer)
@@ -2958,10 +3014,11 @@ Flycheck displays its status in the mode line.  In the default
 configuration, it looks like this:
 
 `FlyC'     This buffer has not been checked yet.
-`FlyC-'    Flycheck doesn't have a checker for this buffer.
 `FlyC*'    Flycheck is running.  Expect results soon!
-`FlyC:3|2' This buffer contains three warnings and two errors.
+`FlyC:0'   Last check resulted in no errors and no warnings.
+`FlyC:3|5' This buffer contains three errors and five warnings.
            Use `\\[flycheck-list-errors]' to see the list.
+`FlyC-'    Flycheck doesn't have a checker for this buffer.
 
 You may also see the following icons:
 `FlyC!'    The checker crashed.
@@ -3290,7 +3347,8 @@ WORKING-DIR."
         (flycheck-delete-marked-overlays)
         (flycheck-error-list-refresh)
         (run-hooks 'flycheck-after-syntax-check-hook)
-        (when (eq (current-buffer) (window-buffer))
+        (when (and flycheck-auto-display-errors-after-checking
+                   (eq (current-buffer) (window-buffer)))
           (flycheck-display-error-at-point))
         ;; Immediately try to run any pending deferred syntax check, which
         ;; were triggered by intermediate automatic check event, to make sure
@@ -3329,6 +3387,7 @@ current syntax check."
     (flycheck-stop))
   (flycheck-delete-all-overlays)
   (flycheck-clear-errors)
+  (flycheck-clear-displayed-error-messages)
   (flycheck-error-list-refresh)
   (flycheck-hide-error-buffer))
 
@@ -3743,10 +3802,10 @@ Return a cons cell `(BEG . END)'.  If the input range is empty,
 it is expanded to cover at least one character so that END is
 always greater than BEG.  If ERR doesn't specify an end-column
 return nil."
-  (-if-let* ((line (flycheck-error-line err))
-             (column (flycheck-error-column err))
-             (end-line (or (flycheck-error-end-line err) line))
-             (end-column (flycheck-error-end-column err)))
+  (if-let* ((line (flycheck-error-line err))
+            (column (flycheck-error-column err))
+            (end-line (or (flycheck-error-end-line err) line))
+            (end-column (flycheck-error-end-column err)))
       ;; Ignoring fields speeds up calls to `line-end-position'.
       (let* ((inhibit-field-text-motion t)
              (beg (flycheck-line-column-to-position line column))
@@ -3873,8 +3932,8 @@ beginning position)."
          (other-file-p (and fname (not (equal fname (buffer-file-name))))))
     (concat (and other-file-p (format "In %S:\n" (file-relative-name fname)))
             (and include-snippet
-                 (-when-let* ((snippet (flycheck-error-format-snippet err)))
-                   (flycheck--format-message "`%s': " snippet)))
+                 (when-let* ((snippet (flycheck-error-format-snippet err)))
+                   (format-message "`%s': " snippet)))
             (or (flycheck-error-message err)
                 (format "Unknown %S" (flycheck-error-level err)))
             (and id (format " [%s]" id)))))
@@ -3995,7 +4054,7 @@ name of an error is nil fill in the result of function
 Return ERRORS, modified in-place."
   (seq-do (lambda (err)
             (setf (flycheck-error-filename err)
-                  (-if-let (filename (flycheck-error-filename err))
+                  (if-let (filename (flycheck-error-filename err))
                       (expand-file-name filename directory)
                     (buffer-file-name))))
           errors)
@@ -4117,19 +4176,29 @@ refresh the mode line."
 
 STATUS defaults to `flycheck-last-status-change' if omitted or
 nil."
-  (let ((text (pcase (or status flycheck-last-status-change)
-                (`not-checked "")
-                (`no-checker "-")
-                (`running "*")
-                (`errored "!")
-                (`finished
-                 (let-alist (flycheck-count-errors flycheck-current-errors)
-                   (if (or .error .warning)
-                       (format ":%s|%s" (or .error 0) (or .warning 0))
-                     "")))
-                (`interrupted ".")
-                (`suspicious "?"))))
-    (concat " " flycheck-mode-line-prefix text)))
+  (let* ((current-status (or status flycheck-last-status-change))
+         (indicator (pcase current-status
+                      (`not-checked "")
+                      (`no-checker "-")
+                      (`running "*")
+                      (`errored "!")
+                      (`finished
+                       (let-alist (flycheck-count-errors flycheck-current-errors)
+                         (if (or .error .warning)
+                             (format ":%s|%s" (or .error 0) (or .warning 0))
+                           flycheck-mode-success-indicator)))
+                      (`interrupted ".")
+                      (`suspicious "?")))
+         (face (when flycheck-mode-line-color
+                 (pcase current-status
+                   (`errored 'error)
+                   (`finished
+                    (let-alist (flycheck-count-errors flycheck-current-errors)
+                      (if (or .error .warning) 'error 'success))))))
+         (text (format " %s%s" flycheck-mode-line-prefix indicator)))
+    (when face
+      (setq text (propertize text 'face face)))
+    text))
 
 
 ;;; Error levels
@@ -4516,7 +4585,7 @@ Return ERRORS."
 
 Return ERRORS."
   (dolist (err errors)
-    (-when-let (message (flycheck-error-message err))
+    (when-let (message (flycheck-error-message err))
       (setf (flycheck-error-message err)
             (replace-regexp-in-string (rx (one-or-more (any space "\n" "\r")))
                                       " " message 'fixed-case 'literal))))
@@ -4531,7 +4600,7 @@ lines accordingly.
 
 Return ERRORS, with in-place modifications."
   (dolist (err errors)
-    (-when-let (message (flycheck-error-message err))
+    (when-let (message (flycheck-error-message err))
       (with-temp-buffer
         (insert message)
         ;; Determine the indentation offset
@@ -4793,11 +4862,11 @@ errors.  Arguments WINDOW, OBJECT and POS are as described in
 info node `(elisp)Special properties', as this function is
 intended to be used as the \\='help-echo property of flycheck error
 overlays."
-  (-when-let (buf (cond ((bufferp object) object)
-                        ((overlayp object) (overlay-buffer object))))
+  (when-let (buf (cond ((bufferp object) object)
+                       ((overlayp object) (overlay-buffer object))))
     (with-current-buffer buf
-      (-when-let* ((fn flycheck-help-echo-function)
-                   (errs (flycheck-overlay-errors-at pos)))
+      (when-let* ((fn flycheck-help-echo-function)
+                  (errs (flycheck-overlay-errors-at pos)))
         (propertize (funcall fn errs) 'help-echo-inhibit-substitution t)))))
 
 (defun flycheck-help-echo-all-error-messages (errs)
@@ -4877,7 +4946,7 @@ overlays."
 ERR is also interesting (the function returns true) if there are
 no errors as or more severe than `flycheck-navigation-minimum-level'."
   (when (flycheck-error-p err)
-    (-if-let (min-level flycheck-navigation-minimum-level)
+    (if-let (min-level flycheck-navigation-minimum-level)
         (or (<= (flycheck-error-level-severity min-level)
                 (flycheck-error-level-severity (flycheck-error-level err)))
             (not (flycheck-has-current-errors-p min-level)))
@@ -4939,8 +5008,8 @@ beginning of the buffer, otherwise advance from the current
 position.
 
 Intended for use with `next-error-function'."
-  (-if-let* ((pos (flycheck-next-error-pos n reset))
-             (err (get-char-property pos 'flycheck-error)))
+  (if-let* ((pos (flycheck-next-error-pos n reset))
+            (err (get-char-property pos 'flycheck-error)))
       (flycheck-jump-to-error err)
     (user-error "No more Flycheck errors")))
 
@@ -5044,11 +5113,8 @@ message to stretch arbitrarily far."
         ;; `revert-buffer' updates the mode line for us, so all we need to do is
         ;; set the corresponding mode line construct.
         mode-line-buffer-identification flycheck-error-list-mode-line)
-  ;; Guard `truncate-string-ellipsis' for Emacs 24.
-  ;; TODO: Remove when dropping Emacs 24 compatibility
-  (when (boundp 'truncate-string-ellipsis)
-    ;; See https://github.com/flycheck/flycheck/issues/1101
-    (setq-local truncate-string-ellipsis "…"))
+  ;; See https://github.com/flycheck/flycheck/issues/1101
+  (setq-local truncate-string-ellipsis "…")
   (tabulated-list-init-header))
 
 (defvar-local flycheck-error-list-source-buffer nil
@@ -5177,8 +5243,8 @@ ensure that they line up properly once the message is displayed."
 
 (defun flycheck-error-list-entries ()
   "Create the entries for the error list."
-  (-when-let* ((errors (flycheck-error-list-current-errors))
-               (filtered (flycheck-error-list-apply-filter errors)))
+  (when-let* ((errors (flycheck-error-list-current-errors))
+              (filtered (flycheck-error-list-apply-filter errors)))
     (seq-map #'flycheck-error-list-make-entry filtered)))
 
 (defun flycheck-error-list-entry-< (entry1 entry2)
@@ -5228,7 +5294,7 @@ mode line indication of `flycheck-error-list-mode'."
 
 ALL-FRAMES specifies the frames to consider, as in
 `get-buffer-window-list'."
-  (-when-let (buf (get-buffer flycheck-error-list-buffer))
+  (when-let (buf (get-buffer flycheck-error-list-buffer))
     (get-buffer-window-list buf nil all-frames)))
 
 (defun flycheck-get-error-list-window (&optional all-frames)
@@ -5236,7 +5302,7 @@ ALL-FRAMES specifies the frames to consider, as in
 
 ALL-FRAMES specifies the frames to consider, as in
 `get-buffer-window'."
-  (-when-let (buf (get-buffer flycheck-error-list-buffer))
+  (when-let (buf (get-buffer flycheck-error-list-buffer))
     (get-buffer-window buf all-frames)))
 
 (defun flycheck-error-list-recenter-at (pos)
@@ -5257,7 +5323,7 @@ list."
   ;; select this window while reverting, because Tabulated List mode attempts to
   ;; recenter the error at the old location, so it must have the proper window
   ;; selected.
-  (-when-let (window (flycheck-get-error-list-window t))
+  (when-let (window (flycheck-get-error-list-window t))
     (with-selected-window window
       (revert-buffer))
     (run-hooks 'flycheck-error-list-after-refresh-hook)
@@ -5302,8 +5368,8 @@ Interactively, or with non-nil REFRESH, refresh the error list."
 
 (defun flycheck-error-list-apply-filter (errors)
   "Filter ERRORS according to `flycheck-error-list-minimum-level'."
-  (-if-let* ((min-level flycheck-error-list-minimum-level)
-             (min-severity (flycheck-error-level-severity min-level)))
+  (if-let* ((min-level flycheck-error-list-minimum-level)
+            (min-severity (flycheck-error-level-severity min-level)))
       (seq-filter (lambda (err) (>= (flycheck-error-level-severity
                                      (flycheck-error-level err))
                                     min-severity))
@@ -5315,7 +5381,7 @@ Interactively, or with non-nil REFRESH, refresh the error list."
 
 POS defaults to `point'."
   (interactive)
-  (-when-let* ((error (tabulated-list-get-id pos)))
+  (when-let* ((error (tabulated-list-get-id pos)))
     (flycheck-jump-to-error error)))
 
 (defun flycheck-jump-to-error (error)
@@ -5365,11 +5431,11 @@ POS defaults to `point'."
 
 POS defaults to `point'."
   (interactive)
-  (-when-let* ((error (tabulated-list-get-id pos))
-               (explainer (flycheck-checker-get (flycheck-error-checker error)
-                                                'error-explainer)))
+  (when-let* ((error (tabulated-list-get-id pos))
+              (explainer (flycheck-checker-get (flycheck-error-checker error)
+                                               'error-explainer)))
     (flycheck-error-with-buffer error
-      (-when-let (explanation (funcall explainer error))
+      (when-let (explanation (funcall explainer error))
         (flycheck-display-error-explanation explanation)))))
 
 (defun flycheck-error-list-next-error-pos (pos &optional n)
@@ -5493,6 +5559,11 @@ non-nil."
   (when flycheck-display-errors-function
     (funcall flycheck-display-errors-function errors)))
 
+(defun flycheck-clear-displayed-errors ()
+  "Clear errors using `flycheck-clear-displayed-errors-function'."
+  (when flycheck-clear-displayed-errors-function
+    (funcall flycheck-clear-displayed-errors-function)))
+
 (defvar-local flycheck-display-error-at-point-timer nil
   "Timer to automatically show errors.")
 
@@ -5502,40 +5573,27 @@ non-nil."
     (cancel-timer flycheck-display-error-at-point-timer)
     (setq flycheck-display-error-at-point-timer nil)))
 
-(defun flycheck--error-display-tick ()
-  "Return point and tick counter of current buffer."
-  (cons (point) (buffer-modified-tick)))
-
-(defvar-local flycheck--last-error-display-tick nil
-  "Value of `flycheck--error-display-tick' when errors were last displayed.")
-
 (defun flycheck-display-error-at-point ()
-  "Display all the error messages at point."
+  "Display all the error messages at point.
+
+If there are no errors, clears the error messages at point."
   (interactive)
   ;; This function runs from a timer, so we must take care to not ignore any
   ;; errors
   (with-demoted-errors "Flycheck error display error: %s"
     (flycheck-cancel-error-display-error-at-point-timer)
-    (setq flycheck--last-error-display-tick (flycheck--error-display-tick))
     (when flycheck-mode
-      (-when-let (errors (flycheck-overlay-errors-at (point)))
-        (flycheck-display-errors errors)))))
+      (let ((errors (flycheck-overlay-errors-at (point))))
+        (if errors
+            (flycheck-display-errors errors)
+          (flycheck-clear-displayed-errors))))))
 
 (defun flycheck-display-error-at-point-soon ()
   "Display error messages at point, with a delay."
-  (setq flycheck--last-error-display-tick nil)
-  (flycheck-maybe-display-error-at-point-soon))
-
-(defun flycheck-maybe-display-error-at-point-soon ()
-  "Display error message at point with a delay, unless already displayed."
   (flycheck-cancel-error-display-error-at-point-timer)
-  (when (and (not (equal flycheck--last-error-display-tick
-                         (setq flycheck--last-error-display-tick
-                               (flycheck--error-display-tick))))
-             (flycheck-overlays-at (point)))
-    (setq flycheck-display-error-at-point-timer
-          (run-at-time flycheck-display-errors-delay nil
-                       'flycheck-display-error-at-point))))
+  (setq flycheck-display-error-at-point-timer
+        (run-at-time flycheck-display-errors-delay nil
+                     'flycheck-display-error-at-point)))
 
 
 ;;; Functions to display errors
@@ -5560,6 +5618,14 @@ and if the echo area is not occupied by minibuffer input."
   "Flycheck error messages"
   "Major mode for extended error messages.")
 
+(defvar flycheck--last-displayed-message nil
+  "Reference to the last displayed message so it can be cleared.
+
+This value is the return value from `display-message-or-buffer',
+thus it can be a string or a window.
+
+See `flycheck-clear-displayed-error-messages'.")
+
 (defun flycheck-display-error-messages (errors)
   "Display the messages of ERRORS.
 
@@ -5573,15 +5639,17 @@ information.
 In the latter case, show messages in the buffer denoted by
 variable `flycheck-error-message-buffer'."
   (when (and errors (flycheck-may-use-echo-area-p))
-    (let ((message (flycheck-help-echo-all-error-messages errors)))
-      (display-message-or-buffer
-       message flycheck-error-message-buffer 'not-this-window)
+    (let* ((message (flycheck-help-echo-all-error-messages errors))
+           (retval (display-message-or-buffer
+                    message flycheck-error-message-buffer 'not-this-window)))
       ;; We cannot rely on `display-message-or-buffer' returning the right
       ;; window. See URL `https://github.com/flycheck/flycheck/issues/1643'.
-      (-when-let (buf (get-buffer flycheck-error-message-buffer))
+      (when-let (buf (get-buffer flycheck-error-message-buffer))
         (with-current-buffer buf
           (unless (derived-mode-p 'flycheck-error-message-mode)
-            (flycheck-error-message-mode)))))))
+            (flycheck-error-message-mode))))
+      (setq flycheck--last-displayed-message retval)
+      retval)))
 
 (defun flycheck-display-error-messages-unless-error-list (errors)
   "Show messages of ERRORS unless the error list is visible.
@@ -5596,14 +5664,22 @@ the current frame."
   "Hide the Flycheck error buffer if necessary.
 
 Hide the error buffer if there is no error under point."
-  (-when-let* ((buffer (flycheck-error-message-buffer))
-               (window (get-buffer-window buffer)))
+  (when-let* ((buffer (flycheck-error-message-buffer))
+              (window (get-buffer-window buffer)))
     (unless (flycheck-overlays-at (point))
       ;; save-selected-window prevents `quit-window' from changing the current
       ;; buffer (see https://github.com/flycheck/flycheck/issues/648).
       (save-selected-window
         (quit-window nil window)))))
 
+(defun flycheck-clear-displayed-error-messages ()
+  "Clear error messages displayed by `flycheck-display-error-messages'."
+  (when flycheck--last-displayed-message
+    (if (and (stringp flycheck--last-displayed-message)
+             (equal (current-message) flycheck--last-displayed-message))
+        (message nil)
+      (flycheck-hide-error-buffer))))
+
 
 ;;; Working with errors
 (defun flycheck-copy-errors-as-kill (pos &optional formatter)
@@ -5635,16 +5711,16 @@ with a non-nil `:error-explainer' function defined in its
 checker.  The `:error-explainer' function is then called with
 this error to produce the explanation to display."
   (interactive)
-  (-when-let* ((first-error
-                ;; Get the first error at point that has an `error-explainer'.
-                (seq-find (lambda (error)
-                            (flycheck-checker-get
-                             (flycheck-error-checker error) 'error-explainer))
-                          (flycheck-overlay-errors-at (point))))
-               (explainer
-                (flycheck-checker-get (flycheck-error-checker first-error)
-                                      'error-explainer))
-               (explanation (funcall explainer first-error)))
+  (when-let* ((first-error
+               ;; Get the first error at point that has an `error-explainer'.
+               (seq-find (lambda (error)
+                           (flycheck-checker-get
+                            (flycheck-error-checker error) 'error-explainer))
+                         (flycheck-overlay-errors-at (point))))
+              (explainer
+               (flycheck-checker-get (flycheck-error-checker first-error)
+                                     'error-explainer))
+              (explanation (funcall explainer first-error)))
     (flycheck-display-error-explanation explanation)))
 
 (defconst flycheck-explain-error-buffer "*Flycheck error explanation*"
@@ -5800,6 +5876,21 @@ of command checkers is `flycheck-sanitize-errors'.
      If this property is given and has a non-nil value, send the
      contents of the buffer on standard input.
 
+     Some checkers that support reading from standard input have
+     a separate flag to indicate the name of the file whose
+     contents are being passed on standard input (typically
+     `stdin-filename').  In that case, use the `(option)' form in
+     `:command' to pass the value of variable `buffer-file-name'
+     when the current buffer has a file name (that is,
+     use `option \"--stdin-file-name\" buffer-file-name').
+
+     For buffers not backed by files, checkers that support input
+     on stdin typically report a file name like `-' or `<stdin>'.
+     Make sure your error parser or patterns expect these file
+     names (for example, use `(or \"<stdin>\" (file-name))') or
+     call `flycheck-remove-error-file-names' in a custom
+     `:error-filter'.
+
      Defaults to nil.
 
 Note that you may not give `:start', `:interrupt', and
@@ -5911,7 +6002,7 @@ executable cannot be found, and return a numeric exit status or a
 signal description string otherwise.  CHECKER's input is taken
 from INFILE, and its output is sent to DESTINATION, as in
 `call-process'."
-  (-if-let (executable (flycheck-find-checker-executable checker))
+  (if-let (executable (flycheck-find-checker-executable checker))
       (condition-case err
           (apply #'call-process executable infile destination nil args)
         (error (when error (signal (car err) (cdr err)))))
@@ -6089,27 +6180,27 @@ are substituted within the body of cells!"
        (list (make-temp-name (expand-file-name "flycheck" directory)))))
     (`null-device (list null-device))
     (`(config-file ,option-name ,file-name-var)
-     (-when-let* ((value (symbol-value file-name-var))
-                  (file-name (flycheck-locate-config-file value checker)))
+     (when-let* ((value (symbol-value file-name-var))
+                 (file-name (flycheck-locate-config-file value checker)))
        (flycheck-prepend-with-option option-name (list file-name))))
     (`(config-file ,option-name ,file-name-var ,prepend-fn)
-     (-when-let* ((value (symbol-value file-name-var))
-                  (file-name (flycheck-locate-config-file value checker)))
+     (when-let* ((value (symbol-value file-name-var))
+                 (file-name (flycheck-locate-config-file value checker)))
        (flycheck-prepend-with-option option-name (list file-name) prepend-fn)))
     (`(option ,option-name ,variable)
-     (-when-let (value (symbol-value variable))
+     (when-let (value (symbol-value variable))
        (unless (stringp value)
          (error "Value %S of %S for option %s is not a string"
                 value variable option-name))
        (flycheck-prepend-with-option option-name (list value))))
     (`(option ,option-name ,variable ,prepend-fn)
-     (-when-let (value (symbol-value variable))
+     (when-let (value (symbol-value variable))
        (unless (stringp value)
          (error "Value %S of %S for option %s is not a string"
                 value variable option-name))
        (flycheck-prepend-with-option option-name (list value) prepend-fn)))
     (`(option ,option-name ,variable ,prepend-fn ,filter)
-     (-when-let (value (funcall filter (symbol-value variable)))
+     (when-let (value (funcall filter (symbol-value variable)))
        (unless (stringp value)
          (error "Value %S of %S (filter: %S) for option %s is not a string"
                 value variable filter option-name))
@@ -6567,8 +6658,8 @@ directory of the current buffer and all ancestors thereof (see
 absolute path.  Otherwise return nil.
 
 _CHECKER is ignored."
-  (-when-let* ((basefile (buffer-file-name))
-               (directory (locate-dominating-file basefile filename)))
+  (when-let* ((basefile (buffer-file-name))
+              (directory (locate-dominating-file basefile filename)))
     (expand-file-name filename directory)))
 
 (defun flycheck-locate-config-file-home (filename _checker)
@@ -6657,7 +6748,7 @@ SEPARATOR is ignored in this case."
   (let ((filter (or filter #'identity))
         (separator (or separator ",")))
     (if (listp value)
-        (-when-let (value (delq nil (seq-map filter value)))
+        (when-let (value (delq nil (seq-map filter value)))
           (string-join value separator))
       (funcall filter value))))
 
@@ -6768,8 +6859,12 @@ Instead of highlighting errors in the buffer, this command pops
 up a separate buffer with the entire output of the syntax checker
 tool, just like `compile' (\\[compile])."
   (interactive
-   (let ((default (flycheck-get-checker-for-buffer)))
-     (list (flycheck-read-checker "Run syntax checker as compile command: "
+   (let* ((default (flycheck-get-checker-for-buffer))
+          (prompt (concat
+                   "Run syntax checker as compile command"
+                   (when default (concat " [" (format "%S" default) "]"))
+                   ": ")))
+     (list (flycheck-read-checker prompt
                                   (when (flycheck-checker-get default 'command)
                                     default)
                                   'command))))
@@ -6809,7 +6904,7 @@ Make the file name of ERR absolute.  If the absolute file name of
 ERR is in BUFFER-FILES, replace it with the value of variable
 `buffer-file-name'."
   (flycheck-error-with-buffer err
-    (-when-let (filename (flycheck-error-filename err))
+    (when-let (filename (flycheck-error-filename err))
       (when (seq-some (apply-partially #'flycheck-same-files-p
                                        (expand-file-name filename cwd))
                       buffer-files)
@@ -6872,7 +6967,7 @@ checkers that have an option to output errors in this format.
 CHECKER and BUFFER denoted the CHECKER that returned OUTPUT and
 the BUFFER that was checked respectively.
 
-See URL `http://checkstyle.sourceforge.net/' for information
+See URL `https://checkstyle.sourceforge.net/' for information
 about Checkstyle."
   (pcase (flycheck-parse-xml-string output)
     (`(checkstyle ,_ . ,file-nodes)
@@ -6908,7 +7003,7 @@ Parse Cppcheck XML v2 output.
 CHECKER and BUFFER denoted the CHECKER that returned OUTPUT and
 the BUFFER that was checked respectively.
 
-See URL `http://cppcheck.sourceforge.net/' for more information
+See URL `https://cppcheck.sourceforge.net/' for more information
 about Cppcheck."
   (pcase (flycheck-parse-xml-string output)
     (`(results ,_ . ,body)
@@ -6950,7 +7045,7 @@ about Cppcheck."
 CHECKER and BUFFER denoted the CHECKER that returned OUTPUT and
 the BUFFER that was checked respectively.
 
-See URL `http://phpmd.org/' for more information about phpmd."
+See URL `https://phpmd.org/' for more information about phpmd."
   (pcase (flycheck-parse-xml-string output)
     (`(pmd ,_ . ,body)
      (let (errors)
@@ -7507,7 +7602,7 @@ Uses the GNAT compiler from GCC.  See URL
 (flycheck-define-checker asciidoc
   "A AsciiDoc syntax checker using the AsciiDoc compiler.
 
-See URL `http://www.methods.co.nz/asciidoc'."
+See URL `https://www.methods.co.nz/asciidoc'."
   :command ("asciidoc" "-o" null-device "-")
   :standard-input t
   :error-patterns
@@ -7525,7 +7620,7 @@ See URL `http://www.methods.co.nz/asciidoc'."
 (flycheck-define-checker asciidoctor
   "An AsciiDoc syntax checker using the Asciidoctor compiler.
 
-See URL `http://asciidoctor.org'."
+See URL `https://asciidoctor.org'."
   :command ("asciidoctor" "-o" null-device "-")
   :standard-input t
   :error-patterns
@@ -7646,7 +7741,7 @@ See URL `https://github.com/bazelbuild/buildtools/blob/master/buildifier'."
   "Enable blocks in Clang.
 
 When non-nil, enable blocks in Clang with `-fblocks'.  See URL
-`http://clang.llvm.org/docs/BlockLanguageSpec.html' for more
+`https://clang.llvm.org/docs/BlockLanguageSpec.html' for more
 information about blocks."
   :type 'boolean
   :safe #'booleanp
@@ -7747,7 +7842,7 @@ The value of this variable is the name of a standard library as
 string, or nil to use the default standard library.
 
 Refer to the Clang manual at URL
-`http://clang.llvm.org/docs/UsersManual.html' for more
+`https://clang.llvm.org/docs/UsersManual.html' for more
 information about the standard library."
   :type '(choice (const :tag "Default standard library" nil)
                  (const "libc++")
@@ -7765,7 +7860,7 @@ recommended warnings and some extra warnings are enabled (as by
 `-Wall' and `-Wextra' respectively).
 
 Refer to the Clang manual at URL
-`http://clang.llvm.org/docs/UsersManual.html' for more
+`https://clang.llvm.org/docs/UsersManual.html' for more
 information about warnings."
   :type '(choice (const :tag "No additional warnings" nil)
                  (repeat :tag "Additional warnings"
@@ -7783,7 +7878,7 @@ explicitly determine the directory for quoted includes.
 
 This function determines the directory by looking at function
 `buffer-file-name', or if that is nil, at `default-directory'."
-  (-if-let (fn (buffer-file-name))
+  (if-let (fn (buffer-file-name))
       (file-name-directory fn)
     ;; If the buffer has no file name, fall back to its default directory
     default-directory))
@@ -7791,7 +7886,7 @@ This function determines the directory by looking at function
 (flycheck-define-checker c/c++-clang
   "A C/C++ syntax checker using Clang.
 
-See URL `http://clang.llvm.org/'."
+See URL `https://clang.llvm.org/'."
   :command ("clang"
             "-fsyntax-only"
             "-fno-color-diagnostics"    ; Do not include color codes in output
@@ -7999,7 +8094,7 @@ string is the name of an additional check to enable.  By default,
 all coding style checks are enabled.
 
 See section \"Enable message\" in the Cppcheck manual at URL
-`http://cppcheck.sourceforge.net/manual.pdf', and the
+`https://cppcheck.sourceforge.net/manual.pdf', and the
 documentation of the `--enable' option for more information,
 including a list of supported checks."
   :type '(repeat :tag "Additional checks"
@@ -8069,7 +8164,7 @@ Relative paths are relative to the file being checked."
 (flycheck-define-checker c/c++-cppcheck
   "A C/C++ checker using cppcheck.
 
-See URL `http://cppcheck.sourceforge.net/'."
+See URL `https://cppcheck.sourceforge.net/'."
   :command ("cppcheck" "--quiet" "--xml-version=2" "--inline-suppr"
             (option "--enable=" flycheck-cppcheck-checks concat
                     flycheck-option-comma-separated-list)
@@ -8101,45 +8196,6 @@ See URL `https://cfengine.com/'."
           ": error: " (message) line-end))
   :modes (cfengine-mode cfengine3-mode))
 
-(flycheck-def-option-var flycheck-foodcritic-tags nil chef-foodcritic
-  "A list of tags to select for Foodcritic.
-
-The value of this variable is a list of strings where each string
-is a tag expression describing Foodcritic rules to enable or
-disable, via the `--tags' option.  To disable a tag, prefix it
-with `~'."
-  :type '(repeat :tag "Tags" (string :tag "Tag expression"))
-  :safe #'flycheck-string-list-p
-  :package-version '(flycheck . "0.23"))
-
-(flycheck-define-checker chef-foodcritic
-  "A Chef cookbooks syntax checker using Foodcritic.
-
-See URL `http://www.foodcritic.io'."
-  ;; Use `source-inplace' to allow resource discovery with relative paths.
-  ;; foodcritic interprets these as relative to the source file, so we need to
-  ;; stay within the source tree.  See
-  ;; https://github.com/flycheck/flycheck/pull/556
-  :command ("foodcritic"
-            (option-list "--tags" flycheck-foodcritic-tags)
-            source-inplace)
-  :error-patterns
-  ((error line-start (id (one-or-more alnum)) ": "
-          (message) ": " (file-name) ":" line line-end))
-  :modes (enh-ruby-mode ruby-mode ruby-ts-mode)
-  :predicate
-  (lambda ()
-    (let ((parent-dir (file-name-directory
-                       (directory-file-name
-                        (expand-file-name default-directory)))))
-      (or
-       ;; Chef CookBook
-       ;; http://docs.opscode.com/chef/knife.html#id38
-       (locate-dominating-file parent-dir "recipes")
-       ;; Knife Solo
-       ;; http://matschaffer.github.io/knife-solo/#label-Init+command
-       (locate-dominating-file parent-dir "cookbooks")))))
-
 (flycheck-define-checker coffee
   "A CoffeeScript syntax checker using coffee.
 
@@ -8159,7 +8215,7 @@ See URL `https://coffeescript.org/'."
 (flycheck-define-checker coffee-coffeelint
   "A CoffeeScript style checker using coffeelint.
 
-See URL `http://www.coffeelint.org/'."
+See URL `https://www.coffeelint.org/'."
   :command
   ("coffeelint"
    (config-file "--file" flycheck-coffeelintrc)
@@ -8172,43 +8228,6 @@ See URL `http://www.coffeelint.org/'."
                             (flycheck-sanitize-errors errors))))
   :modes coffee-mode)
 
-(defun flycheck-coq-error-filter (errors)
-  "Sanitize Coq ERRORS and compute end-lines and end-columns."
-  (flycheck-increment-error-columns errors)
-  (dolist (err errors)
-    (setf (flycheck-error-message err)
-          (replace-regexp-in-string (rx (1+ (syntax whitespace)) line-end)
-                                    "" (flycheck-error-message err)
-                                    'fixedcase 'literal))
-    (-when-let* ((end-col (flycheck-error-end-column err)))
-      ;; Coq reports an offset (potentially past eol), not an end column
-      (let* ((line (flycheck-error-line err))
-             (end-lc (save-excursion
-                       (flycheck-goto-line line)
-                       (goto-char (+ (point) (1- end-col)))
-                       (flycheck-line-column-at-point))))
-        (setf (flycheck-error-end-line err) (car end-lc))
-        (setf (flycheck-error-end-column err) (cdr end-lc)))))
-  (flycheck-sanitize-errors errors))
-
-(flycheck-define-checker coq
-  "A Coq syntax checker using the Coq compiler.
-
-See URL `https://coq.inria.fr/'."
-  ;; We use coqtop in batch mode, because coqc is picky about file names.
-  :command ("coqtop" "-batch" "-load-vernac-source" source)
-  :error-patterns
-  ((error line-start "File \"" (file-name) "\", line " line
-          ", characters " column "-" end-column ":\n"
-          (or "Syntax error:" "Error:")
-          ;; Most Coq error messages span multiple lines, and end with a dot.
-          ;; There are simple one-line messages, too, though.
-          (message (or (and (one-or-more (or not-newline "\n")) ".")
-                       (one-or-more not-newline)))
-          line-end))
-  :error-filter flycheck-coq-error-filter
-  :modes coq-mode)
-
 (flycheck-define-checker css-csslint
   "A CSS syntax and style checker using csslint.
 
@@ -8221,11 +8240,15 @@ See URL `https://github.com/CSSLint/csslint'."
 (defconst flycheck-stylelint-args '("--formatter" "json")
   "Common arguments to stylelint invocations.")
 
-(flycheck-def-config-file-var flycheck-stylelintrc
-    (css-stylelint scss-stylelint less-stylelint) nil)
+;; Limit the length of the generated docstring by including only the first three
+;; checker symbols, otherwise emacs will complain about the docstring length
+;; and may refuse to compile the package.
+(let ((print-length 3))
+  (flycheck-def-config-file-var flycheck-stylelintrc
+      (css-stylelint scss-stylelint sass-stylelint less-stylelint) nil))
 
 (flycheck-def-option-var flycheck-stylelint-quiet
-    nil (css-stylelint scss-stylelint less-stylelint)
+    nil (css-stylelint scss-stylelint sass-stylelint less-stylelint)
   "Whether to run stylelint in quiet mode.
 
 When non-nil, enable quiet mode, via `--quiet'."
@@ -8269,7 +8292,7 @@ If the CHECKER throws an Error it returns an Error message with a stacktrace."
 CHECKER and BUFFER denoted the CHECKER that returned OUTPUT and
 the BUFFER that was checked respectively.
 
-See URL `http://stylelint.io/developer-guide/formatters/' for information
+See URL `https://stylelint.io/developer-guide/formatters/' for information
 about the JSON format of stylelint."
   (let ((json-object-type 'plist))
 
@@ -8322,19 +8345,54 @@ about the JSON format of stylelint."
       ;; Return the combined errors (deprecations, invalid options, warnings)
       (append deprecations invalid-options warnings))))
 
+(defun flycheck--stylelint-config-exists-p (checker)
+  "Whether there is a valid stylelint CHECKER config for the current buffer."
+  (eql 0 (flycheck-call-checker-process
+          checker nil nil nil
+          "--print-config" (or buffer-file-name "index.js"))))
+
+(defun flycheck--stylelint-get-major-version (checker)
+  "Return major version of stylelint CHECKER."
+  (let ((cb (current-buffer)))
+    (with-temp-buffer
+      (let ((temp-buffer (current-buffer)))
+        (with-current-buffer cb
+          (flycheck-call-checker-process
+           checker nil temp-buffer nil "--version"))
+        (string-to-number (car (split-string (buffer-string) "\\.")))))))
+
+(defun flycheck--stylelint-verify (checker)
+  "Verify stylelint setup for CHECKER."
+  (let ((have-config (flycheck--stylelint-config-exists-p checker)))
+    (list
+     (flycheck-verification-result-new
+      :label "configuration available"
+      :message (if have-config "yes" "no config file found")
+      :face (if have-config 'success '(bold error)))
+     (flycheck-verification-result-new
+      :label "stylecheck version"
+      :message (number-to-string (flycheck--stylelint-get-major-version checker))
+      :face 'success))))
+
 (flycheck-define-checker css-stylelint
   "A CSS syntax and style checker using stylelint.
 
-See URL `http://stylelint.io/'."
+See URL `https://stylelint.io/'."
   :command ("stylelint"
             (eval flycheck-stylelint-args)
             (option-flag "--quiet" flycheck-stylelint-quiet)
             (config-file "--config" flycheck-stylelintrc)
             "--stdin-filename" (eval (or (buffer-file-name) "style.css")))
   :standard-input t
+  :verify (lambda (_) (flycheck--stylelint-verify 'css-stylelint))
   :error-parser flycheck-parse-stylelint
   :predicate flycheck-buffer-nonempty-p
-  :modes (css-mode css-ts-mode))
+  :modes (css-mode css-ts-mode)
+  :error-explainer
+  (lambda (err)
+    (let ((error-code (flycheck-error-id err))
+          (url "https://stylelint.io/user-guide/rules/%s"))
+      (and error-code `(url . ,(format url error-code))))))
 
 (flycheck-def-option-var flycheck-cuda-language-standard nil cuda-nvcc
   "Our CUDA Language Standard."
@@ -8369,6 +8427,24 @@ A list of strings to pass to cuda, a la flycheck-clang"
   :safe #'flycheck-string-list-p
   :package-version '(flycheck . "32"))
 
+(flycheck-def-option-var flycheck-cuda-relaxed-constexpr nil cuda-nvcc
+  "Enable calling host constexpr from device function for nvcc.
+
+When non-nil, enable experimental calling of a constexpr __host__
+function from a __device__ function."
+  :type 'boolean
+  :safe #'booleanp
+  :package-version '(flycheck . "35"))
+
+(flycheck-def-option-var flycheck-cuda-extended-lambda nil cuda-nvcc
+  "Enable annotating lambda functions with __host__ or __device__.
+
+When non-nil, enable experimental compilation of __host__ and
+__device__ lambda functions."
+  :type 'boolean
+  :safe #'booleanp
+  :package-version '(flycheck . "35"))
+
 (flycheck-define-checker cuda-nvcc
   "A CUDA C/C++ syntax checker using nvcc.
 
@@ -8379,6 +8455,8 @@ See URL `https://developer.nvidia.com/cuda-llvm-compiler'."
             "--x=cu" ;; explicitly specify it's a CUDA language file
             "-rdc=true" ;; Allow linking with external cuda funcions
             (option "-std=" flycheck-cuda-language-standard concat)
+            (option-flag "--expt-relaxed-constexpr" flycheck-cuda-relaxed-constexpr)
+            (option-flag "--expt-extended-lambda" flycheck-cuda-extended-lambda)
             (option-list "-include" flycheck-cuda-includes)
             (option-list "-gencode" flycheck-cuda-gencodes)
             (option-list "-D" flycheck-cuda-definitions concat)
@@ -8483,7 +8561,7 @@ Requires DMD 2.066 or newer.  See URL `https://dlang.org/'."
 (flycheck-define-checker dockerfile-hadolint
   "A Dockerfile syntax checker using the hadolint.
 
-See URL `http://github.com/hadolint/hadolint/'."
+See URL `https://github.com/hadolint/hadolint/'."
   :command ("hadolint" "--no-color" "-")
   :standard-input t
   :error-patterns
@@ -8521,7 +8599,7 @@ When non-nil, pass the `--strict' flag to credo."
 (flycheck-define-checker elixir-credo
   "An Elixir checker for static code analysis using Credo.
 
-See `http://credo-ci.org/'."
+See `https://credo-ci.org/'."
   :command ("mix" "credo"
             (option-flag "--strict" flycheck-elixir-credo-strict)
             "--format" "flycheck"
@@ -8908,7 +8986,7 @@ Relative paths are relative to the file being checked."
 (flycheck-define-checker erlang
   "An Erlang syntax checker using the Erlang interpreter.
 
-See URL `http://www.erlang.org/'."
+See URL `https://www.erlang.org/'."
   :command ("erlc"
             "-o" temporary-directory
             (option-list "-I" flycheck-erlang-include-path)
@@ -9001,7 +9079,7 @@ directory name is \"test\" or \"eqc\", or else \"default\"."
 (flycheck-define-checker eruby-erubis
   "An eRuby syntax checker using the `erubis' command.
 
-See URL `http://www.kuwata-lab.com/erubis/'."
+See URL `https://www.kuwata-lab.com/erubis/'."
   :command ("erubis" "-z" source)
   :error-patterns
   ((error line-start (file-name) ":" line ": " (message) line-end))
@@ -9151,6 +9229,18 @@ Uses GCC's Fortran compiler gfortran.  See URL
             "Warning: " (message) line-end))
   :modes (fortran-mode f90-mode))
 
+(flycheck-define-checker yaml-actionlint
+  "A YAML syntax checker using actionlint.
+
+See URL https://github.com/rhysd/actionlint/."
+  :command ("actionlint" "-oneline" source)
+  :error-patterns ((error line-start (file-name) ":" line ":" column ": " (message) line-end))
+  :modes (yaml-mode yaml-ts-mode)
+  :predicate (lambda ()
+               (string-match-p
+                (rx (or ".github/workflows" ".github\\workflows"))
+                (buffer-file-name))))
+
 (flycheck-define-checker go-gofmt
   "A Go syntax and style checker using the gofmt utility.
 
@@ -9161,27 +9251,13 @@ See URL `https://golang.org/cmd/gofmt/'."
   ((error line-start "<standard input>:" line ":" column ": "
           (message) line-end))
   :modes (go-mode go-ts-mode)
-  :next-checkers ((warning . go-golint)
-                  ;; Fall back, if go-golint doesn't exist
-                  (warning . go-vet)
+  :next-checkers ((warning . go-vet)
                   ;; Fall back, if go-vet doesn't exist
                   (warning . go-build) (warning . go-test)
                   (warning . go-errcheck)
                   (warning . go-unconvert)
                   (warning . go-staticcheck)))
 
-(flycheck-define-checker go-golint
-  "A Go style checker using Golint.
-
-See URL `https://github.com/golang/lint'."
-  :command ("golint" source)
-  :error-patterns
-  ((warning line-start (file-name) ":" line ":" column ": " (message) line-end))
-  :modes (go-mode go-ts-mode)
-  :next-checkers (go-vet
-                  ;; Fall back, if go-vet doesn't exist
-                  go-build go-test go-errcheck go-unconvert))
-
 (flycheck-def-option-var flycheck-go-vet-print-functions nil go-vet
   "A list of print-like functions for `go vet'.
 
@@ -9338,7 +9414,7 @@ See URL `https://github.com/kisielk/errcheck'."
   (lambda (errors)
     (let ((errors (flycheck-sanitize-errors errors)))
       (dolist (err errors)
-        (-when-let (message (flycheck-error-message err))
+        (when-let (message (flycheck-error-message err))
           ;; Improve the messages reported by errcheck to make them more clear.
           (setf (flycheck-error-message err)
                 (format "Ignored `error` returned from `%s`" message)))))
@@ -9376,7 +9452,7 @@ limited features) if `flycheck-go-version' is set. See URL
 (flycheck-define-checker groovy
   "A groovy syntax checker using groovy compiler API.
 
-See URL `http://www.groovy-lang.org'."
+See URL `https://www.groovy-lang.org'."
   :command ("groovy" "-e"
             "import org.codehaus.groovy.control.*
 
@@ -9397,7 +9473,7 @@ try {
 (flycheck-define-checker haml
   "A Haml syntax checker using the Haml compiler.
 
-See URL `http://haml.info'."
+See URL `https://haml.info'."
   :command ("haml" "-c" "--stdin")
   :standard-input t
   :error-patterns
@@ -9405,10 +9481,20 @@ See URL `http://haml.info'."
    (error line-start ":" line ": syntax error, " (message) line-end))
   :modes haml-mode)
 
+(flycheck-define-checker haml-lint
+  "HAML-Lint style checker.
+
+See URL `https://github.com/sds/haml-lint'."
+  :command ("haml-lint" "--no-color" "--no-summary" source)
+  :error-patterns
+  ((error line-start (file-name) ":" line " [E]" (message) line-end)
+   (warning line-start (file-name) ":" line " [W]" (message) line-end))
+  :modes haml-mode)
+
 (flycheck-define-checker handlebars
   "A Handlebars syntax checker using the Handlebars compiler.
 
-See URL `http://handlebarsjs.com/'."
+See URL `https://handlebarsjs.com/'."
   :command ("handlebars" "-i-")
   :standard-input t
   :error-patterns
@@ -9530,12 +9616,12 @@ directory returned by \"stack path --project-root\"."
      (flycheck--locate-dominating-file-matching
       (file-name-directory (buffer-file-name))
       (rx "stack" (* any) "." (or "yml" "yaml") eos)))
-   (-when-let* ((stack (funcall flycheck-executable-find "stack"))
-                (output (ignore-errors
-                          (process-lines stack
-                                         "--no-install-ghc"
-                                         "path" "--project-root")))
-                (stack-dir (car output)))
+   (when-let* ((stack (funcall flycheck-executable-find "stack"))
+               (output (ignore-errors
+                         (process-lines stack
+                                        "--no-install-ghc"
+                                        "path" "--project-root")))
+               (stack-dir (car output)))
      (and (file-directory-p stack-dir) stack-dir))))
 
 (defun flycheck-haskell--ghc-find-default-directory (_checker)
@@ -9579,6 +9665,7 @@ See URL `https://github.com/commercialhaskell/stack'."
                            (one-or-more (not (any ?\n ?|)))))
             line-end)
    (error line-start (file-name) ":" line ":" column ":" (optional " error:")
+          (optional " " "[" (id (one-or-more not-newline)) "]")
           (or (message (one-or-more not-newline))
               (and "\n"
                    (message
@@ -9638,6 +9725,7 @@ See URL `https://www.haskell.org/ghc/'."
                            (one-or-more (not (any ?\n ?|)))))
             line-end)
    (error line-start (file-name) ":" line ":" column ":" (optional " error:")
+          (optional " " "[" (id (one-or-more not-newline)) "]")
           (or (message (one-or-more not-newline))
               (and "\n"
                    (message
@@ -9653,7 +9741,7 @@ See URL `https://www.haskell.org/ghc/'."
   :next-checkers ((warning . haskell-hlint))
   :working-directory flycheck-haskell--ghc-find-default-directory)
 
-(flycheck-def-config-file-var flycheck-hlintrc haskell-hlint "HLint.hs")
+(flycheck-def-config-file-var flycheck-hlintrc haskell-hlint ".hlint.yaml")
 
 (flycheck-def-args-var flycheck-hlint-args haskell-hlint
   :package-version '(flycheck . "0.25"))
@@ -9695,6 +9783,7 @@ string is a default hint package (e.g. (\"Generalise\"
 
 See URL `https://github.com/ndmitchell/hlint'."
   :command ("hlint"
+            "--no-exit-code"
             (option-list "-X" flycheck-hlint-language-extensions concat)
             (option-list "-i=" flycheck-hlint-ignore-rules concat)
             (option-list "-h" flycheck-hlint-hint-packages concat)
@@ -9757,7 +9846,7 @@ extract Javascript if a HTML file is detected.  If `always' or
 `never' extract Javascript always or never respectively.
 
 Refer to the jshint manual at the URL
-`http://jshint.com/docs/cli/#flags' for more information."
+`https://jshint.com/docs/cli/#flags' for more information."
   :type
   '(choice (const :tag "No extraction rule" nil)
            (const :tag "Try to extract Javascript when detecting HTML files"
@@ -9770,7 +9859,7 @@ Refer to the jshint manual at the URL
 (flycheck-define-checker javascript-jshint
   "A Javascript syntax and style checker using jshint.
 
-See URL `http://www.jshint.com'."
+See URL `https://www.jshint.com'."
   :command ("jshint" "--reporter=checkstyle"
             "--filename" source-original
             (config-file "--config" flycheck-jshintrc)
@@ -9795,7 +9884,7 @@ The value of this variable is a list of strings, where each
 string is a directory with custom rules for ESLint.
 
 Refer to the ESLint manual at URL
-`http://eslint.org/docs/user-guide/command-line-interface#--rulesdir'
+`https://eslint.org/docs/user-guide/command-line-interface#--rulesdir'
 for more information about the custom directories."
   :type '(repeat (directory :tag "Custom rules directory"))
   :safe #'flycheck-string-list-p
@@ -9983,7 +10072,7 @@ See URL `https://jsonnet.org'."
 
 Requires lessc 1.4 or newer.
 
-See URL `http://lesscss.org'."
+See URL `https://lesscss.org'."
   :command ("lessc" "--lint" "--no-color"
             "-")
   :standard-input t
@@ -9998,13 +10087,13 @@ See URL `http://lesscss.org'."
 (flycheck-define-checker less-stylelint
   "A LESS syntax and style checker using stylelint.
 
-See URL `http://stylelint.io/'."
+See URL `https://stylelint.io/'."
   :command ("stylelint"
             (eval flycheck-stylelint-args)
-            "--syntax" "less"
             (option-flag "--quiet" flycheck-stylelint-quiet)
             (config-file "--config" flycheck-stylelintrc))
   :standard-input t
+  :verify (lambda (_) (flycheck--stylelint-verify 'less-stylelint))
   :error-parser flycheck-parse-stylelint
   :predicate flycheck-buffer-nonempty-p
   :modes (less-css-mode))
@@ -10012,7 +10101,7 @@ See URL `http://stylelint.io/'."
 (flycheck-define-checker llvm-llc
   "Flycheck LLVM IR checker using llc.
 
-See URL `http://llvm.org/docs/CommandGuide/llc.html'."
+See URL `https://llvm.org/docs/CommandGuide/llc.html'."
   :command ("llc" "-o" null-device source)
   :error-patterns
   ((error line-start
@@ -10068,12 +10157,12 @@ See URL `https://github.com/mpeterv/luacheck'."
           ;; the ID is optional here
           (optional " (" (id "E" (one-or-more digit)) ") ")
           (message) line-end))
-  :modes lua-mode)
+  :modes (lua-mode lua-ts-mode))
 
 (flycheck-define-checker lua
   "A Lua syntax checker using the Lua compiler.
 
-See URL `http://www.lua.org/'."
+See URL `https://www.lua.org/'."
   :command ("luac" "-p" "-")
   :standard-input t
   :error-patterns
@@ -10081,7 +10170,7 @@ See URL `http://www.lua.org/'."
           ;; Skip the name of the luac executable.
           (minimal-match (zero-or-more not-newline))
           ": stdin:" line ": " (message) line-end))
-  :modes lua-mode)
+  :modes (lua-mode lua-ts-mode))
 
 (flycheck-define-checker opam
   "A Opam syntax and style checker using opam lint.
@@ -10196,18 +10285,67 @@ See URL `https://metacpan.org/pod/Perl::Critic'."
           "STDIN/" line "/" column "/" (any "5") "/"
           (id (one-or-more (not (any "/")))) "/" (message)
           line-end))
+  :modes (cperl-mode perl-mode)
+  :next-checkers (perl-perlimports)
+
+  :error-explainer
+  (lambda (err)
+    (let ((error-code (flycheck-error-id err))
+          (url "https://metacpan.org/pod/Perl::Critic::Policy::%s"))
+      (and error-code `(url . ,(format url error-code))))))
+
+(defun flycheck-perl-perlimports-parse-errors (output checker buffer)
+  "Parse perlimports json output errors from OUTPUT.
+
+CHECKER and BUFFER denoted the CHECKER that returned OUTPUT and
+the BUFFER that was checked respectively.
+
+See URL `https://metacpan.org/dist/App-perlimports/view/script/perlimports'
+for more information about perlimports."
+  (mapcar (lambda (err)
+            (let-alist err
+              (flycheck-error-new-at
+               .location.start.line
+               .location.start.column
+               'info
+               (concat .module " " .reason ":"
+                       (with-temp-buffer
+                         (insert (substring .diff (string-match-p "\n" .diff)))
+                         (diff-mode)
+                         (font-lock-ensure)
+                         (buffer-string)))
+               :end-line .location.end.line
+               :end-column .location.end.column
+               :checker checker
+               :buffer buffer)))
+          (flycheck-parse-json output)))
+
+(flycheck-define-checker perl-perlimports
+  "A checker for cleaning up Perl import statements.
+
+See URL `https://metacpan.org/dist/App-perlimports/view/script/perlimports'."
+  :command ("perlimports"
+            "--filename" source
+            "--json"
+            "--lint"
+            "--no-preserve-duplicates"
+            "--no-preserve-unused"
+            "--no-tidy-whitespace"
+            "--read-stdin")
+  :standard-input t
+  :error-parser flycheck-perl-perlimports-parse-errors
   :modes (cperl-mode perl-mode))
 
 (flycheck-define-checker php
   "A PHP syntax checker using the PHP command line interpreter.
 
-See URL `http://php.net/manual/en/features.commandline.php'."
+See URL `https://php.net/manual/en/features.commandline.php'."
   :command ("php" "-l" "-d" "error_reporting=E_ALL" "-d" "display_errors=1"
             "-d" "log_errors=0" source)
   :error-patterns
   ((error line-start (or "Parse" "Fatal" "syntax") " error" (any ":" ",") " "
           (message) " in " (file-name) " on line " line line-end))
-  :modes (php-mode php+-mode)
+  :modes (php-mode php-ts-mode php+-mode)
   :next-checkers ((warning . php-phpmd)
                   (warning . php-phpcs)))
 
@@ -10232,7 +10370,7 @@ See URL `https://phpmd.org/'."
             (eval (flycheck-option-comma-separated-list
                    flycheck-phpmd-rulesets)))
   :error-parser flycheck-parse-phpmd
-  :modes (php-mode php+-mode)
+  :modes (php-mode php-ts-mode php+-mode)
   :next-checkers (php-phpcs))
 
 (flycheck-def-option-var flycheck-phpcs-standard nil php-phpcs
@@ -10251,7 +10389,7 @@ or as path to a standard specification."
 
 Needs PHP Code Sniffer 2.6 or newer.
 
-See URL `http://pear.php.net/package/PHP_CodeSniffer/'."
+See URL `https://pear.php.net/package/PHP_CodeSniffer/'."
   :command ("phpcs" "--report=checkstyle"
             ;; Use -q flag to force quiet mode
             ;; Quiet mode prevents errors from extra output when phpcs has
@@ -10261,8 +10399,8 @@ See URL `http://pear.php.net/package/PHP_CodeSniffer/'."
             ;; Some files are not detected correctly
             ;; so it is necessary to pass the extension.
             (eval
-             (-when-let* ((fname buffer-file-name)
-                          (ext (file-name-extension fname)))
+             (when-let* ((fname buffer-file-name)
+                         (ext (file-name-extension fname)))
                (concat "--extensions=" ext)))
 
             ;; Pass original file name to phpcs.  We need to concat explicitly
@@ -10275,6 +10413,28 @@ See URL `http://pear.php.net/package/PHP_CodeSniffer/'."
   :standard-input t
   :error-parser flycheck-parse-checkstyle
   :error-filter
+  (lambda (errors)
+    (flycheck-sanitize-errors
+     (flycheck-remove-error-file-names "STDIN" errors)))
+  :modes (php-mode php-ts-mode php+-mode)
+  ;; phpcs seems to choke on empty standard input, hence skip phpcs if the
+  ;; buffer is empty, see https://github.com/flycheck/flycheck/issues/907
+  :predicate flycheck-buffer-nonempty-p)
+
+(flycheck-define-checker php-phpcs-changed
+  "A PHP style checker using PHPCS-Changed.
+   Needs PHP Code Sniffer 2.6 or newer.
+   See `https://github.com/sirbrillig/phpcs-changed'."
+  :command ("phpcs-changed"
+            "--git"
+            "--git-base trunk"
+            "--git-unstaged"
+            (option "--standard=" flycheck-phpcs-standard concat)
+            (eval (buffer-file-name))
+            )
+  :standard-input t
+  :error-parser flycheck-parse-checkstyle
+  :error-filter
   (lambda (errors)
     (flycheck-sanitize-errors
      (flycheck-remove-error-file-names "STDIN" errors)))
@@ -10306,7 +10466,7 @@ See https://github.com/processing/processing/wiki/Command-Line"
 CHECKER and BUFFER denoted the CHECKER that returned OUTPUT and
 the BUFFER that was checked respectively.
 
-See URL `http://proselint.com/' for more information about proselint."
+See URL `https://proselint.com/' for more information about proselint."
   (mapcar (lambda (err)
             (let-alist err
               (flycheck-error-new-at-pos
@@ -10329,7 +10489,7 @@ See URL `http://proselint.com/' for more information about proselint."
 (flycheck-define-checker proselint
   "Flycheck checker using Proselint.
 
-See URL `http://proselint.com/'."
+See URL `https://proselint.com/'."
   :command ("proselint" "--json" "-")
   :standard-input t
   :error-parser flycheck-proselint-parse-errors
@@ -10443,7 +10603,7 @@ See URL `https://puppet.com/'."
           ": Could not parse for environment " (one-or-more word)
           ": " (message (minimal-match (zero-or-more anything)))
           " at " (file-name "/" (zero-or-more not-newline)) ":" line line-end))
-  :modes puppet-mode
+  :modes (puppet-mode puppet-ts-mode)
   :next-checkers ((warning . puppet-lint)))
 
 (flycheck-def-config-file-var flycheck-puppet-lint-rc puppet-lint
@@ -10457,7 +10617,7 @@ The value of this variable is a list of strings, where each
 string is the name of a check to disable (e.g. \"80chars\" or
 \"double_quoted_strings\").
 
-See URL `http://puppet-lint.com/checks/' for a list of all checks
+See URL `https://puppet-lint.com/checks/' for a list of all checks
 and their names."
   :type '(repeat (string :tag "Check Name"))
   :package-version '(flycheck . "26"))
@@ -10469,7 +10629,7 @@ and their names."
 (flycheck-define-checker puppet-lint
   "A Puppet DSL style checker using puppet-lint.
 
-See URL `http://puppet-lint.com/'."
+See URL `https://puppet-lint.com/'."
   ;; We must check the original file, because Puppetlint is quite picky on the
   ;; names of files and there place in the directory structure, to comply with
   ;; Puppet's autoload directory layout.  For instance, a class foo::bar is
@@ -10485,7 +10645,7 @@ See URL `http://puppet-lint.com/'."
   :error-patterns
   ((warning line-start (file-name) ":" line ":warning: " (message) line-end)
    (error line-start (file-name) ":" line ":error: " (message) line-end))
-  :modes puppet-mode
+  :modes (puppet-mode puppet-ts-mode)
   ;; Since we check the original file, we can only use this syntax checker if
   ;; the buffer is actually linked to a file, and if it is not modified.
   :predicate flycheck-buffer-saved-p)
@@ -10494,8 +10654,8 @@ See URL `http://puppet-lint.com/'."
   "Run a python SNIPPET and return the output.
 
 CHECKER's executable is assumed to be a Python REPL."
-  (-when-let (output (flycheck-call-checker-process-for-output
-                      checker nil nil "-c" snippet))
+  (when-let (output (flycheck-call-checker-process-for-output
+                     checker nil nil "-c" snippet))
     (string-trim output)))
 
 (defun flycheck-python-get-path (checker)
@@ -10554,7 +10714,7 @@ current project; `.pylintrc' is not part of the list because it
 is commonly found in ~/."
   :group 'flycheck
   :type '(repeat (string :tag "File name"))
-  :package-version '(flycheck . "0.33")
+  :package-version '(flycheck . "33")
   :safe #'flycheck-string-list-p)
 
 (defun flycheck-python-find-project-root (_checker)
@@ -10688,6 +10848,41 @@ Requires Flake8 3.0 or newer. See URL
   :next-checkers ((warning . python-pylint)
                   (warning . python-mypy)))
 
+(flycheck-def-config-file-var flycheck-python-ruff-config python-ruff
+                              '("pyproject.toml" "ruff.toml" ".ruff.toml"))
+
+(flycheck-define-checker python-ruff
+  "A Python syntax and style checker using Ruff.
+
+See URL `https://docs.astral.sh/ruff/'."
+  :command ("ruff"
+            "check"
+            (config-file "--config" flycheck-python-ruff-config)
+            "--output-format=concise"
+            (option "--stdin-filename" buffer-file-name)
+            "-")
+  :standard-input t
+  :error-filter (lambda (errors)
+                  (let* ((errors (flycheck-sanitize-errors errors))
+                         (errors-with-ids (seq-filter #'flycheck-error-id errors)))
+                    (seq-union
+                     (seq-difference errors errors-with-ids)
+                     (seq-map #'flycheck-flake8-fix-error-level errors-with-ids))))
+  :error-patterns
+  ((error line-start
+          (or "-" (file-name)) ":" line ":" (optional column ":") " "
+          "SyntaxError: "
+          (message (one-or-more not-newline))
+          line-end)
+   (warning line-start
+            (or "-" (file-name)) ":" line ":" (optional column ":") " "
+            (id (one-or-more (any alpha)) (one-or-more digit) " ")
+            (message (one-or-more not-newline))
+            line-end))
+  :working-directory flycheck-python-find-project-root 
+  :modes (python-mode python-ts-mode)
+  :next-checkers ((warning . python-mypy)))
+
 (flycheck-def-config-file-var
     flycheck-pylintrc python-pylint
     '("pylintrc" ".pylintrc" "pyproject.toml" "setup.cfg"))
@@ -10749,7 +10944,7 @@ See URL `https://www.pylint.org/'."
                  (flycheck-python-find-module 'python-pylint "pylint")))
   :verify (lambda (_) (flycheck-python-verify-module 'python-pylint "pylint"))
   :error-explainer (lambda (err)
-                     (-when-let (id (flycheck-error-id err))
+                     (when-let (id (flycheck-error-id err))
                        (apply
                         #'flycheck-call-checker-process-for-output
                         'python-pylint nil t
@@ -10838,7 +11033,7 @@ See URL https://github.com/microsoft/pyright."
 (flycheck-define-checker python-mypy
   "Mypy syntax and type checker.  Requires mypy>=0.730.
 
-See URL `http://mypy-lang.org/'."
+See URL `https://mypy-lang.org/'."
   :command ("mypy"
             "--show-column-numbers"
             "--no-pretty"
@@ -10919,6 +11114,21 @@ See URL `https://github.com/jimhester/lintr'."
                 :message (if has-lintr "present" "missing")
                 :face (if has-lintr 'success '(bold error)))))))
 
+(flycheck-define-checker r
+  "An R syntax checker using the builtin `parse' function.
+
+See URL: `https://www.r-project.org/'."
+  :command ("R" "--slave" "--no-restore" "--no-save" "-e"
+            "parse(file=file('stdin'), srcfile='<stdin>')")
+  :standard-input t
+  :error-patterns
+  ((error line-start (zero-or-more space) "<stdin>:" line ":" column ": "
+          (message) line-end))
+  :modes (ess-mode ess-r-mode)
+  :predicate
+  ;; Don't check ESS files which do not contain R
+  (lambda () (equal ess-language "S")))
+
 (defun flycheck-racket-has-expand-p (checker)
   "Whether the executable of CHECKER provides the `expand' command."
   (eql 0 (flycheck-call-checker-process checker nil nil nil "expand")))
@@ -10999,10 +11209,10 @@ See URL `https://github.com/rpm-software-management/rpmlint'."
     errors)
   :error-explainer
   (lambda (error)
-    (-when-let* ((error-message (flycheck-error-message error))
-                 (message-id (save-match-data
-                               (string-match "\\([^ ]+\\)" error-message)
-                               (match-string 1 error-message))))
+    (when-let* ((error-message (flycheck-error-message error))
+                (message-id (save-match-data
+                              (string-match "\\([^ ]+\\)" error-message)
+                              (match-string 1 error-message))))
       (flycheck-call-checker-process-for-output
        'rpm-rpmlint nil t "-I" message-id)))
   :modes (sh-mode rpm-spec-mode)
@@ -11034,7 +11244,7 @@ See URL `https://github.com/rpm-software-management/rpmlint'."
 (flycheck-define-checker markdown-markdownlint-cli
   "Markdown checker using markdownlint-cli.
 
-See URL `https://github.com/DavidAnson/markdownlint-cli'."
+See URL `https://github.com/igorshubovych/markdownlint-cli'."
   :command ("markdownlint"
             (config-file "--config" flycheck-markdown-markdownlint-cli-config)
             (option-list "--disable" flycheck-markdown-markdownlint-cli-disable-rules)
@@ -11050,7 +11260,12 @@ See URL `https://github.com/DavidAnson/markdownlint-cli'."
   (lambda (errors)
     (flycheck-sanitize-errors
      (flycheck-remove-error-file-names "(string)" errors)))
-  :modes (markdown-mode gfm-mode))
+  :modes (markdown-mode gfm-mode)
+  :error-explainer
+  (lambda (err)
+    (let ((error-code (substring (flycheck-error-id err) 0 5))
+          (url "https://github.com/DavidAnson/markdownlint/blob/main/doc/Rules.md#%s"))
+      (and error-code `(url . ,(format url error-code))))))
 
 (flycheck-def-option-var flycheck-markdown-mdl-rules nil markdown-mdl
   "Rules to enable for mdl.
@@ -11104,6 +11319,29 @@ See URL `https://github.com/markdownlint/markdownlint'."
      (flycheck-remove-error-file-names "(stdin)" errors)))
   :modes (markdown-mode gfm-mode))
 
+(flycheck-def-config-file-var flycheck-markdown-pymarkdown-config
+    markdown-pymarkdown nil
+  :package-version '(flycheck . "34"))
+
+(flycheck-define-checker markdown-pymarkdown
+  "Markdown checker using PyMarkdown.
+
+See URL `https://pypi.org/project/pymarkdownlnt/'."
+  :command ("pymarkdown"
+            (config-file "--config" flycheck-markdown-markdownlint-cli-config)
+            "scan"
+            source)
+  :error-patterns
+  ((error line-start
+          (file-name) ":" line
+          (? ":" column) ": " (id (one-or-more alnum))
+          ": " (message) line-end))
+  :error-filter
+  (lambda (errors)
+    (flycheck-sanitize-errors
+     (flycheck-remove-error-file-names "(string)" errors)))
+  :modes (markdown-mode gfm-mode))
+
 (flycheck-define-checker nix
   "Nix checker using nix-instantiate.
 
@@ -11127,7 +11365,7 @@ See URL `https://nixos.org/nix/manual/#sec-nix-instantiate'."
     (flycheck-sanitize-errors
      (flycheck-remove-error-file-names "(string)" errors)))
   :next-checkers ((warning . nix-linter))
-  :modes nix-mode)
+  :modes (nix-mode nix-ts-mode))
 
 (defun flycheck-parse-nix-linter (output checker buffer)
   "Parse nix-linter warnings from JSON OUTPUT.
@@ -11161,9 +11399,53 @@ See URL `https://github.com/Synthetica9/nix-linter'."
   :error-parser flycheck-parse-nix-linter
   :error-explainer
   (lambda (error)
-    (-when-let (error-code (flycheck-error-id error))
+    (when-let (error-code (flycheck-error-id error))
       (flycheck-call-checker-process-for-output
        'nix-linter nil t "--help-for" error-code)))
+  :modes (nix-mode nix-ts-mode))
+
+(defun flycheck-parse-statix (output checker buffer)
+  "Parse statix warnings from JSON OUTPUT.
+
+CHECKER and BUFFER denote the CHECKER that returned OUTPUT and
+the BUFFER that was checked respectively.
+
+See URL `https://github.com/nerdypepper/statix' for more
+information about statix."
+  (mapcar (lambda (err)
+            ;; Diagnostic information is a (seemingly always) 1 element array.
+            (let-alist (car (alist-get 'diagnostics err))
+              (let ((message .message)
+                    (start-line .at.from.line)
+                    (start-column .at.from.column)
+                    (end-line .at.to.line)
+                    (end-column .at.to.column))
+
+                (let-alist err
+                  (flycheck-error-new-at
+                   start-line
+                   start-column
+                   (pcase .severity ("Error" 'error)
+                          ("Warn" 'warning)
+                          (_ 'warning))
+                   (format "%s: %s" .note message)
+                   :id (format "%s%02d" (pcase .severity
+                                          ("Error" "E")
+                                          ("Warn" "W")
+                                          (_ "")) .code)
+                   :checker checker
+                   :buffer buffer
+                   :filename (buffer-file-name buffer)
+                   :end-line end-line
+                   :end-column end-column)))))
+          (alist-get 'report (car (flycheck-parse-json output)))))
+
+(flycheck-define-checker statix
+  "Nix checker using statix.
+
+See URL `https://github.com/nerdypepper/statix'."
+  :command ("statix" "check" "-o=json" source)
+  :error-parser flycheck-parse-statix
   :modes nix-mode)
 
 (defun flycheck-locate-sphinx-source-directory ()
@@ -11171,14 +11453,14 @@ See URL `https://github.com/Synthetica9/nix-linter'."
 
 Return the source directory, or nil, if the current buffer is not
 part of a Sphinx project."
-  (-when-let* ((filename (buffer-file-name))
-               (dir (locate-dominating-file filename "conf.py")))
+  (when-let* ((filename (buffer-file-name))
+              (dir (locate-dominating-file filename "conf.py")))
     (expand-file-name dir)))
 
 (flycheck-define-checker rst
   "A ReStructuredText (RST) syntax checker using Docutils.
 
-See URL `http://docutils.sourceforge.net/'."
+See URL `https://docutils.sourceforge.net/'."
   ;; include:: directives
   :command ("rst2pseudoxml.py" "--report=2" "--halt=5"
             ;; Read from standard input and throw output away
@@ -11203,7 +11485,7 @@ Sphinx via `-n'."
 (flycheck-define-checker rst-sphinx
   "A ReStructuredText (RST) syntax checker using Sphinx.
 
-Requires Sphinx 1.2 or newer.  See URL `http://sphinx-doc.org'."
+Requires Sphinx 1.2 or newer.  See URL `https://sphinx-doc.org'."
   :command ("sphinx-build" "-b" "pseudoxml"
             "-q" "-N"                   ; Reduced output and no colors
             (option-flag "-n" flycheck-sphinx-warn-on-missing-references)
@@ -11229,11 +11511,17 @@ This is either a parent directory containing a Gemfile, or nil."
    buffer-file-name
    (locate-dominating-file buffer-file-name "Gemfile")))
 
+(defun flycheck-ruby--filter-rubocop-errors (errors)
+  "Filter RuboCop ERRORS attributed to dummy stdin filename."
+  (flycheck-remove-error-file-names
+   (flycheck--file-truename (expand-file-name "stdin"))
+   errors))
+
 (flycheck-def-config-file-var flycheck-rubocoprc ruby-rubocop ".rubocop.yml")
 
 (flycheck-def-option-var flycheck-rubocop-lint-only nil
-                         (ruby-rubocop ruby-standard)
-  "Whether to only report code issues in Rubocop and Standard.
+                         (ruby-rubocop ruby-standard ruby-chef-cookstyle)
+  "Whether to only report code issues in Rubocop, Cookstyle and Standard.
 
 When non-nil, only report code issues, via `--lint'.  Otherwise
 report style issues as well."
@@ -11263,23 +11551,57 @@ See URL `https://rubocop.org/'."
              "--display-cop-names"
              "--force-exclusion"
              "--format" "emacs"
-             ;; Explicitly disable caching to prevent Rubocop 0.35.1 and earlier
-             ;; from caching standard input.  Later versions of Rubocop
-             ;; automatically disable caching with --stdin, see
-             ;; https://github.com/flycheck/flycheck/issues/844 and
-             ;; https://github.com/bbatsov/rubocop/issues/2576
-             "--cache" "false"
              (config-file "--config" flycheck-rubocoprc)
              (option-flag "--lint" flycheck-rubocop-lint-only)
-             ;; Rubocop takes the original file name as argument when reading
-             ;; from standard input
-             "--stdin" source-original)
+             ;; RuboCop takes the original file name as argument when reading
+             ;; from standard input, but it chokes when that name is the empty
+             ;; string, so fall back to "stdin" in order to handle buffers with
+             ;; no backing file (e.g. org-mode snippet buffers)
+             "--stdin" (eval (or (buffer-file-name) "stdin")))
   :standard-input t
   :working-directory #'flycheck-ruby--find-project-root
   :error-patterns flycheck-ruby-rubocop-error-patterns
+  :error-filter #'flycheck-ruby--filter-rubocop-errors
   :modes '(enh-ruby-mode ruby-mode ruby-ts-mode)
   :next-checkers '((warning . ruby-reek)
-                   (warning . ruby-rubylint)))
+                   (warning . ruby-chef-cookstyle)))
+
+(flycheck-def-executable-var ruby-chef-cookstyle "cookstyle")
+(flycheck-define-command-checker 'ruby-chef-cookstyle
+  "A Chef (Ruby) syntax and style checker using the Cookstyle tool.
+Basically Cookstyle is a thin wrapper around RuboCop, so this
+checker is essentially the same.
+
+See URL `https://github.com/chef/cookstyle'."
+  :command '("cookstyle"
+             "--display-cop-names"
+             "--force-exclusion"
+             "--format" "emacs"
+             (config-file "--config" flycheck-rubocoprc)
+             (option-flag "--lint" flycheck-rubocop-lint-only)
+             ;; RuboCop takes the original file name as argument when reading
+             ;; from standard input, but it chokes when that name is the empty
+             ;; string, so fall back to "stdin" in order to handle buffers with
+             ;; no backing file (e.g. org-mode snippet buffers)
+             "--stdin" (eval (or (buffer-file-name) "stdin")))
+  :standard-input t
+  :working-directory #'flycheck-ruby--find-project-root
+  :error-patterns flycheck-ruby-rubocop-error-patterns
+  :error-filter #'flycheck-ruby--filter-rubocop-errors
+  :modes '(enh-ruby-mode ruby-mode ruby-ts-mode)
+  :predicate
+  (lambda ()
+    (let ((parent-dir (file-name-directory
+                       (directory-file-name
+                        (expand-file-name default-directory)))))
+      (or
+       ;; Chef CookBook
+       ;; https://docs.opscode.com/chef/knife.html#id38
+       (locate-dominating-file parent-dir "recipes")
+       ;; Knife Solo
+       ;; https://matschaffer.github.io/knife-solo/#label-Init+command
+       (locate-dominating-file parent-dir "cookbooks"))))
+  :next-checkers '((warning . ruby-reek)))
 
 (flycheck-def-config-file-var flycheck-ruby-standardrc ruby-standard
                               ".standard.yml")
@@ -11301,9 +11623,10 @@ See URL `https://github.com/testdouble/standard' for more information."
   :standard-input t
   :working-directory #'flycheck-ruby--find-project-root
   :error-patterns flycheck-ruby-rubocop-error-patterns
+  :error-filter #'flycheck-ruby--filter-rubocop-errors
   :modes '(enh-ruby-mode ruby-mode ruby-ts-mode)
   :next-checkers '((warning . ruby-reek)
-                   (warning . ruby-rubylint)))
+                   (warning . ruby-chef-cookstyle)))
 
 (flycheck-def-config-file-var flycheck-reekrc ruby-reek ".reek.yml"
   :safe #'string-or-null-p
@@ -11317,29 +11640,6 @@ See URL `https://github.com/troessner/reek'."
             (config-file "--config" flycheck-reekrc)
             source)
   :error-parser flycheck-parse-reek
-  :modes (enh-ruby-mode ruby-mode ruby-ts-mode)
-  :next-checkers ((warning . ruby-rubylint)))
-
-;; Default to `nil' to let Rubylint find its configuration file by itself, and
-;; to maintain backwards compatibility with older Rubylint and Flycheck releases
-(flycheck-def-config-file-var flycheck-rubylintrc ruby-rubylint nil)
-
-(flycheck-define-checker ruby-rubylint
-  "A Ruby syntax and code analysis checker using ruby-lint.
-
-Requires ruby-lint 2.0.2 or newer.  See URL
-`https://github.com/YorickPeterse/ruby-lint'."
-  :command ("ruby-lint" "--presenter=syntastic"
-            (config-file "--config" flycheck-rubylintrc)
-            source)
-  ;; Ruby Lint can't read from standard input
-  :error-patterns
-  ((info line-start
-         (file-name) ":I:" line ":" column ": " (message) line-end)
-   (warning line-start
-            (file-name) ":W:" line ":" column ": " (message) line-end)
-   (error line-start
-          (file-name) ":E:" line ":" column ": " (message) line-end))
   :modes (enh-ruby-mode ruby-mode ruby-ts-mode))
 
 (flycheck-define-checker ruby
@@ -11363,7 +11663,7 @@ See URL `https://www.ruby-lang.org/'."
             " warning: " (message) line-end)
    (error line-start "-:" line ": " (message) line-end))
   :modes (enh-ruby-mode ruby-mode ruby-ts-mode)
-  :next-checkers ((warning . ruby-rubylint)))
+  :next-checkers ((warning . ruby-chef-cookstyle)))
 
 (flycheck-define-checker ruby-jruby
   "A Ruby syntax checker using the JRuby interpreter.
@@ -11371,17 +11671,16 @@ See URL `https://www.ruby-lang.org/'."
 This syntax checker is very primitive, and may break on future
 versions of JRuby.
 
-Please consider using `ruby-rubocop' or `ruby-rubylint' instead.
+Please consider using `ruby-rubocop' instead.
 
-See URL `http://jruby.org/'."
+See URL `https://jruby.org/'."
   :command ("jruby" "-w" "-c")
   :standard-input t
   :error-patterns
   ((error   line-start "SyntaxError in -:" line ": " (message) line-end)
    (warning line-start "-:" line ": warning: " (message) line-end)
    (error   line-start "-:" line ": "          (message) line-end))
-  :modes (enh-ruby-mode ruby-mode ruby-ts-mode)
-  :next-checkers ((warning . ruby-rubylint)))
+  :modes (enh-ruby-mode ruby-mode ruby-ts-mode))
 
 (flycheck-def-args-var flycheck-cargo-check-args (rust-cargo)
   :package-version '(flycheck . "32"))
@@ -11497,7 +11796,7 @@ Relative paths are relative to the file being checked."
 
 (defun flycheck-rust-error-explainer (error)
   "Return an explanation for the given `flycheck-error' ERROR."
-  (-when-let (error-code (flycheck-error-id error))
+  (when-let (error-code (flycheck-error-id error))
     (lambda ()
       (flycheck-call-checker-process
        'rust nil standard-output t "--explain" error-code)
@@ -11511,10 +11810,10 @@ Relative paths are relative to the file being checked."
      (or
       ;; Macro errors emit a diagnostic in a phony file,
       ;; e.g. "<println macros>".
-      (-when-let (filename (flycheck-error-filename err))
+      (when-let (filename (flycheck-error-filename err))
         (string-match-p (rx "macros>" line-end) filename))
       ;; Redundant message giving the number of failed errors
-      (-when-let (msg (flycheck-error-message err))
+      (when-let (msg (flycheck-error-message err))
         (string-match-p
          (rx
           (or (: "aborting due to " (optional (one-or-more num) " ")
@@ -11555,9 +11854,9 @@ versions inferior to 1.25)."
 Execute `cargo --list' to find out whether COMMAND is present."
   (let ((cargo (funcall flycheck-executable-find "cargo")))
     (member command
-      (mapcar (lambda (line)
-                (replace-regexp-in-string "\\s-*\\(\\S-+\\).*\\'" "\\1" line))
-              (ignore-errors (process-lines cargo "--list"))))))
+            (mapcar (lambda (line)
+                      (replace-regexp-in-string "\\s-*\\(\\S-+\\).*\\'" "\\1" line))
+                    (ignore-errors (process-lines cargo "--list"))))))
 
 (defun flycheck-rust-valid-crate-type-p (crate-type)
   "Whether CRATE-TYPE is a valid target type for Cargo.
@@ -11688,6 +11987,42 @@ See URL `https://github.com/rust-lang-nursery/rust-clippy'."
              :message (if has-toml "Found" "Missing")
              :face (if has-toml 'success '(bold warning))))))))
 
+(flycheck-define-checker salt-lint
+  "A salt linter which apply common best practices for SaltStack.
+
+See URL `https://salt-lint.readthedocs.io/en/latest/'."
+  :command ("python" "-m" "saltlint" "--json")
+  :standard-input t
+  :error-parser flycheck-salt-lint-parser
+  :error-filter (lambda (errors) (flycheck-sanitize-errors errors))
+  :modes salt-mode)
+
+(defun flycheck-salt-lint-parser (output checker buffer)
+  "Parse salt lint JSON errors from OUTPUT.
+
+The arguments CHECKER and BUFFER are only passed through."
+  (condition-case nil
+      (let* ((json-array-type 'list)
+             (json-object-type 'plist)
+            (filename (buffer-file-name buffer))
+            (errors (json-read-from-string output)))
+        (mapcar (lambda (e)
+                  (flycheck-error-new
+                   :checker checker
+                   :buffer buffer
+                   :filename filename
+                   :level (pcase (plist-get e :severity)
+                            ("HIGH" 'error)
+                            ("MEDIUM" 'warning)
+                            ("LOW" 'warning)
+                            ("INFO" 'info)
+                            (_ 'info))
+                   :line (plist-get e :linenumber)
+                   :column 0
+                   :message (concat (plist-get e :message) (plist-get e :line))
+                   :id (plist-get e :id))) errors))
+    (json-error nil)))
+
 (defvar flycheck-sass-scss-cache-directory nil
   "The cache directory for `sass' and `scss'.")
 
@@ -11711,7 +12046,7 @@ When non-nil, enable the Compass CSS framework, via `--compass'."
 (flycheck-define-checker sass
   "A Sass syntax checker using the Sass compiler.
 
-See URL `http://sass-lang.com'."
+See URL `https://sass-lang.com'."
   :command ("sass"
             "--cache-location" (eval (flycheck-sass-scss-cache-location))
             (option-flag "--compass" flycheck-sass-compass)
@@ -11774,7 +12109,7 @@ See URL `https://www.scala-lang.org/'."
 Note that this syntax checker is not used if
 `flycheck-scalastylerc' is nil or refers to a non-existing file.
 
-See URL `http://www.scalastyle.org'."
+See URL `https://www.scalastyle.org'."
   :command ("scalastyle"
             (config-file "-c" flycheck-scalastylerc)
             source)
@@ -11817,7 +12152,7 @@ See URL `http://www.scalastyle.org'."
 (flycheck-define-checker scheme-chicken
   "A CHICKEN Scheme syntax checker using the CHICKEN compiler `csc'.
 
-See URL `http://call-cc.org/'."
+See URL `https://call-cc.org/'."
   :command ("csc" "-analyze-only" "-local"
             (eval flycheck-scheme-chicken-args)
             source)
@@ -11929,7 +12264,7 @@ See URL `https://github.com/brigade/scss-lint'."
   :modes scss-mode
   :verify
   (lambda (checker)
-    (-when-let
+    (when-let
         (output (flycheck-call-checker-process-for-output
                  checker nil nil "--require=scss_lint_reporter_checkstyle"))
       (let ((reporter-missing
@@ -11947,17 +12282,31 @@ See URL `https://github.com/brigade/scss-lint'."
 (flycheck-define-checker scss-stylelint
   "A SCSS syntax and style checker using stylelint.
 
-See URL `http://stylelint.io/'."
+See URL `https://stylelint.io/'."
   :command ("stylelint"
             (eval flycheck-stylelint-args)
-            "--syntax" "scss"
             (option-flag "--quiet" flycheck-stylelint-quiet)
             (config-file "--config" flycheck-stylelintrc))
   :standard-input t
+  :verify (lambda (_) (flycheck--stylelint-verify 'scss-stylelint))
   :error-parser flycheck-parse-stylelint
   :predicate flycheck-buffer-nonempty-p
   :modes (scss-mode))
 
+(flycheck-define-checker sass-stylelint
+  "A Sass syntax and style checker using stylelint.
+
+See URL `https://stylelint.io/'."
+  :command ("stylelint"
+            (eval flycheck-stylelint-args)
+            (option-flag "--quiet" flycheck-stylelint-quiet)
+            (config-file "--config" flycheck-stylelintrc))
+  :standard-input t
+  :verify (lambda (_) (flycheck--stylelint-verify 'sass-stylelint))
+  :error-parser flycheck-parse-stylelint
+  :predicate flycheck-buffer-nonempty-p
+  :modes (sass-mode))
+
 (flycheck-def-option-var flycheck-scss-compass nil scss
   "Whether to enable the Compass CSS framework.
 
@@ -11969,7 +12318,7 @@ When non-nil, enable the Compass CSS framework, via `--compass'."
 (flycheck-define-checker scss
   "A SCSS syntax checker using the SCSS compiler.
 
-See URL `http://sass-lang.com'."
+See URL `https://sass-lang.com'."
   :command ("scss"
             "--cache-location" (eval (flycheck-sass-scss-cache-location))
             (option-flag "--compass" flycheck-scss-compass)
@@ -12002,7 +12351,7 @@ See URL `http://sass-lang.com'."
 (flycheck-define-checker sh-bash
   "A Bash syntax checker using the Bash shell.
 
-See URL `http://www.gnu.org/software/bash/'."
+See URL `https://www.gnu.org/software/bash/'."
   :command ("bash" "--norc" "-n"
             (eval flycheck-sh-bash-args)
             "--")
@@ -12022,7 +12371,7 @@ See URL `http://www.gnu.org/software/bash/'."
 (flycheck-define-checker sh-posix-dash
   "A POSIX Shell syntax checker using the Dash shell.
 
-See URL `http://gondor.apana.org.au/~herbert/dash/'."
+See URL `https://gondor.apana.org.au/~herbert/dash/'."
   :command ("dash" "-n")
   :standard-input t
   :error-patterns
@@ -12034,7 +12383,7 @@ See URL `http://gondor.apana.org.au/~herbert/dash/'."
 (flycheck-define-checker sh-posix-bash
   "A POSIX Shell syntax checker using the Bash shell.
 
-See URL `http://www.gnu.org/software/bash/'."
+See URL `https://www.gnu.org/software/bash/'."
   :command ("bash" "--posix" "--norc" "-n" "--")
   :standard-input t
   :error-patterns
@@ -12052,7 +12401,7 @@ See URL `http://www.gnu.org/software/bash/'."
 (flycheck-define-checker sh-zsh
   "A Zsh syntax checker using the Zsh shell.
 
-See URL `http://www.zsh.org/'."
+See URL `https://www.zsh.org/'."
   :command ("zsh" "--no-exec" "--no-globalrcs" "--no-rcs" source)
   :error-patterns
   ((error line-start (file-name) ":" line ": " (message) line-end))
@@ -12124,7 +12473,7 @@ See URL `https://github.com/koalaman/shellcheck/'."
 (flycheck-define-checker slim
   "A Slim syntax checker using the Slim compiler.
 
-See URL `http://slim-lang.com'."
+See URL `https://slim-lang.com'."
   :command ("slimrb" "--compile")
   :standard-input t
   :error-patterns
@@ -12184,7 +12533,7 @@ See URL
 (flycheck-define-checker tcl-nagelfar
   "An extensible tcl syntax checker
 
-See URL `http://nagelfar.sourceforge.net/'."
+See URL `https://nagelfar.sourceforge.net/'."
   :command ("nagelfar" "-H" source)
   :error-patterns
   ;; foo.tcl: 29: E Wrong number of arguments (4) to "set"
@@ -12253,19 +12602,31 @@ information about tflint."
   "A Terraform checker using tflint.
 
 See URL `https://github.com/terraform-linters/tflint'."
-  :command ("tflint" "--format=json"
-            (option-list "--var-file=" flycheck-tflint-variable-files concat)
-            source-original)
+  :command ("tflint" "--format=json" "--force"
+            (option-list "--var-file=" flycheck-tflint-variable-files concat))
   :error-parser flycheck-parse-tflint-linter
   :predicate flycheck-buffer-saved-p
   :modes terraform-mode)
 
+(flycheck-def-option-var flycheck-chktex-extra-flags nil tex-chktex
+  "A list of extra arguments to give to chktex.
+This variable works the same way as `tex-chktex-extra-flags': its value
+is a list of strings, where each string is an argument added to chktex.
+
+For example, to ignore warnings 8 and 18, you would set this option to
+
+  \\='(\"-n8\" \"-n18\")."
+  :type '(repeat string)
+  :safe #'flycheck-string-list-p
+  :package-version '(flycheck . "35"))
+
 (flycheck-define-checker tex-chktex
   "A TeX and LaTeX syntax and style checker using chktex.
 
-See URL `http://www.nongnu.org/chktex/'."
+See URL `https://www.nongnu.org/chktex/'."
   :command ("chktex"
             (config-file "--localrc" flycheck-chktexrc)
+            (option-list "" flycheck-chktex-extra-flags concat)
             ;; Compact error messages, and no version information, and execute
             ;; \input statements
             "--verbosity=0" "--quiet" "--inputfiles")
@@ -12276,23 +12637,23 @@ See URL `http://www.nongnu.org/chktex/'."
   :error-filter
   (lambda (errors)
     (flycheck-sanitize-errors (flycheck-increment-error-columns errors)))
-  :modes (latex-mode plain-tex-mode))
+  :modes (latex-mode LaTeX-mode plain-tex-mode plain-TeX-mode))
 
 (flycheck-define-checker tex-lacheck
   "A LaTeX syntax and style checker using lacheck.
 
-See URL `http://www.ctan.org/pkg/lacheck'."
+See URL `https://www.ctan.org/pkg/lacheck'."
   :command ("lacheck" source-inplace)
   :error-patterns
   ((warning line-start
             "\"" (file-name) "\", line " line ": " (message)
             line-end))
-  :modes latex-mode)
+  :modes (latex-mode LaTeX-mode))
 
 (flycheck-define-checker texinfo
   "A Texinfo syntax checker using makeinfo.
 
-See URL `http://www.gnu.org/software/texinfo/'."
+See URL `https://www.gnu.org/software/texinfo/'."
   :command ("makeinfo" "-o" null-device "-")
   :standard-input t
   :error-patterns
@@ -12302,7 +12663,7 @@ See URL `http://www.gnu.org/software/texinfo/'."
    (error line-start
           "-:" line (optional ":" column) ": " (message)
           line-end))
-  :modes texinfo-mode)
+  :modes (texinfo-mode Texinfo-mode))
 
 (flycheck-def-config-file-var flycheck-textlint-config
     textlint "textlintrc.json")
@@ -12329,7 +12690,7 @@ published on NPM."
 
 (defun flycheck--textlint-get-plugin ()
   "Return the textlint plugin for the current mode."
-  (cdr (-first
+  (cdr (seq-find
         (lambda (arg)
           (pcase-let ((`(,mode . _) arg))
             (or (and (booleanp mode) mode) ; mode is t
@@ -12356,7 +12717,7 @@ See URL `https://textlint.github.io/'."
   ;; `flycheck-textlint-plugin-alist'.
   :modes
   (text-mode markdown-mode gfm-mode message-mode adoc-mode
-             mhtml-mode latex-mode org-mode rst-mode)
+             mhtml-mode latex-mode LaTeX-mode org-mode rst-mode)
   :enabled
   (lambda () (flycheck--textlint-get-plugin))
   :verify
@@ -12381,7 +12742,7 @@ to a directory with custom rules, or nil, to not give any custom
 rules to TSLint.
 
 Refer to the TSLint manual at URL
-`http://palantir.github.io/tslint/usage/cli/'
+`https://palantir.github.io/tslint/usage/cli/'
 for more information about the custom directory."
   :type '(choice (const :tag "No custom rules directory" nil)
                  (directory :tag "Custom rules directory"))
@@ -12485,7 +12846,8 @@ See URL `https://github.com/ghdl/ghdl'."
             (option "--ieee=" flycheck-ghdl-ieee-library concat)
             source)
   :error-patterns
-  ((error line-start (file-name) ":" line ":" column ": " (message) line-end))
+  ((warning line-start (file-name) ":" line ":" column ":warning: " (message) line-end)
+   (error line-start (file-name) ":" line ":" column ":error: " (message) line-end))
   :modes vhdl-mode)
 
 (flycheck-def-option-var flycheck-xml-xmlstarlet-xsd-path nil xml-xmlstarlet
@@ -12498,7 +12860,7 @@ See URL `https://github.com/ghdl/ghdl'."
 (flycheck-define-checker xml-xmlstarlet
   "A XML syntax checker and validator using the xmlstarlet utility.
 
-See URL `http://xmlstar.sourceforge.net/'."
+See URL `https://xmlstar.sourceforge.net/'."
   ;; Validate standard input with verbose error messages, and do not dump
   ;; contents to standard output
   :command ("xmlstarlet" "val" "--err" "--quiet"
@@ -12516,13 +12878,21 @@ See URL `http://xmlstar.sourceforge.net/'."
   :safe #'flycheck-string-or-nil-p
   :package-version '(flycheck . "31"))
 
+(flycheck-def-option-var flycheck-xml-xmllint-relaxng-path nil xml-xmllint
+  "An RELAX NG schema to validate against."
+  :type '(choice (const :tag "None" nil)
+                 (file :tag "RELAX NG schema"))
+  :safe #'flycheck-string-or-nil-p
+  :package-version '(flycheck . "34"))
+
 (flycheck-define-checker xml-xmllint
   "A XML syntax checker and validator using the xmllint utility.
 
 The xmllint is part of libxml2, see URL
-`http://www.xmlsoft.org/'."
+`https://gitlab.gnome.org/GNOME/libxml2/-/wikis/home'."
   :command ("xmllint" "--noout"
             (option "--schema" flycheck-xml-xmllint-xsd-path)
+            (option "--relaxng" flycheck-xml-xmllint-relaxng-path)
             "-")
   :standard-input t
   :error-patterns
@@ -12554,7 +12924,7 @@ See URL `https://github.com/nodeca/js-yaml'."
 This syntax checker uses the YAML parser from Ruby's standard
 library.
 
-See URL `http://www.ruby-doc.org/stdlib-2.0.0/libdoc/yaml/rdoc/YAML.html'."
+See URL `https://www.ruby-doc.org/stdlib-2.0.0/libdoc/yaml/rdoc/YAML.html'."
   :command ("ruby" "-ryaml" "-e" "begin;
    YAML.load(STDIN); \
  rescue Exception => e; \
@@ -12568,7 +12938,12 @@ See URL `http://www.ruby-doc.org/stdlib-2.0.0/libdoc/yaml/rdoc/YAML.html'."
   :next-checkers ((warning . yaml-yamllint)
                   (warning . cwl)))
 
-(flycheck-def-config-file-var flycheck-yamllintrc yaml-yamllint ".yamllint")
+(flycheck-def-config-file-var flycheck-yamllintrc
+    yaml-yamllint
+    '(".yamllint"
+      ".yamllint.yaml"
+      ".yamllint.yml"
+      "~/.config/yamllint/config"))
 
 (flycheck-define-checker yaml-yamllint
   "A YAML syntax checker using YAMLLint.
diff --git a/elpa/flycheck-readme.txt b/elpa/flycheck-readme.txt
deleted file mode 100644
index 43e7c7fc..00000000
--- a/elpa/flycheck-readme.txt
+++ /dev/null
@@ -1,30 +0,0 @@
-On-the-fly syntax checking for GNU Emacs 24.
-
-Flycheck is a modern on-the-fly syntax checking extension for GNU Emacs,
-intended as replacement for the older Flymake extension which is part of GNU
-Emacs.
-
-Flycheck automatically checks buffers for errors while you type, and reports
-warnings and errors directly in the buffer and in an optional IDE-like error
-list.
-
-It comes with a rich interface for custom syntax checkers and other
-extensions, and has already many 3rd party extensions adding new features.
-
-Please read the online manual at http://www.flycheck.org for more
-information.  You can open the manual directly from Emacs with `M-x
-flycheck-manual'.
-
-# Setup
-
-Flycheck works best on Unix systems.  It does not officially support Windows,
-but tries to maintain Windows compatibility and should generally work fine on
-Windows, too.
-
-To enable Flycheck add the following to your init file:
-
-   (add-hook 'after-init-hook #'global-flycheck-mode)
-
-Flycheck will then automatically check buffers in supported languages, as
-long as all necessary tools are present.  Use `flycheck-verify-setup' to
-troubleshoot your Flycheck setup.
-- 
2.47.3