(feat) flycheck additions

- Flycheck automatically runs on shell scripts and elisp code
- C-; ? opens flycheck's error list in another buffer and selects it
- If C-; ? on an org buffer, it also registers proselint and triggers check.
- Commentary text added

1 files changed, 68 insertions, 23 deletions

diff --git a/modules/flycheck-config.el b/modules/flycheck-config.el
index 37b8e657..82ff56cd 100644
--- a/modules/flycheck-config.el
+++ b/modules/flycheck-config.el
@@ -3,44 +3,89 @@
 
 ;;; Commentary:
 
+;; This file configures Flycheck for on-demand syntax and grammar checking.
+;; - Flycheck starts automatically only in sh-mode and emacs-lisp-mode
+
+;; - This binds a custom helper (=cj/flycheck-list-errors=) to “C-; ?”
+;;   for popping up Flycheck's error list in another window.
+
+;; - It also customizes Checkdoc to suppress only the “sentence-end-double-space”
+;;   and “warn-escape” warnings.
+
+;; - It registers a Proselint checker for prose files
+;;   (text-mode, markdown-mode, gfm-mode).
+
+;; Note: I do use proselint quite a bit in emails and org-mode files. However, some
+;; org-files can be large and running proselint on them will slow Emacs to a crawl.
+;; Therefore, hitting "C-; ?" also runs cj/flycheck-prose-on-demand if in an org buffer.
+;;
+;; The cj/flycheck-prose-on-demand function:
+;; - Turns on flycheck for the local buffer
+;; - ensures proselint is added
+;; - triggers an immediate check
+;;
+;; Since this is called within cj/flycheck-list-errors, flycheck's error list will still
+;; display and the focus transferred to that buffer.
+
+;; OS Dependencies:
+;; proselint (in the Arch AUR)
+
 ;;; Code:
 
 (defun cj/prose-helpers-on ()
   "Ensure that abbrev, flyspell, and flycheck are all on."
   (interactive)
   (if (not (abbrev-mode))
-	  (abbrev-mode))
+      (abbrev-mode))
   ;;  (flyspell-on-for-buffer-type)
   (if (not (flycheck-mode))
-	  (flycheck-mode)))
+      (flycheck-mode)))
 
 ;; ---------------------------------- Linting ----------------------------------
 
-(defun cj/flycheck-list-errors ()
-  "Display flycheck's error list and switch to its buffer."
-  (interactive)
-  (flycheck-list-errors)
-  (switch-to-buffer-other-window "*Flycheck errors*"))
-
 (use-package flycheck
-  :defer .5
-  :hook (sh-mode emacs-lisp-mode)
-  :bind ("C-; ?" . cj/flycheck-list-errors)
+  :defer t
+  :commands (flycheck-list-errors
+             cj/flycheck-list-errors)
+  :hook ((sh-mode emacs-lisp-mode) . flycheck-mode)
+  :bind (("C-; ?" . cj/flycheck-list-errors))
+  :custom
+  ;; Only disable these two Checkdoc warnings; leave all others intact.
+  (checkdoc-arguments
+   '(("sentence-end-double-space" nil)
+     ("warn-escape"               nil)))
   :config
-  ;; don't warn about double-spaces after period.
-  (setq-default checkdoc-arguments '("sentence-end-double-space" nil
-									 "warn-escape" nil))
 
-  ;; proselint must be installed via the OS
+  ;; Define the prose checker (installed separately via OS).
   (flycheck-define-checker proselint
-	"A linter for prose."
-	:command ("proselint" source-inplace)
-	:error-patterns
-	((warning line-start (file-name) ":" line ":" column ": "
-			  (id (one-or-more (not (any " "))))
-			  (message) line-end))
-	:modes (text-mode markdown-mode gfm-mode))
-  (add-to-list 'flycheck-checkers 'proselint))
+    "A linter for prose."
+    :command ("proselint" source-inplace)
+    :error-patterns
+    ((warning line-start (file-name) ":" line ":" column ": "
+              (id (one-or-more (not (any " "))))
+              (message) line-end))
+    :modes (text-mode markdown-mode gfm-mode org-mode))
+  (add-to-list 'flycheck-checkers 'proselint)
+
+  (defun cj/flycheck-list-errors ()
+    "Display flycheck's error list and switch to its buffer.
+Runs flycheck-prose-on-demand if in an org-buffer."
+    (interactive)
+    (when (derived-mode-p 'org-mode)
+      (cj/flycheck-prose-on-demand))
+
+    (flycheck-list-errors)
+    (switch-to-buffer-other-window "*Flycheck errors*"))
+
+  (defun cj/flycheck-prose-on-demand ()
+    "Enable Flycheck+Proselint in this buffer, run it, and show errors."
+    (interactive)
+    ;; turn on Flycheck locally
+    (flycheck-mode 1)
+    ;; ensure proselint is valid for org/text
+    (flycheck-add-mode 'proselint major-mode)
+    ;; trigger immediate check
+    (flycheck-buffer)))
 
 (provide 'flycheck-config)
 ;;; flycheck-config.el ends here