From c9cb29b2e0caa516bf0fc33e0ec6682d4c837445 Mon Sep 17 00:00:00 2001
From: Jason Blevins <jrblevin@sdf.org>
Date: Tue, 9 May 2017 21:37:44 -0400
Subject: [PATCH] Command for toggling GFM task list items

Adds `C-c C-c C-x` and a menu item.
---
 README.md              |  4 +++-
 markdown-mode.el       | 35 ++++++++++++++++++++++++++---------
 tests/markdown-test.el |  7 +++++++
 3 files changed, 36 insertions(+), 10 deletions(-)

diff --git a/README.md b/README.md
index 19bbd7a..d54c519 100644
--- a/README.md
+++ b/README.md
@@ -717,7 +717,9 @@ by `markdown-mode` and `gfm-mode` as described below.
   (Emacs buttons) in both `markdown-mode` and `gfm-mode` when
   `markdown-make-gfm-checkboxes-buttons` is set to a non-nil value
   (and it is set to t by default).  These checkboxes can be
-  toggled by clicking `mouse-1` or pressing <kbd>RET</kbd> over the button.
+  toggled by clicking `mouse-1`, pressing <kbd>RET</kbd> over the button,
+  or by pressing <kbd>C-c C-x C-x</kbd> with the point anywhere in the task
+  list item.
 
 * **Wiki links:** Generic wiki links are supported in
   `markdown-mode`, but in `gfm-mode` specifically they will be
diff --git a/markdown-mode.el b/markdown-mode.el
index 66ded47..f13442d 100644
--- a/markdown-mode.el
+++ b/markdown-mode.el
@@ -737,7 +737,9 @@
 ;;   (Emacs buttons) in both `markdown-mode' and `gfm-mode' when
 ;;   `markdown-make-gfm-checkboxes-buttons' is set to a non-nil value
 ;;   (and it is set to t by default).  These checkboxes can be
-;;   toggled by clicking `mouse-1` or pressing `RET` over the button.
+;;   toggled by clicking `mouse-1`, pressing `RET` over the button,
+;;   or by pressing `C-c C-x C-x` with the point anywhere in the task
+;;   list item.
 ;;
 ;; * **Wiki links:** Generic wiki links are supported in
 ;;   `markdown-mode', but in `gfm-mode' specifically they will be
@@ -4600,6 +4602,7 @@ Assumes match data is available for `markdown-regex-italic'."
     (define-key map (kbd "C-c C-x l") 'markdown-promote)
     (define-key map (kbd "C-c C-x r") 'markdown-demote)
     (define-key map (kbd "C-c C-x m") 'markdown-insert-list-item)
+    (define-key map (kbd "C-c C-x C-x") 'markdown-toggle-gfm-checkbox)
     map)
   "Keymap for Markdown major mode.")
 
@@ -4667,7 +4670,8 @@ See also `markdown-mode-map'.")
      ["Exdent List Item" markdown-promote]
      ["Move List Item Up" markdown-move-up]
      ["Move List Item Down" markdown-move-down]
-     ["Renumber List" markdown-cleanup-list-numbers])
+     ["Renumber List" markdown-cleanup-list-numbers]
+     ["Toggle Task List Item" markdown-toggle-gfm-checkbox])
     ("Links & Images"
      ["Plain URL" markdown-insert-uri]
      ["Inline Link" markdown-insert-inline-link-dwim]
@@ -6542,7 +6546,7 @@ if ARG is omitted or nil."
                                                            (3 markdown-markup-face))))))
 
 
-;;; GFM Checkboxes as Buttons =================================================
+;;; GFM Checkboxes ============================================================
 
 (require 'button)
 
@@ -6550,17 +6554,30 @@ if ARG is omitted or nil."
   'follow-link t
   'face 'markdown-gfm-checkbox-face
   'mouse-face 'markdown-highlight-face
-  'action #'markdown-toggle-gfm-checkbox)
+  'action #'markdown-toggle-gfm-checkbox-button)
 
-(defun markdown-toggle-gfm-checkbox (button)
+(defun markdown-toggle-gfm-checkbox ()
+  "Toggle GFM checkbox at point."
+  (interactive)
+  (save-match-data
+    (save-excursion
+      (let ((bounds (markdown-cur-list-item-bounds)))
+        (when bounds
+          ;; Move to beginning of task list item
+          (goto-char (cl-first bounds))
+          ;; Advance to column of first non-whitespace after marker
+          (forward-char (cl-fourth bounds))
+          (cond ((looking-at "\\[ \\]")
+                 (replace-match "[x]" nil t))
+                ((looking-at "\\[[xX]\\]")
+                 (replace-match "[ ]" nil t))))))))
+
+(defun markdown-toggle-gfm-checkbox-button (button)
   "Toggle GFM checkbox BUTTON on click."
   (save-match-data
     (save-excursion
       (goto-char (button-start button))
-      (cond ((looking-at "\\[ \\]")
-             (replace-match "[x]" nil t))
-            ((looking-at "\\[[xX]\\]")
-             (replace-match "[ ]" nil t))))))
+      (markdown-toggle-gfm-checkbox))))
 
 (defun markdown-make-gfm-checkboxes-buttons (start end)
   "Make GFM checkboxes buttons in region between START and END."
diff --git a/tests/markdown-test.el b/tests/markdown-test.el
index 631ef9e..4bda697 100644
--- a/tests/markdown-test.el
+++ b/tests/markdown-test.el
@@ -3150,6 +3150,13 @@ x: x
 
        Another paragraph of item 2"))))
 
+(ert-deftest test-markdown-lists/toggle-gfm-checkbox ()
+  (markdown-test-string "   -   [X] GFM task list item"
+    (markdown-toggle-gfm-checkbox)
+    (should (string-equal (buffer-string) "   -   [ ] GFM task list item"))
+    (markdown-toggle-gfm-checkbox)
+    (should (string-equal (buffer-string) "   -   [x] GFM task list item"))))
+
 ;;; Outline minor mode tests:
 
 (ert-deftest test-markdown-outline/navigation ()
-- 
2.11.4.GIT