master 1ded4a8: Fix movement commands in gomoku

[Eli Zaretskii]

branch: master
commit 1ded4a8b932eb377f5882e7b99ab7365dce43445
Author: Asher Gordon <address@hidden>
Commit: Eli Zaretskii <address@hidden>

    Fix movement commands in gomoku
    
    * lisp/play/gomoku.el (gomoku-mode-map): Bind cursor motion keys
    to gomoku-specific commands.
    (gomoku-point-x, gomoku-move-right, gomoku-move-left): New
    commands.
    (gomoku--intangible, gomoku-move-ne, gomoku-move-se)
    (gomoku-move-nw, gomoku-move-sw): Call gomoku-move-left and
    gomoku-move-right instead of forward-char and backward-char.
    (Bug#40169)
    
    * etc/NEWS: Call out the changes.
---
 etc/NEWS            |  5 +++++
 lisp/play/gomoku.el | 46 ++++++++++++++++++++++++++++++++++++----------
 2 files changed, 41 insertions(+), 10 deletions(-)

diff --git a/etc/NEWS b/etc/NEWS
index 7e578f8..7588b41 100644
--- a/etc/NEWS
+++ b/etc/NEWS
@@ -93,6 +93,11 @@ line numbers that were previously jumped to.
 ** When 'suggest-key-bindings' is non-nil, the completion list of 'M-x'
 shows equivalent key bindings for all commands that have them.
 
+---
+** Movement commands in 'gomoku-mode' are fixed.
+'gomoku-move-sw' and 'gomoku-move-ne' now work correctly, and
+horizontal movements now stop at the edge of the board.
+
 
 * Changes in Specialized Modes and Packages in Emacs 28.1
 
diff --git a/lisp/play/gomoku.el b/lisp/play/gomoku.el
index 6e0061d..4033986 100644
--- a/lisp/play/gomoku.el
+++ b/lisp/play/gomoku.el
@@ -110,8 +110,8 @@ One useful value to include is `turn-on-font-lock' to 
highlight the pieces."
     (define-key map "u" 'gomoku-move-ne)                   ; u
     (define-key map "b" 'gomoku-move-sw)                   ; b
     (define-key map "n" 'gomoku-move-se)                   ; n
-    (define-key map "h" 'backward-char)                            ; h
-    (define-key map "l" 'forward-char)                     ; l
+    (define-key map "h" 'gomoku-move-left)                 ; h
+    (define-key map "l" 'gomoku-move-right)                ; l
     (define-key map "j" 'gomoku-move-down)                 ; j
     (define-key map "k" 'gomoku-move-up)                   ; k
 
@@ -119,11 +119,13 @@ One useful value to include is `turn-on-font-lock' to 
highlight the pieces."
     (define-key map [kp-9] 'gomoku-move-ne)
     (define-key map [kp-1] 'gomoku-move-sw)
     (define-key map [kp-3] 'gomoku-move-se)
-    (define-key map [kp-4] 'backward-char)
-    (define-key map [kp-6] 'forward-char)
+    (define-key map [kp-4] 'gomoku-move-left)
+    (define-key map [kp-6] 'gomoku-move-right)
     (define-key map [kp-2] 'gomoku-move-down)
     (define-key map [kp-8] 'gomoku-move-up)
 
+    (define-key map "\C-b" 'gomoku-move-left)              ; C-b
+    (define-key map "\C-f" 'gomoku-move-right)             ; C-f
     (define-key map "\C-n" 'gomoku-move-down)              ; C-n
     (define-key map "\C-p" 'gomoku-move-up)                ; C-p
 
@@ -146,6 +148,10 @@ One useful value to include is `turn-on-font-lock' to 
highlight the pieces."
     (define-key map [mouse-2] 'gomoku-mouse-play)
     (define-key map [drag-mouse-2] 'gomoku-mouse-play)
 
+    (define-key map [remap backward-char] 'gomoku-move-left)
+    (define-key map [remap left-char] 'gomoku-move-left)
+    (define-key map [remap forward-char] 'gomoku-move-right)
+    (define-key map [remap right-char] 'gomoku-move-right)
     (define-key map [remap previous-line] 'gomoku-move-up)
     (define-key map [remap next-line] 'gomoku-move-down)
     (define-key map [remap move-beginning-of-line] 'gomoku-beginning-of-line)
@@ -954,6 +960,11 @@ If the game is finished, this command requests for another 
game."
         ;; 2 instead of 1 because WINDOW-HEIGHT includes the mode line !
         gomoku-square-height)))
 
+(defun gomoku-point-x ()
+  "Return the board column where point is."
+  (1+ (/ (- (current-column) gomoku-x-offset)
+        gomoku-square-width)))
+
 (defun gomoku-point-y ()
   "Return the board row where point is."
   (1+ (/ (- (count-lines (point-min) (point))
@@ -1143,13 +1154,28 @@ If the game is finished, this command requests for 
another game."
           (skip-chars-forward gomoku--intangible-chars)
           (when (eobp)
             (skip-chars-backward gomoku--intangible-chars)
-            (forward-char -1)))
+            (gomoku-move-left)))
       (skip-chars-backward gomoku--intangible-chars)
       (if (bobp)
           (skip-chars-forward gomoku--intangible-chars)
-        (forward-char -1))))
+        (gomoku-move-left))))
   (setq gomoku--last-pos (point)))
 
+;; forward-char and backward-char don't always move the right number
+;; of characters. Also, these functions check if you're on the edge of
+;; the screen.
+(defun gomoku-move-right ()
+  "Move point right one column on the Gomoku board."
+  (interactive)
+  (when (< (gomoku-point-x) gomoku-board-width)
+    (forward-char gomoku-square-width)))
+
+(defun gomoku-move-left ()
+  "Move point left one column on the Gomoku board."
+  (interactive)
+  (when (> (gomoku-point-x) 1)
+    (backward-char gomoku-square-width)))
+
 ;; previous-line and next-line don't work right with intangible newlines
 (defun gomoku-move-down ()
   "Move point down one row on the Gomoku board."
@@ -1171,25 +1197,25 @@ If the game is finished, this command requests for 
another game."
   "Move point North East on the Gomoku board."
   (interactive)
   (gomoku-move-up)
-  (forward-char))
+  (gomoku-move-right))
 
 (defun gomoku-move-se ()
   "Move point South East on the Gomoku board."
   (interactive)
   (gomoku-move-down)
-  (forward-char))
+  (gomoku-move-right))
 
 (defun gomoku-move-nw ()
   "Move point North West on the Gomoku board."
   (interactive)
   (gomoku-move-up)
-  (backward-char))
+  (gomoku-move-left))
 
 (defun gomoku-move-sw ()
   "Move point South West on the Gomoku board."
   (interactive)
   (gomoku-move-down)
-  (backward-char))
+  (gomoku-move-left))
 
 (defun gomoku-beginning-of-line ()
   "Move point to first square on the Gomoku board row."