Handle truncate-lines in customize-group

* lisp/cus-edit.el (custom-group--draw-horizontal-line): New
function to draw horizontal lines which handles a non-nil value of
'truncate-lines'.  (Bug#25308)
(custom-group-value-create): Use it.

Co-authored-by: Jonas Bernoulli <jonas@bernoul.li>

diff --git a/lisp/cus-edit.el b/lisp/cus-edit.el
index b9fd3e0a2d41ed60b88b7de6668887e8fc81c268..081d4c9213efbfe87b49025c599b7ee305ceec95 100644 (file)
--- a/lisp/cus-edit.el
+++ b/lisp/cus-edit.el
@@ -4062,6 +4062,22 @@ If GROUPS-ONLY is non-nil, return only those members that are groups."
          (push entry members)))
       (nreverse members))))
 
+(defun custom-group--draw-horizontal-line ()
+  "Draw a horizontal line at point.
+This works for both graphical and text displays."
+  (let ((p (point)))
+    (insert "\n")
+    (put-text-property p (1+ p) 'face '(:underline t))
+    (overlay-put (make-overlay p (1+ p))
+                'before-string
+                (propertize "\n" 'face '(:underline t)
+                            'display
+                             (list 'space :align-to
+                                   `(+ (0 . right)
+                                       ,(min (window-hscroll)
+                                             (- (line-end-position)
+                                                (line-beginning-position)))))))))
+
 (defun custom-group-value-create (widget)
   "Insert a customize group for WIDGET in the current buffer."
   (unless (eq (widget-get widget :custom-state) 'hidden)
@@ -4188,15 +4204,7 @@ If GROUPS-ONLY is non-nil, return only those members that are groups."
 
          ;; Nested style.
          (t                            ;Visible.
-          ;; Draw a horizontal line (this works for both graphical
-          ;; and text displays):
-          (let ((p (point)))
-            (insert "\n")
-            (put-text-property p (1+ p) 'face '(:underline t))
-            (overlay-put (make-overlay p (1+ p))
-                         'before-string
-                         (propertize "\n" 'face '(:underline t)
-                                     'display '(space :align-to 999))))
+           (custom-group--draw-horizontal-line)
 
           ;; Add parent groups references above the group.
           (when (eq level 1)
@@ -4287,13 +4295,7 @@ If GROUPS-ONLY is non-nil, return only those members that are groups."
             (widget-put widget :children children)
             (custom-group-state-update widget))
           ;; End line
-          (let ((p (1+ (point))))
-            (insert "\n\n")
-            (put-text-property p (1+ p) 'face '(:underline t))
-            (overlay-put (make-overlay p (1+ p))
-                         'before-string
-                         (propertize "\n" 'face '(:underline t)
-                                     'display '(space :align-to 999))))))))
+           (custom-group--draw-horizontal-line)))))
 
 (defvar custom-group-menu
   `(("Set for Current Session" custom-group-set