Subject: Missing right border on composed text used in 'display property
From: Clément Pit-Claudel <[email-masked]>
To: bug-gnu-emacs <[email-masked]>
Date: Fri, 17 Apr 2020 15:44:36 -0400
List-Id: <debbugs-submit.debbugs.gnu.org>

Hi all,

With the following sample code, I observe the results shown in the attached image.  The first two "ab" have a border, but the last one only has three-quarters of its border: the right side is missing.

(defface my-button
  '((t :box(:line-width -4 :style released-button)
       :background"lightgrey":foreground"black"))
  "Button face")

(with-current-buffer (get-buffer-create "button")
  (insert "\n")
  (insert (propertize "ab" 'face 'my-button))
  (insert " ")
  (insert (propertize (compose-chars ?a '(Br . Bl) ?b) 'face 'my-button))
  (insert " ")
  (insert (propertize "ab" 'display (compose-chars ?a '(Br . Bl) ?b) 'face 'my-button))
  (insert " ")
  (pop-to-buffer-same-window (current-buffer)))

Clément.

In GNU Emacs 28.0.50 (build 5, x86_64-pc-linux-gnu, GTK+ Version 3.22.30, cairo version 1.15.10)
 of 2020-03-15 built on clem-w50-mint
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