Add customizable to display raw bytes as hex

* src/xdisp.c (get_next_display_element): Dispatch used format string
for unprintables based on new display-raw-bytes-as-hex variable.
(display-raw-bytes-as-hex): New variable.  (Bug#27122)

* lisp/cus-start.el: Add defcustom form for display-raw-bytes-as-hex.

* doc/emacs/display.texi: Document the new variable.
* etc/NEWS: Mention display-raw-bytes-as-hex.

* test/manual/redisplay-testsuite.el (test-redisplay-5-toggle)
(test-redisplay-5): New tests.
(test-redisplay): Call test-redisplay-5.

1 files changed, 1 insertions, 0 deletions

diff --git a/lisp/cus-start.el b/lisp/cus-start.el
index 4253d40b759..744fe7f69ee 100644
--- a/lisp/cus-start.el
+++ b/lisp/cus-start.el
@@ -583,6 +583,7 @@ since it could result in memory overflow and make Emacs crash."
                        (const :tag "Fit (t)" :value t)
                        (const :tag "Grow only" :value grow-only))
               "25.1")
+             (display-raw-bytes-as-hex display boolean "26.1")
              ;; xfaces.c
              (scalable-fonts-allowed display boolean "22.1")
              ;; xfns.c