Bug#965029: console-setup: fonts missing numerous unicode->font mappings for box-drawing characters

[Nick Black <dankamongmen@gmail.com>]

Package: console-setup
Version: 1.196
Severity: wishlist
Tags: upstream

Dear Maintainer,

While working on Notcurses (https://notcurses.com), I realized that numerous
Unicode Box-Drawing Characters resolve to the missing glyph (U+FFFD), despite
being well-simulated by glyphs present in the font. I suggest that these
Unicode->font mappings be added to the various psf files. Notcurses currently
adds them (if not already present) at application start time, and I can verify
that it significantly improves the console experience.

I'm happy to make these patches and send them upstream, but Anton Zinoviev
requested that I file a bug here.

I consider the following wide strings to be acceptable fallback sets (taken
from Notcurses src/lib/linux.c):

      .ws = L"/╱",
      .ws = L"\\╲",
      .ws = L"X╳",
      .ws = L"└┕┖┗╘╙╚╰",
      .ws = L"┘┙┚┛╛╜╝╯",
      .ws = L"┌┍┎┏╒╓╔╭",
      .ws = L"┐┑┒┓╕╖╗╮",
      .ws = L"─━┄┅┈┉╌╍═╼╾",
      .ws = L"│┃┆┇┊┋╎╏║╽╿",
      .ws = L"├┝┞┟┠┡┢┣╞╟╠",
      .ws = L"┤┥┦┧┨┩┪┫╡╢╣",
      .ws = L"┬┭┮┯┰┱┲┳╤╥╦",
      .ws = L"┴┵┶┷┸┹┺┻╧╨╩",
      .ws = L"┼┽┾┿╀╁╂╃╄╅╆╇╈╉╊╋╪╫╬",

Let me know how I can make myself useful.



-- System Information:
Debian Release: bullseye/sid
  APT prefers unstable
  APT policy: (300, 'unstable'), (1, 'experimental')
Architecture: amd64 (x86_64)

Kernel: Linux 5.7.8nlb (SMP w/64 CPU threads)
Kernel taint flags: TAINT_PROPRIETARY_MODULE, TAINT_WARN, TAINT_OOT_MODULE, TAINT_UNSIGNED_MODULE
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8), LANGUAGE not set
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)

Versions of packages console-setup depends on:
ii  console-setup-linux     1.196
ii  debconf                 1.5.74
ii  keyboard-configuration  1.196
ii  xkb-data                2.29-2

console-setup recommends no packages.

Versions of packages console-setup suggests:
ii  locales   2.30-8
ii  lsb-base  11.1.0

Versions of packages keyboard-configuration depends on:
ii  debconf                 1.5.74
ii  liblocale-gettext-perl  1.07-4

Versions of packages console-setup-linux depends on:
ii  init-system-helpers     1.58
ii  kbd                     2.0.4-4
ii  keyboard-configuration  1.196

console-setup-linux suggests no packages.

Versions of packages console-setup is related to:
pn  console-common        <none>
pn  console-data          <none>
pn  console-tools         <none>
ii  gnome-control-center  1:3.36.4-1
ii  kbd                   2.0.4-4
ii  systemd               245.6-2

-- debconf information:
  console-setup/store_defaults_in_debconf_db: true
* keyboard-configuration/other:
  console-setup/codesetcode: Arabic
* keyboard-configuration/toggle: No toggling
  console-setup/guess_font:
  keyboard-configuration/unsupported_config_layout: true
* keyboard-configuration/modelcode: pc105
  console-setup/fontsize-text47: 8x16
* keyboard-configuration/store_defaults_in_debconf_db: true
* keyboard-configuration/variant: English (US)
* console-setup/codeset47: . Arabic
  keyboard-configuration/unsupported_layout: true
* console-setup/fontface47: VGA
* keyboard-configuration/ctrl_alt_bksp: true
* keyboard-configuration/altgr: The default for the keyboard layout
* console-setup/fontsize-fb47: 8x16
* keyboard-configuration/variantcode:
  keyboard-configuration/unsupported_config_options: true
* keyboard-configuration/optionscode: terminate:ctrl_alt_bksp
  console-setup/use_system_font:
* keyboard-configuration/compose: No compose key
* console-setup/charmap47: UTF-8
* keyboard-configuration/layout:
  debian-installer/console-setup-udeb/title:
  console-setup/fontsize: 8x16
* keyboard-configuration/xkb-keymap: us
  console-setup/framebuffer_only:
* keyboard-configuration/model: Generic 105-key PC (intl.)
  keyboard-configuration/unsupported_options: true
* keyboard-configuration/switch: No temporary switch
* keyboard-configuration/layoutcode: us