feat(tui): ghostty builtin terminfo #36963

Problem:
The builtin terminfo defs don't include xterm-ghostty, so features like
`kTerm_set_underline_style` are missing when building without unibilium.

Solution:
- Add ghostty to `gen_terminfo.lua`.
  - Note: The ncurses defs are somewhat different than what ghostty ships.
- Special-case ghostty in `terminfo_from_builtin`.

runtime/doc/tui.txt

@@ -61,11 +61,13 @@ unlike most other environment variables.
 >
   For this terminal           Set $TERM to                  |builtin-terms|
   -------------------------------------------------------------------------
-  anything libvte-based       vte, vte-256color                   Y
+  ansi                        (unknown)                           Y
-   (e.g. GNOME Terminal)      (aliases: gnome, gnome-256color)
+  Ghostty                     ghostty, xterm-ghostty              Y
   iTerm (original)            iterm, iTerm.app                    N
   iTerm2 (new capabilities)   iterm2, iTerm2.app                  Y
   Konsole                     konsole-256color                    N
+  libvte-based                vte, vte-256color                   Y
+   (e.g. GNOME Terminal)      (aliases: gnome, gnome-256color)
   Linux virtual terminal      linux, linux-256color               Y
   PuTTY                       putty, putty-256color               Y
   rxvt                        rxvt, rxvt-256color                 Y
@@ -76,22 +78,26 @@ unlike most other environment variables.
   Windows/ConEmu              conemu                              Y
   Windows/Cygwin-built Nvim   cygwin                              Y
   Windows/Interix             interix                             Y
-  Windows/VTP console         vtpcon                              Y
   Windows/legacy console      win32con                            Y
+  Windows/VTP console         vtpcon                              Y
   xterm or compatible         xterm, xterm-256color               Y
 <
 
 					*builtin-terms* *builtin_terms*
-If a |terminfo| database is not available or there is no entry for the current
+Nvim will map |$TERM| to a builtin entry according to the above table if:
-terminal, Nvim will map |$TERM| to a builtin entry according to the above
+
-table, or "ansi" if there is no match. For example "TERM=putty-256color" will
+- a |terminfo| database is not available on the system
-be mapped to the builtin "putty" entry. See also |tui-colors|.
+- no terminfo entry found for the current detected terminal
+- Nvim was built without terminfo support (`has('terminfo')==0`)
 
 The builtin terminfo is not combined with any external terminfo database, nor
 can it be used in preference to one.  You can thus entirely override any
 omissions or out-of-date information in the builtin terminfo database by
 supplying an external one with entries for the terminal type.
 
+For example "TERM=putty-256color" will be mapped to the builtin "putty" entry.
+See also |tui-colors|.
+
 Settings depending on terminal			*term-dependent-settings*
 
 If you want to set terminal-dependent options or mappings, you can do this in

src/gen/gen_terminfo.lua

@@ -20,6 +20,7 @@ local target_enum = 'src/nvim/tui/terminfo_enum_defs.h'
 
 local entries = {
   { 'ansi', 'ansi_terminfo' },
+  { 'ghostty', 'ghostty_terminfo' }, -- Note: ncurses defs do not exactly match what ghostty ships.
   { 'interix', 'interix_8colour_terminfo' },
   { 'iterm2', 'iterm_256colour_terminfo' },
   { 'linux', 'linux_16colour_terminfo' },

src/nvim/tui/terminfo.c

@@ -70,7 +70,10 @@ bool terminfo_is_bsd_console(const char *term)
 /// @return [allocated] terminfo structure
 const TerminfoEntry *terminfo_from_builtin(const char *term, char **termname)
 {
-  if (terminfo_is_term_family(term, "xterm")) {
+  if (strequal(term, "ghostty") || strequal(term, "xterm-ghostty")) {
+    *termname = "ghostty";
+    return &ghostty_terminfo;
+  } else if (terminfo_is_term_family(term, "xterm")) {
     *termname = "xterm";
     return &xterm_256colour_terminfo;
   } else if (terminfo_is_term_family(term, "screen")) {

src/nvim/tui/terminfo_builtin.h

@@ -82,6 +82,145 @@ static const TerminfoEntry ansi_terminfo = {
   },
 };
 
+static const TerminfoEntry ghostty_terminfo = {
+  .bce = true,
+  .has_Tc_or_RGB = false,
+  .Su = false,
+  .max_colors = 0x100,
+  .lines = 24,
+  .columns = 80,
+  .defs = {
+    [kTerm_carriage_return] = "\r",
+    [kTerm_change_scroll_region] = "\033[%i%p1%d;%p2%dr",
+    [kTerm_clear_screen] = "\033[H\033[2J",
+    [kTerm_clr_eol] = "\033[K",
+    [kTerm_clr_eos] = "\033[J",
+    [kTerm_cursor_address] = "\033[%i%p1%d;%p2%dH",
+    [kTerm_cursor_down] = "\n",
+    [kTerm_cursor_invisible] = "\033[?25l",
+    [kTerm_cursor_left] = "\b",
+    [kTerm_cursor_home] = "\033[H",
+    [kTerm_cursor_normal] = "\033[?12l\033[?25h",
+    [kTerm_cursor_up] = "\033[A",
+    [kTerm_cursor_right] = "\033[C",
+    [kTerm_delete_line] = "\033[M",
+    [kTerm_enter_bold_mode] = "\033[1m",
+    [kTerm_enter_ca_mode] = "\033[?1049h",
+    [kTerm_enter_italics_mode] = "\033[3m",
+    [kTerm_enter_reverse_mode] = "\033[7m",
+    [kTerm_enter_standout_mode] = "\033[7m",
+    [kTerm_enter_underline_mode] = "\033[4m",
+    [kTerm_erase_chars] = "\033[%p1%dX",
+    [kTerm_exit_attribute_mode] = "\033(B\033[m",
+    [kTerm_exit_ca_mode] = "\033[?1049l",
+    [kTerm_from_status_line] = "\a",
+    [kTerm_insert_line] = "\033[L",
+    [kTerm_keypad_local] = "\033[?1l\033>",
+    [kTerm_keypad_xmit] = "\033[?1h\033=",
+    [kTerm_parm_delete_line] = "\033[%p1%dM",
+    [kTerm_parm_down_cursor] = "\033[%p1%dB",
+    [kTerm_parm_insert_line] = "\033[%p1%dL",
+    [kTerm_parm_left_cursor] = "\033[%p1%dD",
+    [kTerm_parm_right_cursor] = "\033[%p1%dC",
+    [kTerm_parm_up_cursor] = "\033[%p1%dA",
+    [kTerm_set_a_background] = "\033[%?%p1%{8}%<%t4%p1%d%e%p1%{16}%<%t10%p1%{8}%-%d%e48;5;%p1%d%;m",
+    [kTerm_set_a_foreground] = "\033[%?%p1%{8}%<%t3%p1%d%e%p1%{16}%<%t9%p1%{8}%-%d%e38;5;%p1%d%;m",
+    [kTerm_set_attributes] = "%?%p9%t\033(0%e\033(B%;\033[0%?%p6%t;1%;%?%p2%t;4%;%?%p1%p3%|%t;7%;%?%p5%t;2%;%?%p7%t;8%;m",
+    [kTerm_set_lr_margin] = "\033[?69h\033[%i%p1%d;%p2%ds",
+    [kTerm_to_status_line] = "\033]2;",
+    [kTerm_reset_cursor_style] = "\033[2 q",
+    [kTerm_set_cursor_style] = "\033[%p1%d q",
+    [kTerm_enter_strikethrough_mode] = "\033[9m",
+    [kTerm_set_rgb_foreground] = NULL,
+    [kTerm_set_rgb_background] = NULL,
+    [kTerm_set_cursor_color] = NULL,
+    [kTerm_reset_cursor_color] = NULL,
+    [kTerm_set_underline_style] = "\033[4\072%p1%dm",
+  },
+  .keys = {
+    [kTermKey_backspace] = {"\177", NULL},
+    [kTermKey_beg] = {NULL, NULL},
+    [kTermKey_btab] = {"\033[Z", NULL},
+    [kTermKey_clear] = {NULL, NULL},
+    [kTermKey_dc] = {"\033[3~", "\033[3;2~"},
+    [kTermKey_end] = {"\033OF", "\033[1;2F"},
+    [kTermKey_find] = {NULL, NULL},
+    [kTermKey_home] = {"\033OH", "\033[1;2H"},
+    [kTermKey_ic] = {"\033[2~", "\033[2;2~"},
+    [kTermKey_npage] = {"\033[6~", NULL},
+    [kTermKey_ppage] = {"\033[5~", NULL},
+    [kTermKey_select] = {NULL, NULL},
+    [kTermKey_suspend] = {NULL, NULL},
+    [kTermKey_undo] = {NULL, NULL},
+  },
+  .f_keys = {
+    // note: offset by one, f_keys[0] is F1 and so on
+    [0] = "\033OP",
+    [1] = "\033OQ",
+    [2] = "\033OR",
+    [3] = "\033OS",
+    [4] = "\033[15~",
+    [5] = "\033[17~",
+    [6] = "\033[18~",
+    [7] = "\033[19~",
+    [8] = "\033[20~",
+    [9] = "\033[21~",
+    [10] = "\033[23~",
+    [11] = "\033[24~",
+    [12] = "\033[1;2P",
+    [13] = "\033[1;2Q",
+    [14] = "\033[1;2R",
+    [15] = "\033[1;2S",
+    [16] = "\033[15;2~",
+    [17] = "\033[17;2~",
+    [18] = "\033[18;2~",
+    [19] = "\033[19;2~",
+    [20] = "\033[20;2~",
+    [21] = "\033[21;2~",
+    [22] = "\033[23;2~",
+    [23] = "\033[24;2~",
+    [24] = "\033[1;5P",
+    [25] = "\033[1;5Q",
+    [26] = "\033[1;5R",
+    [27] = "\033[1;5S",
+    [28] = "\033[15;5~",
+    [29] = "\033[17;5~",
+    [30] = "\033[18;5~",
+    [31] = "\033[19;5~",
+    [32] = "\033[20;5~",
+    [33] = "\033[21;5~",
+    [34] = "\033[23;5~",
+    [35] = "\033[24;5~",
+    [36] = "\033[1;6P",
+    [37] = "\033[1;6Q",
+    [38] = "\033[1;6R",
+    [39] = "\033[1;6S",
+    [40] = "\033[15;6~",
+    [41] = "\033[17;6~",
+    [42] = "\033[18;6~",
+    [43] = "\033[19;6~",
+    [44] = "\033[20;6~",
+    [45] = "\033[21;6~",
+    [46] = "\033[23;6~",
+    [47] = "\033[24;6~",
+    [48] = "\033[1;3P",
+    [49] = "\033[1;3Q",
+    [50] = "\033[1;3R",
+    [51] = "\033[1;3S",
+    [52] = "\033[15;3~",
+    [53] = "\033[17;3~",
+    [54] = "\033[18;3~",
+    [55] = "\033[19;3~",
+    [56] = "\033[20;3~",
+    [57] = "\033[21;3~",
+    [58] = "\033[23;3~",
+    [59] = "\033[24;3~",
+    [60] = "\033[1;4P",
+    [61] = "\033[1;4Q",
+    [62] = "\033[1;4R",
+  },
+};
+
 static const TerminfoEntry interix_8colour_terminfo = {
   .bce = true,
   .has_Tc_or_RGB = false,