feat(highlight): support more SGR attributes #37901

Problem:
TUI does not support several standard SGR text attributes:
- dim/faint (SGR 2)
- blink (SGR 5)
- conceal (SGR 8)
- overline (SGR 53)
This means that when a program running in the embedded terminal emits
one of these escape codes, we drop it and don't surface it to the
outer terminal.

Solution:
- Add support for those attributes.
- Also add corresponding flags to `nvim_set_hl` opts, so users can set
  these attributes in highlight groups.
  - refactor(highlight): widen `HlAttrFlags` from `int16_t` to `int32_t`
    Widen the `rgb_ae_attr` and `cterm_ae_attr` fields in HlAttrs from
    int16_t to int32_t to make room for new highlight attribute flags,
    since there was only one spare bit left.
  - The C flag is named HL_CONCEALED to avoid colliding with the
    existing HL_CONCEAL in syntax.h (which is a syntax group flag, not
    an SGR attribute).
- Also note that libvterm doesn't currently support the dim and overline
  attributes, so e.g. `printf '\e[2mThis should be dim\n'` and `printf
  '\e[53mThis should have an overline\n'` are still not rendered
  correctly when run from the embedded terminal.

runtime/doc/api-ui-events.txt

@@ -335,6 +335,10 @@ numerical highlight ids to the actual attributes.
 	`underdotted`:		underdotted text. The dots have `special` color.
 	`underdashed`:		underdashed text. The dashes have `special` color.
 	`altfont`:		alternative font.
+	`dim`:			half-bright/faint text.
+	`blink`:		blinking text.
+	`conceal`:		concealed/hidden text.
+	`overline`:		overlined text.
 	`blend`:		blend level (0-100). Could be used by UIs to
 				support blending floating windows to the
 				background or to signal a transparent cursor.
@@ -504,6 +508,10 @@ is not active. New UIs should implement |ui-linegrid| instead.
 	`underdouble`:	double underlined text. The lines have `special` color.
 	`underdotted`:	underdotted text. The dots have `special` color.
 	`underdashed`:	underdashed text. The dashes have `special` color.
+	`dim`:		half-bright/faint text.
+	`blink`:	blinking text.
+	`conceal`:	concealed/hidden text.
+	`overline`:	overlined text.
 
 ["put", text] ~
 	The (utf-8 encoded) string `text` is put at the cursor position

runtime/doc/api.txt

@@ -1553,6 +1553,11 @@ nvim_set_hl({ns_id}, {name}, {val})                            *nvim_set_hl()*
                  • sp: color name or "#RRGGBB"
                  • blend: integer between 0 and 100
                  • bold: boolean
+                 • altfont: boolean
+                 • blink: boolean
+                 • dim: boolean
+                 • conceal: boolean
+                 • overline: boolean
                  • standout: boolean
                  • underline: boolean
                  • undercurl: boolean

runtime/doc/news.txt

@@ -248,6 +248,8 @@ HIGHLIGHTS
 • |hl-OkMsg| |hl-StderrMsg| |hl-StdoutMsg|
 • |hl-SnippetTabstopActive| highlights the currently active tabstop.
 • |hl-PmenuBorder| |hl-PmenuShadow| |hl-PmenuShadowThrough| see 'pumborder'.
+• |nvim_set_hl()| and |nvim_get_hl()| support the SGR attributes "dim",
+  "blink", "conceal", and "overline".
 
 LSP
 
@@ -404,6 +406,8 @@ TUI
 • |TermResponse| now supports DA1 and APC query responses.
 • Native progress bars are displayed for |Progress| events using the OSC 9;4
   sequence.
+• The TUI now renders the SGR dim (faint), blink, conceal, and overline
+  attributes.
 
 UI
 

runtime/doc/syntax.txt

@@ -5059,7 +5059,7 @@ the same syntax file on all UIs.
 					*underdouble* *underdotted*
 					*underdashed* *inverse* *italic*
 					*standout* *strikethrough* *altfont*
-					*nocombine*
+					*dim* *blink* *hl-conceal* *overline* *nocombine*
 cterm={attr-list}			*attr-list* *highlight-cterm* *E418*
 	attr-list is a comma-separated list (without spaces) of the
 	following items (in any order):
@@ -5075,6 +5075,10 @@ cterm={attr-list}			*attr-list* *highlight-cterm* *E418*
 		italic
 		standout
 		altfont
+		dim		half-bright/faint text
+		blink		blinking text
+		conceal		concealed/hidden text
+		overline	overlined text
 		nocombine	override attributes instead of combining them
 		NONE		no attributes used (used to reset it)
 

runtime/doc/vimfn.txt

@@ -11046,6 +11046,10 @@ synIDattr({synID}, {what} [, {mode}])                              *synIDattr()*
 		"strikethrough"	"1" if struckthrough
 		"altfont"	"1" if alternative font
 		"nocombine"	"1" if nocombine
+		"dim"	"1" if half-bright/dimmed
+		"blink"	"1" if blinking
+		"conceal"	"1" if concealed
+		"overline"	"1" if overlined
 
 		Returns an empty string on error.
 

runtime/lua/vim/_meta/api.lua

@@ -2208,6 +2208,11 @@ function vim.api.nvim_set_decoration_provider(ns_id, opts) end
 --- - sp: color name or "#RRGGBB"
 --- - blend: integer between 0 and 100
 --- - bold: boolean
+--- - altfont: boolean
+--- - blink: boolean
+--- - dim: boolean
+--- - conceal: boolean
+--- - overline: boolean
 --- - standout: boolean
 --- - underline: boolean
 --- - undercurl: boolean

runtime/lua/vim/_meta/api_keysets.lua

@@ -306,6 +306,10 @@ error('Cannot require a meta file')
 --- @field italic? boolean
 --- @field reverse? boolean
 --- @field altfont? boolean
+--- @field dim? boolean
+--- @field blink? boolean
+--- @field conceal? boolean
+--- @field overline? boolean
 --- @field nocombine? boolean
 --- @field default? boolean
 --- @field cterm? vim.api.keyset.highlight_cterm
@@ -338,6 +342,10 @@ error('Cannot require a meta file')
 --- @field italic? boolean
 --- @field reverse? boolean
 --- @field altfont? boolean
+--- @field dim? boolean
+--- @field blink? boolean
+--- @field conceal? boolean
+--- @field overline? boolean
 --- @field nocombine? boolean
 
 --- @class vim.api.keyset.keymap

runtime/lua/vim/_meta/vimfn.lua

@@ -10078,6 +10078,10 @@ function vim.fn.synID(lnum, col, trans) end
 --- "strikethrough"  "1" if struckthrough
 --- "altfont"  "1" if alternative font
 --- "nocombine"  "1" if nocombine
+--- "dim"  "1" if half-bright/dimmed
+--- "blink"  "1" if blinking
+--- "conceal"  "1" if concealed
+--- "overline"  "1" if overlined
 ---
 --- Returns an empty string on error.
 ---

src/gen/gen_terminfo.lua

@@ -53,10 +53,13 @@ local wanted_strings = {
   'cursor_up',
   'cursor_right',
   'delete_line',
+  'enter_blink_mode',
   'enter_bold_mode',
   'enter_ca_mode',
+  'enter_dim_mode',
   'enter_italics_mode',
   'enter_reverse_mode',
+  'enter_secure_mode',
   'enter_standout_mode',
   'enter_underline_mode',
   'erase_chars',

src/nvim/api/keysets_defs.h

@@ -179,6 +179,10 @@ typedef struct {
   Boolean italic;
   Boolean reverse;
   Boolean altfont;
+  Boolean dim;
+  Boolean blink;
+  Boolean conceal;
+  Boolean overline;
   Boolean nocombine;
   Boolean default_ DictKey(default);
   DictAs(highlight_cterm) cterm;
@@ -212,6 +216,10 @@ typedef struct {
   Boolean italic;
   Boolean reverse;
   Boolean altfont;
+  Boolean dim;
+  Boolean blink;
+  Boolean conceal;
+  Boolean overline;
   Boolean nocombine;
 } Dict(highlight_cterm);
 

src/nvim/api/vim.c

@@ -152,6 +152,11 @@ DictAs(get_hl_info) nvim_get_hl(Integer ns_id, Dict(get_highlight) *opts, Arena
 ///                - sp: color name or "#RRGGBB"
 ///                - blend: integer between 0 and 100
 ///                - bold: boolean
+///                - altfont: boolean
+///                - blink: boolean
+///                - dim: boolean
+///                - conceal: boolean
+///                - overline: boolean
 ///                - standout: boolean
 ///                - underline: boolean
 ///                - undercurl: boolean

src/nvim/eval.lua

@@ -12158,6 +12158,10 @@ M.funcs = {
       "strikethrough"	"1" if struckthrough
       "altfont"	"1" if alternative font
       "nocombine"	"1" if nocombine
+      "dim"	"1" if half-bright/dimmed
+      "blink"	"1" if blinking
+      "conceal"	"1" if concealed
+      "overline"	"1" if overlined
 
       Returns an empty string on error.
 

src/nvim/eval/funcs.c

@@ -7371,10 +7371,21 @@ static void f_synIDattr(typval_T *argvars, typval_T *rettv, EvalFuncData fptr)
   case 'b':
     if (TOLOWER_ASC(what[1]) == 'g') {  // bg[#]
       p = highlight_color(id, what, modec);
+    } else if (TOLOWER_ASC(what[1]) == 'l') {  // blink
+      p = highlight_has_attr(id, HL_BLINK, modec);
     } else {  // bold
       p = highlight_has_attr(id, HL_BOLD, modec);
     }
     break;
+  case 'c':    // conceal
+    p = highlight_has_attr(id, HL_CONCEALED, modec);
+    break;
+  case 'd':    // dim
+    p = highlight_has_attr(id, HL_DIM, modec);
+    break;
+  case 'o':    // overline
+    p = highlight_has_attr(id, HL_OVERLINE, modec);
+    break;
   case 'f':    // fg[#] or font
     p = highlight_color(id, what, modec);
     break;

src/nvim/highlight.c

@@ -562,11 +562,11 @@ void hl_invalidate_blends(void)
 
 /// Combine HlAttrFlags.
 /// The underline attribute in "prim_ae" overrules the one in "char_ae" if both are present.
-static int16_t hl_combine_ae(int16_t char_ae, int16_t prim_ae)
+static int32_t hl_combine_ae(int32_t char_ae, int32_t prim_ae)
 {
-  int16_t char_ul = char_ae & HL_UNDERLINE_MASK;
+  int32_t char_ul = char_ae & HL_UNDERLINE_MASK;
-  int16_t prim_ul = prim_ae & HL_UNDERLINE_MASK;
+  int32_t prim_ul = prim_ae & HL_UNDERLINE_MASK;
-  int16_t new_ul = prim_ul ? prim_ul : char_ul;
+  int32_t new_ul = prim_ul ? prim_ul : char_ul;
   return (char_ae & ~HL_UNDERLINE_MASK) | (prim_ae & ~HL_UNDERLINE_MASK) | new_ul;
 }
 
@@ -946,6 +946,22 @@ void hlattrs2dict(Dict *hl, Dict *hl_attrs, HlAttrs ae, bool use_rgb, bool short
     PUT_C(*hl_attrs, "altfont", BOOLEAN_OBJ(true));
   }
 
+  if (mask & HL_DIM) {
+    PUT_C(*hl_attrs, "dim", BOOLEAN_OBJ(true));
+  }
+
+  if (mask & HL_BLINK) {
+    PUT_C(*hl_attrs, "blink", BOOLEAN_OBJ(true));
+  }
+
+  if (mask & HL_CONCEALED) {
+    PUT_C(*hl_attrs, "conceal", BOOLEAN_OBJ(true));
+  }
+
+  if (mask & HL_OVERLINE) {
+    PUT_C(*hl_attrs, "overline", BOOLEAN_OBJ(true));
+  }
+
   if (mask & HL_NOCOMBINE) {
     PUT_C(*hl_attrs, "nocombine", BOOLEAN_OBJ(true));
   }
@@ -997,8 +1013,8 @@ HlAttrs dict2hlattrs(Dict(highlight) *dict, bool use_rgb, int *link_id, Error *e
   int32_t ctermbg = -1;
   int32_t sp = -1;
   int blend = -1;
-  int16_t mask = 0;
+  int32_t mask = 0;
-  int16_t cterm_mask = 0;
+  int32_t cterm_mask = 0;
   bool cterm_mask_provided = false;
 
 #define CHECK_FLAG(d, m, name, extra, flag) \
@@ -1020,6 +1036,10 @@ HlAttrs dict2hlattrs(Dict(highlight) *dict, bool use_rgb, int *link_id, Error *e
   CHECK_FLAG(dict, mask, standout, , HL_STANDOUT);
   CHECK_FLAG(dict, mask, strikethrough, , HL_STRIKETHROUGH);
   CHECK_FLAG(dict, mask, altfont, , HL_ALTFONT);
+  CHECK_FLAG(dict, mask, dim, , HL_DIM);
+  CHECK_FLAG(dict, mask, blink, , HL_BLINK);
+  CHECK_FLAG(dict, mask, conceal, , HL_CONCEALED);
+  CHECK_FLAG(dict, mask, overline, , HL_OVERLINE);
   if (use_rgb) {
     CHECK_FLAG(dict, mask, fg_indexed, , HL_FG_INDEXED);
     CHECK_FLAG(dict, mask, bg_indexed, , HL_BG_INDEXED);
@@ -1100,6 +1120,10 @@ HlAttrs dict2hlattrs(Dict(highlight) *dict, bool use_rgb, int *link_id, Error *e
     CHECK_FLAG(cterm, cterm_mask, standout, , HL_STANDOUT);
     CHECK_FLAG(cterm, cterm_mask, strikethrough, , HL_STRIKETHROUGH);
     CHECK_FLAG(cterm, cterm_mask, altfont, , HL_ALTFONT);
+    CHECK_FLAG(cterm, cterm_mask, dim, , HL_DIM);
+    CHECK_FLAG(cterm, cterm_mask, blink, , HL_BLINK);
+    CHECK_FLAG(cterm, cterm_mask, conceal, , HL_CONCEALED);
+    CHECK_FLAG(cterm, cterm_mask, overline, , HL_OVERLINE);
     CHECK_FLAG(cterm, cterm_mask, nocombine, , HL_NOCOMBINE);
   }
 #undef CHECK_FLAG

src/nvim/highlight_defs.h

@@ -25,7 +25,10 @@ typedef enum {
   HL_STANDOUT      = 0x0040,
   HL_STRIKETHROUGH = 0x0080,
   HL_ALTFONT       = 0x0100,
-  // 0x0200 spare
+  HL_DIM           = 0x0200,
+  HL_BLINK         = 0x8000,
+  HL_CONCEALED     = 0x10000,
+  HL_OVERLINE      = 0x20000,
   HL_NOCOMBINE     = 0x0400,
   HL_BG_INDEXED    = 0x0800,
   HL_FG_INDEXED    = 0x1000,
@@ -36,7 +39,7 @@ typedef enum {
 /// Stores a complete highlighting entry, including colors and attributes
 /// for both TUI and GUI.
 typedef struct {
-  int16_t rgb_ae_attr, cterm_ae_attr;  ///< HlAttrFlags
+  int32_t rgb_ae_attr, cterm_ae_attr;  ///< HlAttrFlags
   RgbValue rgb_fg_color, rgb_bg_color, rgb_sp_color;
   int16_t cterm_fg_color, cterm_bg_color;
   int32_t hl_blend;
@@ -175,4 +178,4 @@ typedef struct {
 #define COLOR_ITEM_INITIALIZER { .attr_id = -1, .link_id = -1, .version = -1, \
                                  .is_default = false, .link_global = false }
 
-enum { HLATTRS_DICT_SIZE = 16, };
+enum { HLATTRS_DICT_SIZE = 20, };

src/nvim/highlight_group.c

@@ -77,12 +77,12 @@ static char *(hl_name_table[]) =
 { "bold", "standout", "underline",
   "undercurl", "underdouble", "underdotted", "underdashed",
   "italic", "reverse", "inverse", "strikethrough", "altfont",
-  "nocombine", "NONE" };
+  "dim", "blink", "conceal", "overline", "nocombine", "NONE" };
 static int hl_attr_table[] =
 { HL_BOLD, HL_STANDOUT, HL_UNDERLINE,
   HL_UNDERCURL, HL_UNDERDOUBLE, HL_UNDERDOTTED, HL_UNDERDASHED,
   HL_ITALIC, HL_INVERSE, HL_INVERSE, HL_STRIKETHROUGH, HL_ALTFONT,
-  HL_NOCOMBINE, 0 };
+  HL_DIM, HL_BLINK, HL_CONCEALED, HL_OVERLINE, HL_NOCOMBINE, 0 };
 
 /// Structure that stores information about a highlight group.
 /// The ID of a highlight group is also called group ID.  It is the index in
@@ -1951,10 +1951,10 @@ static void set_hl_attr(int idx)
   HlAttrs at_en = HLATTRS_INIT;
   HlGroup *sgp = hl_table + idx;
 
-  at_en.cterm_ae_attr = (int16_t)sgp->sg_cterm;
+  at_en.cterm_ae_attr = (int32_t)sgp->sg_cterm;
   at_en.cterm_fg_color = (int16_t)sgp->sg_cterm_fg;
   at_en.cterm_bg_color = (int16_t)sgp->sg_cterm_bg;
-  at_en.rgb_ae_attr = (int16_t)sgp->sg_gui;
+  at_en.rgb_ae_attr = (int32_t)sgp->sg_gui;
   // FIXME(tarruda): The "unset value" for rgb is -1, but since hlgroup is
   // initialized with 0 (by garray functions), check for sg_rgb_{f,b}g_name
   // before setting attr_entry->{f,g}g_color to a other than -1

src/nvim/terminal.c

@@ -1405,6 +1405,8 @@ void terminal_get_line_attributes(Terminal *term, win_T *wp, int linenr, int *te
     bool bg_set = vt_bg_idx && vt_bg_idx <= 16 && term->color_set[vt_bg_idx - 1];
 
     int hl_attrs = (cell.attrs.bold ? HL_BOLD : 0)
+                   | (cell.attrs.blink ? HL_BLINK : 0)
+                   | (cell.attrs.conceal ? HL_CONCEALED : 0)
                    | (cell.attrs.italic ? HL_ITALIC : 0)
                    | (cell.attrs.reverse ? HL_INVERSE : 0)
                    | get_underline_hl_flag(cell.attrs)
@@ -1416,10 +1418,10 @@ void terminal_get_line_attributes(Terminal *term, win_T *wp, int linenr, int *te
 
     if (hl_attrs || !fg_default || !bg_default) {
       attr_id = hl_get_term_attr(&(HlAttrs) {
-        .cterm_ae_attr = (int16_t)hl_attrs,
+        .cterm_ae_attr = (int32_t)hl_attrs,
         .cterm_fg_color = vt_fg_idx,
         .cterm_bg_color = vt_bg_idx,
-        .rgb_ae_attr = (int16_t)hl_attrs,
+        .rgb_ae_attr = (int32_t)hl_attrs,
         .rgb_fg_color = vt_fg,
         .rgb_bg_color = vt_bg,
         .rgb_sp_color = -1,

src/nvim/tui/terminfo_builtin.h

@@ -28,10 +28,13 @@ static const TerminfoEntry ansi_terminfo = {
     [kTerm_cursor_up] = "\033[A",
     [kTerm_cursor_right] = "\033[C",
     [kTerm_delete_line] = "\033[M",
+    [kTerm_enter_blink_mode] = "\033[5m",
     [kTerm_enter_bold_mode] = "\033[1m",
     [kTerm_enter_ca_mode] = NULL,
+    [kTerm_enter_dim_mode] = NULL,
     [kTerm_enter_italics_mode] = NULL,
     [kTerm_enter_reverse_mode] = "\033[7m",
+    [kTerm_enter_secure_mode] = "\033[8m",
     [kTerm_enter_standout_mode] = "\033[7m",
     [kTerm_enter_underline_mode] = "\033[4m",
     [kTerm_erase_chars] = "\033[%p1%dX",
@@ -104,10 +107,13 @@ static const TerminfoEntry ghostty_terminfo = {
     [kTerm_cursor_up] = "\033[A",
     [kTerm_cursor_right] = "\033[C",
     [kTerm_delete_line] = "\033[M",
+    [kTerm_enter_blink_mode] = NULL,
     [kTerm_enter_bold_mode] = "\033[1m",
     [kTerm_enter_ca_mode] = "\033[?1049h",
+    [kTerm_enter_dim_mode] = "\033[2m",
     [kTerm_enter_italics_mode] = "\033[3m",
     [kTerm_enter_reverse_mode] = "\033[7m",
+    [kTerm_enter_secure_mode] = "\033[8m",
     [kTerm_enter_standout_mode] = "\033[7m",
     [kTerm_enter_underline_mode] = "\033[4m",
     [kTerm_erase_chars] = "\033[%p1%dX",
@@ -243,10 +249,13 @@ static const TerminfoEntry interix_8colour_terminfo = {
     [kTerm_cursor_up] = "\033[A",
     [kTerm_cursor_right] = "\033[C",
     [kTerm_delete_line] = "\033[M",
+    [kTerm_enter_blink_mode] = NULL,
     [kTerm_enter_bold_mode] = "\033[1m",
     [kTerm_enter_ca_mode] = "\033[s\033[1b",
+    [kTerm_enter_dim_mode] = NULL,
     [kTerm_enter_italics_mode] = NULL,
     [kTerm_enter_reverse_mode] = "\033[7m",
+    [kTerm_enter_secure_mode] = NULL,
     [kTerm_enter_standout_mode] = "\033[7m",
     [kTerm_enter_underline_mode] = "\033[4m",
     [kTerm_erase_chars] = NULL,
@@ -379,10 +388,13 @@ static const TerminfoEntry iterm_256colour_terminfo = {
     [kTerm_cursor_up] = "\033[A",
     [kTerm_cursor_right] = "\033[C",
     [kTerm_delete_line] = "\033[M",
+    [kTerm_enter_blink_mode] = "\033[5m",
     [kTerm_enter_bold_mode] = "\033[1m",
     [kTerm_enter_ca_mode] = "\033[?1049h\033[22;0;0t",
+    [kTerm_enter_dim_mode] = "\033[2m",
     [kTerm_enter_italics_mode] = "\033[3m",
     [kTerm_enter_reverse_mode] = "\033[7m",
+    [kTerm_enter_secure_mode] = NULL,
     [kTerm_enter_standout_mode] = "\033[7m",
     [kTerm_enter_underline_mode] = "\033[4m",
     [kTerm_erase_chars] = NULL,
@@ -479,10 +491,13 @@ static const TerminfoEntry linux_16colour_terminfo = {
     [kTerm_cursor_up] = "\033[A",
     [kTerm_cursor_right] = "\033[C",
     [kTerm_delete_line] = "\033[M",
+    [kTerm_enter_blink_mode] = "\033[5m",
     [kTerm_enter_bold_mode] = "\033[1m",
     [kTerm_enter_ca_mode] = NULL,
+    [kTerm_enter_dim_mode] = "\033[2m",
     [kTerm_enter_italics_mode] = NULL,
     [kTerm_enter_reverse_mode] = "\033[7m",
+    [kTerm_enter_secure_mode] = NULL,
     [kTerm_enter_standout_mode] = "\033[7m",
     [kTerm_enter_underline_mode] = "\033[4m",
     [kTerm_erase_chars] = "\033[%p1%dX",
@@ -575,10 +590,13 @@ static const TerminfoEntry putty_256colour_terminfo = {
     [kTerm_cursor_up] = "\033M",
     [kTerm_cursor_right] = "\033[C",
     [kTerm_delete_line] = "\033[M",
+    [kTerm_enter_blink_mode] = "\033[5m",
     [kTerm_enter_bold_mode] = "\033[1m",
     [kTerm_enter_ca_mode] = "\033[?1049h",
+    [kTerm_enter_dim_mode] = NULL,
     [kTerm_enter_italics_mode] = NULL,
     [kTerm_enter_reverse_mode] = "\033[7m",
+    [kTerm_enter_secure_mode] = NULL,
     [kTerm_enter_standout_mode] = "\033[7m",
     [kTerm_enter_underline_mode] = "\033[4m",
     [kTerm_erase_chars] = "\033[%p1%dX",
@@ -671,10 +689,13 @@ static const TerminfoEntry rxvt_256colour_terminfo = {
     [kTerm_cursor_up] = "\033[A",
     [kTerm_cursor_right] = "\033[C",
     [kTerm_delete_line] = "\033[M",
+    [kTerm_enter_blink_mode] = "\033[5m",
     [kTerm_enter_bold_mode] = "\033[1m",
     [kTerm_enter_ca_mode] = "\0337\033[?47h",
+    [kTerm_enter_dim_mode] = NULL,
     [kTerm_enter_italics_mode] = NULL,
     [kTerm_enter_reverse_mode] = "\033[7m",
+    [kTerm_enter_secure_mode] = NULL,
     [kTerm_enter_standout_mode] = "\033[7m",
     [kTerm_enter_underline_mode] = "\033[4m",
     [kTerm_erase_chars] = NULL,
@@ -791,10 +812,13 @@ static const TerminfoEntry screen_256colour_terminfo = {
     [kTerm_cursor_up] = "\033M",
     [kTerm_cursor_right] = "\033[C",
     [kTerm_delete_line] = "\033[M",
+    [kTerm_enter_blink_mode] = "\033[5m",
     [kTerm_enter_bold_mode] = "\033[1m",
     [kTerm_enter_ca_mode] = "\033[?1049h",
+    [kTerm_enter_dim_mode] = "\033[2m",
     [kTerm_enter_italics_mode] = NULL,
     [kTerm_enter_reverse_mode] = "\033[7m",
+    [kTerm_enter_secure_mode] = NULL,
     [kTerm_enter_standout_mode] = "\033[3m",
     [kTerm_enter_underline_mode] = "\033[4m",
     [kTerm_erase_chars] = NULL,
@@ -879,10 +903,13 @@ static const TerminfoEntry st_256colour_terminfo = {
     [kTerm_cursor_up] = "\033[A",
     [kTerm_cursor_right] = "\033[C",
     [kTerm_delete_line] = "\033[M",
+    [kTerm_enter_blink_mode] = "\033[5m",
     [kTerm_enter_bold_mode] = "\033[1m",
     [kTerm_enter_ca_mode] = "\033[?1049h",
+    [kTerm_enter_dim_mode] = "\033[2m",
     [kTerm_enter_italics_mode] = "\033[3m",
     [kTerm_enter_reverse_mode] = "\033[7m",
+    [kTerm_enter_secure_mode] = "\033[8m",
     [kTerm_enter_standout_mode] = "\033[7m",
     [kTerm_enter_underline_mode] = "\033[4m",
     [kTerm_erase_chars] = "\033[%p1%dX",
@@ -1018,10 +1045,13 @@ static const TerminfoEntry tmux_256colour_terminfo = {
     [kTerm_cursor_up] = "\033M",
     [kTerm_cursor_right] = "\033[C",
     [kTerm_delete_line] = "\033[M",
+    [kTerm_enter_blink_mode] = "\033[5m",
     [kTerm_enter_bold_mode] = "\033[1m",
     [kTerm_enter_ca_mode] = "\033[?1049h",
+    [kTerm_enter_dim_mode] = "\033[2m",
     [kTerm_enter_italics_mode] = "\033[3m",
     [kTerm_enter_reverse_mode] = "\033[7m",
+    [kTerm_enter_secure_mode] = "\033[8m",
     [kTerm_enter_standout_mode] = "\033[7m",
     [kTerm_enter_underline_mode] = "\033[4m",
     [kTerm_erase_chars] = NULL,
@@ -1157,10 +1187,13 @@ static const TerminfoEntry vte_256colour_terminfo = {
     [kTerm_cursor_up] = "\033[A",
     [kTerm_cursor_right] = "\033[C",
     [kTerm_delete_line] = "\033[M",
+    [kTerm_enter_blink_mode] = "\033[5m",
     [kTerm_enter_bold_mode] = "\033[1m",
     [kTerm_enter_ca_mode] = "\033[?1049h\033[22;0;0t",
+    [kTerm_enter_dim_mode] = "\033[2m",
     [kTerm_enter_italics_mode] = "\033[3m",
     [kTerm_enter_reverse_mode] = "\033[7m",
+    [kTerm_enter_secure_mode] = "\033[8m",
     [kTerm_enter_standout_mode] = "\033[7m",
     [kTerm_enter_underline_mode] = "\033[4m",
     [kTerm_erase_chars] = "\033[%p1%dX",
@@ -1296,10 +1329,13 @@ static const TerminfoEntry xterm_256colour_terminfo = {
     [kTerm_cursor_up] = "\033[A",
     [kTerm_cursor_right] = "\033[C",
     [kTerm_delete_line] = "\033[M",
+    [kTerm_enter_blink_mode] = "\033[5m",
     [kTerm_enter_bold_mode] = "\033[1m",
     [kTerm_enter_ca_mode] = "\033[?1049h\033[22;0;0t",
+    [kTerm_enter_dim_mode] = "\033[2m",
     [kTerm_enter_italics_mode] = "\033[3m",
     [kTerm_enter_reverse_mode] = "\033[7m",
+    [kTerm_enter_secure_mode] = "\033[8m",
     [kTerm_enter_standout_mode] = "\033[7m",
     [kTerm_enter_underline_mode] = "\033[4m",
     [kTerm_erase_chars] = "\033[%p1%dX",
@@ -1435,10 +1471,13 @@ static const TerminfoEntry cygwin_terminfo = {
     [kTerm_cursor_up] = "\033[A",
     [kTerm_cursor_right] = "\033[C",
     [kTerm_delete_line] = "\033[M",
+    [kTerm_enter_blink_mode] = NULL,
     [kTerm_enter_bold_mode] = "\033[1m",
     [kTerm_enter_ca_mode] = "\0337\033[?47h",
+    [kTerm_enter_dim_mode] = NULL,
     [kTerm_enter_italics_mode] = NULL,
     [kTerm_enter_reverse_mode] = "\033[7m",
+    [kTerm_enter_secure_mode] = "\033[8m",
     [kTerm_enter_standout_mode] = "\033[7m",
     [kTerm_enter_underline_mode] = "\033[4m",
     [kTerm_erase_chars] = NULL,
@@ -1531,10 +1570,13 @@ static const TerminfoEntry win32con_terminfo = {
     [kTerm_cursor_up] = "\033[A",
     [kTerm_cursor_right] = "\033[C",
     [kTerm_delete_line] = NULL,
+    [kTerm_enter_blink_mode] = NULL,
     [kTerm_enter_bold_mode] = "\033[1m",
     [kTerm_enter_ca_mode] = "\0337\033[?47h",
+    [kTerm_enter_dim_mode] = NULL,
     [kTerm_enter_italics_mode] = NULL,
     [kTerm_enter_reverse_mode] = "\033[7m",
+    [kTerm_enter_secure_mode] = NULL,
     [kTerm_enter_standout_mode] = "\033[7m",
     [kTerm_enter_underline_mode] = NULL,
     [kTerm_erase_chars] = NULL,
@@ -1651,10 +1693,13 @@ static const TerminfoEntry conemu_terminfo = {
     [kTerm_cursor_up] = "\033[A",
     [kTerm_cursor_right] = "\033[C",
     [kTerm_delete_line] = "\033[M",
+    [kTerm_enter_blink_mode] = NULL,
     [kTerm_enter_bold_mode] = "\033[1m",
     [kTerm_enter_ca_mode] = "\033[?1049h",
+    [kTerm_enter_dim_mode] = NULL,
     [kTerm_enter_italics_mode] = "\033[3m",
     [kTerm_enter_reverse_mode] = "\033[7m",
+    [kTerm_enter_secure_mode] = NULL,
     [kTerm_enter_standout_mode] = "\033[7m",
     [kTerm_enter_underline_mode] = "\033[4m",
     [kTerm_erase_chars] = "\033[%p1%dX",
@@ -1772,10 +1817,13 @@ static const TerminfoEntry vtpcon_terminfo = {
     [kTerm_cursor_up] = "\033[A",
     [kTerm_cursor_right] = "\033[C",
     [kTerm_delete_line] = "\033[M",
+    [kTerm_enter_blink_mode] = NULL,
     [kTerm_enter_bold_mode] = "\033[1m",
     [kTerm_enter_ca_mode] = "\033[?1049h",
+    [kTerm_enter_dim_mode] = NULL,
     [kTerm_enter_italics_mode] = "\033[3m",
     [kTerm_enter_reverse_mode] = "\033[7m",
+    [kTerm_enter_secure_mode] = NULL,
     [kTerm_enter_standout_mode] = "\033[7m",
     [kTerm_enter_underline_mode] = "\033[4m",
     [kTerm_erase_chars] = "\033[%p1%dX",
@@ -1886,10 +1934,13 @@ static const TerminfoEntry vtpcon_terminfo = {
   X(cursor_up) \
   X(cursor_right) \
   X(delete_line) \
+  X(enter_blink_mode) \
   X(enter_bold_mode) \
   X(enter_ca_mode) \
+  X(enter_dim_mode) \
   X(enter_italics_mode) \
   X(enter_reverse_mode) \
+  X(enter_secure_mode) \
   X(enter_standout_mode) \
   X(enter_underline_mode) \
   X(erase_chars) \

src/nvim/tui/terminfo_enum_defs.h

@@ -17,10 +17,13 @@ typedef enum {
   kTerm_cursor_up,
   kTerm_cursor_right,
   kTerm_delete_line,
+  kTerm_enter_blink_mode,
   kTerm_enter_bold_mode,
   kTerm_enter_ca_mode,
+  kTerm_enter_dim_mode,
   kTerm_enter_italics_mode,
   kTerm_enter_reverse_mode,
+  kTerm_enter_secure_mode,
   kTerm_enter_standout_mode,
   kTerm_enter_underline_mode,
   kTerm_erase_chars,

src/nvim/tui/tui.c

@@ -752,6 +752,10 @@ static void update_attrs(TUIData *tui, int attr_id)
   bool standout = attr & HL_STANDOUT;
   bool strikethrough = attr & HL_STRIKETHROUGH;
   bool altfont = attr & HL_ALTFONT;
+  bool dim = attr & HL_DIM;
+  bool blink = attr & HL_BLINK;
+  bool conceal = attr & HL_CONCEALED;
+  bool overline = attr & HL_OVERLINE;
 
   bool underline;
   bool undercurl;
@@ -777,13 +781,13 @@ static void update_attrs(TUIData *tui, int attr_id)
                            || underdouble || underdotted || underdashed;
 
   if (tui->ti.defs[kTerm_set_attributes] != NULL) {
-    if (bold || reverse || underline || standout) {
+    if (bold || dim || blink || reverse || underline || standout) {
       TPVAR params[9] = { 0 };
       params[0].num = standout;
       params[1].num = underline;
       params[2].num = reverse;
-      params[3].num = 0;   // blink
+      params[3].num = blink;
-      params[4].num = 0;   // dim
+      params[4].num = dim;
       params[5].num = bold;
       params[6].num = 0;   // blank
       params[7].num = 0;   // protect
@@ -808,6 +812,12 @@ static void update_attrs(TUIData *tui, int attr_id)
     if (reverse) {
       terminfo_out(tui, kTerm_enter_reverse_mode);
     }
+    if (dim) {
+      terminfo_out(tui, kTerm_enter_dim_mode);
+    }
+    if (blink) {
+      terminfo_out(tui, kTerm_enter_blink_mode);
+    }
   }
   if (italic) {
     terminfo_out(tui, kTerm_enter_italics_mode);
@@ -818,6 +828,12 @@ static void update_attrs(TUIData *tui, int attr_id)
   if (strikethrough) {
     terminfo_out(tui, kTerm_enter_strikethrough_mode);
   }
+  if (conceal) {
+    terminfo_out(tui, kTerm_enter_secure_mode);
+  }
+  if (overline) {
+    out(tui, S_LEN("\x1b[53m"));
+  }
   if (tui->ti.defs[kTerm_set_underline_style]) {
     if (undercurl) {
       terminfo_print_num1(tui, kTerm_set_underline_style, 3);
@@ -898,14 +914,14 @@ static void update_attrs(TUIData *tui, int attr_id)
   }
 
   tui->default_attr = fg == -1 && bg == -1
-                      && !bold && !italic && !has_any_underline && !reverse && !standout
+                      && !bold && !dim && !blink && !conceal && !overline && !italic
-                      && !strikethrough;
+                      && !has_any_underline && !reverse && !standout && !strikethrough;
 
   // Non-BCE terminals can't clear with non-default background color. Some BCE
   // terminals don't support attributes either, so don't rely on it. But assume
   // italic and bold has no effect if there is no text.
-  tui->can_clear_attr = !reverse && !standout && !has_any_underline
+  tui->can_clear_attr = !reverse && !standout && !dim && !blink && !conceal && !overline
-                        && !strikethrough && (tui->bce || bg == -1);
+                        && !has_any_underline && !strikethrough && (tui->bce || bg == -1);
 }
 
 static void final_column_wrap(TUIData *tui)

test/functional/api/highlight_spec.lua

@@ -46,11 +46,19 @@ describe('API: set highlight', function()
     underdashed = true,
     strikethrough = true,
     altfont = true,
+    dim = true,
+    blink = true,
+    conceal = true,
+    overline = true,
     cterm = {
       italic = true,
       reverse = true,
       strikethrough = true,
       altfont = true,
+      dim = true,
+      blink = true,
+      conceal = true,
+      overline = true,
       nocombine = true,
     },
   }
@@ -63,6 +71,10 @@ describe('API: set highlight', function()
     underdashed = true,
     strikethrough = true,
     altfont = true,
+    dim = true,
+    blink = true,
+    conceal = true,
+    overline = true,
   }
   local highlight3_result_cterm = {
     ctermbg = highlight_color.ctermbg,
@@ -71,6 +83,10 @@ describe('API: set highlight', function()
     reverse = true,
     strikethrough = true,
     altfont = true,
+    dim = true,
+    blink = true,
+    conceal = true,
+    overline = true,
     nocombine = true,
   }
 
@@ -172,7 +188,7 @@ describe('API: set highlight', function()
 
     api.nvim_set_hl(0, 'Test_hl2', highlight3_config)
     eq(
-      'Test_hl2       xxx cterm=italic,reverse,strikethrough,altfont,nocombine ctermfg=8 ctermbg=15 gui=bold,underdashed,italic,reverse,strikethrough,altfont guifg=#ff0000 guibg=#0032aa',
+      'Test_hl2       xxx cterm=italic,reverse,strikethrough,altfont,dim,blink,conceal,overline,nocombine ctermfg=8 ctermbg=15 gui=bold,underdashed,italic,reverse,strikethrough,altfont,dim,blink,conceal,overline guifg=#ff0000 guibg=#0032aa',
       exec_capture('highlight Test_hl2')
     )
 
@@ -272,11 +288,19 @@ describe('API: get highlight', function()
     underdashed = true,
     strikethrough = true,
     altfont = true,
+    dim = true,
+    blink = true,
+    conceal = true,
+    overline = true,
     cterm = {
       italic = true,
       reverse = true,
       strikethrough = true,
       altfont = true,
+      dim = true,
+      blink = true,
+      conceal = true,
+      overline = true,
       nocombine = true,
     },
   }
@@ -291,12 +315,20 @@ describe('API: get highlight', function()
     underdashed = true,
     strikethrough = true,
     altfont = true,
+    dim = true,
+    blink = true,
+    conceal = true,
+    overline = true,
     cterm = {
       italic = true,
       nocombine = true,
       reverse = true,
       strikethrough = true,
       altfont = true,
+      dim = true,
+      blink = true,
+      conceal = true,
+      overline = true,
     },
   }
 
@@ -438,15 +470,21 @@ describe('API: get highlight', function()
     )
 
     -- Test all highlight properties.
-    command('hi NewHighlight gui=underline,bold,italic,reverse,strikethrough,altfont,nocombine')
+    command(
+      'hi NewHighlight gui=underline,bold,italic,reverse,strikethrough,altfont,dim,blink,conceal,overline,nocombine'
+    )
     eq({
       fg = 16711680,
       bg = 16776960,
       sp = 255,
       altfont = true,
+      blink = true,
       bold = true,
+      conceal = true,
+      dim = true,
       italic = true,
       nocombine = true,
+      overline = true,
       reverse = true,
       strikethrough = true,
       underline = true,