'termguicolors' #4690

TODO: Only works at startup (i.e., in the user's init.vim/vimrc/--cmd),
      but it should probably work at any time.

---

patch 7.4.1799
Problem:    'guicolors' is a confusing option name.
Solution:   Use 'termguicolors' instead. (Hirohito Higashi)
https://github.com/vim/vim/commit/61be73bb0f965a895bfb064ea3e55476ac175162

patch 7.4.1806
Problem:    'termguicolors' option missing from the options window.
Solution:   Add the entry.
https://github.com/vim/vim/commit/8e3d1b6326c103cc92f8d07b1161ee5172acf201

patch 7.4.1808
Problem:    Using wrong feature name to check for 'termguicolors'.
Solution:   Use the right feature name. (Ken Takata)
https://github.com/vim/vim/commit/8a24b794b89916c8074892e7b25121a21f1fa9c9

patch 7.4.1809
Problem:    Using wrong short option name for 'termguicolors'.
Solution:   Use the option name.
https://github.com/vim/vim/commit/868cfc19bb079a16ca58884b551486566f35419b

10 files changed, 49 insertions, 25 deletions

diff --git a/man/nvim.1 b/man/nvim.1
index 7e8cd5b809..2fa3ab8ff5 100644
--- a/man/nvim.1
+++ b/man/nvim.1
@@ -391,9 +391,6 @@ See
 in the
 .Xr tmux 1
 manual page for more information.
-.It Ev NVIM_TUI_ENABLE_TRUE_COLOR
-If defined, assume the host terminal supports 24 bit colors.
-Has no effect in GUIs.
 .El
 .Sh FILES
 .Bl -tag -width "~/.config/nvim/init.vim"
diff --git a/runtime/doc/options.txt b/runtime/doc/options.txt
index 84fc2ecfc1..fedacfaea4 100644
--- a/runtime/doc/options.txt
+++ b/runtime/doc/options.txt
@@ -6420,6 +6420,14 @@ A jump table for the options with a short description can be found at |Q_op|.
 					*'termencoding'* *'tenc'*
 'termencoding' 'tenc'	Removed. |vim-differences| {Nvim}
 
+						*'termguicolors'* *'tgc'*
+'termguicolors' 'tgc'	boolean (default off)
+			global
+	When on, uses |highlight-guifg| and |highlight-guibg| attributes in
+	the terminal (thus using 24-bit color). Requires a ISO-8613-3
+	compatible terminal.
+	Must be set at startup (in your |init.vim| or |--cmd|).
+
 						*'terse'* *'noterse'*
 'terse'			boolean	(default off)
 			global
diff --git a/runtime/doc/various.txt b/runtime/doc/various.txt
index 3a2b8115db..af4224993f 100644
--- a/runtime/doc/various.txt
+++ b/runtime/doc/various.txt
@@ -371,6 +371,7 @@ N  *+tablineat*		'tabline' option recognizing %@Func@ items.
 N  *+tag_binary*	binary searching in tags file |tag-binary-search|
 N  *+tag_old_static*	old method for static tags |tag-old-static|
 m  *+tag_any_white*	any white space allowed in tags file |tag-any-white|
+B  *+termguicolors*	24-bit color in xterm-compatible terminals support
    *+terminfo*		uses |terminfo| instead of termcap
 N  *+termresponse*	support for |t_RV| and |v:termresponse|
 N  *+textobjects*	|text-objects| selection
diff --git a/runtime/optwin.vim b/runtime/optwin.vim
index 7050436aab..07dcd31b1b 100644
--- a/runtime/optwin.vim
+++ b/runtime/optwin.vim
@@ -410,6 +410,10 @@ call append("$", "highlight\twhich highlighting to use for various occasions")
 call <SID>OptionG("hl", &hl)
 call append("$", "hlsearch\thighlight all matches for the last used search pattern")
 call <SID>BinOptionG("hls", &hls)
+if has("termguicolors")
+  call append("$", "termguicolors\tuse GUI colors for the terminal")
+  call <SID>BinOptionG("tgc", &tgc)
+endif
 if has("syntax")
   call append("$", "cursorcolumn\thighlight the screen column of the cursor")
   call append("$", "\t(local to window)")
diff --git a/runtime/syntax/dircolors.vim b/runtime/syntax/dircolors.vim
index c94d720644..1b598c39b5 100644
--- a/runtime/syntax/dircolors.vim
+++ b/runtime/syntax/dircolors.vim
@@ -44,24 +44,24 @@ highlight default link dircolorsExtension Identifier
 highlight default link dircolorsEscape    Special
 
 function! s:set_guicolors() abort
-    let s:guicolors = {}
-
-    let s:guicolors[0]  = "Black"
-    let s:guicolors[1]  = "DarkRed"
-    let s:guicolors[2]  = "DarkGreen"
-    let s:guicolors[3]  = "DarkYellow"
-    let s:guicolors[4]  = "DarkBlue"
-    let s:guicolors[5]  = "DarkMagenta"
-    let s:guicolors[6]  = "DarkCyan"
-    let s:guicolors[7]  = "Gray"
-    let s:guicolors[8]  = "DarkGray"
-    let s:guicolors[9]  = "Red"
-    let s:guicolors[10] = "Green"
-    let s:guicolors[11] = "Yellow"
-    let s:guicolors[12] = "Blue"
-    let s:guicolors[13] = "Magenta"
-    let s:guicolors[14] = "Cyan"
-    let s:guicolors[15] = "White"
+    let s:termguicolors = {}
+
+    let s:termguicolors[0]  = "Black"
+    let s:termguicolors[1]  = "DarkRed"
+    let s:termguicolors[2]  = "DarkGreen"
+    let s:termguicolors[3]  = "DarkYellow"
+    let s:termguicolors[4]  = "DarkBlue"
+    let s:termguicolors[5]  = "DarkMagenta"
+    let s:termguicolors[6]  = "DarkCyan"
+    let s:termguicolors[7]  = "Gray"
+    let s:termguicolors[8]  = "DarkGray"
+    let s:termguicolors[9]  = "Red"
+    let s:termguicolors[10] = "Green"
+    let s:termguicolors[11] = "Yellow"
+    let s:termguicolors[12] = "Blue"
+    let s:termguicolors[13] = "Magenta"
+    let s:termguicolors[14] = "Cyan"
+    let s:termguicolors[15] = "White"
 
     let xterm_palette = ["00", "5f", "87", "af", "d7", "ff"]
 
@@ -70,7 +70,7 @@ function! s:set_guicolors() abort
     for r in xterm_palette
         for g in xterm_palette
             for b in xterm_palette
-                let s:guicolors[cur_col] = '#' . r . g . b
+                let s:termguicolors[cur_col] = '#' . r . g . b
                 let cur_col += 1
             endfor
         endfor
@@ -78,14 +78,14 @@ function! s:set_guicolors() abort
 
     for i in range(24)
         let g = i * 0xa + 8
-        let s:guicolors[i + 232] = '#' . g . g . g
+        let s:termguicolors[i + 232] = '#' . g . g . g
     endfor
 endfunction
 
 function! s:get_hi_str(color, place) abort
     if a:color >= 0 && a:color <= 255
         if has('gui_running')
-            return ' gui' . a:place . '=' . s:guicolors[a:color]
+            return ' gui' . a:place . '=' . s:termguicolors[a:color]
         elseif a:color <= 7 || &t_Co == 256 || &t_Co == 88
             return ' cterm' . a:place . '=' . a:color
         endif
diff --git a/src/nvim/eval.c b/src/nvim/eval.c
index 6e9f89bbb5..8c8881b398 100644
--- a/src/nvim/eval.c
+++ b/src/nvim/eval.c
@@ -10684,6 +10684,7 @@ static void f_has(typval_T *argvars, typval_T *rettv)
     "tablineat",
     "tag_binary",
     "tag_old_static",
+    "termguicolors",
     "termresponse",
     "textobjects",
     "title",
diff --git a/src/nvim/option_defs.h b/src/nvim/option_defs.h
index 87a9a7398c..904e97f8ca 100644
--- a/src/nvim/option_defs.h
+++ b/src/nvim/option_defs.h
@@ -619,6 +619,7 @@ EXTERN long p_titlelen;         ///< 'titlelen'
 EXTERN char_u *p_titleold;      ///< 'titleold'
 EXTERN char_u *p_titlestring;   ///< 'titlestring'
 EXTERN char_u *p_tsr;           ///< 'thesaurus'
+EXTERN bool p_tgc;              ///< 'termguicolors'
 EXTERN int p_ttimeout;          ///< 'ttimeout'
 EXTERN long p_ttm;              ///< 'ttimeoutlen'
 EXTERN char_u *p_udir;          ///< 'undodir'
diff --git a/src/nvim/options.lua b/src/nvim/options.lua
index a743e8c605..218e34f595 100644
--- a/src/nvim/options.lua
+++ b/src/nvim/options.lua
@@ -2383,6 +2383,14 @@ return {
       defaults={if_true={vi=""}}
     },
     {
+      full_name='termguicolors', abbreviation='tgc',
+      type='bool', scope={'global'},
+      vi_def=false,
+      redraw={'everything'},
+      varname='p_tgc',
+      defaults={if_true={vi=false}}
+    },
+    {
       full_name='terse',
       type='bool', scope={'global'},
       vi_def=true,
diff --git a/src/nvim/tui/tui.c b/src/nvim/tui/tui.c
index e1c0407b27..202c5666a1 100644
--- a/src/nvim/tui/tui.c
+++ b/src/nvim/tui/tui.c
@@ -81,7 +81,7 @@ UI *tui_start(void)
 {
   UI *ui = xcalloc(1, sizeof(UI));
   ui->stop = tui_stop;
-  ui->rgb = os_getenv("NVIM_TUI_ENABLE_TRUE_COLOR") != NULL;
+  ui->rgb = p_tgc;
   ui->resize = tui_resize;
   ui->clear = tui_clear;
   ui->eol_clear = tui_eol_clear;
diff --git a/src/nvim/version.c b/src/nvim/version.c
index 81137ff1c6..00f8c28b5e 100644
--- a/src/nvim/version.c
+++ b/src/nvim/version.c
@@ -69,6 +69,10 @@ static char *features[] = {
 
 // clang-format off
 static int included_patches[] = {
+  1809,
+  1808,
+  1806,
+  1799,
   1757,
   1755,
   1753,