feat(highlight): support color names for cterm

src/nvim/highlight.c

@@ -821,27 +821,27 @@ HlAttrs dict2hlattrs(Dict(highlight) *dict, bool use_rgb, int *link_id, Error *e
   CHECK_FLAG(dict, mask, global, , HL_GLOBAL);
 
   if (HAS_KEY(dict->fg)) {
-    fg = object_to_color(dict->fg, "fg", err);
+    fg = object_to_color(dict->fg, "fg", true, err);
   } else if (HAS_KEY(dict->foreground)) {
-    fg = object_to_color(dict->foreground, "foreground", err);
+    fg = object_to_color(dict->foreground, "foreground", true, err);
   }
   if (ERROR_SET(err)) {
     return hlattrs;
   }
 
   if (HAS_KEY(dict->bg)) {
-    bg = object_to_color(dict->bg, "bg", err);
+    bg = object_to_color(dict->bg, "bg", true, err);
   } else if (HAS_KEY(dict->background)) {
-    bg = object_to_color(dict->background, "background", err);
+    bg = object_to_color(dict->background, "background", true, err);
   }
   if (ERROR_SET(err)) {
     return hlattrs;
   }
 
   if (HAS_KEY(dict->sp)) {
-    sp = object_to_color(dict->sp, "sp", err);
+    sp = object_to_color(dict->sp, "sp", true, err);
   } else if (HAS_KEY(dict->special)) {
-    sp = object_to_color(dict->special, "special", err);
+    sp = object_to_color(dict->special, "special", true, err);
   }
   if (ERROR_SET(err)) {
     return hlattrs;
@@ -882,14 +882,14 @@ HlAttrs dict2hlattrs(Dict(highlight) *dict, bool use_rgb, int *link_id, Error *e
 #undef CHECK_FLAG
 
   if (HAS_KEY(dict->ctermfg)) {
-    ctermfg = object_to_color(dict->ctermfg, "ctermfg", err);
+    ctermfg = object_to_color(dict->ctermfg, "ctermfg", false, err);
     if (ERROR_SET(err)) {
       return hlattrs;
     }
   }
 
   if (HAS_KEY(dict->ctermbg)) {
-    ctermbg = object_to_color(dict->ctermbg, "ctermbg", err);
+    ctermbg = object_to_color(dict->ctermbg, "ctermbg", false, err);
     if (ERROR_SET(err)) {
       return hlattrs;
     }
@@ -916,14 +916,25 @@ HlAttrs dict2hlattrs(Dict(highlight) *dict, bool use_rgb, int *link_id, Error *e
   return hlattrs;
 }
 
-int object_to_color(Object val, char *key, Error *err)
+int object_to_color(Object val, char *key, bool rgb, Error *err)
 {
   if (val.type == kObjectTypeInteger) {
     return (int)val.data.integer;
   } else if (val.type == kObjectTypeString) {
     String str = val.data.string;
     // TODO(bfredl): be more fancy with "bg", "fg" etc
-    return str.size ? name_to_color(str.data) : 0;
+    int color;
+    if (!str.size) {
+      color = 0;
+    } else if (rgb) {
+      color = name_to_color(str.data);
+    } else {
+      color = name_to_ctermcolor(str.data);
+    }
+    if (color < 0) {
+      api_set_error(err, kErrorTypeValidation, "'%s' is not a valid color", str.data);
+    }
+    return color;
   } else {
     api_set_error(err, kErrorTypeValidation, "'%s' must be string or integer", key);
     return 0;

src/nvim/syntax.c

@@ -8859,6 +8859,22 @@ RgbValue name_to_color(const char *name)
   return -1;
 }
 
+int name_to_ctermcolor(const char *name)
+{
+  int i;
+  int off = TOUPPER_ASC(*name);
+  for (i = ARRAY_SIZE(color_names); --i >= 0;) {
+    if (off == color_names[i][0]
+        && STRICMP(name+1, color_names[i]+1) == 0) {
+      break;
+    }
+  }
+  if (i < 0) {
+    return -1;
+  }
+  TriState bold = kNone;
+  return lookup_color(i, false, &bold);
+}
 
 /**************************************
 *  End of Highlighting stuff          *

test/functional/api/highlight_spec.lua

@@ -290,6 +290,10 @@ describe("API: set highlight", function()
     eq('Test_hl3       xxx ctermfg=12 ctermbg=9',
       exec_capture('highlight Test_hl3'))
 
+    meths.set_hl(0, 'Test_hl3', { ctermbg = 'red' , ctermfg = 'blue'})
+    eq('Test_hl3       xxx ctermfg=12 ctermbg=9',
+      exec_capture('highlight Test_hl3'))
+
     meths.set_hl(0, 'Test_hl3', { ctermbg = 9 })
     eq('Test_hl3       xxx ctermbg=9',
       exec_capture('highlight Test_hl3'))
@@ -297,5 +301,18 @@ describe("API: set highlight", function()
     meths.set_hl(0, 'Test_hl3', {})
     eq('Test_hl3       xxx cleared',
       exec_capture('highlight Test_hl3'))
+
+    eq("'redd' is not a valid color",
+      pcall_err(meths.set_hl, 0, 'Test_hl3', {fg='redd'}))
+
+    eq("'bleu' is not a valid color",
+      pcall_err(meths.set_hl, 0, 'Test_hl3', {ctermfg='bleu'}))
+
+    meths.set_hl(0, 'Test_hl3', {fg='#FF00FF'})
+    eq('Test_hl3       xxx guifg=#FF00FF',
+      exec_capture('highlight Test_hl3'))
+
+    eq("'#FF00FF' is not a valid color",
+      pcall_err(meths.set_hl, 0, 'Test_hl3', {ctermfg='#FF00FF'}))
   end)
 end)