fix(float): apply 'winblend' to title/footer highlight (#25999)

src/nvim/drawscreen.c

@@ -725,6 +725,7 @@ static void win_redr_bordertext(win_T *wp, VirtText vt, int col)
     if (text == NULL) {
       break;
     }
+    attr = hl_apply_winblend(wp, attr);
     col += grid_line_puts(col, text, -1, attr);
   }
 }

src/nvim/highlight.c

@@ -323,6 +323,23 @@ int hl_get_ui_attr(int ns_id, int idx, int final_id, bool optional)
                                    .id1 = idx, .id2 = final_id });
 }
 
+/// Apply 'winblend' to highlight attributes.
+///
+/// @param wp    The window to get 'winblend' value from.
+/// @param attr  The original attribute code.
+///
+/// @return      The attribute code with 'winblend' applied.
+int hl_apply_winblend(win_T *wp, int attr)
+{
+  HlEntry entry = attr_entry(attr);
+  // if blend= attribute is not set, 'winblend' value overrides it.
+  if (entry.attr.hl_blend == -1 && wp->w_p_winbl > 0) {
+    entry.attr.hl_blend = (int)wp->w_p_winbl;
+    attr = get_attr_entry(entry);
+  }
+  return attr;
+}
+
 void update_window_hl(win_T *wp, bool invalid)
 {
   int ns_id = wp->w_ns_hl;
@@ -358,13 +375,8 @@ void update_window_hl(win_T *wp, bool invalid)
     wp->w_hl_attr_normal = float_win ? HL_ATTR(HLF_NFLOAT) : 0;
   }
 
-  // if blend= attribute is not set, 'winblend' value overrides it.
-  if (wp->w_floating && wp->w_p_winbl > 0) {
-    HlEntry entry = attr_entry(wp->w_hl_attr_normal);
-    if (entry.attr.hl_blend == -1) {
-      entry.attr.hl_blend = (int)wp->w_p_winbl;
-      wp->w_hl_attr_normal = get_attr_entry(entry);
-    }
+  if (wp->w_floating) {
+    wp->w_hl_attr_normal = hl_apply_winblend(wp, wp->w_hl_attr_normal);
   }
 
   wp->w_float_config.shadow = false;
@@ -375,13 +387,8 @@ void update_window_hl(win_T *wp, bool invalid)
         attr = hl_get_ui_attr(ns_id, HLF_BORDER,
                               wp->w_float_config.border_hl_ids[i], false);
       }
-      HlAttrs a = syn_attr2entry(attr);
-      if (a.hl_blend == -1 && wp->w_p_winbl > 0) {
-        HlEntry entry = attr_entry(attr);
-        a.hl_blend = entry.attr.hl_blend = (int)wp->w_p_winbl;
-        attr = get_attr_entry(entry);
-      }
-      if (a.hl_blend > 0) {
+      attr = hl_apply_winblend(wp, attr);
+      if (syn_attr2entry(attr).hl_blend > 0) {
         wp->w_float_config.shadow = true;
       }
       wp->w_float_config.border_attr[i] = attr;
@@ -400,13 +407,8 @@ void update_window_hl(win_T *wp, bool invalid)
     wp->w_hl_attr_normalnc = hl_def[HLF_INACTIVE];
   }
 
-  // if blend= attribute is not set, 'winblend' value overrides it.
-  if (wp->w_floating && wp->w_p_winbl > 0) {
-    HlEntry entry = attr_entry(wp->w_hl_attr_normalnc);
-    if (entry.attr.hl_blend == -1) {
-      entry.attr.hl_blend = (int)wp->w_p_winbl;
-      wp->w_hl_attr_normalnc = get_attr_entry(entry);
-    }
+  if (wp->w_floating) {
+    wp->w_hl_attr_normalnc = hl_apply_winblend(wp, wp->w_hl_attr_normalnc);
   }
 }
 

test/functional/ui/float_spec.lua

@@ -9198,6 +9198,9 @@ describe('float window', function()
         [20] = {background = Screen.colors.White, foreground = Screen.colors.Gray0};
         [21] = {background = Screen.colors.White, bold = true, foreground = tonumber('0x00007f')};
         [22] = {background = Screen.colors.Gray90, foreground = Screen.colors.Gray0};
+        [23] = {blend = 100, bold = true, foreground = Screen.colors.Magenta};
+        [24] = {foreground = tonumber('0x7f007f'), bold = true, background = Screen.colors.White};
+        [25] = {foreground = tonumber('0x7f007f'), bold = true, background = Screen.colors.Grey90};
       })
       insert([[
         Lorem ipsum dolor sit amet, consectetur
@@ -9483,8 +9486,8 @@ describe('float window', function()
         ]])
       end
 
-      -- Check that 'winblend' applies to border
-      meths.win_set_config(win, {border='single'})
+      -- Check that 'winblend' applies to border/title/footer
+      meths.win_set_config(win, {border='single', title='Title', footer='Footer'})
       meths.set_option_value('winblend', 100, {win=win.id})
       meths.set_option_value("cursorline", true, {win=0})
       command('hi clear VertSplit')
@@ -9513,21 +9516,21 @@ describe('float window', function()
         ## grid 3
                                                             |
         ## grid 4
-          {17:┌───────────────┐}|
+          {17:┌}{23:Title}{17:──────────┐}|
           {17:│}{11:popup    text}{18:  }{17:│}|
           {17:│}{19:~              }{17:│}|
           {17:│}{19:~              }{17:│}|
-          {17:└───────────────┘}|
+          {17:└}{23:Footer}{17:─────────┘}|
         ]], float_pos={[4] = {{id = 1001}, "NW", 1, 2, 5, true}}}
       else
         screen:expect([[
           Ut enim ad minim veniam, quis nostrud             |
           exercitation ullamco laboris nisi ut aliquip ex   |
-          ea co{20:┌───────────────┐}Duis aute irure dolor in    |
+          ea co{20:┌}{24:Title}{20:──────────┐}Duis aute irure dolor in    |
           repre{20:│}{5:popup}{6:it i}{5:text}{20:lu│}tate velit esse cillum      |
           dolor{20:│}{21:~}{20:eu fugiat null│} pariatur. Excepteur sint   |
           occae{20:│}{21:~}{20:t cupidatat no│} proident, sunt in culpa    |
-          {16:^qui o}{22:└───────────────┘}{16:ollit anim id est           }|
+          {16:^qui o}{22:└}{25:Footer}{22:─────────┘}{16:ollit anim id est           }|
           laborum.                                          |
                                                             |
         ]])