Merge pull request #14065 from bfredl/overlaymode

more virt_text display options

5 files changed, 290 insertions, 98 deletions

diff --git a/src/nvim/api/buffer.c b/src/nvim/api/buffer.c
index 2c2e8a024f..66c4454f7b 100644
--- a/src/nvim/api/buffer.c
+++ b/src/nvim/api/buffer.c
@@ -1430,6 +1430,18 @@ Array nvim_buf_get_extmarks(Buffer buffer, Integer ns_id,
 ///                 - "eol": right after eol character (default)
 ///                 - "overlay": display over the specified column, without
 ///                              shifting the underlying text.
+///               - virt_text_hide : hide the virtual text when the background
+///                                  text is selected or hidden due to
+///                                  horizontal scroll 'nowrap'
+///               - hl_mode : control how highlights are combined with the
+///                           highlights of the text. Currently only affects
+///                           virt_text highlights, but might affect `hl_group`
+///                           in later versions.
+///                 - "replace": only show the virt_text color. This is the
+///                              default
+///                 - "combine": combine with background text color
+///                 - "blend": blend with background text color.
+///
 ///               - ephemeral : for use with |nvim_set_decoration_provider|
 ///                   callbacks. The mark will only be used for the current
 ///                   redraw cycle, and not be permantently stored in the
@@ -1477,11 +1489,10 @@ Integer nvim_buf_set_extmark(Buffer buffer, Integer ns_id,
   bool ephemeral = false;
 
   uint64_t id = 0;
-  int line2 = -1, hl_id = 0;
-  DecorPriority priority = DECOR_PRIORITY_BASE;
+  int line2 = -1;
+  Decoration decor = DECORATION_INIT;
   colnr_T col2 = -1;
-  VirtText virt_text = KV_INITIAL_VALUE;
-  VirtTextPos virt_text_pos = kVTEndOfLine;
+
   bool right_gravity = true;
   bool end_right_gravity = false;
   bool end_gravity_set = false;
@@ -1528,12 +1539,12 @@ Integer nvim_buf_set_extmark(Buffer buffer, Integer ns_id,
       switch (v->type) {
         case kObjectTypeString:
           hl_group = v->data.string;
-          hl_id = syn_check_group(
+          decor.hl_id = syn_check_group(
               (char_u *)(hl_group.data),
               (int)hl_group.size);
           break;
         case kObjectTypeInteger:
-          hl_id = (int)v->data.integer;
+          decor.hl_id = (int)v->data.integer;
           break;
         default:
           api_set_error(err, kErrorTypeValidation,
@@ -1546,7 +1557,7 @@ Integer nvim_buf_set_extmark(Buffer buffer, Integer ns_id,
                       "virt_text is not an Array");
         goto error;
       }
-      virt_text = parse_virt_text(v->data.array, err);
+      decor.virt_text = parse_virt_text(v->data.array, err);
       if (ERROR_SET(err)) {
         goto error;
       }
@@ -1558,9 +1569,33 @@ Integer nvim_buf_set_extmark(Buffer buffer, Integer ns_id,
       }
       String str = v->data.string;
       if (strequal("eol", str.data)) {
-        virt_text_pos = kVTEndOfLine;
+        decor.virt_text_pos = kVTEndOfLine;
       } else if (strequal("overlay", str.data)) {
-        virt_text_pos = kVTOverlay;
+        decor.virt_text_pos = kVTOverlay;
+      } else {
+        api_set_error(err, kErrorTypeValidation,
+                      "virt_text_pos: invalid value");
+        goto error;
+      }
+    } else if (strequal("virt_text_hide", k.data)) {
+      decor.virt_text_hide = api_object_to_bool(*v,
+                                                "virt_text_hide", false, err);
+      if (ERROR_SET(err)) {
+        goto error;
+      }
+    } else if (strequal("hl_mode", k.data)) {
+      if (v->type != kObjectTypeString) {
+        api_set_error(err, kErrorTypeValidation,
+                      "hl_mode is not a String");
+        goto error;
+      }
+      String str = v->data.string;
+      if (strequal("replace", str.data)) {
+        decor.hl_mode = kHlModeReplace;
+      } else if (strequal("combine", str.data)) {
+        decor.hl_mode = kHlModeCombine;
+      } else if (strequal("blend", str.data)) {
+        decor.hl_mode = kHlModeBlend;
       } else {
         api_set_error(err, kErrorTypeValidation,
                       "virt_text_pos: invalid value");
@@ -1583,7 +1618,7 @@ Integer nvim_buf_set_extmark(Buffer buffer, Integer ns_id,
                       "priority is not a valid value");
         goto error;
       }
-      priority = (DecorPriority)v->data.integer;
+      decor.priority = (DecorPriority)v->data.integer;
     } else if (strequal("right_gravity", k.data)) {
       if (v->type != kObjectTypeBoolean) {
         api_set_error(err, kErrorTypeValidation,
@@ -1631,23 +1666,23 @@ Integer nvim_buf_set_extmark(Buffer buffer, Integer ns_id,
     col2 = 0;
   }
 
-  Decoration *decor = NULL, tmp = { 0 };
+  Decoration *d = NULL;
 
-  if (kv_size(virt_text) || priority != DECOR_PRIORITY_BASE) {
+  if (ephemeral) {
+    d = &decor;
+  } else if (kv_size(decor.virt_text)
+             || decor.priority != DECOR_PRIORITY_BASE) {
     // TODO(bfredl): this is a bit sketchy. eventually we should
     // have predefined decorations for both marks/ephemerals
-    decor = ephemeral ? &tmp : xcalloc(1, sizeof(*decor));
-    decor->hl_id = hl_id;
-    decor->virt_text = virt_text;
-    decor->priority = priority;
-    decor->virt_text_pos = virt_text_pos;
-  } else if (hl_id) {
-    decor = decor_hl(hl_id);
+    d = xcalloc(1, sizeof(*d));
+    *d = decor;
+  } else if (decor.hl_id) {
+    d = decor_hl(decor.hl_id);
   }
 
   // TODO(bfredl): synergize these two branches even more
   if (ephemeral && decor_state.buf == buf) {
-    decor_add_ephemeral((int)line, (int)col, line2, col2, decor, 0);
+    decor_add_ephemeral((int)line, (int)col, line2, col2, &decor, 0);
   } else {
     if (ephemeral) {
       api_set_error(err, kErrorTypeException, "not yet implemented");
@@ -1655,14 +1690,14 @@ Integer nvim_buf_set_extmark(Buffer buffer, Integer ns_id,
     }
 
     id = extmark_set(buf, (uint64_t)ns_id, id, (int)line, (colnr_T)col,
-                     line2, col2, decor, right_gravity,
+                     line2, col2, d, right_gravity,
                      end_right_gravity, kExtmarkNoUndo);
   }
 
   return (Integer)id;
 
 error:
-  clear_virttext(&virt_text);
+  clear_virttext(&decor.virt_text);
   return 0;
 }
 
diff --git a/src/nvim/decoration.c b/src/nvim/decoration.c
index a1289f202a..9a20b06660 100644
--- a/src/nvim/decoration.c
+++ b/src/nvim/decoration.c
@@ -230,7 +230,7 @@ static void decor_add(DecorState *state, int start_row, int start_col,
   HlRange range = { start_row, start_col, end_row, end_col,
                     attr_id, MAX(priority, decor->priority),
                     kv_size(decor->virt_text) ? &decor->virt_text : NULL,
-                    decor->virt_text_pos,
+                    decor->virt_text_pos, decor->virt_text_hide, decor->hl_mode,
                     kv_size(decor->virt_text) && owned, -1 };
 
   kv_pushp(state->active);
@@ -245,7 +245,8 @@ static void decor_add(DecorState *state, int start_row, int start_col,
   kv_A(state->active, index) = range;
 }
 
-int decor_redraw_col(buf_T *buf, int col, int virt_col, DecorState *state)
+int decor_redraw_col(buf_T *buf, int col, int virt_col, bool hidden,
+                     DecorState *state)
 {
   if (col <= state->col_until) {
     return state->current;
@@ -324,7 +325,7 @@ next_mark:
     }
     if ((item.start_row == state->row && item.start_col <= col)
         && item.virt_text && item.virt_col == -1) {
-      item.virt_col = virt_col;
+      item.virt_col = (item.virt_text_hide && hidden) ? -2 : virt_col;
     }
     if (keep) {
       kv_A(state->active, j++) = item;
@@ -345,7 +346,7 @@ void decor_redraw_end(DecorState *state)
 
 VirtText *decor_redraw_virt_text(buf_T *buf, DecorState *state)
 {
-  decor_redraw_col(buf, MAXCOL, MAXCOL, state);
+  decor_redraw_col(buf, MAXCOL, MAXCOL, false, state);
   for (size_t i = 0; i < kv_size(state->active); i++) {
     HlRange item = kv_A(state->active, i);
     if (item.start_row == state->row && item.virt_text
diff --git a/src/nvim/decoration.h b/src/nvim/decoration.h
index 47bd9abbc3..264e8a4a82 100644
--- a/src/nvim/decoration.h
+++ b/src/nvim/decoration.h
@@ -23,15 +23,26 @@ typedef enum {
   kVTOverlay,
 } VirtTextPos;
 
+typedef enum {
+  kHlModeUnknown,
+  kHlModeReplace,
+  kHlModeCombine,
+  kHlModeBlend,
+} HlMode;
+
 struct Decoration
 {
   int hl_id;  // highlight group
   VirtText virt_text;
   VirtTextPos virt_text_pos;
+  bool virt_text_hide;
+  HlMode hl_mode;
   // TODO(bfredl): style, signs, etc
   DecorPriority priority;
   bool shared;  // shared decoration, don't free
 };
+#define DECORATION_INIT { 0, KV_INITIAL_VALUE, kVTEndOfLine, false, \
+                          kHlModeUnknown, DECOR_PRIORITY_BASE, false }
 
 typedef struct {
   int start_row;
@@ -39,9 +50,13 @@ typedef struct {
   int end_row;
   int end_col;
   int attr_id;
+  // TODO(bfredl): embed decoration instead, perhaps using an arena
+  // for ephemerals?
   DecorPriority priority;
   VirtText *virt_text;
   VirtTextPos virt_text_pos;
+  bool virt_text_hide;
+  HlMode hl_mode;
   bool virt_text_owned;
   int virt_col;
 } HlRange;
diff --git a/src/nvim/screen.c b/src/nvim/screen.c
index 47f1cb6423..aa3a7ae7ed 100644
--- a/src/nvim/screen.c
+++ b/src/nvim/screen.c
@@ -2096,6 +2096,8 @@ static int win_line(win_T *wp, linenr_T lnum, int startrow, int endrow,
 
   char_u buf_fold[FOLD_TEXT_LEN + 1];   // Hold value returned by get_foldtext
 
+  bool area_active = false;
+
   /* draw_state: items that are drawn in sequence: */
 #define WL_START        0               /* nothing done yet */
 # define WL_CMDLINE     WL_START + 1    /* cmdline window column */
@@ -2850,6 +2852,12 @@ static int win_line(win_T *wp, linenr_T lnum, int startrow, int endrow,
       if (draw_state == WL_LINE - 1 && n_extra == 0) {
         sign_idx = 0;
         draw_state = WL_LINE;
+
+        if (has_decor && row == startrow + filler_lines) {
+          // hide virt_text on text hidden by 'nowrap'
+          decor_redraw_col(wp->w_buffer, vcol, off, true, &decor_state);
+        }
+
         if (saved_n_extra) {
           /* Continue item from end of wrapped line. */
           n_extra = saved_n_extra;
@@ -2934,10 +2942,14 @@ static int win_line(win_T *wp, linenr_T lnum, int startrow, int endrow,
               && vcol_prev < vcol               // not at margin
               && vcol < tocol)) {
         area_attr = attr;                       // start highlighting
+        if (area_highlighting) {
+          area_active = true;
+        }
       } else if (area_attr != 0 && (vcol == tocol
                                     || (noinvcur
                                         && (colnr_T)vcol == wp->w_virtcol))) {
         area_attr = 0;                          // stop highlighting
+        area_active = false;
      }
 
       if (!n_extra) {
@@ -3397,9 +3409,15 @@ static int win_line(win_T *wp, linenr_T lnum, int startrow, int endrow,
             char_attr = hl_combine_attr(spell_attr, char_attr);
         }
 
+        if (wp->w_buffer->terminal) {
+          char_attr = hl_combine_attr(term_attrs[vcol], char_attr);
+        }
+
         if (has_decor && v > 0) {
+          bool selected = (area_active || (area_highlighting && noinvcur
+                                           && (colnr_T)vcol == wp->w_virtcol));
           int extmark_attr = decor_redraw_col(wp->w_buffer, (colnr_T)v-1, off,
-                                              &decor_state);
+                                              selected, &decor_state);
           if (extmark_attr != 0) {
             if (!attr_pri) {
               char_attr = hl_combine_attr(char_attr, extmark_attr);
@@ -3409,10 +3427,6 @@ static int win_line(win_T *wp, linenr_T lnum, int startrow, int endrow,
           }
         }
 
-        if (wp->w_buffer->terminal) {
-          char_attr = hl_combine_attr(term_attrs[vcol], char_attr);
-        }
-
         // Found last space before word: check for line break.
         if (wp->w_p_lbr && c0 == c && vim_isbreak(c)
             && !vim_isbreak((int)(*ptr))) {
@@ -4355,10 +4369,22 @@ void draw_virt_text(buf_T *buf, int *end_col, int max_col)
             virt_pos++;
             continue;
           }
-          int cells = line_putchar(&s, &linebuf_char[col], 2, false);
-          linebuf_attr[col++] = virt_attr;
+          int attr;
+          bool through = false;
+          if (item->hl_mode == kHlModeCombine) {
+            attr = hl_combine_attr(linebuf_attr[col], virt_attr);
+          } else if (item->hl_mode == kHlModeBlend) {
+            through = (*s.p == ' ');
+            attr = hl_blend_attrs(linebuf_attr[col], virt_attr, &through);
+          } else {
+            attr = virt_attr;
+          }
+          schar_T dummy[2];
+          int cells = line_putchar(&s, through ? dummy : &linebuf_char[col],
+                                   max_col-col, false);
+          linebuf_attr[col++] = attr;
           if (cells > 1) {
-            linebuf_attr[col++] = virt_attr;
+            linebuf_attr[col++] = attr;
           }
         }
         *end_col = MAX(*end_col, col);
diff --git a/test/functional/ui/decorations_spec.lua b/test/functional/ui/decorations_spec.lua
index 7a87521a6b..6cf549909a 100644
--- a/test/functional/ui/decorations_spec.lua
+++ b/test/functional/ui/decorations_spec.lua
@@ -8,6 +8,7 @@ local exec_lua = helpers.exec_lua
 local exec = helpers.exec
 local expect_events = helpers.expect_events
 local meths = helpers.meths
+local command = helpers.command
 
 describe('decorations providers', function()
   local screen
@@ -314,11 +315,30 @@ describe('extmark decorations', function()
       [2] = {foreground = Screen.colors.Brown};
       [3] = {bold = true, foreground = Screen.colors.SeaGreen};
       [4] = {background = Screen.colors.Red1, foreground = Screen.colors.Gray100};
+      [5] = {foreground = Screen.colors.Brown, bold = true};
+      [6] = {foreground = Screen.colors.DarkCyan};
+      [7] = {foreground = Screen.colors.Grey0, background = tonumber('0xff4c4c')};
+      [8] = {foreground = tonumber('0x180606'), background = tonumber('0xff4c4c')};
+      [9] = {foreground = tonumber('0xe40c0c'), background = tonumber('0xff4c4c'), bold = true};
+      [10] = {foreground = tonumber('0xb20000'), background = tonumber('0xff4c4c')};
+      [11] = {blend = 30, background = Screen.colors.Red1};
+      [12] = {foreground = Screen.colors.Brown, blend = 30, background = Screen.colors.Red1, bold = true};
+      [13] = {foreground = Screen.colors.Fuchsia};
+      [14] = {background = Screen.colors.Red1, foreground = Screen.colors.Black};
+      [15] = {background = Screen.colors.Red1, foreground = tonumber('0xb20000')};
+      [16] = {blend = 30, background = Screen.colors.Red1, foreground = Screen.colors.Magenta1};
+      [17] = {bold = true, foreground = Screen.colors.Brown, background = Screen.colors.LightGrey};
+      [18] = {background = Screen.colors.LightGrey};
+      [19] = {foreground = Screen.colors.Cyan4, background = Screen.colors.LightGrey};
+      [20] = {foreground = tonumber('0x180606'), background = tonumber('0xf13f3f')};
+      [21] = {foreground = Screen.colors.Gray0, background = tonumber('0xf13f3f')};
+      [22] = {foreground = tonumber('0xb20000'), background = tonumber('0xf13f3f')};
+      [23] = {foreground = Screen.colors.Magenta1, background = Screen.colors.LightGrey};
+      [24] = {bold = true};
     }
   end)
 
-  it('can have virtual text of overlay style', function()
-    insert [[
+  local example_text = [[
 for _,item in ipairs(items) do
     local text, hl_id_cell, count = unpack(item)
     if hl_id_cell ~= nil then
@@ -331,69 +351,164 @@ for _,item in ipairs(items) do
         colpos = colpos+1
     end
 end]]
-  feed 'gg'
 
-  local ns = meths.create_namespace 'test'
-  for i = 1,9 do
-    meths.buf_set_extmark(0, ns, i, 0, { virt_text={{'|', 'LineNr'}}, virt_text_pos='overlay'})
-    if i == 3 or (i >= 6 and i <= 9) then
-      meths.buf_set_extmark(0, ns, i, 4, { virt_text={{'|', 'NonText'}}, virt_text_pos='overlay'})
+  it('can have virtual text of overlay position', function()
+    insert(example_text)
+    feed 'gg'
+
+    local ns = meths.create_namespace 'test'
+    for i = 1,9 do
+      meths.buf_set_extmark(0, ns, i, 0, { virt_text={{'|', 'LineNr'}}, virt_text_pos='overlay'})
+      if i == 3 or (i >= 6 and i <= 9) then
+        meths.buf_set_extmark(0, ns, i, 4, { virt_text={{'|', 'NonText'}}, virt_text_pos='overlay'})
+      end
     end
-  end
-  meths.buf_set_extmark(0, ns, 9, 10, { virt_text={{'foo'}, {'bar', 'MoreMsg'}, {'!!', 'ErrorMsg'}}, virt_text_pos='overlay'})
-
-  -- can "float" beyond end of line
-  meths.buf_set_extmark(0, ns, 5, 28, { virt_text={{'loopy', 'ErrorMsg'}}, virt_text_pos='overlay'})
-  -- bound check: right edge of window
-  meths.buf_set_extmark(0, ns, 2, 26, { virt_text={{'bork bork bork ' }, {'bork bork bork', 'ErrorMsg'}}, virt_text_pos='overlay'})
-
-  screen:expect{grid=[[
-    ^for _,item in ipairs(items) do                    |
-    {2:|}   local text, hl_id_cell, count = unpack(item)  |
-    {2:|}   if hl_id_cell ~= nil tbork bork bork {4:bork bork}|
-    {2:|}   {1:|}   hl_id = hl_id_cell                        |
-    {2:|}   end                                           |
-    {2:|}   for _ = 1, (count or 1) {4:loopy}                 |
-    {2:|}   {1:|}   local cell = line[colpos]                 |
-    {2:|}   {1:|}   cell.text = text                          |
-    {2:|}   {1:|}   cell.hl_id = hl_id                        |
-    {2:|}   {1:|}   cofoo{3:bar}{4:!!}olpos+1                         |
-        end                                           |
-    end                                               |
-    {1:~                                                 }|
-    {1:~                                                 }|
-                                                      |
-  ]]}
-
-
-  -- handles broken lines
-  screen:try_resize(22, 25)
-  screen:expect{grid=[[
-    ^for _,item in ipairs(i|
-    tems) do              |
-    {2:|}   local text, hl_id_|
-    cell, count = unpack(i|
-    tem)                  |
-    {2:|}   if hl_id_cell ~= n|
-    il tbork bork bork {4:bor}|
-    {2:|}   {1:|}   hl_id = hl_id_|
-    cell                  |
-    {2:|}   end               |
-    {2:|}   for _ = 1, (count |
-    or 1) {4:loopy}           |
-    {2:|}   {1:|}   local cell = l|
-    ine[colpos]           |
-    {2:|}   {1:|}   cell.text = te|
-    xt                    |
-    {2:|}   {1:|}   cell.hl_id = h|
-    l_id                  |
-    {2:|}   {1:|}   cofoo{3:bar}{4:!!}olpo|
-    s+1                   |
-        end               |
-    end                   |
-    {1:~                     }|
-    {1:~                     }|
-                          |
-  ]]}
+    meths.buf_set_extmark(0, ns, 9, 10, { virt_text={{'foo'}, {'bar', 'MoreMsg'}, {'!!', 'ErrorMsg'}}, virt_text_pos='overlay'})
+
+    -- can "float" beyond end of line
+    meths.buf_set_extmark(0, ns, 5, 28, { virt_text={{'loopy', 'ErrorMsg'}}, virt_text_pos='overlay'})
+    -- bound check: right edge of window
+    meths.buf_set_extmark(0, ns, 2, 26, { virt_text={{'bork bork bork ' }, {'bork bork bork', 'ErrorMsg'}}, virt_text_pos='overlay'})
+
+    screen:expect{grid=[[
+      ^for _,item in ipairs(items) do                    |
+      {2:|}   local text, hl_id_cell, count = unpack(item)  |
+      {2:|}   if hl_id_cell ~= nil tbork bork bork {4:bork bork}|
+      {2:|}   {1:|}   hl_id = hl_id_cell                        |
+      {2:|}   end                                           |
+      {2:|}   for _ = 1, (count or 1) {4:loopy}                 |
+      {2:|}   {1:|}   local cell = line[colpos]                 |
+      {2:|}   {1:|}   cell.text = text                          |
+      {2:|}   {1:|}   cell.hl_id = hl_id                        |
+      {2:|}   {1:|}   cofoo{3:bar}{4:!!}olpos+1                         |
+          end                                           |
+      end                                               |
+      {1:~                                                 }|
+      {1:~                                                 }|
+                                                        |
+    ]]}
+
+
+    -- handles broken lines
+    screen:try_resize(22, 25)
+    screen:expect{grid=[[
+      ^for _,item in ipairs(i|
+      tems) do              |
+      {2:|}   local text, hl_id_|
+      cell, count = unpack(i|
+      tem)                  |
+      {2:|}   if hl_id_cell ~= n|
+      il tbork bork bork {4:bor}|
+      {2:|}   {1:|}   hl_id = hl_id_|
+      cell                  |
+      {2:|}   end               |
+      {2:|}   for _ = 1, (count |
+      or 1) {4:loopy}           |
+      {2:|}   {1:|}   local cell = l|
+      ine[colpos]           |
+      {2:|}   {1:|}   cell.text = te|
+      xt                    |
+      {2:|}   {1:|}   cell.hl_id = h|
+      l_id                  |
+      {2:|}   {1:|}   cofoo{3:bar}{4:!!}olpo|
+      s+1                   |
+          end               |
+      end                   |
+      {1:~                     }|
+      {1:~                     }|
+                            |
+    ]]}
+  end)
+
+  it('can have virtual text of overlay position and styling', function()
+    insert(example_text)
+    feed 'gg'
+    local ns = meths.create_namespace 'test'
+
+    command 'set ft=lua'
+    command 'syntax on'
+
+    screen:expect{grid=[[
+      {5:^for} _,item {5:in} {6:ipairs}(items) {5:do}                    |
+          {5:local} text, hl_id_cell, count = unpack(item)  |
+          {5:if} hl_id_cell ~= {13:nil} {5:then}                     |
+              hl_id = hl_id_cell                        |
+          {5:end}                                           |
+          {5:for} _ = {13:1}, (count {5:or} {13:1}) {5:do}                    |
+              {5:local} cell = line[colpos]                 |
+              cell.text = text                          |
+              cell.hl_id = hl_id                        |
+              colpos = colpos+{13:1}                         |
+          {5:end}                                           |
+      {5:end}                                               |
+      {1:~                                                 }|
+      {1:~                                                 }|
+                                                        |
+    ]]}
+
+    command 'hi Blendy guibg=Red blend=30'
+    meths.buf_set_extmark(0, ns, 1, 5, { virt_text={{'blendy text - here', 'Blendy'}}, virt_text_pos='overlay', hl_mode='blend'})
+    meths.buf_set_extmark(0, ns, 2, 5, { virt_text={{'combining color', 'Blendy'}}, virt_text_pos='overlay', hl_mode='combine'})
+    meths.buf_set_extmark(0, ns, 3, 5, { virt_text={{'replacing color', 'Blendy'}}, virt_text_pos='overlay', hl_mode='replace'})
+
+    meths.buf_set_extmark(0, ns, 4, 5, { virt_text={{'blendy text - here', 'Blendy'}}, virt_text_pos='overlay', hl_mode='blend', virt_text_hide=true})
+    meths.buf_set_extmark(0, ns, 5, 5, { virt_text={{'combining color', 'Blendy'}}, virt_text_pos='overlay', hl_mode='combine', virt_text_hide=true})
+    meths.buf_set_extmark(0, ns, 6, 5, { virt_text={{'replacing color', 'Blendy'}}, virt_text_pos='overlay', hl_mode='replace', virt_text_hide=true})
+
+    screen:expect{grid=[[
+      {5:^for} _,item {5:in} {6:ipairs}(items) {5:do}                    |
+          {5:l}{8:blen}{7:dy}{10:e}{7:text}{10:h}{7:-}{10:_}{7:here}ell, count = unpack(item)  |
+          {5:i}{12:c}{11:ombining color} {13:nil} {5:then}                     |
+           {11:replacing color}d_cell                        |
+          {5:e}{8:bl}{14:endy}{15:i}{14:text}{15:o}{14:-}{15:o}{14:h}{7:ere}                           |
+          {5:f}{12:co}{11:mbini}{16:n}{11:g color}t {5:or} {13:1}) {5:do}                    |
+           {11:replacing color} line[colpos]                 |
+              cell.text = text                          |
+              cell.hl_id = hl_id                        |
+              colpos = colpos+{13:1}                         |
+          {5:end}                                           |
+      {5:end}                                               |
+      {1:~                                                 }|
+      {1:~                                                 }|
+                                                        |
+    ]]}
+
+    feed 'V5G'
+    screen:expect{grid=[[
+      {17:for}{18: _,item }{17:in}{18: }{19:ipairs}{18:(items) }{17:do}                    |
+      {18:    }{17:l}{20:blen}{21:dy}{22:e}{21:text}{22:h}{21:-}{22:_}{21:here}{18:ell, count = unpack(item)}  |
+      {18:    }{17:i}{12:c}{11:ombining color}{18: }{23:nil}{18: }{17:then}                     |
+      {18:     }{11:replacing color}{18:d_cell}                        |
+      {18:    }{5:^e}{17:nd}                                           |
+          {5:f}{12:co}{11:mbini}{16:n}{11:g color}t {5:or} {13:1}) {5:do}                    |
+           {11:replacing color} line[colpos]                 |
+              cell.text = text                          |
+              cell.hl_id = hl_id                        |
+              colpos = colpos+{13:1}                         |
+          {5:end}                                           |
+      {5:end}                                               |
+      {1:~                                                 }|
+      {1:~                                                 }|
+      {24:-- VISUAL LINE --}                                 |
+    ]]}
+
+    feed 'jj'
+    screen:expect{grid=[[
+      {17:for}{18: _,item }{17:in}{18: }{19:ipairs}{18:(items) }{17:do}                    |
+      {18:    }{17:l}{20:blen}{21:dy}{22:e}{21:text}{22:h}{21:-}{22:_}{21:here}{18:ell, count = unpack(item)}  |
+      {18:    }{17:i}{12:c}{11:ombining color}{18: }{23:nil}{18: }{17:then}                     |
+      {18:     }{11:replacing color}{18:d_cell}                        |
+      {18:    }{17:end}                                           |
+      {18:    }{17:for}{18: _ = }{23:1}{18:, (count }{17:or}{18: }{23:1}{18:) }{17:do}                    |
+      {18:    }^ {18:   }{17:local}{18: cell = line[colpos]}                 |
+              cell.text = text                          |
+              cell.hl_id = hl_id                        |
+              colpos = colpos+{13:1}                         |
+          {5:end}                                           |
+      {5:end}                                               |
+      {1:~                                                 }|
+      {1:~                                                 }|
+      {24:-- VISUAL LINE --}                                 |
+    ]]}
   end)
 end)