decorations: right_align and win_col

src/nvim/api/buffer.c

@@ -1426,6 +1426,10 @@ 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.
+///                 - "right_align": display right aligned in the window.
+///               - virt_text_win_col : position the virtual text at a fixed
+///                                     window column (starting from the first
+///                                     text column)
 ///               - virt_text_hide : hide the virtual text when the background
 ///                                  text is selected or hidden due to
 ///                                  horizontal scroll 'nowrap'
@@ -1574,11 +1578,22 @@ Integer nvim_buf_set_extmark(Buffer buffer, Integer ns_id,
         decor.virt_text_pos = kVTEndOfLine;
       } else if (strequal("overlay", str.data)) {
         decor.virt_text_pos = kVTOverlay;
+      } else if (strequal("right_align", str.data)) {
+        decor.virt_text_pos = kVTRightAlign;
       } else {
         api_set_error(err, kErrorTypeValidation,
                       "virt_text_pos: invalid value");
         goto error;
       }
+    } else if (strequal("virt_text_win_col",  k.data)) {
+      if (v->type != kObjectTypeInteger) {
+        api_set_error(err, kErrorTypeValidation,
+                      "virt_text_win_col is not a Number of the correct size");
+        goto error;
+      }
+
+      decor.col = (int)v->data.integer;
+      decor.virt_text_pos = kVTWinCol;
     } else if (strequal("virt_text_hide", k.data)) {
       decor.virt_text_hide = api_object_to_bool(*v,
                                                 "virt_text_hide", false, err);
@@ -1673,6 +1688,14 @@ Integer nvim_buf_set_extmark(Buffer buffer, Integer ns_id,
     col2 = 0;
   }
 
+  if (decor.virt_text_pos == kVTRightAlign) {
+    decor.col = 0;
+    for (size_t i = 0; i < kv_size(decor.virt_text); i++) {
+      decor.col += mb_string2cells((char_u *)kv_A(decor.virt_text, i).text);
+    }
+  }
+
+
   Decoration *d = NULL;
 
   if (ephemeral) {

src/nvim/decoration.c

@@ -230,6 +230,10 @@ static void decor_add(DecorState *state, int start_row, int start_col,
                        *decor, attr_id,
                     kv_size(decor->virt_text) && owned, -1 };
 
+  if (decor->virt_text_pos == kVTEndOfLine) {
+    range.win_col = -2;  // handled separately
+  }
+
   kv_pushp(state->active);
   size_t index;
   for (index = kv_size(state->active)-1; index > 0; index--) {
@@ -242,7 +246,7 @@ 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, bool hidden,
+int decor_redraw_col(buf_T *buf, int col, int win_col, bool hidden,
                      DecorState *state)
 {
   if (col <= state->col_until) {
@@ -321,8 +325,9 @@ next_mark:
       attr = hl_combine_attr(attr, item.attr_id);
     }
     if ((item.start_row == state->row && item.start_col <= col)
-        && kv_size(item.decor.virt_text) && item.virt_col == -1) {
+        && kv_size(item.decor.virt_text)
-      item.virt_col = (item.decor.virt_text_hide && hidden) ? -2 : virt_col;
+        && item.decor.virt_text_pos == kVTOverlay && item.win_col == -1) {
+      item.win_col = (item.decor.virt_text_hide && hidden) ? -2 : win_col;
     }
     if (keep) {
       kv_A(state->active, j++) = item;
@@ -340,17 +345,22 @@ void decor_redraw_end(DecorState *state)
   state->buf = NULL;
 }
 
-VirtText decor_redraw_eol(buf_T *buf, DecorState *state, int *eol_attr)
+VirtText decor_redraw_eol(buf_T *buf, DecorState *state, int *eol_attr,
+                          bool *aligned)
 {
   decor_redraw_col(buf, MAXCOL, MAXCOL, false, state);
   VirtText text = VIRTTEXT_EMPTY;
   for (size_t i = 0; i < kv_size(state->active); i++) {
     DecorRange item = kv_A(state->active, i);
-    if (!kv_size(text)
+    if (item.start_row == state->row && kv_size(item.decor.virt_text)) {
-        && item.start_row == state->row && kv_size(item.decor.virt_text)
+      if (!kv_size(text) && item.decor.virt_text_pos == kVTEndOfLine) {
-        && item.decor.virt_text_pos == kVTEndOfLine) {
         text = item.decor.virt_text;
+      } else if (item.decor.virt_text_pos == kVTRightAlign
+                 || item.decor.virt_text_pos == kVTWinCol) {
+        *aligned = true;
       }
+    }
+
 
     if (item.decor.hl_eol && item.start_row <= state->row) {
       *eol_attr = hl_combine_attr(*eol_attr, item.attr_id);

src/nvim/decoration.h

@@ -21,6 +21,8 @@ typedef uint16_t DecorPriority;
 typedef enum {
   kVTEndOfLine,
   kVTOverlay,
+  kVTWinCol,
+  kVTRightAlign,
 } VirtTextPos;
 
 typedef enum {
@@ -41,9 +43,10 @@ struct Decoration
   // TODO(bfredl): style, signs, etc
   DecorPriority priority;
   bool shared;  // shared decoration, don't free
+  int col;  // fixed col value, like win_col
 };
 #define DECORATION_INIT { 0, KV_INITIAL_VALUE, kVTEndOfLine, false, \
-                          kHlModeUnknown, false, DECOR_PRIORITY_BASE, false }
+                          kHlModeUnknown, false, DECOR_PRIORITY_BASE, false, 0 }
 
 typedef struct {
   int start_row;
@@ -53,7 +56,7 @@ typedef struct {
   Decoration decor;
   int attr_id;  // cached lookup of decor.hl_id
   bool virt_text_owned;
-  int virt_col;
+  int win_col;
 } DecorRange;
 
 typedef struct {

src/nvim/screen.c

@@ -2101,6 +2101,7 @@ static int win_line(win_T *wp, linenr_T lnum, int startrow, int endrow,
   bool search_attr_from_match = false;  // if search_attr is from :match
   bool has_decor = false;               // this buffer has decoration
   bool do_virttext = false;             // draw virtual text for this line
+  int win_col_offset;                   // offsett for window columns
 
   char_u buf_fold[FOLD_TEXT_LEN + 1];   // Hold value returned by get_foldtext
 
@@ -2790,6 +2791,10 @@ static int win_line(win_T *wp, linenr_T lnum, int startrow, int endrow,
         }
       }
 
+      if (draw_state == WL_NR && n_extra == 0) {
+        win_col_offset = off;
+      }
+
       if (wp->w_briopt_sbr && draw_state == WL_BRI - 1
           && n_extra == 0 && *p_sbr != NUL) {
         // draw indent after showbreak value
@@ -2904,7 +2909,7 @@ static int win_line(win_T *wp, linenr_T lnum, int startrow, int endrow,
           && vcol >= (long)wp->w_virtcol)
          || (number_only && draw_state > WL_NR))
         && filler_todo <= 0) {
-      draw_virt_text(buf, &col, grid->Columns);
+      draw_virt_text(buf, win_col_offset, &col, grid->Columns);
       grid_put_linebuf(grid, row, 0, col, -grid->Columns, wp->w_p_rl, wp,
                        wp->w_hl_attr_normal, false);
       // Pretend we have finished updating the window.  Except when
@@ -3945,13 +3950,15 @@ static int win_line(win_T *wp, linenr_T lnum, int startrow, int endrow,
         draw_color_col = advance_color_col(VCOL_HLC, &color_cols);
 
       VirtText virt_text = KV_INITIAL_VALUE;
+      bool has_aligned = false;
       if (err_text) {
         int hl_err = syn_check_group((char_u *)S_LEN("ErrorMsg"));
         kv_push(virt_text, ((VirtTextChunk){ .text = err_text,
                                              .hl_id = hl_err }));
         do_virttext = true;
       } else if (has_decor) {
-        virt_text = decor_redraw_eol(wp->w_buffer, &decor_state, &line_attr);
+        virt_text = decor_redraw_eol(wp->w_buffer, &decor_state, &line_attr,
+                                     &has_aligned);
         if (kv_size(virt_text)) {
           do_virttext = true;
         }
@@ -3963,7 +3970,8 @@ static int win_line(win_T *wp, linenr_T lnum, int startrow, int endrow,
             grid->Columns * (row - startrow + 1) + v
             && lnum != wp->w_cursor.lnum)
            || draw_color_col || line_attr_lowprio || line_attr
-           || diff_hlf != (hlf_T)0 || do_virttext)) {
+           || diff_hlf != (hlf_T)0 || do_virttext
+           || has_aligned)) {
         int rightmost_vcol = 0;
         int i;
 
@@ -4001,7 +4009,7 @@ static int win_line(win_T *wp, linenr_T lnum, int startrow, int endrow,
         }
 
         int base_attr = hl_combine_attr(line_attr_lowprio, diff_attr);
-        if (base_attr || line_attr) {
+        if (base_attr || line_attr || has_aligned) {
           rightmost_vcol = INT_MAX;
         }
 
@@ -4079,7 +4087,7 @@ static int win_line(win_T *wp, linenr_T lnum, int startrow, int endrow,
         }
       }
 
-      draw_virt_text(buf, &col, grid->Columns);
+      draw_virt_text(buf, win_col_offset, &col, grid->Columns);
       grid_put_linebuf(grid, row, 0, col, grid->Columns, wp->w_p_rl, wp,
                        wp->w_hl_attr_normal, false);
       row++;
@@ -4300,7 +4308,7 @@ static int win_line(win_T *wp, linenr_T lnum, int startrow, int endrow,
         && !wp->w_p_rl;              // Not right-to-left.
 
       int draw_col = col - boguscols;
-      draw_virt_text(buf, &draw_col, grid->Columns);
+      draw_virt_text(buf, win_col_offset, &draw_col, grid->Columns);
       grid_put_linebuf(grid, row, 0, draw_col, grid->Columns, wp->w_p_rl,
                        wp, wp->w_hl_attr_normal, wrap);
       if (wrap) {
@@ -4377,21 +4385,31 @@ static int win_line(win_T *wp, linenr_T lnum, int startrow, int endrow,
   return row;
 }
 
-void draw_virt_text(buf_T *buf, int *end_col, int max_col)
+void draw_virt_text(buf_T *buf, int col_off, int *end_col, int max_col)
 {
   DecorState *state = &decor_state;
+  int right_pos = max_col;
   for (size_t i = 0; i < kv_size(state->active); i++) {
     DecorRange *item = &kv_A(state->active, i);
-    if (item->start_row == state->row && kv_size(item->decor.virt_text)
+    if (item->start_row == state->row && kv_size(item->decor.virt_text)) {
-        && item->decor.virt_text_pos == kVTOverlay
+      if (item->win_col == -1) {
-        && item->virt_col >= 0) {
+        if (item->decor.virt_text_pos == kVTRightAlign) {
+          right_pos -= item->decor.col;
+          item->win_col = right_pos;
+        } else if (item->decor.virt_text_pos == kVTWinCol) {
+          item->win_col = MAX(item->decor.col+col_off, 0);
+        }
+      }
+      if (item->win_col < 0) {
+        continue;
+      }
       VirtText vt = item->decor.virt_text;
       HlMode hl_mode = item->decor.hl_mode;
       LineState s = LINE_STATE("");
       int virt_attr = 0;
-        int col = item->virt_col;
+      int col = item->win_col;
       size_t virt_pos = 0;
-        item->virt_col = -2;  // deactivate
+      item->win_col = -2;  // deactivate
 
       while (col < max_col) {
         if (!*s.p) {

test/functional/ui/decorations_spec.lua

@@ -333,6 +333,35 @@ describe('decorations providers', function()
     ]]}
   end)
 
+  it('can have virtual text of the style: right_align', function()
+    insert(mulholland)
+    setup_provider [[
+      local hl = a.nvim_get_hl_id_by_name "ErrorMsg"
+      local test_ns = a.nvim_create_namespace "mulholland"
+      function on_do(event, ...)
+        if event == "line" then
+          local win, buf, line = ...
+          a.nvim_buf_set_extmark(buf, test_ns, line, 0, {
+            virt_text = {{'+'}, {string.rep(' ', line+1), 'ErrorMsg'}};
+            virt_text_pos='right_align';
+            ephemeral = true;
+          })
+        end
+      end
+    ]]
+
+    screen:expect{grid=[[
+      // just to see if there was an acciden+{2: }|
+      // on Mulholland Drive               +{2:  }|
+      try_start();                        +{2:   }|
+      bufref_T save_buf;                 +{2:    }|
+      switch_buffer(&save_buf, buf);    +{2:     }|
+      posp = getmark(mark, false);     +{2:      }|
+      restore_buffer(&save_buf);^      +{2:       }|
+                                              |
+    ]]}
+  end)
+
   it('can highlight beyond EOL', function()
     insert(mulholland)
     setup_provider [[
@@ -366,7 +395,7 @@ describe('decorations providers', function()
 end)
 
 describe('extmark decorations', function()
-  local screen
+  local screen, ns
   before_each( function()
     clear()
     screen = Screen.new(50, 15)
@@ -397,6 +426,8 @@ describe('extmark decorations', function()
       [23] = {foreground = Screen.colors.Magenta1, background = Screen.colors.LightGrey};
       [24] = {bold = true};
     }
+
+    ns = meths.create_namespace 'test'
   end)
 
   local example_text = [[
@@ -417,7 +448,6 @@ end]]
     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
@@ -484,7 +514,6 @@ 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'
@@ -572,4 +601,88 @@ end]]
       {24:-- VISUAL LINE --}                                 |
     ]]}
   end)
+
+  it('can have virtual text of fixed win_col position', function()
+    insert(example_text)
+    feed 'gg'
+    meths.buf_set_extmark(0, ns, 1, 0, { virt_text={{'Very', 'ErrorMsg'}},   virt_text_win_col=31, hl_mode='blend'})
+    meths.buf_set_extmark(0, ns, 2, 10, { virt_text={{'Much', 'ErrorMsg'}},   virt_text_win_col=31, hl_mode='blend'})
+    meths.buf_set_extmark(0, ns, 3, 15, { virt_text={{'Error', 'ErrorMsg'}}, virt_text_win_col=31, hl_mode='blend'})
+    meths.buf_set_extmark(0, ns, 7, 21, { virt_text={{'-', 'NonText'}}, virt_text_win_col=4, hl_mode='blend'})
+
+    screen:expect{grid=[[
+      ^for _,item in ipairs(items) do                    |
+          local text, hl_id_cell, cou{4:Very} unpack(item)  |
+          if hl_id_cell ~= nil then  {4:Much}               |
+              hl_id = hl_id_cell     {4:Error}              |
+          end                                           |
+          for _ = 1, (count or 1) do                    |
+              local cell = line[colpos]                 |
+          {1:-}   cell.text = text                          |
+              cell.hl_id = hl_id                        |
+              colpos = colpos+1                         |
+          end                                           |
+      end                                               |
+      {1:~                                                 }|
+      {1:~                                                 }|
+                                                        |
+    ]]}
+
+    feed '3G12|i<cr><esc>'
+    screen:expect{grid=[[
+      for _,item in ipairs(items) do                    |
+          local text, hl_id_cell, cou{4:Very} unpack(item)  |
+          if hl_i                    {4:Much}               |
+      ^d_cell ~= nil then                                |
+              hl_id = hl_id_cell     {4:Error}              |
+          end                                           |
+          for _ = 1, (count or 1) do                    |
+              local cell = line[colpos]                 |
+          {1:-}   cell.text = text                          |
+              cell.hl_id = hl_id                        |
+              colpos = colpos+1                         |
+          end                                           |
+      end                                               |
+      {1:~                                                 }|
+                                                        |
+    ]]}
+
+    feed 'u:<cr>'
+    screen:expect{grid=[[
+      for _,item in ipairs(items) do                    |
+          local text, hl_id_cell, cou{4:Very} unpack(item)  |
+          if hl_i^d_cell ~= nil then  {4:Much}               |
+              hl_id = hl_id_cell     {4:Error}              |
+          end                                           |
+          for _ = 1, (count or 1) do                    |
+              local cell = line[colpos]                 |
+          {1:-}   cell.text = text                          |
+              cell.hl_id = hl_id                        |
+              colpos = colpos+1                         |
+          end                                           |
+      end                                               |
+      {1:~                                                 }|
+      {1:~                                                 }|
+      :                                                 |
+    ]]}
+
+    feed '8|i<cr><esc>'
+    screen:expect{grid=[[
+      for _,item in ipairs(items) do                    |
+          local text, hl_id_cell, cou{4:Very} unpack(item)  |
+          if                                            |
+      ^hl_id_cell ~= nil then         {4:Much}               |
+              hl_id = hl_id_cell     {4:Error}              |
+          end                                           |
+          for _ = 1, (count or 1) do                    |
+              local cell = line[colpos]                 |
+          {1:-}   cell.text = text                          |
+              cell.hl_id = hl_id                        |
+              colpos = colpos+1                         |
+          end                                           |
+      end                                               |
+      {1:~                                                 }|
+                                                        |
+    ]]}
+  end)
 end)