Merge pull request #24486 from zeertzjq/backport

Backport to release-0.9

runtime/doc/ui.txt

@@ -199,7 +199,7 @@ the editor.
 	The following keys are deprecated:
 
 	`hl_id`:	Use `attr_id` instead.
-	`hl_lm`:	Use `attr_id_lm` instead.
+	`id_lm`:	Use `attr_id_lm` instead.
 
 ["option_set", name, value] ~
 	UI-related option changed, where `name` is one of:
@@ -336,7 +336,7 @@ numerical highlight ids to the actual attributes.
 
 	Highlights are always transmitted both for both the RGB format and as
 	terminal 256-color codes, as the `rgb_attr` and `cterm_attr` parameters
-	respectively. The |ui-rgb| option has no effect effect anymore.
+	respectively. The |ui-rgb| option has no effect anymore.
 	Most external UIs will only need to store and use the `rgb_attr`
 	attributes.
 
@@ -352,7 +352,7 @@ numerical highlight ids to the actual attributes.
 	|ui-hlstate| extension explained below.
 
 ["hl_group_set", name, hl_id] ~
-	The bulitin highlight group `name` was set to use the attributes `hl_id`
+	The built-in highlight group `name` was set to use the attributes `hl_id`
 	defined by a previous `hl_attr_define` call. This event is not needed
 	to render the grids which use attribute ids directly, but is useful
 	for a UI who want to render its own elements with consistent
@@ -640,7 +640,8 @@ tabs.
 	the top line of a window moved since `win_viewport` was last emitted.
 	It is intended to be used to implement smooth scrolling. For this
 	purpose it only counts "virtual" or "displayed" lines, so folds
-	only count as one line.
+	only count as one line. When scrolling more than a full screen it is
+	an approximate value.
 
 	All updates, such as `grid_line`, in a batch affects the new viewport,
 	despite the fact that `win_viewport` is received after the updates.
@@ -723,7 +724,7 @@ For command-line 'wildmenu' UI events, activate |ui-popupmenu|.
 	to distinguish different command lines active at the same time. The
 	first invoked command line has level 1, the next recursively-invoked
 	prompt has level 2. A command line invoked from the |cmdline-window|
-	has a higher level than than the edited command line.
+	has a higher level than the edited command line.
 
 ["cmdline_pos", pos, level] ~
 	Change the cursor position in the cmdline.

src/nvim/buffer_defs.h

@@ -1223,6 +1223,9 @@ struct window_S {
 
   bool w_viewport_invalid;
   linenr_T w_viewport_last_topline;  // topline when the viewport was last updated
+  linenr_T w_viewport_last_botline;  // botline when the viewport was last updated
+  linenr_T w_viewport_last_topfill;  // topfill when the viewport was last updated
+  linenr_T w_viewport_last_skipcol;  // skipcol when the viewport was last updated
 
   // w_cline_height is the number of physical lines taken by the buffer line
   // that the cursor is on.  We use this to avoid extra calls to plines_win().

src/nvim/fold.c

@@ -771,7 +771,7 @@ void clearFolding(win_T *win)
 /// The changes in lines from top to bot (inclusive).
 void foldUpdate(win_T *wp, linenr_T top, linenr_T bot)
 {
-  if (disable_fold_update || State & MODE_INSERT) {
+  if (disable_fold_update || (State & MODE_INSERT && !foldmethodIsIndent(wp))) {
     return;
   }
 

src/nvim/main.c

@@ -629,6 +629,8 @@ int main(int argc, char **argv)
   }
 
   if (params.luaf != NULL) {
+    // Like "--cmd", "+", "-c" and "-S", don't truncate messages.
+    msg_scroll = true;
     bool lua_ok = nlua_exec_file(params.luaf);
     TIME_MSG("executing Lua -l script");
     getout(lua_ok ? 0 : 1);

src/nvim/mouse.c

@@ -1300,14 +1300,13 @@ retnomove:
         }
         first = false;
 
-        if (hasFolding(curwin->w_topline, NULL, &curwin->w_topline)
-            && curwin->w_topline == curbuf->b_ml.ml_line_count) {
-          break;
-        }
-
         if (curwin->w_topfill > 0) {
           curwin->w_topfill--;
         } else {
+          if (hasFolding(curwin->w_topline, NULL, &curwin->w_topline)
+              && curwin->w_topline == curbuf->b_ml.ml_line_count) {
+            break;
+          }
           curwin->w_topline++;
           curwin->w_topfill = win_get_fill(curwin, curwin->w_topline);
         }
@@ -1393,8 +1392,7 @@ bool mouse_comp_pos(win_T *win, int *rowp, int *colp, linenr_T *lnump)
 
   while (row > 0) {
     // Don't include filler lines in "count"
-    if (win_may_fill(win)
+    if (win_may_fill(win)) {
-        && !hasFoldingWin(win, lnum, NULL, NULL, true, NULL)) {
       if (lnum == win->w_topline) {
         row -= win->w_topfill;
       } else {

src/nvim/move.c

@@ -943,21 +943,20 @@ void textpos2screenpos(win_T *wp, pos_T *pos, int *rowp, int *scolp, int *ccolp,
   bool visible_row = false;
   bool is_folded = false;
 
-  if (pos->lnum >= wp->w_topline && pos->lnum <= wp->w_botline) {
+  linenr_T lnum = pos->lnum;
-    linenr_T lnum = pos->lnum;
+  if (lnum >= wp->w_topline && lnum <= wp->w_botline) {
     is_folded = hasFoldingWin(wp, lnum, &lnum, NULL, true, NULL);
     row = plines_m_win(wp, wp->w_topline, lnum - 1) + 1;
     // Add filler lines above this buffer line.
-    row += win_get_fill(wp, lnum);
+    row += lnum == wp->w_topline ? wp->w_topfill : win_get_fill(wp, lnum);
     visible_row = true;
-  } else if (!local || pos->lnum < wp->w_topline) {
+  } else if (!local || lnum < wp->w_topline) {
     row = 0;
   } else {
     row = wp->w_height_inner;
   }
 
-  bool existing_row = (pos->lnum > 0
+  bool existing_row = (lnum > 0 && lnum <= wp->w_buffer->b_ml.ml_line_count);
-                       && pos->lnum <= wp->w_buffer->b_ml.ml_line_count);
 
   if ((local || visible_row) && existing_row) {
     const colnr_T off = win_col_off(wp);
@@ -965,6 +964,7 @@ void textpos2screenpos(win_T *wp, pos_T *pos, int *rowp, int *scolp, int *ccolp,
       row += local ? 0 : wp->w_winrow + wp->w_winrow_off;
       coloff = (local ? 0 : wp->w_wincol + wp->w_wincol_off) + 1 + off;
     } else {
+      assert(lnum == pos->lnum);
       getvcol(wp, pos, &scol, &ccol, &ecol);
 
       // similar to what is done in validate_cursor_col()
@@ -972,6 +972,10 @@ void textpos2screenpos(win_T *wp, pos_T *pos, int *rowp, int *scolp, int *ccolp,
       col += off;
       int width = wp->w_width_inner - off + win_col_off2(wp);
 
+      if (lnum == wp->w_topline) {
+        col -= wp->w_skipcol;
+      }
+
       // long line wrapping, adjust row
       if (wp->w_p_wrap && col >= (colnr_T)wp->w_width_inner && width > 0) {
         // use same formula as what is used in curs_columns()

src/nvim/plines.c

@@ -38,8 +38,7 @@
 /// @param winheight when true limit to window height
 int plines_win(win_T *wp, linenr_T lnum, bool winheight)
 {
-  // Check for filler lines above this buffer line.  When folded the result
+  // Check for filler lines above this buffer line.
-  // is one line anyway.
   return plines_win_nofill(wp, lnum, winheight) + win_get_fill(wp, lnum);
 }
 
@@ -133,8 +132,7 @@ int plines_win_nofold(win_T *wp, linenr_T lnum)
 /// used from the start of the line to the given column number.
 int plines_win_col(win_T *wp, linenr_T lnum, long column)
 {
-  // Check for filler lines above this buffer line.  When folded the result
+  // Check for filler lines above this buffer line.
-  // is one line anyway.
   int lines = win_get_fill(wp, lnum);
 
   if (!wp->w_p_wrap) {
@@ -194,16 +192,12 @@ int plines_win_col(win_T *wp, linenr_T lnum, long column)
 int plines_win_full(win_T *wp, linenr_T lnum, linenr_T *const nextp, bool *const foldedp,
                     const bool cache)
 {
-  bool folded = hasFoldingWin(wp, lnum, NULL, nextp, cache, NULL);
+  bool folded = hasFoldingWin(wp, lnum, &lnum, nextp, cache, NULL);
-  if (foldedp) {
+  if (foldedp != NULL) {
     *foldedp = folded;
   }
-  if (folded) {
+  return ((folded ? 1 : plines_win_nofill(wp, lnum, true)) +
-    return 1;
+          (lnum == wp->w_topline ? wp->w_topfill : win_get_fill(wp, lnum)));
-  } else if (lnum == wp->w_topline) {
-    return plines_win_nofill(wp, lnum, true) + wp->w_topfill;
-  }
-  return plines_win(wp, lnum, true);
 }
 
 int plines_m_win(win_T *wp, linenr_T first, linenr_T last)
@@ -536,3 +530,68 @@ static int win_nolbr_chartabsize(chartabsize_T *cts, int *headp)
   }
   return n;
 }
+
+/// Get the number of screen lines a range of text will take in window "wp".
+///
+/// @param[in] start_lnum  Starting line number, 1-based inclusive.
+/// @param[in] start_vcol  >= 0: Starting virtual column index on "start_lnum",
+///                              0-based inclusive, rounded down to full screen lines.
+///                        < 0:  Count a full "start_lnum", including filler lines above.
+/// @param[in] end_lnum    Ending line number, 1-based inclusive.
+/// @param[in] end_vcol    >= 0: Ending virtual column index on "end_lnum",
+///                              0-based exclusive, rounded up to full screen lines.
+///                        < 0:  Count a full "end_lnum", not including filler lines below.
+/// @param[out] fill       If not NULL, set to the number of filler lines in the range.
+int64_t win_text_height(win_T *const wp, const linenr_T start_lnum, const int64_t start_vcol,
+                        const linenr_T end_lnum, const int64_t end_vcol, int64_t *const fill)
+{
+  int width1 = 0;
+  int width2 = 0;
+  if (start_vcol >= 0 || end_vcol >= 0) {
+    width1 = wp->w_width_inner - win_col_off(wp);
+    width2 = width1 + win_col_off2(wp);
+    width1 = MAX(width1, 0);
+    width2 = MAX(width2, 0);
+  }
+
+  int64_t height_sum_fill = 0;
+  int64_t height_cur_nofill = 0;
+  int64_t height_sum_nofill = 0;
+  linenr_T lnum = start_lnum;
+
+  if (start_vcol >= 0) {
+    linenr_T lnum_next = lnum;
+    const bool folded = hasFoldingWin(wp, lnum, &lnum, &lnum_next, true, NULL);
+    height_cur_nofill = folded ? 1 : plines_win_nofill(wp, lnum, false);
+    height_sum_nofill += height_cur_nofill;
+    const int64_t row_off = (start_vcol < width1 || width2 <= 0)
+                            ? 0
+                            : 1 + (start_vcol - width1) / width2;
+    height_sum_nofill -= MIN(row_off, height_cur_nofill);
+    lnum = lnum_next + 1;
+  }
+
+  while (lnum <= end_lnum) {
+    linenr_T lnum_next = lnum;
+    const bool folded = hasFoldingWin(wp, lnum, &lnum, &lnum_next, true, NULL);
+    height_sum_fill += win_get_fill(wp, lnum);
+    height_cur_nofill = folded ? 1 : plines_win_nofill(wp, lnum, false);
+    height_sum_nofill += height_cur_nofill;
+    lnum = lnum_next + 1;
+  }
+
+  if (end_vcol >= 0) {
+    height_sum_nofill -= height_cur_nofill;
+    const int64_t row_off = end_vcol == 0
+                            ? 0
+                            : (end_vcol <= width1 || width2 <= 0)
+                              ? 1
+                              : 1 + (end_vcol - width1 + width2 - 1) / width2;
+    height_sum_nofill += MIN(row_off, height_cur_nofill);
+  }
+
+  if (fill != NULL) {
+    *fill = height_sum_fill;
+  }
+  return height_sum_fill + height_sum_nofill;
+}

src/nvim/window.c

@@ -990,29 +990,56 @@ void ui_ext_win_viewport(win_T *wp)
   // NOTE: The win_viewport command is delayed until the next flush when there are pending updates.
   // This ensures that the updates and the viewport are sent together.
   if ((wp == curwin || ui_has(kUIMultigrid)) && wp->w_viewport_invalid && wp->w_redr_type == 0) {
-    int botline = wp->w_botline;
+    const linenr_T line_count = wp->w_buffer->b_ml.ml_line_count;
-    int line_count = wp->w_buffer->b_ml.ml_line_count;
+    // Avoid ml_get errors when producing "scroll_delta".
-    if (botline == line_count + 1 && wp->w_empty_rows == 0) {
+    const linenr_T cur_topline = MIN(wp->w_topline, line_count);
+    const linenr_T cur_botline = MIN(wp->w_botline, line_count);
+    int64_t delta = 0;
+    linenr_T last_topline = wp->w_viewport_last_topline;
+    linenr_T last_botline = wp->w_viewport_last_botline;
+    int last_topfill = wp->w_viewport_last_topfill;
+    int64_t last_skipcol = wp->w_viewport_last_skipcol;
+    if (last_topline > line_count) {
+      delta -= last_topline - line_count;
+      last_topline = line_count;
+      last_topfill = 0;
+      last_skipcol = MAXCOL;
+    }
+    last_botline = MIN(last_botline, line_count);
+    if (cur_topline < last_topline
+        || (cur_topline == last_topline && wp->w_skipcol < last_skipcol)) {
+      if (last_topline > 0 && cur_botline < last_topline) {
+        // Scrolling too many lines: only give an approximate "scroll_delta".
+        delta -= win_text_height(wp, cur_topline, wp->w_skipcol, cur_botline, 0, NULL);
+        delta -= last_topline - cur_botline;
+      } else {
+        delta -= win_text_height(wp, cur_topline, wp->w_skipcol, last_topline, last_skipcol, NULL);
+      }
+    } else if (cur_topline > last_topline
+               || (cur_topline == last_topline && wp->w_skipcol > last_skipcol)) {
+      if (last_botline > 0 && cur_topline > last_botline) {
+        // Scrolling too many lines: only give an approximate "scroll_delta".
+        delta += win_text_height(wp, last_topline, last_skipcol, last_botline, 0, NULL);
+        delta += cur_topline - last_botline;
+      } else {
+        delta += win_text_height(wp, last_topline, last_skipcol, cur_topline, wp->w_skipcol, NULL);
+      }
+    }
+    delta += last_topfill;
+    delta -= wp->w_topfill;
+    linenr_T ev_botline = wp->w_botline;
+    if (ev_botline == line_count + 1 && wp->w_empty_rows == 0) {
       // TODO(bfredl): The might be more cases to consider, like how does this
       // interact with incomplete final line? Diff filler lines?
-      botline = wp->w_buffer->b_ml.ml_line_count;
+      ev_botline = line_count;
     }
-    int scroll_delta = 0;
+    ui_call_win_viewport(wp->w_grid_alloc.handle, wp->handle, wp->w_topline - 1, ev_botline,
-    if (wp->w_viewport_last_topline > line_count) {
+                         wp->w_cursor.lnum - 1, wp->w_cursor.col, line_count, delta);
-      scroll_delta -= wp->w_viewport_last_topline - line_count;
-      wp->w_viewport_last_topline = line_count;
-    }
-    if (wp->w_topline < wp->w_viewport_last_topline) {
-      scroll_delta -= plines_m_win(wp, wp->w_topline, wp->w_viewport_last_topline - 1);
-    } else if (wp->w_topline > wp->w_viewport_last_topline
-               && wp->w_topline <= line_count) {
-      scroll_delta += plines_m_win(wp, wp->w_viewport_last_topline, wp->w_topline - 1);
-    }
-    ui_call_win_viewport(wp->w_grid_alloc.handle, wp->handle, wp->w_topline - 1,
-                         botline, wp->w_cursor.lnum - 1, wp->w_cursor.col,
-                         line_count, scroll_delta);
     wp->w_viewport_invalid = false;
     wp->w_viewport_last_topline = wp->w_topline;
+    wp->w_viewport_last_botline = wp->w_botline;
+    wp->w_viewport_last_topfill = wp->w_topfill;
+    wp->w_viewport_last_skipcol = wp->w_skipcol;
   }
 }
 

test/functional/core/remote_spec.lua

@@ -106,6 +106,7 @@ describe('Remote', function()
       eq({ '0', '' }, run_remote('--remote-expr', 'setline(1, "Yo")'))
       eq({ 'Yo', '' }, run_remote('--remote-expr', 'getline(1)'))
       expect('Yo')
+      eq({ ('k'):rep(1234), '' }, run_remote('--remote-expr', 'repeat("k", 1234)'))
       eq({ '1.25', '' }, run_remote('--remote-expr', '1.25'))
       eq({ 'no', '' }, run_remote('--remote-expr', '0z6E6F'))
       eq({ '\t', '' }, run_remote('--remote-expr', '"\t"'))

test/functional/core/startup_spec.lua

@@ -99,10 +99,11 @@ describe('startup', function()
     it('os.exit() sets Nvim exitcode', function()
       -- tricky: LeakSanitizer triggers on os.exit() and disrupts the return value, disable it
       exec_lua [[
-        local asan_options = os.getenv 'ASAN_OPTIONS'
+        local asan_options = os.getenv('ASAN_OPTIONS') or ''
-        if asan_options ~= nil and asan_options ~= '' then
+        if asan_options ~= '' then
-          vim.loop.os_setenv('ASAN_OPTIONS', asan_options..':detect_leaks=0')
+          asan_options = asan_options .. ':'
         end
+        vim.loop.os_setenv('ASAN_OPTIONS', asan_options .. ':detect_leaks=0')
       ]]
       -- nvim -l foo.lua -arg1 -- a b c
       assert_l_out([[
@@ -141,6 +142,14 @@ describe('startup', function()
       eq(0, eval('v:shell_error'))
     end)
 
+    it('does not truncate long print() message', function()
+      assert_l_out(('k'):rep(1234),
+        nil,
+        nil,
+        '-',
+        "print(('k'):rep(1234))")
+    end)
+
     it('sets _G.arg', function()
       -- nvim -l foo.lua
       assert_l_out([[
@@ -217,6 +226,15 @@ describe('startup', function()
     end)
   end)
 
+  it('--cmd/-c/+ do not truncate long Lua print() message with --headless', function()
+    local out = funcs.system({ nvim_prog, '-u', 'NONE', '-i', 'NONE', '--headless',
+                               '--cmd', 'lua print(("A"):rep(1234))',
+                               '-c', 'lua print(("B"):rep(1234))',
+                               '+lua print(("C"):rep(1234))',
+                               '+q' })
+    eq(('A'):rep(1234) .. '\r\n' .. ('B'):rep(1234) .. '\r\n' .. ('C'):rep(1234), out)
+  end)
+
   it('pipe at both ends: has("ttyin")==0 has("ttyout")==0', function()
     -- system() puts a pipe at both ends.
     local out = funcs.system({ nvim_prog, '-u', 'NONE', '-i', 'NONE', '--headless',

test/functional/editor/fold_spec.lua

@@ -7,6 +7,7 @@ local expect = helpers.expect
 local command = helpers.command
 local funcs = helpers.funcs
 local eq = helpers.eq
+local neq = helpers.neq
 
 describe('Folds', function()
   local tempfname = 'Xtest-fold.txt'
@@ -417,4 +418,31 @@ a]], '13m7')
     eq(1, funcs.foldlevel(1))
     eq(1, funcs.foldlevel(2))
   end)
+
+  it("doesn't open folds with indent method when inserting lower foldlevel line", function()
+    insert([[
+      insert an unindented line under this line
+      keep the lines under this line folded
+        keep this line folded 1
+        keep this line folded 2
+    ]])
+    command('set foldmethod=indent shiftwidth=2 noautoindent')
+    eq(1, funcs.foldlevel(1))
+    eq(1, funcs.foldlevel(2))
+    eq(2, funcs.foldlevel(3))
+    eq(2, funcs.foldlevel(4))
+
+    feed('zo') -- open the outer fold
+    neq(-1, funcs.foldclosed(3)) -- make sure the inner fold is not open
+
+    feed('gg0oa<Esc>') -- insert unindented line
+
+    eq(1, funcs.foldlevel(1)) --|  insert an unindented line under this line
+    eq(0, funcs.foldlevel(2)) --|a
+    eq(1, funcs.foldlevel(3)) --|  keep the lines under this line folded
+    eq(2, funcs.foldlevel(4)) --|    keep this line folded 1
+    eq(2, funcs.foldlevel(5)) --|    keep this line folded 2
+
+    neq(-1, funcs.foldclosed(4)) -- make sure the inner fold is still not open
+  end)
 end)

test/functional/ui/fold_spec.lua

@@ -7,7 +7,6 @@ local insert = helpers.insert
 local funcs = helpers.funcs
 local meths = helpers.meths
 local exec = helpers.exec
-local exec_lua = helpers.exec_lua
 local assert_alive = helpers.assert_alive
 
 
@@ -43,6 +42,7 @@ describe("folded lines", function()
         [10] = {background = Screen.colors.LightGrey, underline = true},
         [11] = {bold=true},
         [12] = {background = Screen.colors.Grey90},
+        [16] = {background = Screen.colors.LightGrey},
       })
     end)
 
@@ -1892,21 +1892,19 @@ describe("folded lines", function()
       end
     end)
 
-    it('fold attached virtual lines are drawn correctly #21837', function()
+    it('fold attached virtual lines are drawn and scrolled correctly #21837', function()
       funcs.setline(1, 'line 1')
       funcs.setline(2, 'line 2')
       funcs.setline(3, 'line 3')
       funcs.setline(4, 'line 4')
       feed("zfj")
-      exec_lua([[
+      local ns = meths.create_namespace('ns')
-        local ns = vim.api.nvim_create_namespace("ns")
+      meths.buf_set_extmark(0, ns, 0, 0, { virt_lines_above = true, virt_lines = {{{"virt_line above line 1", ""}}} })
-        vim.api.nvim_buf_set_extmark(0, ns, 0, 0, { virt_lines_above = true, virt_lines = {{{"virt_line above line 1", ""}}} })
+      meths.buf_set_extmark(0, ns, 1, 0, { virt_lines = {{{"virt_line below line 2", ""}}} })
-        vim.api.nvim_buf_set_extmark(0, ns, 1, 0, { virt_lines = {{{"virt_line below line 2", ""}}} })
+      meths.buf_set_extmark(0, ns, 2, 0, { virt_lines_above = true, virt_lines = {{{"virt_line above line 3", ""}}} })
-        vim.api.nvim_buf_set_extmark(0, ns, 2, 0, { virt_lines_above = true, virt_lines = {{{"virt_line above line 3", ""}}} })
+      meths.buf_set_extmark(0, ns, 3, 0, { virt_lines = {{{"virt_line below line 4", ""}}} })
-        vim.api.nvim_buf_set_extmark(0, ns, 3, 0, { virt_lines = {{{"virt_line below line 4", ""}}} })
-      ]])
       if multigrid then
-        screen:expect([[
+        screen:expect{grid=[[
         ## grid 1
           [2:---------------------------------------------]|
           [2:---------------------------------------------]|
@@ -1926,7 +1924,9 @@ describe("folded lines", function()
           {1:~                                            }|
         ## grid 3
                                                        |
-        ]])
+        ]], win_viewport={
+          [2] = {win = {id = 1000}, topline = 0, botline = 5, curline = 0, curcol = 0, linecount = 4, sum_scroll_delta = 0};
+        }}
       else
         screen:expect([[
           {5:^+--  2 lines: line 1·························}|
@@ -1942,7 +1942,7 @@ describe("folded lines", function()
 
       feed('jzfj')
       if multigrid then
-        screen:expect([[
+        screen:expect{grid=[[
         ## grid 1
           [2:---------------------------------------------]|
           [2:---------------------------------------------]|
@@ -1962,7 +1962,9 @@ describe("folded lines", function()
           {1:~                                            }|
         ## grid 3
                                                        |
-        ]])
+        ]], win_viewport={
+          [2] = {win = {id = 1000}, topline = 0, botline = 5, curline = 2, curcol = 0, linecount = 4, sum_scroll_delta = 0};
+        }}
       else
         screen:expect([[
           {5:+--  2 lines: line 1·························}|
@@ -1979,7 +1981,7 @@ describe("folded lines", function()
       feed('kzo<C-Y>')
       funcs.setline(5, 'line 5')
       if multigrid then
-        screen:expect([[
+        screen:expect{grid=[[
         ## grid 1
           [2:---------------------------------------------]|
           [2:---------------------------------------------]|
@@ -1999,7 +2001,9 @@ describe("folded lines", function()
           {1:~                                            }|
         ## grid 3
                                                        |
-        ]])
+        ]], win_viewport={
+          [2] = {win = {id = 1000}, topline = 0, botline = 6, curline = 0, curcol = 0, linecount = 5, sum_scroll_delta = -1};
+        }}
       else
         screen:expect([[
           virt_line above line 1                       |
@@ -2012,6 +2016,398 @@ describe("folded lines", function()
                                                        |
         ]])
       end
+
+      meths.input_mouse('left', 'press', '', multigrid and 2 or 0, 4, 0)
+      eq({
+        column = 1,
+        line = 3,
+        screencol = 1,
+        screenrow = 5,
+        wincol = 1,
+        winid = 1000,
+        winrow = 5,
+      }, funcs.getmousepos())
+
+      meths.buf_set_extmark(0, ns, 1, 0, { virt_lines = {{{"more virt_line below line 2", ""}}} })
+      feed('G<C-E>')
+      if multigrid then
+        screen:expect{grid=[[
+        ## grid 1
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [3:---------------------------------------------]|
+        ## grid 2
+          line 1                                       |
+          line 2                                       |
+          virt_line below line 2                       |
+          more virt_line below line 2                  |
+          {5:+--  2 lines: line 3·························}|
+          ^line 5                                       |
+          {1:~                                            }|
+        ## grid 3
+                                                       |
+        ]], win_viewport={
+          [2] = {win = {id = 1000}, topline = 0, botline = 6, curline = 4, curcol = 0, linecount = 5, sum_scroll_delta = 0};
+        }}
+      else
+        screen:expect([[
+          line 1                                       |
+          line 2                                       |
+          virt_line below line 2                       |
+          more virt_line below line 2                  |
+          {5:+--  2 lines: line 3·························}|
+          ^line 5                                       |
+          {1:~                                            }|
+                                                       |
+        ]])
+      end
+
+      feed('<C-E>')
+      if multigrid then
+        screen:expect{grid=[[
+        ## grid 1
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [3:---------------------------------------------]|
+        ## grid 2
+          line 2                                       |
+          virt_line below line 2                       |
+          more virt_line below line 2                  |
+          {5:+--  2 lines: line 3·························}|
+          ^line 5                                       |
+          {1:~                                            }|
+          {1:~                                            }|
+        ## grid 3
+                                                       |
+        ]], win_viewport={
+          [2] = {win = {id = 1000}, topline = 1, botline = 6, curline = 4, curcol = 0, linecount = 5, sum_scroll_delta = 1};
+        }}
+      else
+        screen:expect([[
+          line 2                                       |
+          virt_line below line 2                       |
+          more virt_line below line 2                  |
+          {5:+--  2 lines: line 3·························}|
+          ^line 5                                       |
+          {1:~                                            }|
+          {1:~                                            }|
+                                                       |
+        ]])
+      end
+
+      feed('<C-E>')
+      if multigrid then
+        screen:expect{grid=[[
+        ## grid 1
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [3:---------------------------------------------]|
+        ## grid 2
+          virt_line below line 2                       |
+          more virt_line below line 2                  |
+          {5:+--  2 lines: line 3·························}|
+          ^line 5                                       |
+          {1:~                                            }|
+          {1:~                                            }|
+          {1:~                                            }|
+        ## grid 3
+                                                       |
+        ]], win_viewport={
+          [2] = {win = {id = 1000}, topline = 2, botline = 6, curline = 4, curcol = 0, linecount = 5, sum_scroll_delta = 2};
+        }}
+      else
+        screen:expect([[
+          virt_line below line 2                       |
+          more virt_line below line 2                  |
+          {5:+--  2 lines: line 3·························}|
+          ^line 5                                       |
+          {1:~                                            }|
+          {1:~                                            }|
+          {1:~                                            }|
+                                                       |
+        ]])
+      end
+
+      feed('<C-E>')
+      if multigrid then
+        screen:expect{grid=[[
+        ## grid 1
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [3:---------------------------------------------]|
+        ## grid 2
+          more virt_line below line 2                  |
+          {5:+--  2 lines: line 3·························}|
+          ^line 5                                       |
+          {1:~                                            }|
+          {1:~                                            }|
+          {1:~                                            }|
+          {1:~                                            }|
+        ## grid 3
+                                                       |
+        ]], win_viewport={
+          [2] = {win = {id = 1000}, topline = 2, botline = 6, curline = 4, curcol = 0, linecount = 5, sum_scroll_delta = 3};
+        }}
+      else
+        screen:expect([[
+          more virt_line below line 2                  |
+          {5:+--  2 lines: line 3·························}|
+          ^line 5                                       |
+          {1:~                                            }|
+          {1:~                                            }|
+          {1:~                                            }|
+          {1:~                                            }|
+                                                       |
+        ]])
+      end
+
+      feed('<C-E>')
+      if multigrid then
+        screen:expect{grid=[[
+        ## grid 1
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [3:---------------------------------------------]|
+        ## grid 2
+          {5:+--  2 lines: line 3·························}|
+          ^line 5                                       |
+          {1:~                                            }|
+          {1:~                                            }|
+          {1:~                                            }|
+          {1:~                                            }|
+          {1:~                                            }|
+        ## grid 3
+                                                       |
+        ]], win_viewport={
+          [2] = {win = {id = 1000}, topline = 2, botline = 6, curline = 4, curcol = 0, linecount = 5, sum_scroll_delta = 4};
+        }}
+      else
+        screen:expect([[
+          {5:+--  2 lines: line 3·························}|
+          ^line 5                                       |
+          {1:~                                            }|
+          {1:~                                            }|
+          {1:~                                            }|
+          {1:~                                            }|
+          {1:~                                            }|
+                                                       |
+        ]])
+      end
+
+      feed('<C-E>')
+      if multigrid then
+        screen:expect{grid=[[
+        ## grid 1
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [3:---------------------------------------------]|
+        ## grid 2
+          ^line 5                                       |
+          {1:~                                            }|
+          {1:~                                            }|
+          {1:~                                            }|
+          {1:~                                            }|
+          {1:~                                            }|
+          {1:~                                            }|
+        ## grid 3
+                                                       |
+        ]], win_viewport={
+          [2] = {win = {id = 1000}, topline = 4, botline = 6, curline = 4, curcol = 0, linecount = 5, sum_scroll_delta = 5};
+        }}
+      else
+        screen:expect([[
+          ^line 5                                       |
+          {1:~                                            }|
+          {1:~                                            }|
+          {1:~                                            }|
+          {1:~                                            }|
+          {1:~                                            }|
+          {1:~                                            }|
+                                                       |
+        ]])
+      end
+
+      feed('3<C-Y>')
+      if multigrid then
+        screen:expect{grid=[[
+        ## grid 1
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [3:---------------------------------------------]|
+        ## grid 2
+          virt_line below line 2                       |
+          more virt_line below line 2                  |
+          {5:+--  2 lines: line 3·························}|
+          ^line 5                                       |
+          {1:~                                            }|
+          {1:~                                            }|
+          {1:~                                            }|
+        ## grid 3
+                                                       |
+        ]], win_viewport={
+          [2] = {win = {id = 1000}, topline = 2, botline = 6, curline = 4, curcol = 0, linecount = 5, sum_scroll_delta = 2};
+        }}
+      else
+        screen:expect([[
+          virt_line below line 2                       |
+          more virt_line below line 2                  |
+          {5:+--  2 lines: line 3·························}|
+          ^line 5                                       |
+          {1:~                                            }|
+          {1:~                                            }|
+          {1:~                                            }|
+                                                       |
+        ]])
+      end
+
+      meths.input_mouse('left', 'press', '3', multigrid and 2 or 0, 3, 0)
+      if multigrid then
+        screen:expect{grid=[[
+        ## grid 1
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [3:---------------------------------------------]|
+        ## grid 2
+          virt_line below line 2                       |
+          more virt_line below line 2                  |
+          {5:+--  2 lines: line 3·························}|
+          ^l{16:ine 5}                                       |
+          {1:~                                            }|
+          {1:~                                            }|
+          {1:~                                            }|
+        ## grid 3
+          {11:-- VISUAL LINE --}                            |
+        ]], win_viewport={
+          [2] = {win = {id = 1000}, topline = 2, botline = 6, curline = 4, curcol = 0, linecount = 5, sum_scroll_delta = 2};
+        }}
+      else
+        screen:expect([[
+          virt_line below line 2                       |
+          more virt_line below line 2                  |
+          {5:+--  2 lines: line 3·························}|
+          ^l{16:ine 5}                                       |
+          {1:~                                            }|
+          {1:~                                            }|
+          {1:~                                            }|
+          {11:-- VISUAL LINE --}                            |
+        ]])
+      end
+
+      meths.input_mouse('left', 'drag', '3', multigrid and 2 or 0, 7, 0)
+      if multigrid then
+        screen:expect{grid=[[
+        ## grid 1
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [3:---------------------------------------------]|
+        ## grid 2
+          more virt_line below line 2                  |
+          {5:+--  2 lines: line 3·························}|
+          ^l{16:ine 5}                                       |
+          {1:~                                            }|
+          {1:~                                            }|
+          {1:~                                            }|
+          {1:~                                            }|
+        ## grid 3
+          {11:-- VISUAL LINE --}                            |
+        ]], win_viewport={
+          [2] = {win = {id = 1000}, topline = 2, botline = 6, curline = 4, curcol = 0, linecount = 5, sum_scroll_delta = 3};
+        }}
+      else
+        screen:expect([[
+          more virt_line below line 2                  |
+          {5:+--  2 lines: line 3·························}|
+          ^l{16:ine 5}                                       |
+          {1:~                                            }|
+          {1:~                                            }|
+          {1:~                                            }|
+          {1:~                                            }|
+          {11:-- VISUAL LINE --}                            |
+        ]])
+      end
+
+      meths.input_mouse('left', 'drag', '3', multigrid and 2 or 0, 7, 5)
+      if multigrid then
+        screen:expect{grid=[[
+        ## grid 1
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [2:---------------------------------------------]|
+          [3:---------------------------------------------]|
+        ## grid 2
+          {5:+--  2 lines: line 3·························}|
+          {16:line }^5                                       |
+          {1:~                                            }|
+          {1:~                                            }|
+          {1:~                                            }|
+          {1:~                                            }|
+          {1:~                                            }|
+        ## grid 3
+          {11:-- VISUAL LINE --}                            |
+        ]], win_viewport={
+          [2] = {win = {id = 1000}, topline = 2, botline = 6, curline = 4, curcol = 5, linecount = 5, sum_scroll_delta = 4};
+        }}
+      else
+        screen:expect([[
+          {5:+--  2 lines: line 3·························}|
+          {16:line }^5                                       |
+          {1:~                                            }|
+          {1:~                                            }|
+          {1:~                                            }|
+          {1:~                                            }|
+          {1:~                                            }|
+          {11:-- VISUAL LINE --}                            |
+        ]])
+      end
     end)
   end
 

test/functional/ui/multigrid_spec.lua

@@ -3343,6 +3343,220 @@ describe('ext_multigrid', function()
     }}
   end)
 
+  it('scroll_delta is approximated reasonably when scrolling many lines #24234', function()
+    command('setlocal number nowrap')
+    command('edit test/functional/fixtures/bigfile.txt')
+    screen:expect{grid=[[
+    ## grid 1
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      {11:test/functional/fixtures/bigfile.txt                 }|
+      [3:-----------------------------------------------------]|
+    ## grid 2
+      {19:    1 }^0000;<control>;Cc;0;BN;;;;;N;NULL;;;;          |
+      {19:    2 }0001;<control>;Cc;0;BN;;;;;N;START OF HEADING;;|
+      {19:    3 }0002;<control>;Cc;0;BN;;;;;N;START OF TEXT;;;; |
+      {19:    4 }0003;<control>;Cc;0;BN;;;;;N;END OF TEXT;;;;   |
+      {19:    5 }0004;<control>;Cc;0;BN;;;;;N;END OF TRANSMISSIO|
+      {19:    6 }0005;<control>;Cc;0;BN;;;;;N;ENQUIRY;;;;       |
+      {19:    7 }0006;<control>;Cc;0;BN;;;;;N;ACKNOWLEDGE;;;;   |
+      {19:    8 }0007;<control>;Cc;0;BN;;;;;N;BELL;;;;          |
+      {19:    9 }0008;<control>;Cc;0;BN;;;;;N;BACKSPACE;;;;     |
+      {19:   10 }0009;<control>;Cc;0;S;;;;;N;CHARACTER TABULATIO|
+      {19:   11 }000A;<control>;Cc;0;B;;;;;N;LINE FEED (LF);;;; |
+      {19:   12 }000B;<control>;Cc;0;S;;;;;N;LINE TABULATION;;;;|
+    ## grid 3
+                                                           |
+    ]], win_viewport={
+      [2] = {win = {id = 1000}, topline = 0, botline = 13, curline = 0, curcol = 0, linecount = 30592, sum_scroll_delta = 0};
+    }}
+    feed('G')
+    screen:expect{grid=[[
+    ## grid 1
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      {11:test/functional/fixtures/bigfile.txt                 }|
+      [3:-----------------------------------------------------]|
+    ## grid 2
+      {19:30581 }E01E8;VARIATION SELECTOR-249;Mn;0;NSM;;;;;N;;;;|
+      {19:30582 }E01E9;VARIATION SELECTOR-250;Mn;0;NSM;;;;;N;;;;|
+      {19:30583 }E01EA;VARIATION SELECTOR-251;Mn;0;NSM;;;;;N;;;;|
+      {19:30584 }E01EB;VARIATION SELECTOR-252;Mn;0;NSM;;;;;N;;;;|
+      {19:30585 }E01EC;VARIATION SELECTOR-253;Mn;0;NSM;;;;;N;;;;|
+      {19:30586 }E01ED;VARIATION SELECTOR-254;Mn;0;NSM;;;;;N;;;;|
+      {19:30587 }E01EE;VARIATION SELECTOR-255;Mn;0;NSM;;;;;N;;;;|
+      {19:30588 }E01EF;VARIATION SELECTOR-256;Mn;0;NSM;;;;;N;;;;|
+      {19:30589 }F0000;<Plane 15 Private Use, First>;Co;0;L;;;;;|
+      {19:30590 }FFFFD;<Plane 15 Private Use, Last>;Co;0;L;;;;;N|
+      {19:30591 }100000;<Plane 16 Private Use, First>;Co;0;L;;;;|
+      {19:30592 }^10FFFD;<Plane 16 Private Use, Last>;Co;0;L;;;;;|
+    ## grid 3
+                                                           |
+    ]], win_viewport={
+      [2] = {win = {id = 1000}, topline = 30580, botline = 30592, curline = 30591, curcol = 0, linecount = 30592, sum_scroll_delta = 30580};
+    }}
+    feed('gg')
+    screen:expect{grid=[[
+    ## grid 1
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      {11:test/functional/fixtures/bigfile.txt                 }|
+      [3:-----------------------------------------------------]|
+    ## grid 2
+      {19:    1 }^0000;<control>;Cc;0;BN;;;;;N;NULL;;;;          |
+      {19:    2 }0001;<control>;Cc;0;BN;;;;;N;START OF HEADING;;|
+      {19:    3 }0002;<control>;Cc;0;BN;;;;;N;START OF TEXT;;;; |
+      {19:    4 }0003;<control>;Cc;0;BN;;;;;N;END OF TEXT;;;;   |
+      {19:    5 }0004;<control>;Cc;0;BN;;;;;N;END OF TRANSMISSIO|
+      {19:    6 }0005;<control>;Cc;0;BN;;;;;N;ENQUIRY;;;;       |
+      {19:    7 }0006;<control>;Cc;0;BN;;;;;N;ACKNOWLEDGE;;;;   |
+      {19:    8 }0007;<control>;Cc;0;BN;;;;;N;BELL;;;;          |
+      {19:    9 }0008;<control>;Cc;0;BN;;;;;N;BACKSPACE;;;;     |
+      {19:   10 }0009;<control>;Cc;0;S;;;;;N;CHARACTER TABULATIO|
+      {19:   11 }000A;<control>;Cc;0;B;;;;;N;LINE FEED (LF);;;; |
+      {19:   12 }000B;<control>;Cc;0;S;;;;;N;LINE TABULATION;;;;|
+    ## grid 3
+                                                           |
+    ]], win_viewport={
+      [2] = {win = {id = 1000}, topline = 0, botline = 13, curline = 0, curcol = 0, linecount = 30592, sum_scroll_delta = 0};
+    }}
+    command('setlocal wrap')
+    screen:expect{grid=[[
+    ## grid 1
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      {11:test/functional/fixtures/bigfile.txt                 }|
+      [3:-----------------------------------------------------]|
+    ## grid 2
+      {19:    1 }^0000;<control>;Cc;0;BN;;;;;N;NULL;;;;          |
+      {19:    2 }0001;<control>;Cc;0;BN;;;;;N;START OF HEADING;;|
+      {19:      };;                                             |
+      {19:    3 }0002;<control>;Cc;0;BN;;;;;N;START OF TEXT;;;; |
+      {19:    4 }0003;<control>;Cc;0;BN;;;;;N;END OF TEXT;;;;   |
+      {19:    5 }0004;<control>;Cc;0;BN;;;;;N;END OF TRANSMISSIO|
+      {19:      }N;;;;                                          |
+      {19:    6 }0005;<control>;Cc;0;BN;;;;;N;ENQUIRY;;;;       |
+      {19:    7 }0006;<control>;Cc;0;BN;;;;;N;ACKNOWLEDGE;;;;   |
+      {19:    8 }0007;<control>;Cc;0;BN;;;;;N;BELL;;;;          |
+      {19:    9 }0008;<control>;Cc;0;BN;;;;;N;BACKSPACE;;;;     |
+      {19:   10 }0009;<control>;Cc;0;S;;;;;N;CHARACTER TABULA{1:@@@}|
+    ## grid 3
+                                                           |
+    ]], win_viewport={
+      [2] = {win = {id = 1000}, topline = 0, botline = 10, curline = 0, curcol = 0, linecount = 30592, sum_scroll_delta = 0};
+    }}
+    feed('G')
+    screen:expect{grid=[[
+    ## grid 1
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      {11:test/functional/fixtures/bigfile.txt                 }|
+      [3:-----------------------------------------------------]|
+    ## grid 2
+      {19:30587 }E01EE;VARIATION SELECTOR-255;Mn;0;NSM;;;;;N;;;;|
+      {19:      };                                              |
+      {19:30588 }E01EF;VARIATION SELECTOR-256;Mn;0;NSM;;;;;N;;;;|
+      {19:      };                                              |
+      {19:30589 }F0000;<Plane 15 Private Use, First>;Co;0;L;;;;;|
+      {19:      }N;;;;;                                         |
+      {19:30590 }FFFFD;<Plane 15 Private Use, Last>;Co;0;L;;;;;N|
+      {19:      };;;;;                                          |
+      {19:30591 }100000;<Plane 16 Private Use, First>;Co;0;L;;;;|
+      {19:      };N;;;;;                                        |
+      {19:30592 }^10FFFD;<Plane 16 Private Use, Last>;Co;0;L;;;;;|
+      {19:      }N;;;;;                                         |
+    ## grid 3
+                                                           |
+    ]], win_viewport={
+      [2] = {win = {id = 1000}, topline = 30586, botline = 30592, curline = 30591, curcol = 0, linecount = 30592, sum_scroll_delta = 30588};
+    }}
+    feed('gg')
+    screen:expect{grid=[[
+    ## grid 1
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      [2:-----------------------------------------------------]|
+      {11:test/functional/fixtures/bigfile.txt                 }|
+      [3:-----------------------------------------------------]|
+    ## grid 2
+      {19:    1 }^0000;<control>;Cc;0;BN;;;;;N;NULL;;;;          |
+      {19:    2 }0001;<control>;Cc;0;BN;;;;;N;START OF HEADING;;|
+      {19:      };;                                             |
+      {19:    3 }0002;<control>;Cc;0;BN;;;;;N;START OF TEXT;;;; |
+      {19:    4 }0003;<control>;Cc;0;BN;;;;;N;END OF TEXT;;;;   |
+      {19:    5 }0004;<control>;Cc;0;BN;;;;;N;END OF TRANSMISSIO|
+      {19:      }N;;;;                                          |
+      {19:    6 }0005;<control>;Cc;0;BN;;;;;N;ENQUIRY;;;;       |
+      {19:    7 }0006;<control>;Cc;0;BN;;;;;N;ACKNOWLEDGE;;;;   |
+      {19:    8 }0007;<control>;Cc;0;BN;;;;;N;BELL;;;;          |
+      {19:    9 }0008;<control>;Cc;0;BN;;;;;N;BACKSPACE;;;;     |
+      {19:   10 }0009;<control>;Cc;0;S;;;;;N;CHARACTER TABULA{1:@@@}|
+    ## grid 3
+                                                           |
+    ]], win_viewport={
+      [2] = {win = {id = 1000}, topline = 0, botline = 10, curline = 0, curcol = 0, linecount = 30592, sum_scroll_delta = 0};
+    }}
+  end)
+
   it('does not crash when dragging mouse across grid boundary', function()
     screen:try_resize(48, 8)
     screen:expect{grid=[[

test/functional/vimscript/screenpos_spec.lua

@@ -1,12 +1,12 @@
 local helpers = require('test.functional.helpers')(after_each)
 local clear, eq, meths = helpers.clear, helpers.eq, helpers.meths
 local command, funcs = helpers.command, helpers.funcs
+local feed = helpers.feed
 
 before_each(clear)
 
 describe('screenpos() function', function()
   it('works in floating window with border', function()
-    local bufnr = meths.create_buf(false, true)
     local opts = {
       relative='editor',
       height=8,
@@ -18,34 +18,56 @@ describe('screenpos() function', function()
       border='none',
       focusable=1
     }
-    local float = meths.open_win(bufnr, false, opts)
+    local float = meths.open_win(meths.create_buf(false, true), false, opts)
     command('redraw')
-    local pos = funcs.screenpos(bufnr, 1, 1)
+    eq({row = 7, col = 9, endcol = 9, curscol = 9}, funcs.screenpos(float, 1, 1))
-    eq(7, pos.row)
-    eq(9, pos.col)
 
     -- only left border
     opts.border = {'', '', '', '', '', '', '', '|'}
     meths.win_set_config(float, opts)
     command('redraw')
-    pos = funcs.screenpos(bufnr, 1, 1)
+    eq({row = 7, col = 10, endcol = 10, curscol = 10}, funcs.screenpos(float, 1, 1))
-    eq(7, pos.row)
-    eq(10, pos.col)
 
     -- only top border
     opts.border = {'', '_', '', '', '', '', '', ''}
     meths.win_set_config(float, opts)
     command('redraw')
-    pos = funcs.screenpos(bufnr, 1, 1)
+    eq({row = 8, col = 9, endcol = 9, curscol = 9}, funcs.screenpos(float, 1, 1))
-    eq(8, pos.row)
-    eq(9, pos.col)
 
     -- both left and top border
     opts.border = 'single'
     meths.win_set_config(float, opts)
     command('redraw')
-    pos = funcs.screenpos(bufnr, 1, 1)
+    eq({row = 8, col = 10, endcol = 10, curscol = 10}, funcs.screenpos(float, 1, 1))
-    eq(8, pos.row)
+  end)
-    eq(10, pos.col)
+
+  it('works for folded line with virt_lines attached to line above', function()
+    meths.buf_set_lines(0, 0, -1, true, {'aaa', 'bbb', 'ccc', 'ddd'})
+    local ns = meths.create_namespace('')
+    meths.buf_set_extmark(0, ns, 0, 0, { virt_lines = {{{'abb'}}, {{'acc'}}, {{'add'}}} })
+    command('2,3fold')
+    eq({row = 5, col = 1, endcol = 1, curscol = 1}, funcs.screenpos(0, 2, 1))
+    eq({row = 5, col = 1, endcol = 1, curscol = 1}, funcs.screenpos(0, 3, 1))
+    eq({row = 6, col = 1, endcol = 1, curscol = 1}, funcs.screenpos(0, 4, 1))
+
+    feed('<C-E>')
+    eq({row = 4, col = 1, endcol = 1, curscol = 1}, funcs.screenpos(0, 2, 1))
+    eq({row = 4, col = 1, endcol = 1, curscol = 1}, funcs.screenpos(0, 3, 1))
+    eq({row = 5, col = 1, endcol = 1, curscol = 1}, funcs.screenpos(0, 4, 1))
+
+    feed('<C-E>')
+    eq({row = 3, col = 1, endcol = 1, curscol = 1}, funcs.screenpos(0, 2, 1))
+    eq({row = 3, col = 1, endcol = 1, curscol = 1}, funcs.screenpos(0, 3, 1))
+    eq({row = 4, col = 1, endcol = 1, curscol = 1}, funcs.screenpos(0, 4, 1))
+
+    feed('<C-E>')
+    eq({row = 2, col = 1, endcol = 1, curscol = 1}, funcs.screenpos(0, 2, 1))
+    eq({row = 2, col = 1, endcol = 1, curscol = 1}, funcs.screenpos(0, 3, 1))
+    eq({row = 3, col = 1, endcol = 1, curscol = 1}, funcs.screenpos(0, 4, 1))
+
+    feed('<C-E>')
+    eq({row = 1, col = 1, endcol = 1, curscol = 1}, funcs.screenpos(0, 2, 1))
+    eq({row = 1, col = 1, endcol = 1, curscol = 1}, funcs.screenpos(0, 3, 1))
+    eq({row = 2, col = 1, endcol = 1, curscol = 1}, funcs.screenpos(0, 4, 1))
   end)
 end)

test/old/testdir/test_cursor_func.vim

@@ -125,7 +125,41 @@ func Test_screenpos()
 	\ 'curscol': wincol + 7,
 	\ 'endcol': wincol + 7}, winid->screenpos(line('$'), 8))
   call assert_equal({'row': 0, 'col': 0, 'curscol': 0, 'endcol': 0},
-        \ winid->screenpos(line('$'), 22))
+	\ winid->screenpos(line('$'), 22))
+
+  1split
+  normal G$
+  redraw
+  " w_skipcol should be subtracted
+  call assert_equal({'row': winrow + 0,
+	\ 'col': wincol + 20 - 1,
+	\ 'curscol': wincol + 20 - 1,
+	\ 'endcol': wincol + 20 - 1},
+	\ screenpos(win_getid(), line('.'), col('.')))
+
+  " w_leftcol should be subtracted
+  setlocal nowrap
+  normal 050zl$
+  call assert_equal({'row': winrow + 0,
+	\ 'col': wincol + 10 - 1,
+	\ 'curscol': wincol + 10 - 1,
+	\ 'endcol': wincol + 10 - 1},
+	\ screenpos(win_getid(), line('.'), col('.')))
+
+  " w_skipcol should only matter for the topline
+" FIXME: This fails because pline_m_win() does not take w_skipcol into
+" account.  If it does, then other tests fail.
+"  wincmd +
+"  setlocal wrap smoothscroll
+"  call setline(line('$') + 1, 'last line')
+"  exe "normal \<C-E>G$"
+"  redraw
+"  call assert_equal({'row': winrow + 1,
+"	\ 'col': wincol + 9 - 1,
+"	\ 'curscol': wincol + 9 - 1,
+"	\ 'endcol': wincol + 9 - 1},
+"	\ screenpos(win_getid(), line('.'), col('.')))
+  close
 
   close
   call assert_equal({}, screenpos(999, 1, 1))
@@ -170,6 +204,19 @@ func Test_screenpos_diff()
   windo diffthis
   wincmd w
   call assert_equal(#{col: 3, row: 7, endcol: 3, curscol: 3}, screenpos(0, 4, 1))
+  call assert_equal(#{col: 3, row: 8, endcol: 3, curscol: 3}, screenpos(0, 5, 1))
+  exe "normal! 3\<C-E>"
+  call assert_equal(#{col: 3, row: 4, endcol: 3, curscol: 3}, screenpos(0, 4, 1))
+  call assert_equal(#{col: 3, row: 5, endcol: 3, curscol: 3}, screenpos(0, 5, 1))
+  exe "normal! \<C-E>"
+  call assert_equal(#{col: 3, row: 3, endcol: 3, curscol: 3}, screenpos(0, 4, 1))
+  call assert_equal(#{col: 3, row: 4, endcol: 3, curscol: 3}, screenpos(0, 5, 1))
+  exe "normal! \<C-E>"
+  call assert_equal(#{col: 3, row: 2, endcol: 3, curscol: 3}, screenpos(0, 4, 1))
+  call assert_equal(#{col: 3, row: 3, endcol: 3, curscol: 3}, screenpos(0, 5, 1))
+  exe "normal! \<C-E>"
+  call assert_equal(#{col: 3, row: 1, endcol: 3, curscol: 3}, screenpos(0, 4, 1))
+  call assert_equal(#{col: 3, row: 2, endcol: 3, curscol: 3}, screenpos(0, 5, 1))
 
   windo diffoff
   bwipe!