feat(api): add nvim_win_text_height (#24236)

It uses the same code as "scroll_delta" of "win_viewport" UI event to
calculate text height, but is more flexible.

10 files changed, 398 insertions, 41 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index d0534731b0..191e9f1546 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -130,9 +130,9 @@ set(NVIM_VERSION_PATCH 0)
 set(NVIM_VERSION_PRERELEASE "-dev") # for package maintainers
 
 # API level
-set(NVIM_API_LEVEL 11)        # Bump this after any API change.
+set(NVIM_API_LEVEL 12)        # Bump this after any API change.
 set(NVIM_API_LEVEL_COMPAT 0)  # Adjust this after a _breaking_ API change.
-set(NVIM_API_PRERELEASE false)
+set(NVIM_API_PRERELEASE true)
 
 # Build-type: RelWithDebInfo
 # /Og means something different in MSVC
diff --git a/runtime/doc/api.txt b/runtime/doc/api.txt
index d96169066c..d128bf0221 100644
--- a/runtime/doc/api.txt
+++ b/runtime/doc/api.txt
@@ -2961,6 +2961,38 @@ nvim_win_set_width({window}, {width})                   *nvim_win_set_width()*
       • {window}  Window handle, or 0 for current window
       • {width}   Width as a count of columns
 
+nvim_win_text_height({window}, {*opts})               *nvim_win_text_height()*
+    Computes the number of screen lines occupied by a range of text in a given
+    window. Works for off-screen text and takes folds into account.
+
+    Diff filler or virtual lines above a line are counted as a part of that
+    line, unless the line is on "start_row" and "start_vcol" is specified.
+
+    Diff filler or virtual lines below the last buffer line are counted in the
+    result when "end_row" is omitted.
+
+    Line indexing is similar to |nvim_buf_get_text()|.
+
+    Parameters: ~
+      • {window}  Window handle, or 0 for current window.
+      • {opts}    Optional parameters:
+                  • start_row: Starting line index, 0-based inclusive. When
+                    omitted start at the very top.
+                  • end_row: Ending line index, 0-based inclusive. When
+                    omitted end at the very bottom.
+                  • start_vcol: Starting virtual column index on "start_row",
+                    0-based inclusive, rounded down to full screen lines. When
+                    omitted include the whole line.
+                  • end_vcol: Ending virtual column index on "end_row",
+                    0-based exclusive, rounded up to full screen lines. When
+                    omitted include the whole line.
+
+    Return: ~
+        The number of screen lines that the range of text occupy.
+
+    See also: ~
+      • |virtcol()| for text width.
+
 
 ==============================================================================
 Win_Config Functions                                          *api-win_config*
diff --git a/runtime/doc/news.txt b/runtime/doc/news.txt
index ac0a57e4d3..51ff0b4468 100644
--- a/runtime/doc/news.txt
+++ b/runtime/doc/news.txt
@@ -99,6 +99,9 @@ The following new APIs and features were added.
 
 • |vim.system()| for running system commands.
 
+• Added |nvim_win_text_height()| to get the number of screen lines occupied by
+  a range of text in a given window.
+
 • |nvim_set_keymap()| and |nvim_del_keymap()| now support abbreviations.
 
 • Implemented LSP inlay hints: |vim.lsp.inlay_hint()|
diff --git a/src/nvim/api/buffer.c b/src/nvim/api/buffer.c
index a0322556b4..3b73237b06 100644
--- a/src/nvim/api/buffer.c
+++ b/src/nvim/api/buffer.c
@@ -1334,27 +1334,6 @@ static void fix_cursor(linenr_T lo, linenr_T hi, linenr_T extra)
   invalidate_botline();
 }
 
-// Normalizes 0-based indexes to buffer line numbers
-static int64_t normalize_index(buf_T *buf, int64_t index, bool end_exclusive, bool *oob)
-{
-  assert(buf->b_ml.ml_line_count > 0);
-  int64_t max_index = buf->b_ml.ml_line_count + (int)end_exclusive - 1;
-  // Fix if < 0
-  index = index < 0 ? max_index + index + 1 : index;
-
-  // Check for oob
-  if (index > max_index) {
-    *oob = true;
-    index = max_index;
-  } else if (index < 0) {
-    *oob = true;
-    index = 0;
-  }
-  // Convert the index to a vim line number
-  index++;
-  return index;
-}
-
 /// Initialise a string array either:
 /// - on the Lua stack (as a table) (if lstate is not NULL)
 /// - as an API array object (if lstate is NULL).
diff --git a/src/nvim/api/keysets.h b/src/nvim/api/keysets.h
index 333b90d7fd..e08186161a 100644
--- a/src/nvim/api/keysets.h
+++ b/src/nvim/api/keysets.h
@@ -172,6 +172,13 @@ typedef struct {
 } Dict(get_highlight);
 
 typedef struct {
+  Object start_row;
+  Object end_row;
+  Object start_vcol;
+  Object end_vcol;
+} Dict(win_text_height);
+
+typedef struct {
   Object buffer;
   Object event;
   Object group;
diff --git a/src/nvim/api/private/helpers.c b/src/nvim/api/private/helpers.c
index f9861c82bf..d0c8ab4dd4 100644
--- a/src/nvim/api/private/helpers.c
+++ b/src/nvim/api/private/helpers.c
@@ -478,6 +478,27 @@ Array string_to_array(const String input, bool crlf)
   return ret;
 }
 
+/// Normalizes 0-based indexes to buffer line numbers.
+int64_t normalize_index(buf_T *buf, int64_t index, bool end_exclusive, bool *oob)
+{
+  assert(buf->b_ml.ml_line_count > 0);
+  int64_t max_index = buf->b_ml.ml_line_count + (int)end_exclusive - 1;
+  // A negative index counts from the bottom.
+  index = index < 0 ? max_index + index + 1 : index;
+
+  // Check for oob and clamp.
+  if (index > max_index) {
+    *oob = true;
+    index = max_index;
+  } else if (index < 0) {
+    *oob = true;
+    index = 0;
+  }
+  // Convert the index to a 1-based line number.
+  index++;
+  return index;
+}
+
 /// Returns a substring of a buffer line
 ///
 /// @param buf          Buffer handle
diff --git a/src/nvim/api/window.c b/src/nvim/api/window.c
index 5fb07ecbc8..07aad2cd88 100644
--- a/src/nvim/api/window.c
+++ b/src/nvim/api/window.c
@@ -8,6 +8,7 @@
 
 #include "nvim/api/private/defs.h"
 #include "nvim/api/private/helpers.h"
+#include "nvim/api/private/validate.h"
 #include "nvim/api/window.h"
 #include "nvim/ascii.h"
 #include "nvim/buffer_defs.h"
@@ -20,6 +21,7 @@
 #include "nvim/lua/executor.h"
 #include "nvim/memline_defs.h"
 #include "nvim/move.h"
+#include "nvim/plines.h"
 #include "nvim/pos.h"
 #include "nvim/types.h"
 #include "nvim/window.h"
@@ -462,3 +464,104 @@ void nvim_win_set_hl_ns(Window window, Integer ns_id, Error *err)
   win->w_hl_needs_update = true;
   redraw_later(win, UPD_NOT_VALID);
 }
+
+/// Computes the number of screen lines occupied by a range of text in a given window.
+/// Works for off-screen text and takes folds into account.
+///
+/// Diff filler or virtual lines above a line are counted as a part of that line,
+/// unless the line is on "start_row" and "start_vcol" is specified.
+///
+/// Diff filler or virtual lines below the last buffer line are counted in the result
+/// when "end_row" is omitted.
+///
+/// Line indexing is similar to |nvim_buf_get_text()|.
+///
+/// @param window  Window handle, or 0 for current window.
+/// @param opts    Optional parameters:
+///                - start_row: Starting line index, 0-based inclusive.
+///                             When omitted start at the very top.
+///                - end_row: Ending line index, 0-based inclusive.
+///                           When omitted end at the very bottom.
+///                - start_vcol: Starting virtual column index on "start_row",
+///                              0-based inclusive, rounded down to full screen lines.
+///                              When omitted include the whole line.
+///                - end_vcol: Ending virtual column index on "end_row",
+///                            0-based exclusive, rounded up to full screen lines.
+///                            When omitted include the whole line.
+/// @return  The number of screen lines that the range of text occupy.
+///
+/// @see |virtcol()| for text width.
+Object nvim_win_text_height(Window window, Dict(win_text_height) *opts, Error *err)
+  FUNC_API_SINCE(12)
+{
+  win_T *const win = find_window_by_handle(window, err);
+  if (!win) {
+    return NIL;
+  }
+  buf_T *const buf = win->w_buffer;
+  const linenr_T line_count = buf->b_ml.ml_line_count;
+
+  linenr_T start_lnum = 1;
+  linenr_T end_lnum = line_count;
+  int64_t start_vcol = -1;
+  int64_t end_vcol = -1;
+
+  bool oob = false;
+
+  if (HAS_KEY(opts->start_row)) {
+    VALIDATE_T("start_row", kObjectTypeInteger, opts->start_row.type, {
+      return NIL;
+    });
+    start_lnum = (linenr_T)normalize_index(buf, opts->start_row.data.integer, false, &oob);
+  }
+
+  if (HAS_KEY(opts->end_row)) {
+    VALIDATE_T("end_row", kObjectTypeInteger, opts->end_row.type, {
+      return NIL;
+    });
+    end_lnum = (linenr_T)normalize_index(buf, opts->end_row.data.integer, false, &oob);
+  }
+
+  VALIDATE(!oob, "%s", "Line index out of bounds", {
+    return NIL;
+  });
+  VALIDATE((start_lnum <= end_lnum), "%s", "'start_row' is higher than 'end_row'", {
+    return NIL;
+  });
+
+  if (HAS_KEY(opts->start_vcol)) {
+    VALIDATE(HAS_KEY(opts->start_row), "%s", "'start_vcol' specified without 'start_row'", {
+      return NIL;
+    });
+    VALIDATE_T("start_vcol", kObjectTypeInteger, opts->start_vcol.type, {
+      return NIL;
+    });
+    start_vcol = opts->start_vcol.data.integer;
+    VALIDATE_RANGE((start_vcol >= 0 && start_vcol <= MAXCOL), "start_vcol", {
+      return NIL;
+    });
+  }
+
+  if (HAS_KEY(opts->end_vcol)) {
+    VALIDATE(HAS_KEY(opts->end_row), "%s", "'end_vcol' specified without 'end_row'", {
+      return NIL;
+    });
+    VALIDATE_T("end_vcol", kObjectTypeInteger, opts->end_vcol.type, {
+      return NIL;
+    });
+    end_vcol = opts->end_vcol.data.integer;
+    VALIDATE_RANGE((end_vcol >= 0 && end_vcol <= MAXCOL), "end_vcol", {
+      return NIL;
+    });
+  }
+
+  if (start_lnum == end_lnum && start_vcol >= 0 && end_vcol >= 0) {
+    VALIDATE((start_vcol <= end_vcol), "%s", "'start_vcol' is higher than 'end_vcol'", {
+      return NIL;
+    });
+  }
+
+  const int64_t res = win_text_height(win, start_lnum, start_vcol, end_lnum, end_vcol)
+                      + (HAS_KEY(opts->end_row) ? 0 : win_get_fill(win, line_count + 1));
+  return INTEGER_OBJ(res);
+}
diff --git a/src/nvim/api/window.h b/src/nvim/api/window.h
index 0f36c12a9f..046d64c1a4 100644
--- a/src/nvim/api/window.h
+++ b/src/nvim/api/window.h
@@ -1,6 +1,7 @@
 #ifndef NVIM_API_WINDOW_H
 #define NVIM_API_WINDOW_H
 
+#include "nvim/api/keysets.h"
 #include "nvim/api/private/defs.h"
 
 #ifdef INCLUDE_GENERATED_DECLARATIONS
diff --git a/src/nvim/plines.c b/src/nvim/plines.c
index 476e5b2b7d..df1414bc8f 100644
--- a/src/nvim/plines.c
+++ b/src/nvim/plines.c
@@ -600,14 +600,14 @@ static int win_nolbr_chartabsize(chartabsize_T *cts, int *headp)
 
 /// Get the number of screen lines a range of text will take in window "wp".
 ///
-/// @param start_lnum  first line number
-/// @param start_vcol  >= 0: virtual column on "start_lnum" where counting starts,
-///                          rounded down to full screen lines
-///                    < 0:  count a full "start_lnum", including filler lines above
-/// @param end_lnum    last line number
-/// @param end_vcol    >= 0: virtual column on "end_lnum" where counting ends,
-///                          rounded up to full screen lines
-///                    < 0:  count a full "end_lnum", not including fillers lines below
+/// @param start_lnum  Starting line number, 1-based inclusive.
+/// @param 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 end_lnum    Ending line number, 1-based inclusive.
+/// @param 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 fillers lines below.
 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)
 {
@@ -620,39 +620,39 @@ int64_t win_text_height(win_T *const wp, const linenr_T start_lnum, const int64_
     width2 = MAX(width2, 0);
   }
 
-  int64_t size = 0;
-  int64_t height_nofill = 0;
+  int64_t height_sum = 0;
+  int64_t height_cur_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_nofill = folded ? 1 : plines_win_nofill(wp, lnum, false);
-    size += height_nofill;
+    height_cur_nofill = folded ? 1 : plines_win_nofill(wp, lnum, false);
+    height_sum += height_cur_nofill;
     const int64_t row_off = (start_vcol < width1 || width2 <= 0)
                             ? 0
                             : 1 + (start_vcol - width1) / width2;
-    size -= MIN(row_off, height_nofill);
+    height_sum -= 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_nofill = folded ? 1 : plines_win_nofill(wp, lnum, false);
-    size += win_get_fill(wp, lnum) + height_nofill;
+    height_cur_nofill = folded ? 1 : plines_win_nofill(wp, lnum, false);
+    height_sum += win_get_fill(wp, lnum) + height_cur_nofill;
     lnum = lnum_next + 1;
   }
 
   if (end_vcol >= 0) {
-    size -= height_nofill;
+    height_sum -= 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;
-    size += MIN(row_off, height_nofill);
+    height_sum += MIN(row_off, height_cur_nofill);
   }
 
-  return size;
+  return height_sum;
 }
diff --git a/test/functional/api/window_spec.lua b/test/functional/api/window_spec.lua
index 55d4ff6b2e..8038a84139 100644
--- a/test/functional/api/window_spec.lua
+++ b/test/functional/api/window_spec.lua
@@ -595,6 +595,217 @@ describe('API/win', function()
     end)
   end)
 
+  describe('text_height', function()
+    it('validation', function()
+      local X = meths.get_vvar('maxcol')
+      insert([[
+        aaa
+        bbb
+        ccc
+        ddd
+        eee]])
+      eq("Invalid window id: 23",
+         pcall_err(meths.win_text_height, 23, {}))
+      eq("Line index out of bounds",
+         pcall_err(curwinmeths.text_height, { start_row = 5 }))
+      eq("Line index out of bounds",
+         pcall_err(curwinmeths.text_height, { start_row = -6 }))
+      eq("Line index out of bounds",
+         pcall_err(curwinmeths.text_height, { end_row = 5 }))
+      eq("Line index out of bounds",
+         pcall_err(curwinmeths.text_height, { end_row = -6 }))
+      eq("'start_row' is higher than 'end_row'",
+         pcall_err(curwinmeths.text_height, { start_row = 3, end_row = 1 }))
+      eq("'start_vcol' specified without 'start_row'",
+         pcall_err(curwinmeths.text_height, { end_row = 2, start_vcol = 0 }))
+      eq("'end_vcol' specified without 'end_row'",
+         pcall_err(curwinmeths.text_height, { start_row = 2, end_vcol = 0 }))
+      eq("Invalid 'start_vcol': out of range",
+         pcall_err(curwinmeths.text_height, { start_row = 2, start_vcol = -1 }))
+      eq("Invalid 'start_vcol': out of range",
+         pcall_err(curwinmeths.text_height, { start_row = 2, start_vcol = X + 1 }))
+      eq("Invalid 'end_vcol': out of range",
+         pcall_err(curwinmeths.text_height, { end_row = 2, end_vcol = -1 }))
+      eq("Invalid 'end_vcol': out of range",
+         pcall_err(curwinmeths.text_height, { end_row = 2, end_vcol = X + 1 }))
+      eq("'start_vcol' is higher than 'end_vcol'",
+         pcall_err(curwinmeths.text_height, { start_row = 2, end_row = 2, start_vcol = 10, end_vcol = 5 }))
+    end)
+
+    it('with two diff windows', function()
+      local X = meths.get_vvar('maxcol')
+      local screen = Screen.new(45, 22)
+      screen:set_default_attr_ids({
+        [0] = {foreground = Screen.colors.Blue1, bold = true};
+        [1] = {foreground = Screen.colors.Blue4, background = Screen.colors.Grey};
+        [2] = {foreground = Screen.colors.Brown};
+        [3] = {foreground = Screen.colors.Blue1, background = Screen.colors.LightCyan1, bold = true};
+        [4] = {background = Screen.colors.LightBlue};
+        [5] = {foreground = Screen.colors.Blue4, background = Screen.colors.LightGrey};
+        [6] = {background = Screen.colors.Plum1};
+        [7] = {background = Screen.colors.Red, bold = true};
+        [8] = {reverse = true};
+        [9] = {bold = true, reverse = true};
+      })
+      screen:attach()
+      exec([[
+        set diffopt+=context:2 number
+        let expr = 'printf("%08d", v:val) .. repeat("!", v:val)'
+        call setline(1, map(range(1, 20) + range(25, 45), expr))
+        vnew
+        call setline(1, map(range(3, 20) + range(28, 50), expr))
+        windo diffthis
+      ]])
+      feed('24gg')
+      screen:expect{grid=[[
+        {1:  }{2:    }{3:----------------}│{1:  }{2:  1 }{4:00000001!       }|
+        {1:  }{2:    }{3:----------------}│{1:  }{2:  2 }{4:00000002!!      }|
+        {1:  }{2:  1 }00000003!!!     │{1:  }{2:  3 }00000003!!!     |
+        {1:  }{2:  2 }00000004!!!!    │{1:  }{2:  4 }00000004!!!!    |
+        {1:+ }{2:  3 }{5:+-- 14 lines: 00}│{1:+ }{2:  5 }{5:+-- 14 lines: 00}|
+        {1:  }{2: 17 }00000019!!!!!!!!│{1:  }{2: 19 }00000019!!!!!!!!|
+        {1:  }{2: 18 }00000020!!!!!!!!│{1:  }{2: 20 }00000020!!!!!!!!|
+        {1:  }{2:    }{3:----------------}│{1:  }{2: 21 }{4:00000025!!!!!!!!}|
+        {1:  }{2:    }{3:----------------}│{1:  }{2: 22 }{4:00000026!!!!!!!!}|
+        {1:  }{2:    }{3:----------------}│{1:  }{2: 23 }{4:00000027!!!!!!!!}|
+        {1:  }{2: 19 }00000028!!!!!!!!│{1:  }{2: 24 }^00000028!!!!!!!!|
+        {1:  }{2: 20 }00000029!!!!!!!!│{1:  }{2: 25 }00000029!!!!!!!!|
+        {1:+ }{2: 21 }{5:+-- 14 lines: 00}│{1:+ }{2: 26 }{5:+-- 14 lines: 00}|
+        {1:  }{2: 35 }00000044!!!!!!!!│{1:  }{2: 40 }00000044!!!!!!!!|
+        {1:  }{2: 36 }00000045!!!!!!!!│{1:  }{2: 41 }00000045!!!!!!!!|
+        {1:  }{2: 37 }{4:00000046!!!!!!!!}│{1:  }{2:    }{3:----------------}|
+        {1:  }{2: 38 }{4:00000047!!!!!!!!}│{1:  }{2:    }{3:----------------}|
+        {1:  }{2: 39 }{4:00000048!!!!!!!!}│{1:  }{2:    }{3:----------------}|
+        {1:  }{2: 40 }{4:00000049!!!!!!!!}│{1:  }{2:    }{3:----------------}|
+        {1:  }{2: 41 }{4:00000050!!!!!!!!}│{1:  }{2:    }{3:----------------}|
+        {8:[No Name] [+]          }{9:[No Name] [+]         }|
+                                                     |
+      ]]}
+      screen:try_resize(45, 3)
+      screen:expect{grid=[[
+        {1:  }{2: 19 }00000028!!!!!!!!│{1:  }{2: 24 }^00000028!!!!!!!!|
+        {8:[No Name] [+]          }{9:[No Name] [+]         }|
+                                                     |
+      ]]}
+      eq(20, meths.win_text_height(1000, {}))
+      eq(20, meths.win_text_height(1001, {}))
+      eq(20, meths.win_text_height(1000, { start_row = 0 }))
+      eq(20, meths.win_text_height(1001, { start_row = 0 }))
+      eq(15, meths.win_text_height(1000, { end_row = -1 }))
+      eq(20, meths.win_text_height(1001, { end_row = -1 }))
+      eq(15, meths.win_text_height(1000, { end_row = 40 }))
+      eq(20, meths.win_text_height(1001, { end_row = 40 }))
+      eq(10, meths.win_text_height(1000, { start_row = 23 }))
+      eq(13, meths.win_text_height(1001, { start_row = 18 }))
+      eq(11, meths.win_text_height(1000, { end_row = 23 }))
+      eq(11, meths.win_text_height(1001, { end_row = 18 }))
+      eq(11, meths.win_text_height(1000, { start_row = 3, end_row = 39 }))
+      eq(11, meths.win_text_height(1001, { start_row = 1, end_row = 34 }))
+      eq(9, meths.win_text_height(1000, { start_row = 4, end_row = 38 }))
+      eq(9, meths.win_text_height(1001, { start_row = 2, end_row = 33 }))
+      eq(9, meths.win_text_height(1000, { start_row = 5, end_row = 37 }))
+      eq(9, meths.win_text_height(1001, { start_row = 3, end_row = 32 }))
+      eq(9, meths.win_text_height(1000, { start_row = 17, end_row = 25 }))
+      eq(9, meths.win_text_height(1001, { start_row = 15, end_row = 20 }))
+      eq(7, meths.win_text_height(1000, { start_row = 18, end_row = 24 }))
+      eq(7, meths.win_text_height(1001, { start_row = 16, end_row = 19 }))
+      eq(6, meths.win_text_height(1000, { start_row = -1 }))
+      eq(5, meths.win_text_height(1000, { start_row = -1, start_vcol = X }))
+      eq(0, meths.win_text_height(1000, { start_row = -1, start_vcol = X, end_row = -1 }))
+      eq(0, meths.win_text_height(1000, { start_row = -1, start_vcol = X, end_row = -1, end_vcol = X }))
+      eq(1, meths.win_text_height(1000, { start_row = -1, start_vcol = 0, end_row = -1, end_vcol = X }))
+      eq(3, meths.win_text_height(1001, { end_row = 0 }))
+      eq(2, meths.win_text_height(1001, { end_row = 0, end_vcol = 0 }))
+      eq(2, meths.win_text_height(1001, { start_row = 0, end_row = 0, end_vcol = 0 }))
+      eq(0, meths.win_text_height(1001, { start_row = 0, start_vcol = 0, end_row = 0, end_vcol = 0 }))
+      eq(1, meths.win_text_height(1001, { start_row = 0, start_vcol = 0, end_row = 0, end_vcol = X }))
+      eq(11, meths.win_text_height(1001, { end_row = 18 }))
+      eq(9, meths.win_text_height(1001, { start_row = 0, start_vcol = 0, end_row = 18 }))
+      eq(10, meths.win_text_height(1001, { end_row = 18, end_vcol = 0 }))
+      eq(8, meths.win_text_height(1001, { start_row = 0, start_vcol = 0, end_row = 18, end_vcol = 0 }))
+    end)
+
+    it('with wrapped lines', function()
+      local X = meths.get_vvar('maxcol')
+      local screen = Screen.new(45, 22)
+      screen:set_default_attr_ids({
+        [0] = {foreground = Screen.colors.Blue1, bold = true};
+        [1] = {foreground = Screen.colors.Brown};
+        [2] = {background = Screen.colors.Yellow};
+      })
+      screen:attach()
+      exec([[
+        set number cpoptions+=n
+        call setline(1, repeat([repeat('foobar-', 36)], 3))
+      ]])
+      local ns = meths.create_namespace('')
+      meths.buf_set_extmark(0, ns, 1, 100, { virt_text = {{('?'):rep(15), 'Search'}}, virt_text_pos = 'inline' })
+      meths.buf_set_extmark(0, ns, 2, 200, { virt_text = {{('!'):rep(75), 'Search'}}, virt_text_pos = 'inline' })
+      screen:expect{grid=[[
+        {1:  1 }^foobar-foobar-foobar-foobar-foobar-foobar|
+        -foobar-foobar-foobar-foobar-foobar-foobar-fo|
+        obar-foobar-foobar-foobar-foobar-foobar-fooba|
+        r-foobar-foobar-foobar-foobar-foobar-foobar-f|
+        oobar-foobar-foobar-foobar-foobar-foobar-foob|
+        ar-foobar-foobar-foobar-foobar-              |
+        {1:  2 }foobar-foobar-foobar-foobar-foobar-foobar|
+        -foobar-foobar-foobar-foobar-foobar-foobar-fo|
+        obar-foobar-fo{2:???????????????}obar-foobar-foob|
+        ar-foobar-foobar-foobar-foobar-foobar-foobar-|
+        foobar-foobar-foobar-foobar-foobar-foobar-foo|
+        bar-foobar-foobar-foobar-foobar-foobar-foobar|
+        -                                            |
+        {1:  3 }foobar-foobar-foobar-foobar-foobar-foobar|
+        -foobar-foobar-foobar-foobar-foobar-foobar-fo|
+        obar-foobar-foobar-foobar-foobar-foobar-fooba|
+        r-foobar-foobar-foobar-foobar-foobar-foobar-f|
+        oobar-foobar-foobar-foob{2:!!!!!!!!!!!!!!!!!!!!!}|
+        {2:!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!}|
+        {2:!!!!!!!!!}ar-foobar-foobar-foobar-foobar-fooba|
+        r-foobar-foobar-                             |
+                                                     |
+      ]]}
+      screen:try_resize(45, 2)
+      screen:expect{grid=[[
+        {1:  1 }^foobar-foobar-foobar-foobar-foobar-foobar|
+                                                     |
+      ]]}
+      eq(21, meths.win_text_height(0, {}))
+      eq(6, meths.win_text_height(0, { start_row = 0, end_row = 0 }))
+      eq(7, meths.win_text_height(0, { start_row = 1, end_row = 1 }))
+      eq(8, meths.win_text_height(0, { start_row = 2, end_row = 2 }))
+      eq(1, meths.win_text_height(0, { start_row = 1, start_vcol = 0, end_row = 1, end_vcol = 41 }))
+      eq(2, meths.win_text_height(0, { start_row = 1, start_vcol = 0, end_row = 1, end_vcol = 42 }))
+      eq(2, meths.win_text_height(0, { start_row = 1, start_vcol = 0, end_row = 1, end_vcol = 86 }))
+      eq(3, meths.win_text_height(0, { start_row = 1, start_vcol = 0, end_row = 1, end_vcol = 87 }))
+      eq(6, meths.win_text_height(0, { start_row = 1, start_vcol = 0, end_row = 1, end_vcol = 266 }))
+      eq(7, meths.win_text_height(0, { start_row = 1, start_vcol = 0, end_row = 1, end_vcol = 267 }))
+      eq(7, meths.win_text_height(0, { start_row = 1, start_vcol = 0, end_row = 1, end_vcol = 311 }))
+      eq(7, meths.win_text_height(0, { start_row = 1, start_vcol = 0, end_row = 1, end_vcol = 312 }))
+      eq(7, meths.win_text_height(0, { start_row = 1, start_vcol = 0, end_row = 1, end_vcol = X }))
+      eq(7, meths.win_text_height(0, { start_row = 1, start_vcol = 40, end_row = 1, end_vcol = X }))
+      eq(6, meths.win_text_height(0, { start_row = 1, start_vcol = 41, end_row = 1, end_vcol = X }))
+      eq(6, meths.win_text_height(0, { start_row = 1, start_vcol = 85, end_row = 1, end_vcol = X }))
+      eq(5, meths.win_text_height(0, { start_row = 1, start_vcol = 86, end_row = 1, end_vcol = X }))
+      eq(2, meths.win_text_height(0, { start_row = 1, start_vcol = 265, end_row = 1, end_vcol = X }))
+      eq(1, meths.win_text_height(0, { start_row = 1, start_vcol = 266, end_row = 1, end_vcol = X }))
+      eq(1, meths.win_text_height(0, { start_row = 1, start_vcol = 310, end_row = 1, end_vcol = X }))
+      eq(0, meths.win_text_height(0, { start_row = 1, start_vcol = 311, end_row = 1, end_vcol = X }))
+      eq(18, meths.win_text_height(0, { start_row = 0, start_vcol = 131 }))
+      eq(19, meths.win_text_height(0, { start_row = 0, start_vcol = 130 }))
+      eq(20, meths.win_text_height(0, { end_row = 2, end_vcol = 311 }))
+      eq(21, meths.win_text_height(0, { end_row = 2, end_vcol = 312 }))
+      eq(17, meths.win_text_height(0, { start_row = 0, start_vcol = 131, end_row = 2, end_vcol = 311 }))
+      eq(19, meths.win_text_height(0, { start_row = 0, start_vcol = 130, end_row = 2, end_vcol = 312 }))
+      eq(16, meths.win_text_height(0, { start_row = 0, start_vcol = 221 }))
+      eq(17, meths.win_text_height(0, { start_row = 0, start_vcol = 220 }))
+      eq(14, meths.win_text_height(0, { end_row = 2, end_vcol = 41 }))
+      eq(15, meths.win_text_height(0, { end_row = 2, end_vcol = 42 }))
+      eq(9, meths.win_text_height(0, { start_row = 0, start_vcol = 221, end_row = 2, end_vcol = 41 }))
+      eq(11, meths.win_text_height(0, { start_row = 0, start_vcol = 220, end_row = 2, end_vcol = 42 }))
+    end)
+  end)
+
   describe('open_win', function()
     it('noautocmd option works', function()
       command('autocmd BufEnter,BufLeave,BufWinEnter * let g:fired = 1')