Merge remote-tracking branch 'upstream/master' into userreguserreg

1 files changed, 386 insertions, 473 deletions

diff --git a/src/nvim/window.c b/src/nvim/window.c
index 05f84b5a91..bcf245ef93 100644
--- a/src/nvim/window.c
+++ b/src/nvim/window.c
@@ -1,12 +1,8 @@
-// This is an open source non-commercial project. Dear PVS-Studio, please check
-// it. PVS-Studio Static Code Analyzer for C, C++ and C#: http://www.viva64.com
-
 #include <assert.h>
 #include <ctype.h>
 #include <inttypes.h>
 #include <limits.h>
 #include <stdbool.h>
-#include <stddef.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -15,7 +11,7 @@
 #include "nvim/api/private/defs.h"
 #include "nvim/api/private/helpers.h"
 #include "nvim/arglist.h"
-#include "nvim/ascii.h"
+#include "nvim/ascii_defs.h"
 #include "nvim/autocmd.h"
 #include "nvim/buffer.h"
 #include "nvim/buffer_defs.h"
@@ -27,7 +23,6 @@
 #include "nvim/edit.h"
 #include "nvim/eval.h"
 #include "nvim/eval/typval.h"
-#include "nvim/eval/typval_defs.h"
 #include "nvim/eval/vars.h"
 #include "nvim/eval/window.h"
 #include "nvim/ex_cmds.h"
@@ -38,6 +33,7 @@
 #include "nvim/file_search.h"
 #include "nvim/fileio.h"
 #include "nvim/fold.h"
+#include "nvim/func_attr.h"
 #include "nvim/garray.h"
 #include "nvim/getchar.h"
 #include "nvim/gettext.h"
@@ -45,40 +41,39 @@
 #include "nvim/grid.h"
 #include "nvim/hashtab.h"
 #include "nvim/keycodes.h"
-#include "nvim/macros.h"
+#include "nvim/macros_defs.h"
 #include "nvim/main.h"
-#include "nvim/map.h"
+#include "nvim/map_defs.h"
 #include "nvim/mapping.h"  // IWYU pragma: keep (langmap_adjust_mb)
 #include "nvim/mark.h"
 #include "nvim/match.h"
 #include "nvim/mbyte.h"
-#include "nvim/memline_defs.h"
 #include "nvim/memory.h"
 #include "nvim/message.h"
 #include "nvim/mouse.h"
 #include "nvim/move.h"
 #include "nvim/normal.h"
 #include "nvim/option.h"
-#include "nvim/optionstr.h"
-#include "nvim/os/os.h"
-#include "nvim/os/os_defs.h"
+#include "nvim/option_defs.h"
+#include "nvim/option_vars.h"
+#include "nvim/os/fs.h"
 #include "nvim/path.h"
 #include "nvim/plines.h"
-#include "nvim/pos.h"
+#include "nvim/pos_defs.h"
 #include "nvim/quickfix.h"
-#include "nvim/screen.h"
 #include "nvim/search.h"
 #include "nvim/state.h"
 #include "nvim/statusline.h"
 #include "nvim/strings.h"
 #include "nvim/syntax.h"
 #include "nvim/terminal.h"
-#include "nvim/types.h"
+#include "nvim/types_defs.h"
 #include "nvim/ui.h"
 #include "nvim/ui_compositor.h"
 #include "nvim/undo.h"
-#include "nvim/vim.h"
+#include "nvim/vim_defs.h"
 #include "nvim/window.h"
+#include "nvim/winfloat.h"
 
 #ifdef INCLUDE_GENERATED_DECLARATIONS
 # include "window.c.generated.h"
@@ -97,7 +92,7 @@ typedef enum {
   WEE_TRIGGER_LEAVE_AUTOCMDS = 0x10,
 } wee_flags_T;
 
-static char e_cannot_split_window_when_closing_buffer[]
+static const char e_cannot_split_window_when_closing_buffer[]
   = N_("E1159: Cannot split a window when closing the buffer");
 
 static char *m_onlyone = N_("Already only one window");
@@ -140,15 +135,41 @@ win_T *prevwin_curwin(void)
   return is_in_cmdwin() && prevwin != NULL ? prevwin : curwin;
 }
 
+/// If the 'switchbuf' option contains "useopen" or "usetab", then try to jump
+/// to a window containing "buf".
+/// Returns the pointer to the window that was jumped to or NULL.
+win_T *swbuf_goto_win_with_buf(buf_T *buf)
+{
+  win_T *wp = NULL;
+
+  if (buf == NULL) {
+    return wp;
+  }
+
+  // If 'switchbuf' contains "useopen": jump to first window in the current
+  // tab page containing "buf" if one exists.
+  if (swb_flags & SWB_USEOPEN) {
+    wp = buf_jump_open_win(buf);
+  }
+
+  // If 'switchbuf' contains "usetab": jump to first window in any tab page
+  // containing "buf" if one exists.
+  if (wp == NULL && (swb_flags & SWB_USETAB)) {
+    wp = buf_jump_open_tab(buf);
+  }
+
+  return wp;
+}
+
 /// all CTRL-W window commands are handled here, called from normal_cmd().
 ///
 /// @param xchar  extra char from ":wincmd gx" or NUL
-void do_window(int nchar, long Prenum, int xchar)
+void do_window(int nchar, int Prenum, int xchar)
 {
   int type = FIND_DEFINE;
   char cbuf[40];
 
-  long Prenum1 = Prenum == 0 ? 1 : Prenum;
+  int Prenum1 = Prenum == 0 ? 1 : Prenum;
 
 #define CHECK_CMDWIN \
   do { \
@@ -170,7 +191,7 @@ void do_window(int nchar, long Prenum, int xchar)
     if (bt_quickfix(curbuf)) {
       goto newwindow;
     }
-    (void)win_split((int)Prenum, 0);
+    (void)win_split(Prenum, 0);
     break;
 
   // split current window in two parts, vertically
@@ -183,7 +204,7 @@ void do_window(int nchar, long Prenum, int xchar)
     if (bt_quickfix(curbuf)) {
       goto newwindow;
     }
-    (void)win_split((int)Prenum, WSP_VERT);
+    (void)win_split(Prenum, WSP_VERT);
     break;
 
   // split current window and edit alternate file
@@ -192,7 +213,7 @@ void do_window(int nchar, long Prenum, int xchar)
     CHECK_CMDWIN;
     reset_VIsual_and_resel();  // stop Visual mode
 
-    if (buflist_findnr(Prenum == 0 ? curwin->w_alt_fnum : (int)Prenum) == NULL) {
+    if (buflist_findnr(Prenum == 0 ? curwin->w_alt_fnum : Prenum) == NULL) {
       if (Prenum == 0) {
         emsg(_(e_noalt));
       } else {
@@ -202,8 +223,8 @@ void do_window(int nchar, long Prenum, int xchar)
     }
 
     if (!curbuf_locked() && win_split(0, 0) == OK) {
-      (void)buflist_getfile(Prenum == 0 ? curwin->w_alt_fnum : (int)Prenum,
-                            (linenr_T)0, GETF_ALT, false);
+      (void)buflist_getfile(Prenum == 0 ? curwin->w_alt_fnum : Prenum,
+                            0, GETF_ALT, false);
     }
     break;
 
@@ -355,17 +376,16 @@ newwindow:
   case 'T':
     CHECK_CMDWIN;
     if (one_window(curwin)) {
-      msg(_(m_onlyone));
+      msg(_(m_onlyone), 0);
     } else {
       tabpage_T *oldtab = curtab;
-      tabpage_T *newtab;
 
       // First create a new tab with the window, then go back to
       // the old tab and close the window there.
       win_T *wp = curwin;
-      if (win_new_tabpage((int)Prenum, NULL) == OK
+      if (win_new_tabpage(Prenum, NULL) == OK
           && valid_tabpage(oldtab)) {
-        newtab = curtab;
+        tabpage_T *newtab = curtab;
         goto_tabpage_tp(oldtab, true, true);
         if (curwin == wp) {
           win_close(curwin, false, false);
@@ -412,14 +432,14 @@ newwindow:
   case 'r':
     CHECK_CMDWIN;
     reset_VIsual_and_resel();  // stop Visual mode
-    win_rotate(false, (int)Prenum1);  // downwards
+    win_rotate(false, Prenum1);  // downwards
     break;
 
   // rotate windows upwards
   case 'R':
     CHECK_CMDWIN;
     reset_VIsual_and_resel();  // stop Visual mode
-    win_rotate(true, (int)Prenum1);  // upwards
+    win_rotate(true, Prenum1);  // upwards
     break;
 
   // move window to the very top/bottom/left/right
@@ -428,7 +448,7 @@ newwindow:
   case 'H':
   case 'L':
     CHECK_CMDWIN;
-    win_totop((int)Prenum,
+    win_totop(Prenum,
               ((nchar == 'H' || nchar == 'L') ? WSP_VERT : 0)
               | ((nchar == 'H' || nchar == 'K') ? WSP_TOP : WSP_BOT));
     break;
@@ -442,40 +462,40 @@ newwindow:
 
   // increase current window height
   case '+':
-    win_setheight(curwin->w_height + (int)Prenum1);
+    win_setheight(curwin->w_height + Prenum1);
     break;
 
   // decrease current window height
   case '-':
-    win_setheight(curwin->w_height - (int)Prenum1);
+    win_setheight(curwin->w_height - Prenum1);
     break;
 
   // set current window height
   case Ctrl__:
   case '_':
-    win_setheight(Prenum ? (int)Prenum : Rows - 1);
+    win_setheight(Prenum ? Prenum : Rows - 1);
     break;
 
   // increase current window width
   case '>':
-    win_setwidth(curwin->w_width + (int)Prenum1);
+    win_setwidth(curwin->w_width + Prenum1);
     break;
 
   // decrease current window width
   case '<':
-    win_setwidth(curwin->w_width - (int)Prenum1);
+    win_setwidth(curwin->w_width - Prenum1);
     break;
 
   // set current window width
   case '|':
-    win_setwidth(Prenum != 0 ? (int)Prenum : Columns);
+    win_setwidth(Prenum != 0 ? Prenum : Columns);
     break;
 
   // jump to tag and split window if tag exists (in preview window)
   case '}':
     CHECK_CMDWIN;
     if (Prenum) {
-      g_do_tagpreview = (int)Prenum;
+      g_do_tagpreview = Prenum;
     } else {
       g_do_tagpreview = (int)p_pvh;
     }
@@ -485,7 +505,7 @@ newwindow:
     CHECK_CMDWIN;
     // Keep visual mode, can select words to use as a tag.
     if (Prenum) {
-      postponed_split = (int)Prenum;
+      postponed_split = Prenum;
     } else {
       postponed_split = -1;
     }
@@ -506,6 +526,9 @@ newwindow:
   case Ctrl_F: {
 wingotofile:
     CHECK_CMDWIN;
+    if (check_text_or_curbuf_locked(NULL)) {
+      break;
+    }
 
     linenr_T lnum = -1;
     char *ptr = grab_file_name(Prenum1, &lnum);
@@ -513,18 +536,31 @@ wingotofile:
       tabpage_T *oldtab = curtab;
       win_T *oldwin = curwin;
       setpcmark();
-      if (win_split(0, 0) == OK) {
+
+      // If 'switchbuf' is set to 'useopen' or 'usetab' and the
+      // file is already opened in a window, then jump to it.
+      win_T *wp = NULL;
+      if ((swb_flags & (SWB_USEOPEN | SWB_USETAB))
+          && cmdmod.cmod_tab == 0) {
+        wp = swbuf_goto_win_with_buf(buflist_findname_exp(ptr));
+      }
+
+      if (wp == NULL && win_split(0, 0) == OK) {
         RESET_BINDING(curwin);
         if (do_ecmd(0, ptr, NULL, NULL, ECMD_LASTL, ECMD_HIDE, NULL) == FAIL) {
           // Failed to open the file, close the window opened for it.
           win_close(curwin, false, false);
           goto_tabpage_win(oldtab, oldwin);
-        } else if (nchar == 'F' && lnum >= 0) {
-          curwin->w_cursor.lnum = lnum;
-          check_cursor_lnum();
-          beginline(BL_SOL | BL_FIX);
+        } else {
+          wp = curwin;
         }
       }
+
+      if (wp != NULL && nchar == 'F' && lnum >= 0) {
+        curwin->w_cursor.lnum = lnum;
+        check_cursor_lnum(curwin);
+        beginline(BL_SOL | BL_FIX);
+      }
       xfree(ptr);
     }
     break;
@@ -546,7 +582,7 @@ wingotofile:
     }
 
     // Make a copy, if the line was changed it will be freed.
-    ptr = xstrnsave(ptr, len);
+    ptr = xmemdupz(ptr, len);
 
     find_pattern_in_path(ptr, 0, len, true, Prenum == 0,
                          type, Prenum1, ACTION_SPLIT, 1, MAXLNUM);
@@ -581,7 +617,7 @@ wingotofile:
     case '}':
       xchar = Ctrl_RSB;
       if (Prenum) {
-        g_do_tagpreview = (int)Prenum;
+        g_do_tagpreview = Prenum;
       } else {
         g_do_tagpreview = (int)p_pvh;
       }
@@ -590,7 +626,7 @@ wingotofile:
     case Ctrl_RSB:
       // Keep visual mode, can select words to use as a tag.
       if (Prenum) {
-        postponed_split = (int)Prenum;
+        postponed_split = Prenum;
       } else {
         postponed_split = -1;
       }
@@ -608,11 +644,11 @@ wingotofile:
       goto wingotofile;
 
     case 't':                       // CTRL-W gt: go to next tab page
-      goto_tabpage((int)Prenum);
+      goto_tabpage(Prenum);
       break;
 
     case 'T':                       // CTRL-W gT: go to previous tab page
-      goto_tabpage(-(int)Prenum1);
+      goto_tabpage(-Prenum1);
       break;
 
     case TAB:                       // CTRL-W g<Tab>: go to last used tab page
@@ -658,17 +694,13 @@ static void cmd_with_count(char *cmd, char *bufp, size_t bufsize, int64_t Prenum
   }
 }
 
-void win_set_buf(Window window, Buffer buffer, bool noautocmd, Error *err)
+void win_set_buf(win_T *win, buf_T *buf, bool noautocmd, Error *err)
+  FUNC_ATTR_NONNULL_ALL
 {
-  win_T *win = find_window_by_handle(window, err);
-  buf_T *buf = find_buffer_by_handle(buffer, err);
-
-  if (!win || !buf) {
-    return;
-  }
-
   tabpage_T *tab = win_find_tabpage(win);
 
+  // no redrawing and don't set the window title
+  RedrawingDisabled++;
   if (noautocmd) {
     block_autocmds();
   }
@@ -678,7 +710,7 @@ void win_set_buf(Window window, Buffer buffer, bool noautocmd, Error *err)
     api_set_error(err,
                   kErrorTypeException,
                   "Failed to switch to window %d",
-                  window);
+                  win->handle);
   }
 
   try_start();
@@ -687,7 +719,7 @@ void win_set_buf(Window window, Buffer buffer, bool noautocmd, Error *err)
     api_set_error(err,
                   kErrorTypeException,
                   "Failed to set buffer %d",
-                  buffer);
+                  buf->handle);
   }
 
   // If window is not current, state logic will not validate its cursor.
@@ -698,210 +730,13 @@ void win_set_buf(Window window, Buffer buffer, bool noautocmd, Error *err)
   if (noautocmd) {
     unblock_autocmds();
   }
-}
-
-/// Create a new float.
-///
-/// @param wp      if NULL, allocate a new window, otherwise turn existing window into a float.
-///                It must then already belong to the current tabpage!
-/// @param last    make the window the last one in the window list.
-///                Only used when allocating the autocommand window.
-/// @param config  must already have been validated!
-win_T *win_new_float(win_T *wp, bool last, FloatConfig fconfig, Error *err)
-{
-  if (wp == NULL) {
-    wp = win_alloc(last ? lastwin : lastwin_nofloating(), false);
-    win_init(wp, curwin, 0);
-  } else {
-    assert(!last);
-    assert(!wp->w_floating);
-    if (firstwin == wp && lastwin_nofloating() == wp) {
-      // last non-float
-      api_set_error(err, kErrorTypeException,
-                    "Cannot change last window into float");
-      return NULL;
-    } else if (!win_valid(wp)) {
-      api_set_error(err, kErrorTypeException,
-                    "Cannot change window from different tabpage into float");
-      return NULL;
-    }
-    int dir;
-    winframe_remove(wp, &dir, NULL);
-    XFREE_CLEAR(wp->w_frame);
-    (void)win_comp_pos();  // recompute window positions
-    win_remove(wp, NULL);
-    win_append(lastwin_nofloating(), wp);
-  }
-  wp->w_floating = true;
-  wp->w_status_height = 0;
-  wp->w_winbar_height = 0;
-  wp->w_hsep_height = 0;
-  wp->w_vsep_width = 0;
-
-  win_config_float(wp, fconfig);
-  win_set_inner_size(wp, true);
-  wp->w_pos_changed = true;
-  redraw_later(wp, UPD_VALID);
-  return wp;
-}
-
-void win_set_minimal_style(win_T *wp)
-{
-  wp->w_p_nu = false;
-  wp->w_p_rnu = false;
-  wp->w_p_cul = false;
-  wp->w_p_cuc = false;
-  wp->w_p_spell = false;
-  wp->w_p_list = false;
-
-  // Hide EOB region: use " " fillchar and cleared highlighting
-  if (wp->w_p_fcs_chars.eob != ' ') {
-    char *old = wp->w_p_fcs;
-    wp->w_p_fcs = ((*old == NUL)
-                   ? xstrdup("eob: ")
-                   : concat_str(old, ",eob: "));
-    free_string_option(old);
-  }
-
-  // TODO(bfredl): this could use a highlight namespace directly,
-  // and avoid peculiarities around window options
-  char *old = wp->w_p_winhl;
-  wp->w_p_winhl = ((*old == NUL)
-                   ? xstrdup("EndOfBuffer:")
-                   : concat_str(old, ",EndOfBuffer:"));
-  free_string_option(old);
-  parse_winhl_opt(wp);
-
-  // signcolumn: use 'auto'
-  if (wp->w_p_scl[0] != 'a' || strlen(wp->w_p_scl) >= 8) {
-    free_string_option(wp->w_p_scl);
-    wp->w_p_scl = xstrdup("auto");
-  }
-
-  // foldcolumn: use '0'
-  if (wp->w_p_fdc[0] != '0') {
-    free_string_option(wp->w_p_fdc);
-    wp->w_p_fdc = xstrdup("0");
-  }
-
-  // colorcolumn: cleared
-  if (wp->w_p_cc != NULL && *wp->w_p_cc != NUL) {
-    free_string_option(wp->w_p_cc);
-    wp->w_p_cc = xstrdup("");
-  }
-
-  // statuscolumn: cleared
-  if (wp->w_p_stc != NULL && *wp->w_p_stc != NUL) {
-    free_string_option(wp->w_p_stc);
-    wp->w_p_stc = xstrdup("");
-  }
-}
-
-void win_config_float(win_T *wp, FloatConfig fconfig)
-{
-  wp->w_width = MAX(fconfig.width, 1);
-  wp->w_height = MAX(fconfig.height, 1);
-
-  if (fconfig.relative == kFloatRelativeCursor) {
-    fconfig.relative = kFloatRelativeWindow;
-    fconfig.row += curwin->w_wrow;
-    fconfig.col += curwin->w_wcol;
-    fconfig.window = curwin->handle;
-  } else if (fconfig.relative == kFloatRelativeMouse) {
-    int row = mouse_row, col = mouse_col, grid = mouse_grid;
-    win_T *mouse_win = mouse_find_win(&grid, &row, &col);
-    if (mouse_win != NULL) {
-      fconfig.relative = kFloatRelativeWindow;
-      fconfig.row += row;
-      fconfig.col += col;
-      fconfig.window = mouse_win->handle;
-    }
-  }
-
-  bool change_external = fconfig.external != wp->w_float_config.external;
-  bool change_border = (fconfig.border != wp->w_float_config.border
-                        || memcmp(fconfig.border_hl_ids,
-                                  wp->w_float_config.border_hl_ids,
-                                  sizeof fconfig.border_hl_ids) != 0);
-
-  wp->w_float_config = fconfig;
-
-  bool has_border = wp->w_floating && wp->w_float_config.border;
-  for (int i = 0; i < 4; i++) {
-    int new_adj = has_border && wp->w_float_config.border_chars[2 * i + 1][0];
-    if (new_adj != wp->w_border_adj[i]) {
-      change_border = true;
-      wp->w_border_adj[i] = new_adj;
-    }
-  }
-
-  if (!ui_has(kUIMultigrid)) {
-    wp->w_height = MIN(wp->w_height, Rows - 1 - win_border_height(wp));
-    wp->w_width = MIN(wp->w_width, Columns - win_border_width(wp));
-  }
-
-  win_set_inner_size(wp, true);
-  must_redraw = MAX(must_redraw, UPD_VALID);
-
-  wp->w_pos_changed = true;
-  if (change_external || change_border) {
-    wp->w_hl_needs_update = true;
-    redraw_later(wp, UPD_NOT_VALID);
-  }
-
-  // compute initial position
-  if (wp->w_float_config.relative == kFloatRelativeWindow) {
-    int row = (int)wp->w_float_config.row;
-    int col = (int)wp->w_float_config.col;
-    Error dummy = ERROR_INIT;
-    win_T *parent = find_window_by_handle(wp->w_float_config.window, &dummy);
-    if (parent) {
-      row += parent->w_winrow;
-      col += parent->w_wincol;
-      ScreenGrid *grid = &parent->w_grid;
-      int row_off = 0, col_off = 0;
-      grid_adjust(&grid, &row_off, &col_off);
-      row += row_off;
-      col += col_off;
-      if (wp->w_float_config.bufpos.lnum >= 0) {
-        pos_T pos = { wp->w_float_config.bufpos.lnum + 1,
-                      wp->w_float_config.bufpos.col, 0 };
-        int trow, tcol, tcolc, tcole;
-        textpos2screenpos(parent, &pos, &trow, &tcol, &tcolc, &tcole, true);
-        row += trow - 1;
-        col += tcol - 1;
-      }
-    }
-    api_clear_error(&dummy);
-    wp->w_winrow = row;
-    wp->w_wincol = col;
-  } else {
-    wp->w_winrow = (int)fconfig.row;
-    wp->w_wincol = (int)fconfig.col;
-  }
-
-  // changing border style while keeping border only requires redrawing border
-  if (fconfig.border) {
-    wp->w_redr_border = true;
-    redraw_later(wp, UPD_VALID);
-  }
-}
-
-void win_check_anchored_floats(win_T *win)
-{
-  for (win_T *wp = lastwin; wp && wp->w_floating; wp = wp->w_prev) {
-    // float might be anchored to moved window
-    if (wp->w_float_config.relative == kFloatRelativeWindow
-        && wp->w_float_config.window == win->handle) {
-      wp->w_pos_changed = true;
-    }
-  }
+  RedrawingDisabled--;
 }
 
 /// Return the number of fold columns to display
 int win_fdccol_count(win_T *wp)
 {
-  const char *fdc = (const char *)wp->w_p_fdc;
+  const char *fdc = wp->w_p_fdc;
 
   // auto:<NUM>
   if (strncmp(fdc, "auto", 4) == 0) {
@@ -928,7 +763,13 @@ void ui_ext_win_position(win_T *wp, bool validate)
     if (c.relative == kFloatRelativeWindow) {
       Error dummy = ERROR_INIT;
       win_T *win = find_window_by_handle(c.window, &dummy);
-      if (win) {
+      api_clear_error(&dummy);
+      if (win != NULL) {
+        // When a floating window is anchored to another window,
+        // update the position of its anchored window first.
+        if (win->w_pos_changed && win->w_grid_alloc.chars != NULL && win_valid(win)) {
+          ui_ext_win_position(win, validate);
+        }
         grid = &win->w_grid;
         int row_off = 0, col_off = 0;
         grid_adjust(&grid, &row_off, &col_off);
@@ -942,15 +783,18 @@ void ui_ext_win_position(win_T *wp, bool validate)
           col += tcol - 1;
         }
       }
-      api_clear_error(&dummy);
     }
 
     wp->w_grid_alloc.zindex = wp->w_float_config.zindex;
     if (ui_has(kUIMultigrid)) {
       String anchor = cstr_as_string((char *)float_anchor_str[c.anchor]);
-      ui_call_win_float_pos(wp->w_grid_alloc.handle, wp->handle, anchor,
-                            grid->handle, row, col, c.focusable,
-                            wp->w_grid_alloc.zindex);
+      if (!c.hide) {
+        ui_call_win_float_pos(wp->w_grid_alloc.handle, wp->handle, anchor,
+                              grid->handle, row, col, c.focusable,
+                              wp->w_grid_alloc.zindex);
+      } else {
+        ui_call_win_hide(wp->w_grid_alloc.handle);
+      }
     } else {
       bool valid = (wp->w_redr_type == 0);
       if (!valid && !validate) {
@@ -967,16 +811,23 @@ void ui_ext_win_position(win_T *wp, bool validate)
       comp_row += grid->comp_row;
       comp_col += grid->comp_col;
       comp_row = MAX(MIN(comp_row, Rows - wp->w_height_outer - (p_ch > 0 ? 1 : 0)), 0);
-      comp_col = MAX(MIN(comp_col, Columns - wp->w_width_outer), 0);
+      if (!c.fixed || east) {
+        comp_col = MAX(MIN(comp_col, Columns - wp->w_width_outer), 0);
+      }
       wp->w_winrow = comp_row;
       wp->w_wincol = comp_col;
-      ui_comp_put_grid(&wp->w_grid_alloc, comp_row, comp_col,
-                       wp->w_height_outer, wp->w_width_outer, valid, false);
-      ui_check_cursor_grid(wp->w_grid_alloc.handle);
-      wp->w_grid_alloc.focusable = wp->w_float_config.focusable;
-      if (!valid) {
-        wp->w_grid_alloc.valid = false;
-        redraw_later(wp, UPD_NOT_VALID);
+
+      if (!c.hide) {
+        ui_comp_put_grid(&wp->w_grid_alloc, comp_row, comp_col,
+                         wp->w_height_outer, wp->w_width_outer, valid, false);
+        ui_check_cursor_grid(wp->w_grid_alloc.handle);
+        wp->w_grid_alloc.focusable = wp->w_float_config.focusable;
+        if (!valid) {
+          wp->w_grid_alloc.valid = false;
+          redraw_later(wp, UPD_NOT_VALID);
+        }
+      } else {
+        ui_comp_remove_grid(&wp->w_grid_alloc);
       }
     }
   } else {
@@ -986,22 +837,63 @@ void ui_ext_win_position(win_T *wp, bool validate)
 
 void ui_ext_win_viewport(win_T *wp)
 {
-  if ((wp == curwin || ui_has(kUIMultigrid)) && wp->w_viewport_invalid) {
-    int botline = wp->w_botline;
-    int line_count = wp->w_buffer->b_ml.ml_line_count;
-    if (botline == line_count + 1 && wp->w_empty_rows == 0) {
+  // 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) {
+    const linenr_T line_count = wp->w_buffer->b_ml.ml_line_count;
+    // Avoid ml_get errors when producing "scroll_delta".
+    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;
     }
-    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);
+    ui_call_win_viewport(wp->w_grid_alloc.handle, wp->handle, wp->w_topline - 1, ev_botline,
+                         wp->w_cursor.lnum - 1, wp->w_cursor.col, line_count, 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;
   }
 }
 
-/// If "split_disallowed" is set given an error and return FAIL.
+/// If "split_disallowed" is set give an error and return FAIL.
 /// Otherwise return OK.
 static int check_split_disallowed(void)
 {
@@ -1058,10 +950,10 @@ int win_split(int size, int flags)
   return win_split_ins(size, flags, NULL, 0);
 }
 
-// When "new_wp" is NULL: split the current window in two.
-// When "new_wp" is not NULL: insert this window at the far
-// top/left/right/bottom.
-// return FAIL for failure, OK otherwise
+/// When "new_wp" is NULL: split the current window in two.
+/// When "new_wp" is not NULL: insert this window at the far
+/// top/left/right/bottom.
+/// @return  FAIL for failure, OK otherwise
 int win_split_ins(int size, int flags, win_T *new_wp, int dir)
 {
   win_T *wp = new_wp;
@@ -1435,7 +1327,7 @@ int win_split_ins(int size, int flags, win_T *new_wp, int dir)
     frame_fix_width(oldwin);
     frame_fix_width(wp);
   } else {
-    bool is_stl_global = global_stl_height() > 0;
+    const bool is_stl_global = global_stl_height() > 0;
     // width and column of new window is same as current window
     if (flags & (WSP_TOP | WSP_BOT)) {
       wp->w_wincol = 0;
@@ -1451,6 +1343,7 @@ int win_split_ins(int size, int flags, win_T *new_wp, int dir)
     // "new_size" of the current window goes to the new window, use
     // one row for the status line
     win_new_height(wp, new_size);
+    const int old_status_height = oldwin->w_status_height;
     if (before) {
       wp->w_hsep_height = is_stl_global ? 1 : 0;
     } else {
@@ -1459,15 +1352,19 @@ int win_split_ins(int size, int flags, win_T *new_wp, int dir)
     }
     if (flags & (WSP_TOP | WSP_BOT)) {
       int new_fr_height = curfrp->fr_height - new_size;
-
-      if (!((flags & WSP_BOT) && p_ls == 0) && !is_stl_global) {
-        new_fr_height -= STATUS_HEIGHT;
-      } else if (is_stl_global) {
+      if (is_stl_global) {
         if (flags & WSP_BOT) {
           frame_add_hsep(curfrp);
         } else {
           new_fr_height -= 1;
         }
+      } else {
+        if (!((flags & WSP_BOT) && p_ls == 0)) {
+          new_fr_height -= STATUS_HEIGHT;
+        }
+        if (flags & WSP_BOT) {
+          frame_add_statusline(curfrp);
+        }
       }
       frame_new_height(curfrp, new_fr_height, flags & WSP_TOP, false);
     } else {
@@ -1476,7 +1373,6 @@ int win_split_ins(int size, int flags, win_T *new_wp, int dir)
 
     if (before) {       // new window above current one
       wp->w_winrow = oldwin->w_winrow;
-
       if (is_stl_global) {
         wp->w_status_height = 0;
         oldwin->w_winrow += wp->w_height + 1;
@@ -1490,15 +1386,12 @@ int win_split_ins(int size, int flags, win_T *new_wp, int dir)
         wp->w_status_height = 0;
       } else {
         wp->w_winrow = oldwin->w_winrow + oldwin->w_height + STATUS_HEIGHT;
-        wp->w_status_height = oldwin->w_status_height;
+        wp->w_status_height = old_status_height;
         if (!(flags & WSP_BOT)) {
           oldwin->w_status_height = STATUS_HEIGHT;
         }
       }
     }
-    if ((flags & WSP_BOT) && !is_stl_global) {
-      frame_add_statusline(curfrp);
-    }
     frame_fix_height(wp);
     frame_fix_height(oldwin);
   }
@@ -1525,7 +1418,7 @@ int win_split_ins(int size, int flags, win_T *new_wp, int dir)
   // equalize the window sizes.
   if (do_equal || dir != 0) {
     win_equal(wp, true, (flags & WSP_VERT) ? (dir == 'v' ? 'b' : 'h') : (dir == 'h' ? 'b' : 'v'));
-  } else if (*p_spk != 'c' && !is_aucmd_win(wp)) {
+  } else if (!is_aucmd_win(wp)) {
     win_fix_scroll(false);
   }
 
@@ -1567,7 +1460,7 @@ int win_split_ins(int size, int flags, win_T *new_wp, int dir)
 // The windows will both edit the same buffer.
 // WSP_NEWLOC may be specified in flags to prevent the location list from
 // being copied.
-static void win_init(win_T *newp, win_T *oldp, int flags)
+void win_init(win_T *newp, win_T *oldp, int flags)
 {
   newp->w_buffer = oldp->w_buffer;
   newp->w_s = &(oldp->w_buffer->b_s);
@@ -1599,6 +1492,9 @@ static void win_init(win_T *newp, win_T *oldp, int flags)
                     ? NULL : xstrdup(oldp->w_prevdir);
 
   if (*p_spk != 'c') {
+    if (*p_spk == 't') {
+      newp->w_skipcol = oldp->w_skipcol;
+    }
     newp->w_botline = oldp->w_botline;
     newp->w_prev_height = oldp->w_height;
     newp->w_prev_winrow = oldp->w_winrow;
@@ -1641,24 +1537,6 @@ static void win_init_some(win_T *newp, win_T *oldp)
   win_copy_options(oldp, newp);
 }
 
-/// Return true if "win" is floating window in the current tab page.
-///
-/// @param  win  window to check
-bool win_valid_floating(const win_T *win)
-  FUNC_ATTR_PURE FUNC_ATTR_WARN_UNUSED_RESULT
-{
-  if (win == NULL) {
-    return false;
-  }
-
-  FOR_ALL_WINDOWS_IN_TAB(wp, curtab) {
-    if (wp == win) {
-      return wp->w_floating;
-    }
-  }
-  return false;
-}
-
 /// Check if "win" is a pointer to an existing window in the current tabpage.
 ///
 /// @param  win  window to check
@@ -1790,7 +1668,7 @@ int make_windows(int count, bool vertical)
 }
 
 // Exchange current and next window
-static void win_exchange(long Prenum)
+static void win_exchange(int Prenum)
 {
   if (curwin->w_floating) {
     emsg(e_floatexchange);
@@ -1802,6 +1680,10 @@ static void win_exchange(long Prenum)
     beep_flush();
     return;
   }
+  if (text_or_buf_locked()) {
+    beep_flush();
+    return;
+  }
 
   frame_T *frp;
 
@@ -1900,8 +1782,8 @@ static void win_rotate(bool upwards, int count)
     }
   }
 
-  win_T *wp1;
-  win_T *wp2;
+  win_T *wp1 = NULL;
+  win_T *wp2 = NULL;
 
   while (count--) {
     if (upwards) {              // first window becomes last window
@@ -2115,7 +1997,7 @@ void win_equal(win_T *next_curwin, bool current, int dir)
   win_equal_rec(next_curwin == NULL ? curwin : next_curwin, current,
                 topframe, dir, 0, tabline_height(),
                 Columns, topframe->fr_height);
-  if (*p_spk != 'c' && !is_aucmd_win(next_curwin)) {
+  if (!is_aucmd_win(next_curwin)) {
     win_fix_scroll(true);
   }
 }
@@ -2258,6 +2140,9 @@ static void win_equal_rec(win_T *next_curwin, bool current, frame_T *topfr, int
         }
         if (hnc) {                  // add next_curwin size
           next_curwin_size -= (int)p_wiw - (m - n);
+          if (next_curwin_size < 0) {
+            next_curwin_size = 0;
+          }
           new_size += next_curwin_size;
           room -= new_size - next_curwin_size;
         } else {
@@ -2407,7 +2292,7 @@ static void win_equal_rec(win_T *next_curwin, bool current, frame_T *topfr, int
   }
 }
 
-static void leaving_window(win_T *const win)
+void leaving_window(win_T *const win)
   FUNC_ATTR_NONNULL_ALL
 {
   // Only matters for a prompt window.
@@ -2585,6 +2470,23 @@ static bool can_close_floating_windows(void)
   return true;
 }
 
+/// @return true if, considering the cmdwin, `win` is safe to close.
+/// If false and `win` is the cmdwin, it is closed; otherwise, `err` is set.
+bool can_close_in_cmdwin(win_T *win, Error *err)
+  FUNC_ATTR_NONNULL_ALL
+{
+  if (cmdwin_type != 0) {
+    if (win == curwin) {
+      cmdwin_result = Ctrl_C;
+      return false;
+    } else if (win == cmdwin_old_curwin) {
+      api_set_error(err, kErrorTypeException, "%s", e_cmdwin);
+      return false;
+    }
+  }
+  return true;
+}
+
 /// Close the possibly last window in a tab page.
 ///
 /// @param  win          window to close
@@ -2599,6 +2501,7 @@ static bool close_last_window_tabpage(win_T *win, bool free_buf, tabpage_T *prev
   if (!ONE_WINDOW) {
     return false;
   }
+
   buf_T *old_curbuf = curbuf;
 
   Terminal *term = win->w_buffer ? win->w_buffer->terminal : NULL;
@@ -2636,10 +2539,11 @@ static bool close_last_window_tabpage(win_T *win, bool free_buf, tabpage_T *prev
   return true;
 }
 
-/// Close the buffer of "win" and unload it if "free_buf" is true.
+/// Close the buffer of "win" and unload it if "action" is DOBUF_UNLOAD.
+/// "action" can also be zero (do nothing).
 /// "abort_if_last" is passed to close_buffer(): abort closing if all other
 /// windows are closed.
-static void win_close_buffer(win_T *win, bool free_buf, bool abort_if_last)
+static void win_close_buffer(win_T *win, int action, bool abort_if_last)
 {
   // Free independent synblock before the buffer is freed.
   if (win->w_buffer != NULL) {
@@ -2658,7 +2562,7 @@ static void win_close_buffer(win_T *win, bool free_buf, bool abort_if_last)
     bufref_T bufref;
     set_bufref(&bufref, curbuf);
     win->w_closing = true;
-    close_buffer(win, win->w_buffer, free_buf ? DOBUF_UNLOAD : 0, abort_if_last, true);
+    close_buffer(win, win->w_buffer, action, abort_if_last, true);
     if (win_valid_any_tab(win)) {
       win->w_closing = false;
     }
@@ -2756,6 +2660,9 @@ int win_close(win_T *win, bool free_buf, bool force)
       reset_VIsual_and_resel();  // stop Visual mode
 
       other_buffer = true;
+      if (!win_valid(win)) {
+        return FAIL;
+      }
       win->w_closing = true;
       apply_autocmds(EVENT_BUFLEAVE, NULL, NULL, false, curbuf);
       if (!win_valid(win)) {
@@ -2788,7 +2695,7 @@ int win_close(win_T *win, bool free_buf, bool force)
     return OK;
   }
 
-  win_close_buffer(win, free_buf, true);
+  win_close_buffer(win, free_buf ? DOBUF_UNLOAD : 0, true);
 
   if (only_one_window() && win_valid(win) && win->w_buffer == NULL
       && (last_window(win) || curtab != prev_curtab
@@ -2872,7 +2779,7 @@ int win_close(win_T *win, bool free_buf, bool force)
     if (wp->w_p_pvw || bt_quickfix(wp->w_buffer)) {
       // If the cursor goes to the preview or the quickfix window, try
       // finding another window to go to.
-      for (;;) {
+      while (true) {
         if (wp->w_next == NULL) {
           wp = firstwin;
         } else {
@@ -2907,9 +2814,7 @@ int win_close(win_T *win, bool free_buf, bool force)
       win_equal(curwin, curwin->w_frame->fr_parent == win_frame, dir);
     } else {
       (void)win_comp_pos();
-      if (*p_spk != 'c') {
-        win_fix_scroll(false);
-      }
+      win_fix_scroll(false);
     }
   }
 
@@ -3326,20 +3231,20 @@ static frame_T *win_altframe(win_T *win, tabpage_T *tp)
   // By default the next window will get the space that was abandoned by this
   // window
   frame_T *target_fr = frp->fr_next;
-  frame_T *other_fr  = frp->fr_prev;
+  frame_T *other_fr = frp->fr_prev;
 
   // If this is part of a column of windows and 'splitbelow' is true then the
   // previous window will get the space.
   if (frp->fr_parent != NULL && frp->fr_parent->fr_layout == FR_COL && p_sb) {
     target_fr = frp->fr_prev;
-    other_fr  = frp->fr_next;
+    other_fr = frp->fr_next;
   }
 
   // If this is part of a row of windows, and 'splitright' is true then the
   // previous window will get the space.
   if (frp->fr_parent != NULL && frp->fr_parent->fr_layout == FR_ROW && p_spr) {
     target_fr = frp->fr_prev;
-    other_fr  = frp->fr_next;
+    other_fr = frp->fr_next;
   }
 
   // If 'wfh' or 'wfw' is set for the target and not for the alternate
@@ -3576,12 +3481,7 @@ static void frame_add_statusline(frame_T *frp)
 {
   if (frp->fr_layout == FR_LEAF) {
     win_T *wp = frp->fr_win;
-    if (wp->w_status_height == 0) {
-      if (wp->w_height - STATUS_HEIGHT >= 0) {           // don't make it negative
-        wp->w_height -= STATUS_HEIGHT;
-      }
-      wp->w_status_height = STATUS_HEIGHT;
-    }
+    wp->w_status_height = STATUS_HEIGHT;
   } else if (frp->fr_layout == FR_ROW) {
     // Handle all the frames in the row.
     FOR_ALL_FRAMES(frp, frp->fr_child) {
@@ -3728,12 +3628,7 @@ static void frame_add_hsep(const frame_T *frp)
 {
   if (frp->fr_layout == FR_LEAF) {
     win_T *wp = frp->fr_win;
-    if (wp->w_hsep_height == 0) {
-      if (wp->w_height > 0) {            // don't make it negative
-        wp->w_height++;
-      }
-      wp->w_hsep_height = 1;
-    }
+    wp->w_hsep_height = 1;
   } else if (frp->fr_layout == FR_ROW) {
     // Handle all the frames in the row.
     FOR_ALL_FRAMES(frp, frp->fr_child) {
@@ -3870,7 +3765,7 @@ void close_others(int message, int forceit)
   if (one_nonfloat() && !lastwin->w_floating) {
     if (message
         && !autocmd_busy) {
-      msg(_(m_onlyone));
+      msg(_(m_onlyone), 0);
     }
     return;
   }
@@ -3883,6 +3778,12 @@ void close_others(int message, int forceit)
       continue;
     }
 
+    // autoccommands messed this one up
+    if (!buf_valid(wp->w_buffer) && win_valid(wp)) {
+      wp->w_buffer = NULL;
+      win_close(wp, false, false);
+      continue;
+    }
     // Check if it's allowed to abandon this window
     int r = can_abandon(wp->w_buffer, forceit);
     if (!win_valid(wp)) {             // autocommands messed wp up
@@ -3968,7 +3869,7 @@ static int win_alloc_firstwin(win_T *oldwin)
   if (oldwin == NULL) {
     // Very first window, need to create an empty buffer for it and
     // initialize from scratch.
-    curbuf = buflist_new(NULL, NULL, 1L, BLN_LISTED);
+    curbuf = buflist_new(NULL, NULL, 1, BLN_LISTED);
     if (curbuf == NULL) {
       return FAIL;
     }
@@ -4024,7 +3925,7 @@ static tabpage_T *alloc_tabpage(void)
   static int last_tp_handle = 0;
   tabpage_T *tp = xcalloc(1, sizeof(tabpage_T));
   tp->handle = ++last_tp_handle;
-  pmap_put(handle_T)(&tabpage_handles, tp->handle, tp);
+  pmap_put(int)(&tabpage_handles, tp->handle, tp);
 
   // Init t: variables.
   tp->tp_vars = tv_dict_alloc();
@@ -4037,7 +3938,7 @@ static tabpage_T *alloc_tabpage(void)
 
 void free_tabpage(tabpage_T *tp)
 {
-  pmap_del(handle_T)(&tabpage_handles, tp->handle);
+  pmap_del(int)(&tabpage_handles, tp->handle, NULL);
   diff_clear(tp);
   for (int idx = 0; idx < SNAP_COUNT; idx++) {
     clear_snapshot(tp, idx);
@@ -4081,7 +3982,7 @@ int win_new_tabpage(int after, char *filename)
   }
 
   newtp->tp_localdir = old_curtab->tp_localdir
-    ? xstrdup(old_curtab->tp_localdir) : NULL;
+                       ? xstrdup(old_curtab->tp_localdir) : NULL;
 
   curtab = newtp;
 
@@ -4144,12 +4045,17 @@ int may_open_tabpage(void)
 {
   int n = (cmdmod.cmod_tab == 0) ? postponed_split_tab : cmdmod.cmod_tab;
 
-  if (n != 0) {
-    cmdmod.cmod_tab = 0;         // reset it to avoid doing it twice
-    postponed_split_tab = 0;
-    return win_new_tabpage(n, NULL);
+  if (n == 0) {
+    return FAIL;
+  }
+
+  cmdmod.cmod_tab = 0;         // reset it to avoid doing it twice
+  postponed_split_tab = 0;
+  int status = win_new_tabpage(n, NULL);
+  if (status == OK) {
+    apply_autocmds(EVENT_TABNEWENTERED, NULL, NULL, false, curbuf);
   }
-  return FAIL;
+  return status;
 }
 
 // Create up to "maxcount" tabpages with empty windows.
@@ -4494,11 +4400,12 @@ void goto_tabpage_tp(tabpage_T *tp, bool trigger_enter_autocmds, bool trigger_le
 /// @return true if the tab page is valid, false otherwise.
 bool goto_tabpage_lastused(void)
 {
-  if (valid_tabpage(lastused_tabpage)) {
-    goto_tabpage_tp(lastused_tabpage, true, true);
-    return true;
+  if (!valid_tabpage(lastused_tabpage)) {
+    return false;
   }
-  return false;
+
+  goto_tabpage_tp(lastused_tabpage, true, true);
+  return true;
 }
 
 // Enter window "wp" in tab page "tp".
@@ -4615,7 +4522,7 @@ tabpage_T *win_find_tabpage(win_T *win)
 /// @param count  nth neighbor window
 ///
 /// @return       found window
-win_T *win_vert_neighbor(tabpage_T *tp, win_T *wp, bool up, long count)
+win_T *win_vert_neighbor(tabpage_T *tp, win_T *wp, bool up, int count)
 {
   frame_T *foundfr = wp->w_frame;
 
@@ -4628,7 +4535,7 @@ win_T *win_vert_neighbor(tabpage_T *tp, win_T *wp, bool up, long count)
     // First go upwards in the tree of frames until we find an upwards or
     // downwards neighbor.
     frame_T *fr = foundfr;
-    for (;;) {
+    while (true) {
       if (fr == tp->tp_topframe) {
         goto end;
       }
@@ -4644,7 +4551,7 @@ win_T *win_vert_neighbor(tabpage_T *tp, win_T *wp, bool up, long count)
     }
 
     // Now go downwards to find the bottom or top frame in it.
-    for (;;) {
+    while (true) {
       if (nfr->fr_layout == FR_LEAF) {
         foundfr = nfr;
         break;
@@ -4674,7 +4581,7 @@ end:
 ///
 /// @param up     true to go to win above
 /// @param count  go count times into direction
-static void win_goto_ver(bool up, long count)
+static void win_goto_ver(bool up, int count)
 {
   win_T *win = win_vert_neighbor(curtab, curwin, up, count);
   if (win != NULL) {
@@ -4691,7 +4598,7 @@ static void win_goto_ver(bool up, long count)
 /// @param count nth neighbor window
 ///
 /// @return      found window
-win_T *win_horz_neighbor(tabpage_T *tp, win_T *wp, bool left, long count)
+win_T *win_horz_neighbor(tabpage_T *tp, win_T *wp, bool left, int count)
 {
   frame_T *foundfr = wp->w_frame;
 
@@ -4704,7 +4611,7 @@ win_T *win_horz_neighbor(tabpage_T *tp, win_T *wp, bool left, long count)
     // First go upwards in the tree of frames until we find a left or
     // right neighbor.
     frame_T *fr = foundfr;
-    for (;;) {
+    while (true) {
       if (fr == tp->tp_topframe) {
         goto end;
       }
@@ -4720,7 +4627,7 @@ win_T *win_horz_neighbor(tabpage_T *tp, win_T *wp, bool left, long count)
     }
 
     // Now go downwards to find the leftmost or rightmost frame in it.
-    for (;;) {
+    while (true) {
       if (nfr->fr_layout == FR_LEAF) {
         foundfr = nfr;
         break;
@@ -4750,7 +4657,7 @@ end:
 ///
 /// @param left   true to go to left window
 /// @param count  go count times into direction
-static void win_goto_hor(bool left, long count)
+static void win_goto_hor(bool left, int count)
 {
   win_T *win = win_horz_neighbor(curtab, curwin, left, count);
   if (win != NULL) {
@@ -4811,7 +4718,7 @@ static void win_enter_ext(win_T *const wp, const int flags)
 
   // Might need to scroll the old window before switching, e.g., when the
   // cursor was moved.
-  if (*p_spk == 'c') {
+  if (*p_spk == 'c' && !curwin_invalid) {
     update_topline(curwin);
   }
 
@@ -4833,7 +4740,9 @@ static void win_enter_ext(win_T *const wp, const int flags)
   if (*p_spk == 'c') {
     changed_line_abv_curs();      // assume cursor position needs updating
   } else {
-    win_fix_cursor(true);
+    // Make sure the cursor position is valid, either by moving the cursor
+    // or by scrolling the text.
+    win_fix_cursor(get_real_state() & (MODE_NORMAL|MODE_CMDLINE|MODE_TERMINAL));
   }
 
   fix_current_dir();
@@ -4848,8 +4757,6 @@ static void win_enter_ext(win_T *const wp, const int flags)
     if (other_buffer) {
       apply_autocmds(EVENT_BUFENTER, NULL, NULL, false, curbuf);
     }
-    apply_autocmds(EVENT_CURSORMOVED, NULL, NULL, false, curbuf);
-    curwin->w_last_cursormoved = curwin->w_cursor;
   }
 
   maketitle();
@@ -4997,7 +4904,7 @@ win_T *buf_jump_open_tab(buf_T *buf)
 
 /// @param hidden  allocate a window structure and link it in the window if
 //                 false.
-static win_T *win_alloc(win_T *after, bool hidden)
+win_T *win_alloc(win_T *after, bool hidden)
 {
   static int last_win_id = LOWEST_WIN_ID - 1;
 
@@ -5005,7 +4912,7 @@ static win_T *win_alloc(win_T *after, bool hidden)
   win_T *new_wp = xcalloc(1, sizeof(win_T));
 
   new_wp->handle = ++last_win_id;
-  pmap_put(handle_T)(&window_handles, new_wp->handle, new_wp);
+  pmap_put(int)(&window_handles, new_wp->handle, new_wp);
 
   grid_assign_handle(&new_wp->w_grid_alloc);
 
@@ -5034,12 +4941,13 @@ static win_T *win_alloc(win_T *after, bool hidden)
   new_wp->w_floating = 0;
   new_wp->w_float_config = FLOAT_CONFIG_INIT;
   new_wp->w_viewport_invalid = true;
+  new_wp->w_viewport_last_topline = 1;
 
   new_wp->w_ns_hl = -1;
 
   // use global option for global-local options
-  new_wp->w_p_so = -1;
-  new_wp->w_p_siso = -1;
+  new_wp->w_allbuf_opt.wo_so = new_wp->w_p_so = -1;
+  new_wp->w_allbuf_opt.wo_siso = new_wp->w_p_siso = -1;
 
   // We won't calculate w_fraction until resizing the window
   new_wp->w_fraction = 0;
@@ -5066,14 +4974,13 @@ void free_wininfo(wininfo_T *wip, buf_T *bp)
 /// @param tp  tab page "win" is in, NULL for current
 static void win_free(win_T *wp, tabpage_T *tp)
 {
-  pmap_del(handle_T)(&window_handles, wp->handle);
+  pmap_del(int)(&window_handles, wp->handle, NULL);
   clearFolding(wp);
 
   // reduce the reference count to the argument list.
   alist_unlink(wp->w_alist);
 
   // Don't execute autocommands while the window is halfway being deleted.
-  // gui_mch_destroy_scrollbar() may trigger a FocusGained event.
   block_autocmds();
 
   clear_winopt(&wp->w_onebuf_opt);
@@ -5145,8 +5052,9 @@ static void win_free(win_T *wp, tabpage_T *tp)
     }
   }
 
-  // free the border title text
+  // free the border text
   clear_virttext(&wp->w_float_config.title_chunks);
+  clear_virttext(&wp->w_float_config.footer_chunks);
 
   clear_matches(wp);
 
@@ -5263,8 +5171,8 @@ static void frame_remove(frame_T *frp)
 
 void win_new_screensize(void)
 {
-  static long old_Rows = 0;
-  static long old_Columns = 0;
+  static int old_Rows = 0;
+  static int old_Columns = 0;
 
   if (old_Rows != Rows) {
     // If 'window' uses the whole screen, keep it using that.
@@ -5306,7 +5214,7 @@ void win_new_screen_rows(void)
   compute_cmdrow();
   curtab->tp_ch_used = p_ch;
 
-  if (*p_spk != 'c' && !skip_win_fix_scroll) {
+  if (!skip_win_fix_scroll) {
     win_fix_scroll(true);
   }
 }
@@ -5364,7 +5272,7 @@ static dict_T *make_win_info_dict(int width, int height, int topline, int topfil
   d->dv_refcount = 1;
 
   // not actually looping, for breaking out on error
-  while (1) {
+  while (true) {
     typval_T tv = {
       .v_lock = VAR_UNLOCKED,
       .v_type = VAR_NUMBER,
@@ -5617,8 +5525,9 @@ void win_size_save(garray_T *gap)
 {
   ga_init(gap, (int)sizeof(int), 1);
   ga_grow(gap, win_count() * 2 + 1);
-  // first entry is value of 'lines'
-  ((int *)gap->ga_data)[gap->ga_len++] = Rows;
+  // first entry is the total lines available for windows
+  ((int *)gap->ga_data)[gap->ga_len++] =
+    (int)ROWS_AVAIL + global_stl_height() - last_stl_height(false);
 
   FOR_ALL_WINDOWS_IN_TAB(wp, curtab) {
     ((int *)gap->ga_data)[gap->ga_len++] =
@@ -5628,13 +5537,14 @@ void win_size_save(garray_T *gap)
 }
 
 // Restore window sizes, but only if the number of windows is still the same
-// and 'lines' didn't change.
+// and total lines available for windows didn't change.
 // Does not free the growarray.
 void win_size_restore(garray_T *gap)
   FUNC_ATTR_NONNULL_ALL
 {
   if (win_count() * 2 + 1 == gap->ga_len
-      && ((int *)gap->ga_data)[0] == Rows) {
+      && ((int *)gap->ga_data)[0] ==
+      ROWS_AVAIL + global_stl_height() - last_stl_height(false)) {
     // The order matters, because frames contain other frames, but it's
     // difficult to get right. The easy way out is to do it twice.
     for (int j = 0; j < 2; j++) {
@@ -5672,13 +5582,6 @@ int win_comp_pos(void)
   return row + global_stl_height();
 }
 
-void win_reconfig_floats(void)
-{
-  for (win_T *wp = lastwin; wp && wp->w_floating; wp = wp->w_prev) {
-    win_config_float(wp, wp->w_float_config);
-  }
-}
-
 // Update the position of the windows in frame "topfrp", using the width and
 // height of the frames.
 // "*row" and "*col" are the top-left position of the frame.  They are updated
@@ -5753,9 +5656,7 @@ void win_setheight_win(int height, win_T *win)
     msg_row = row;
     msg_col = 0;
 
-    if (*p_spk != 'c') {
-      win_fix_scroll(true);
-    }
+    win_fix_scroll(true);
 
     redraw_all_later(UPD_NOT_VALID);
     redraw_cmdline = true;
@@ -6079,7 +5980,7 @@ static void frame_setwidth(frame_T *curfrp, int width)
 }
 
 // Check 'winminheight' for a valid value and reduce it if needed.
-void win_setminheight(void)
+const char *did_set_winminheight(optset_T *args FUNC_ATTR_UNUSED)
 {
   bool first = true;
 
@@ -6096,10 +5997,11 @@ void win_setminheight(void)
       first = false;
     }
   }
+  return NULL;
 }
 
 // Check 'winminwidth' for a valid value and reduce it if needed.
-void win_setminwidth(void)
+const char *did_set_winminwidth(optset_T *args FUNC_ATTR_UNUSED)
 {
   bool first = true;
 
@@ -6116,6 +6018,7 @@ void win_setminwidth(void)
       first = false;
     }
   }
+  return NULL;
 }
 
 /// Status line of dragwin is dragged "offset" lines down (negative is up).
@@ -6233,9 +6136,7 @@ void win_drag_status_line(win_T *dragwin, int offset)
   p_ch = MAX(Rows - cmdline_row, p_ch_was_zero ? 0 : 1);
   curtab->tp_ch_used = p_ch;
 
-  if (*p_spk != 'c') {
-    win_fix_scroll(true);
-  }
+  win_fix_scroll(true);
 
   redraw_all_later(UPD_SOME_VALID);
   showmode();
@@ -6340,7 +6241,7 @@ void win_drag_vsep_line(win_T *dragwin, int offset)
   redraw_all_later(UPD_NOT_VALID);
 }
 
-#define FRACTION_MULT   16384L
+#define FRACTION_MULT   16384
 
 // Set wp->w_fraction for the current w_wrow and w_height.
 // Has no effect when the window is less than two lines.
@@ -6350,45 +6251,56 @@ void set_fraction(win_T *wp)
     // When cursor is in the first line the percentage is computed as if
     // it's halfway that line.  Thus with two lines it is 25%, with three
     // lines 17%, etc.  Similarly for the last line: 75%, 83%, etc.
-    wp->w_fraction = (int)(wp->w_wrow * FRACTION_MULT + FRACTION_MULT / 2) / wp->w_height_inner;
+    wp->w_fraction = (wp->w_wrow * FRACTION_MULT + FRACTION_MULT / 2) / wp->w_height_inner;
   }
 }
 
-/// Handle scroll position for 'splitkeep'.  Replaces scroll_to_fraction()
-/// call from win_set_inner_size().  Instead we iterate over all windows in a
-/// tabpage and calculate the new scroll position.
-/// TODO(luukvbaal): Ensure this also works with wrapped lines.
-/// Requires topline to be able to be set to a bufferline with some
-/// offset(row-wise scrolling/smoothscroll).
+/// Handle scroll position, depending on 'splitkeep'.  Replaces the
+/// scroll_to_fraction() call from win_new_height() if 'splitkeep' is "screen"
+/// or "topline".  Instead we iterate over all windows in a tabpage and
+/// calculate the new scroll position.
+/// TODO(vim): Ensure this also works with wrapped lines.
+/// Requires a not fully visible cursor line to be allowed at the bottom of
+/// a window("zb"), probably only when 'smoothscroll' is also set.
 void win_fix_scroll(int resize)
 {
-  linenr_T lnum;
+  if (*p_spk == 'c') {
+    return;  // 'splitkeep' is "cursor"
+  }
 
   skip_update_topline = true;
   FOR_ALL_WINDOWS_IN_TAB(wp, curtab) {
     // Skip when window height has not changed or when floating.
     if (!wp->w_floating && wp->w_height != wp->w_prev_height) {
+      // Cursor position in this window may now be invalid.  It is kept
+      // potentially invalid until the window is made the current window.
+      wp->w_do_win_fix_cursor = true;
+
       // If window has moved update botline to keep the same screenlines.
       if (*p_spk == 's' && wp->w_winrow != wp->w_prev_winrow
           && wp->w_botline - 1 <= wp->w_buffer->b_ml.ml_line_count) {
-        lnum = wp->w_cursor.lnum;
         int diff = (wp->w_winrow - wp->w_prev_winrow)
                    + (wp->w_height - wp->w_prev_height);
+        linenr_T lnum = wp->w_cursor.lnum;
         wp->w_cursor.lnum = wp->w_botline - 1;
+
         // Add difference in height and row to botline.
         if (diff > 0) {
           cursor_down_inner(wp, diff);
         } else {
           cursor_up_inner(wp, -diff);
         }
-        // Bring the new cursor position to the bottom of the screen.
+
+        // Scroll to put the new cursor position at the bottom of the
+        // screen.
         wp->w_fraction = FRACTION_MULT;
         scroll_to_fraction(wp, wp->w_prev_height);
         wp->w_cursor.lnum = lnum;
       } else if (wp == curwin) {
         wp->w_valid &= ~VALID_CROW;
       }
-      invalidate_botline_win(wp);
+
+      invalidate_botline(wp);
       validate_botline(wp);
     }
     wp->w_prev_height = wp->w_height;
@@ -6405,40 +6317,45 @@ void win_fix_scroll(int resize)
 
 /// Make sure the cursor position is valid for 'splitkeep'.
 /// If it is not, put the cursor position in the jumplist and move it.
-/// If we are not in normal mode, scroll to make valid instead.
-static void win_fix_cursor(int normal)
+/// If we are not in normal mode ("normal" is false), make it valid by scrolling
+/// instead.
+static void win_fix_cursor(bool normal)
 {
   win_T *wp = curwin;
-  long so = get_scrolloff_value(wp);
-  linenr_T nlnum = 0;
-  linenr_T lnum = wp->w_cursor.lnum;
 
-  if (wp->w_buffer->b_ml.ml_line_count < wp->w_height
-      || skip_win_fix_cursor) {
+  if (skip_win_fix_cursor
+      || !wp->w_do_win_fix_cursor
+      || wp->w_buffer->b_ml.ml_line_count < wp->w_height_inner) {
     return;
   }
 
+  wp->w_do_win_fix_cursor = false;
   // Determine valid cursor range.
-  so = MIN(wp->w_height_inner / 2, so);
+  int so = MIN(wp->w_height_inner / 2, get_scrolloff_value(wp));
+  linenr_T lnum = wp->w_cursor.lnum;
+
   wp->w_cursor.lnum = wp->w_topline;
-  linenr_T top = cursor_down_inner(wp, so);
+  cursor_down_inner(wp, so);
+  linenr_T top = wp->w_cursor.lnum;
+
   wp->w_cursor.lnum = wp->w_botline - 1;
-  linenr_T bot = cursor_up_inner(wp, so);
+  cursor_up_inner(wp, so);
+  linenr_T bot = wp->w_cursor.lnum;
+
   wp->w_cursor.lnum = lnum;
   // Check if cursor position is above or below valid cursor range.
+  linenr_T nlnum = 0;
   if (lnum > bot && (wp->w_botline - wp->w_buffer->b_ml.ml_line_count) != 1) {
     nlnum = bot;
   } else if (lnum < top && wp->w_topline != 1) {
-    nlnum = (so == wp->w_height / 2) ? bot : top;
+    nlnum = (so == wp->w_height_inner / 2) ? bot : top;
   }
 
-  if (nlnum) {  // Cursor is invalid for current scroll position.
-    if (normal) {
-      // Save to jumplist and set cursor to avoid scrolling.
+  if (nlnum != 0) {  // Cursor is invalid for current scroll position.
+    if (normal) {    // Save to jumplist and set cursor to avoid scrolling.
       setmark('\'');
       wp->w_cursor.lnum = nlnum;
-    } else {
-      // Scroll instead when not in normal mode.
+    } else {         // Scroll instead when not in normal mode.
       wp->w_fraction = (nlnum == bot) ? FRACTION_MULT : 0;
       scroll_to_fraction(wp, wp->w_prev_height);
       validate_botline(curwin);
@@ -6485,8 +6402,8 @@ void scroll_to_fraction(win_T *wp, int prev_height)
     if (lnum < 1) {             // can happen when starting up
       lnum = 1;
     }
-    wp->w_wrow = (int)((long)wp->w_fraction * (long)height - 1L) / FRACTION_MULT;
-    int line_size = plines_win_col(wp, lnum, (long)(wp->w_cursor.col)) - 1;
+    wp->w_wrow = (wp->w_fraction * height - 1) / FRACTION_MULT;
+    int line_size = plines_win_col(wp, lnum, wp->w_cursor.col) - 1;
     int sline = wp->w_wrow - line_size;
 
     if (sline >= 0) {
@@ -6549,9 +6466,6 @@ void scroll_to_fraction(win_T *wp, int prev_height)
   }
 
   if (wp == curwin) {
-    if (get_scrolloff_value(wp)) {
-      update_topline(wp);
-    }
     curs_columns(wp, false);        // validate w_wrow
   }
   if (prev_height > 0) {
@@ -6559,7 +6473,7 @@ void scroll_to_fraction(win_T *wp, int prev_height)
   }
 
   redraw_later(wp, UPD_SOME_VALID);
-  invalidate_botline_win(wp);
+  invalidate_botline(wp);
 }
 
 void win_set_inner_size(win_T *wp, bool valid_cursor)
@@ -6582,20 +6496,20 @@ void win_set_inner_size(win_T *wp, bool valid_cursor)
         // call win_new_height() recursively.
         validate_cursor();
       }
-      if (wp->w_height_inner != prev_height) {  // -V547
+      if (wp->w_height_inner != prev_height) {
         return;  // Recursive call already changed the size, bail out.
       }
       if (wp->w_wrow != wp->w_prev_fraction_row) {
         set_fraction(wp);
       }
     }
-    wp->w_skipcol = 0;
     wp->w_height_inner = height;
     win_comp_scroll(wp);
 
     // There is no point in adjusting the scroll position when exiting.  Some
     // values might be invalid.
     if (valid_cursor && !exiting && *p_spk == 'c') {
+      wp->w_skipcol = 0;
       scroll_to_fraction(wp, prev_height);
     }
     redraw_later(wp, UPD_SOME_VALID);
@@ -6606,12 +6520,9 @@ void win_set_inner_size(win_T *wp, bool valid_cursor)
     wp->w_lines_valid = 0;
     if (valid_cursor) {
       changed_line_abv_curs_win(wp);
-      invalidate_botline_win(wp);
-      if (wp == curwin) {
-        skip_update_topline = (*p_spk != 'c');
-        update_topline(wp);
+      invalidate_botline(wp);
+      if (wp == curwin && *p_spk == 'c') {
         curs_columns(wp, true);  // validate w_wrow
-        skip_update_topline = false;
       }
     }
     redraw_later(wp, UPD_NOT_VALID);
@@ -6628,27 +6539,18 @@ void win_set_inner_size(win_T *wp, bool valid_cursor)
   wp->w_redr_status = true;
 }
 
-static int win_border_height(win_T *wp)
-{
-  return wp->w_border_adj[0] + wp->w_border_adj[2];
-}
-
-static int win_border_width(win_T *wp)
-{
-  return wp->w_border_adj[1] + wp->w_border_adj[3];
-}
-
 /// Set the width of a window.
 void win_new_width(win_T *wp, int width)
 {
-  wp->w_width = width;
+  // Should we give an error if width < 0?
+  wp->w_width = width < 0 ? 0 : width;
   wp->w_pos_changed = true;
   win_set_inner_size(wp, true);
 }
 
 void win_comp_scroll(win_T *wp)
 {
-  const long old_w_p_scr = wp->w_p_scr;
+  const OptInt old_w_p_scr = wp->w_p_scr;
 
   wp->w_p_scr = wp->w_height_inner / 2;
   if (wp->w_p_scr == 0) {
@@ -6744,7 +6646,7 @@ void command_height(void)
 static void frame_add_height(frame_T *frp, int n)
 {
   frame_new_height(frp, frp->fr_height + n, false, false);
-  for (;;) {
+  while (true) {
     frp = frp->fr_parent;
     if (frp == NULL) {
       break;
@@ -6756,7 +6658,7 @@ static void frame_add_height(frame_T *frp, int n)
 // Get the file name at the cursor.
 // If Visual mode is active, use the selected text if it's in one line.
 // Returns the name in allocated memory, NULL for failure.
-char *grab_file_name(long count, linenr_T *file_lnum)
+char *grab_file_name(int count, linenr_T *file_lnum)
 {
   int options = FNAME_MESS | FNAME_EXP | FNAME_REL | FNAME_UNESC;
   if (VIsual_active) {
@@ -6769,7 +6671,7 @@ char *grab_file_name(long count, linenr_T *file_lnum)
     if (file_lnum != NULL && ptr[len] == ':' && isdigit((uint8_t)ptr[len + 1])) {
       char *p = ptr + len + 1;
 
-      *file_lnum = (linenr_T)getdigits_long(&p, false, 0);
+      *file_lnum = getdigits_int32(&p, false, 0);
     }
     return find_file_name_in_path(ptr, len, options, count, curbuf->b_ffname);
   }
@@ -6787,7 +6689,7 @@ char *grab_file_name(long count, linenr_T *file_lnum)
 // FNAME_EXP        expand to path
 // FNAME_HYP        check for hypertext link
 // FNAME_INCL       apply "includeexpr"
-char *file_name_at_cursor(int options, long count, linenr_T *file_lnum)
+char *file_name_at_cursor(int options, int count, linenr_T *file_lnum)
 {
   return file_name_in_line(get_cursor_line_ptr(),
                            curwin->w_cursor.col, options, count, curbuf->b_ffname,
@@ -6798,7 +6700,7 @@ char *file_name_at_cursor(int options, long count, linenr_T *file_lnum)
 /// @param file_lnum  line number after the file name
 ///
 /// @return  the name of the file under or after ptr[col]. Otherwise like file_name_at_cursor().
-char *file_name_in_line(char *line, int col, int options, long count, char *rel_fname,
+char *file_name_in_line(char *line, int col, int options, int count, char *rel_fname,
                         linenr_T *file_lnum)
 {
   // search forward for what could be the start of a file name
@@ -6818,12 +6720,12 @@ char *file_name_in_line(char *line, int col, int options, long count, char *rel_
   bool is_url = false;
 
   // Search backward for first char of the file name.
-  // Go one char back to ":" before "//" even when ':' is not in 'isfname'.
+  // Go one char back to ":" before "//", or to the drive letter before ":\" (even if ":"
+  // is not in 'isfname').
   while (ptr > line) {
     if ((len = (size_t)(utf_head_off(line, ptr - 1))) > 0) {
       ptr -= len + 1;
-    } else if (vim_isfilec((uint8_t)ptr[-1])
-               || ((options & FNAME_HYP) && path_is_url(ptr - 1))) {
+    } else if (vim_isfilec((uint8_t)ptr[-1]) || ((options & FNAME_HYP) && path_is_url(ptr - 1))) {
       ptr--;
     } else {
       break;
@@ -6832,14 +6734,13 @@ char *file_name_in_line(char *line, int col, int options, long count, char *rel_
 
   // Search forward for the last char of the file name.
   // Also allow ":/" when ':' is not in 'isfname'.
-  len = 0;
+  len = path_has_drive_letter(ptr) ? 2 : 0;
   while (vim_isfilec((uint8_t)ptr[len]) || (ptr[len] == '\\' && ptr[len + 1] == ' ')
          || ((options & FNAME_HYP) && path_is_url(ptr + len))
          || (is_url && vim_strchr(":?&=", (uint8_t)ptr[len]) != NULL)) {
     // After type:// we also include :, ?, & and = as valid characters, so that
     // http://google.com:8080?q=this&that=ok works.
-    if ((ptr[len] >= 'A' && ptr[len] <= 'Z')
-        || (ptr[len] >= 'a' && ptr[len] <= 'z')) {
+    if ((ptr[len] >= 'A' && ptr[len] <= 'Z') || (ptr[len] >= 'a' && ptr[len] <= 'z')) {
       if (in_type && path_is_url(ptr + len + 1)) {
         is_url = true;
       }
@@ -6897,8 +6798,7 @@ char *file_name_in_line(char *line, int col, int options, long count, char *rel_
 void last_status(bool morewin)
 {
   // Don't make a difference between horizontal or vertical split.
-  last_status_rec(topframe, (p_ls == 2 || (p_ls == 1 && (morewin || !one_nonfloat()))),
-                  global_stl_height() > 0);
+  last_status_rec(topframe, last_stl_height(morewin) > 0, global_stl_height() > 0);
 }
 
 // Remove status line from window, replacing it with a horizontal separator if needed.
@@ -7097,6 +6997,14 @@ int global_stl_height(void)
   return (p_ls == 3) ? STATUS_HEIGHT : 0;
 }
 
+/// Return the height of the last window's statusline, or the global statusline if set.
+///
+/// @param morewin  pretend there are two or more windows if true.
+int last_stl_height(bool morewin)
+{
+  return (p_ls > 1 || (p_ls == 1 && (morewin || !one_nonfloat()))) ? STATUS_HEIGHT : 0;
+}
+
 /// Return the minimal number of rows that is needed on the screen to display
 /// the current number of windows.
 int min_rows(void)
@@ -7193,8 +7101,9 @@ void reset_lnums(void)
 {
   FOR_ALL_TAB_WINDOWS(tp, wp) {
     if (wp->w_buffer == curbuf) {
-      // Restore the value if the autocommand didn't change it and it was
-      // set.
+      // Restore the value if the autocommand didn't change it and it was set.
+      // Note: This triggers e.g. on BufReadPre, when the buffer is not yet
+      //       loaded, so cannot validate the buffer line
       if (equalpos(wp->w_save_cursor.w_cursor_corr, wp->w_cursor)
           && wp->w_save_cursor.w_cursor_save.lnum != 0) {
         wp->w_cursor = wp->w_save_cursor.w_cursor_save;
@@ -7203,6 +7112,9 @@ void reset_lnums(void)
           && wp->w_save_cursor.w_topline_save != 0) {
         wp->w_topline = wp->w_save_cursor.w_topline_save;
       }
+      if (wp->w_save_cursor.w_topline_save > wp->w_buffer->b_ml.ml_line_count) {
+        wp->w_valid &= ~VALID_TOPLINE;
+      }
     }
   }
 }
@@ -7250,11 +7162,12 @@ static void clear_snapshot(tabpage_T *tp, int idx)
 
 static void clear_snapshot_rec(frame_T *fr)
 {
-  if (fr != NULL) {
-    clear_snapshot_rec(fr->fr_next);
-    clear_snapshot_rec(fr->fr_child);
-    xfree(fr);
+  if (fr == NULL) {
+    return;
   }
+  clear_snapshot_rec(fr->fr_next);
+  clear_snapshot_rec(fr->fr_child);
+  xfree(fr);
 }
 
 /// Traverse a snapshot to find the previous curwin.
@@ -7404,13 +7317,13 @@ static int int_cmp(const void *a, const void *b)
 /// Handle setting 'colorcolumn' or 'textwidth' in window "wp".
 ///
 /// @return error message, NULL if it's OK.
-char *check_colorcolumn(win_T *wp)
+const char *check_colorcolumn(win_T *wp)
 {
   if (wp->w_buffer == NULL) {
     return NULL;      // buffer was closed
   }
 
-  unsigned int count = 0;
+  unsigned count = 0;
   int color_cols[256];
   for (char *s = wp->w_p_cc; *s != NUL && count < 255;) {
     int col;
@@ -7463,7 +7376,7 @@ skip:
     qsort(color_cols, count, sizeof(int), int_cmp);
 
     int j = 0;
-    for (unsigned int i = 0; i < count; i++) {
+    for (unsigned i = 0; i < count; i++) {
       // skip duplicates
       if (j == 0 || wp->w_p_cc_cols[j - 1] != color_cols[i]) {
         wp->w_p_cc_cols[j++] = color_cols[i];