Merge #6816 'TUI improvements'

Removed these commits (test-suite changes):
e2fba01910
7c809c4bc7
18e7cd9e97

src/nvim/option.c

@@ -969,10 +969,13 @@ void set_init_2(bool headless)
     p_window = Rows - 1;
   }
   set_number_default("window", Rows - 1);
+#if 0
+  // This bodges around problems that should be fixed in the TUI layer.
   if (!headless && !os_term_is_nice()) {
     set_string_option_direct((char_u *)"guicursor", -1, (char_u *)"",
                              OPT_GLOBAL, SID_NONE);
   }
+#endif
   parse_shape_opt(SHAPE_CURSOR);   // set cursor shapes from 'guicursor'
   (void)parse_printoptions();      // parse 'printoptions' default value
 }

src/nvim/screen.c

@@ -4230,7 +4230,6 @@ win_line (
          * (regardless of the xn,am settings).
          * Only do this if the cursor is on the current line
          * (something has been written in it).
-         * Don't do this for the GUI.
          * Don't do this for double-width characters.
          * Don't do this for a window not at the right screen border.
          */
@@ -5846,12 +5845,12 @@ static void screen_char(unsigned off, int row, int col)
   if (row >= screen_Rows || col >= screen_Columns)
     return;
 
-  /* Outputting the last character on the screen may scrollup the screen.
-   * Don't to it!  Mark the character invalid (update it when scrolled up) */
+  // Outputting the last character on the screen may scrollup the screen.
+  // Don't to it!  Mark the character invalid (update it when scrolled up)
+  // FIXME: The premise here is not actually true (cf. deferred wrap).
   if (row == screen_Rows - 1 && col == screen_Columns - 1
-      /* account for first command-line character in rightleft mode */
-      && !cmdmsg_rl
-      ) {
+      // account for first command-line character in rightleft mode
+      && !cmdmsg_rl) {
     ScreenAttrs[off] = (sattr_T)-1;
     return;
   }

src/nvim/tui/terminfo.h

@@ -0,0 +1,10 @@
+#ifndef NVIM_TUI_TERMINFO_H
+#define NVIM_TUI_TERMINFO_H
+
+#include <unibilium.h>
+
+#ifdef INCLUDE_GENERATED_DECLARATIONS
+# include "tui/terminfo.h.generated.h"
+#endif
+
+#endif  // NVIM_TUI_TERMINFO_H