Merge pull request #19953 from zeertzjq/vim-9.0.0036

vim-patch:8.2.2524,9.0.(0036,0037,0038,0040}

12 files changed, 179 insertions, 97 deletions

diff --git a/src/nvim/buffer_defs.h b/src/nvim/buffer_defs.h
index d7d680b0fd..c0d7f8d066 100644
--- a/src/nvim/buffer_defs.h
+++ b/src/nvim/buffer_defs.h
@@ -257,10 +257,10 @@ typedef struct {
 #define w_p_scl w_onebuf_opt.wo_scl    // 'signcolumn'
   char *wo_winhl;
 #define w_p_winhl w_onebuf_opt.wo_winhl    // 'winhighlight'
-  char *wo_fcs;
-#define w_p_fcs w_onebuf_opt.wo_fcs    // 'fillchars'
   char *wo_lcs;
 #define w_p_lcs w_onebuf_opt.wo_lcs    // 'listchars'
+  char *wo_fcs;
+#define w_p_fcs w_onebuf_opt.wo_fcs    // 'fillchars'
   long wo_winbl;
 #define w_p_winbl w_onebuf_opt.wo_winbl  // 'winblend'
 
diff --git a/src/nvim/charset.c b/src/nvim/charset.c
index ff58810ff0..d48cadf356 100644
--- a/src/nvim/charset.c
+++ b/src/nvim/charset.c
@@ -1655,7 +1655,7 @@ int hex2nr(int c)
 
 /// Convert two hex characters to a byte.
 /// Return -1 if one of the characters is not hex.
-int hexhex2nr(char_u *p)
+int hexhex2nr(const char_u *p)
   FUNC_ATTR_PURE
 {
   if (!ascii_isxdigit(p[0]) || !ascii_isxdigit(p[1])) {
diff --git a/src/nvim/drawline.c b/src/nvim/drawline.c
index f1a808e2bc..22b0f26a1c 100644
--- a/src/nvim/drawline.c
+++ b/src/nvim/drawline.c
@@ -1247,7 +1247,7 @@ int win_line(win_T *wp, linenr_T lnum, int startrow, int endrow, bool nochange,
           }
           char_attr = 0;
         } else if (filler_todo > 0) {
-          // draw "deleted" diff line(s)
+          // Draw "deleted" diff line(s)
           if (char2cells(wp->w_p_fcs_chars.diff) > 1) {
             c_extra = '-';
             c_final = NUL;
diff --git a/src/nvim/drawscreen.c b/src/nvim/drawscreen.c
index 012c4ecb19..cf8178a30f 100644
--- a/src/nvim/drawscreen.c
+++ b/src/nvim/drawscreen.c
@@ -1920,8 +1920,9 @@ win_update_start:
       wp->w_botline = lnum;
     }
 
-    // make sure the rest of the screen is blank
-    // write the 'eob' character to rows that aren't part of the file.
+    // Make sure the rest of the screen is blank.
+    // write the "eob" character from 'fillchars' to rows that aren't part
+    // of the file.
     win_draw_end(wp, wp->w_p_fcs_chars.eob, ' ', false, row, wp->w_grid.rows,
                  HLF_EOB);
   }
diff --git a/src/nvim/mbyte.c b/src/nvim/mbyte.c
index 83044f209a..ad8718742f 100644
--- a/src/nvim/mbyte.c
+++ b/src/nvim/mbyte.c
@@ -1989,8 +1989,7 @@ theend:
 }
 
 /// @return  true if string "s" is a valid utf-8 string.
-/// When "end" is NULL stop at the first NUL.
-/// When "end" is positive stop there.
+/// When "end" is NULL stop at the first NUL.  Otherwise stop at "end".
 bool utf_valid_string(const char_u *s, const char_u *end)
 {
   const char_u *p = s;
diff --git a/src/nvim/option.c b/src/nvim/option.c
index b2525b73a0..6912f93daa 100644
--- a/src/nvim/option.c
+++ b/src/nvim/option.c
@@ -4250,6 +4250,14 @@ void win_copy_options(win_T *wp_from, win_T *wp_to)
   didset_window_options(wp_to, true);
 }
 
+static char *copy_option_val(const char *val)
+{
+  if (val == empty_option) {
+    return empty_option;  // no need to allocate memory
+  }
+  return xstrdup(val);
+}
+
 /// Copy the options from one winopt_T to another.
 /// Doesn't free the old option values in "to", use clear_winopt() for that.
 /// The 'scroll' option is not copied, because it depends on the window height.
@@ -4258,21 +4266,23 @@ void copy_winopt(winopt_T *from, winopt_T *to)
 {
   to->wo_arab = from->wo_arab;
   to->wo_list = from->wo_list;
+  to->wo_lcs = copy_option_val(from->wo_lcs);
+  to->wo_fcs = copy_option_val(from->wo_fcs);
   to->wo_nu = from->wo_nu;
   to->wo_rnu = from->wo_rnu;
-  to->wo_ve = xstrdup(from->wo_ve);
+  to->wo_ve = copy_option_val(from->wo_ve);
   to->wo_ve_flags = from->wo_ve_flags;
   to->wo_nuw = from->wo_nuw;
   to->wo_rl  = from->wo_rl;
-  to->wo_rlc = xstrdup(from->wo_rlc);
-  to->wo_sbr = xstrdup(from->wo_sbr);
-  to->wo_stl = xstrdup(from->wo_stl);
-  to->wo_wbr = xstrdup(from->wo_wbr);
+  to->wo_rlc = copy_option_val(from->wo_rlc);
+  to->wo_sbr = copy_option_val(from->wo_sbr);
+  to->wo_stl = copy_option_val(from->wo_stl);
+  to->wo_wbr = copy_option_val(from->wo_wbr);
   to->wo_wrap = from->wo_wrap;
   to->wo_wrap_save = from->wo_wrap_save;
   to->wo_lbr = from->wo_lbr;
   to->wo_bri = from->wo_bri;
-  to->wo_briopt = xstrdup(from->wo_briopt);
+  to->wo_briopt = copy_option_val(from->wo_briopt);
   to->wo_scb = from->wo_scb;
   to->wo_scb_save = from->wo_scb_save;
   to->wo_crb = from->wo_crb;
@@ -4280,30 +4290,28 @@ void copy_winopt(winopt_T *from, winopt_T *to)
   to->wo_spell = from->wo_spell;
   to->wo_cuc = from->wo_cuc;
   to->wo_cul = from->wo_cul;
-  to->wo_culopt = xstrdup(from->wo_culopt);
-  to->wo_cc = xstrdup(from->wo_cc);
+  to->wo_culopt = copy_option_val(from->wo_culopt);
+  to->wo_cc = copy_option_val(from->wo_cc);
   to->wo_diff = from->wo_diff;
   to->wo_diff_saved = from->wo_diff_saved;
-  to->wo_cocu = xstrdup(from->wo_cocu);
+  to->wo_cocu = copy_option_val(from->wo_cocu);
   to->wo_cole = from->wo_cole;
-  to->wo_fdc = xstrdup(from->wo_fdc);
+  to->wo_fdc = copy_option_val(from->wo_fdc);
   to->wo_fdc_save = from->wo_diff_saved ? xstrdup(from->wo_fdc_save) : empty_option;
   to->wo_fen = from->wo_fen;
   to->wo_fen_save = from->wo_fen_save;
-  to->wo_fdi = xstrdup(from->wo_fdi);
+  to->wo_fdi = copy_option_val(from->wo_fdi);
   to->wo_fml = from->wo_fml;
   to->wo_fdl = from->wo_fdl;
   to->wo_fdl_save = from->wo_fdl_save;
-  to->wo_fdm = xstrdup(from->wo_fdm);
+  to->wo_fdm = copy_option_val(from->wo_fdm);
   to->wo_fdm_save = from->wo_diff_saved ? xstrdup(from->wo_fdm_save) : empty_option;
   to->wo_fdn = from->wo_fdn;
-  to->wo_fde = xstrdup(from->wo_fde);
-  to->wo_fdt = xstrdup(from->wo_fdt);
-  to->wo_fmr = xstrdup(from->wo_fmr);
-  to->wo_scl = xstrdup(from->wo_scl);
-  to->wo_winhl = xstrdup(from->wo_winhl);
-  to->wo_fcs = xstrdup(from->wo_fcs);
-  to->wo_lcs = xstrdup(from->wo_lcs);
+  to->wo_fde = copy_option_val(from->wo_fde);
+  to->wo_fdt = copy_option_val(from->wo_fdt);
+  to->wo_fmr = copy_option_val(from->wo_fmr);
+  to->wo_scl = copy_option_val(from->wo_scl);
+  to->wo_winhl = copy_option_val(from->wo_winhl);
   to->wo_winbl = from->wo_winbl;
 
   // Copy the script context so that we know were the value was last set.
@@ -4338,8 +4346,8 @@ static void check_winopt(winopt_T *wop)
   check_string_option(&wop->wo_cocu);
   check_string_option(&wop->wo_briopt);
   check_string_option(&wop->wo_winhl);
-  check_string_option(&wop->wo_fcs);
   check_string_option(&wop->wo_lcs);
+  check_string_option(&wop->wo_fcs);
   check_string_option(&wop->wo_ve);
   check_string_option(&wop->wo_wbr);
 }
@@ -4364,8 +4372,8 @@ void clear_winopt(winopt_T *wop)
   clear_string_option(&wop->wo_cocu);
   clear_string_option(&wop->wo_briopt);
   clear_string_option(&wop->wo_winhl);
-  clear_string_option(&wop->wo_fcs);
   clear_string_option(&wop->wo_lcs);
+  clear_string_option(&wop->wo_fcs);
   clear_string_option(&wop->wo_ve);
   clear_string_option(&wop->wo_wbr);
 }
diff --git a/src/nvim/option_defs.h b/src/nvim/option_defs.h
index ad8092add2..f9848cb792 100644
--- a/src/nvim/option_defs.h
+++ b/src/nvim/option_defs.h
@@ -972,8 +972,8 @@ enum {
   WV_WRAP,
   WV_SCL,
   WV_WINHL,
-  WV_FCS,
   WV_LCS,
+  WV_FCS,
   WV_WINBL,
   WV_WBR,
   WV_COUNT,  // must be the last one
diff --git a/src/nvim/optionstr.c b/src/nvim/optionstr.c
index e1538e0491..ec62c4b8ad 100644
--- a/src/nvim/optionstr.c
+++ b/src/nvim/optionstr.c
@@ -949,38 +949,30 @@ char *did_set_string_option(int opt_idx, char_u **varp, char_u *oldval, char *er
       }
       s = (char *)skip_to_option_part((char_u *)s);
     }
-  } else if (varp == &p_lcs) {  // global 'listchars'
-    errmsg = set_chars_option(curwin, varp, false);
+  } else if (varp == &p_lcs || varp == &p_fcs) {  // global 'listchars' or 'fillchars'
+    char **local_ptr = varp == &p_lcs ? &curwin->w_p_lcs : &curwin->w_p_fcs;
+    // only apply the global value to "curwin" when it does not have a local value
+    errmsg = set_chars_option(curwin, varp, **local_ptr == NUL || !(opt_flags & OPT_GLOBAL));
     if (errmsg == NULL) {
-      // The current window is set to use the global 'listchars' value.
-      // So clear the window-local value.
+      // If the current window is set to use the global
+      // 'listchars'/'fillchars' value, clear the window-local value.
       if (!(opt_flags & OPT_GLOBAL)) {
-        clear_string_option(&curwin->w_p_lcs);
+        clear_string_option(local_ptr);
       }
       FOR_ALL_TAB_WINDOWS(tp, wp) {
+        // If the current window has a local value need to apply it
+        // again, it was changed when setting the global value.
         // If no error was returned above, we don't expect an error
         // here, so ignore the return value.
-        (void)set_chars_option(wp, (char_u **)&wp->w_p_lcs, true);
+        local_ptr = varp == &p_lcs ? &wp->w_p_lcs : &wp->w_p_fcs;
+        if (**local_ptr == NUL) {
+          (void)set_chars_option(wp, (char_u **)local_ptr, true);
+        }
       }
       redraw_all_later(UPD_NOT_VALID);
     }
   } else if (varp == (char_u **)&curwin->w_p_lcs) {  // local 'listchars'
     errmsg = set_chars_option(curwin, varp, true);
-  } else if (varp == &p_fcs) {  // global 'fillchars'
-    errmsg = set_chars_option(curwin, varp, false);
-    if (errmsg == NULL) {
-      // The current window is set to use the global 'fillchars' value.
-      // So clear the window-local value.
-      if (!(opt_flags & OPT_GLOBAL)) {
-        clear_string_option(&curwin->w_p_fcs);
-      }
-      FOR_ALL_TAB_WINDOWS(tp, wp) {
-        // If no error was returned above, we don't expect an error
-        // here, so ignore the return value.
-        (void)set_chars_option(wp, (char_u **)&wp->w_p_fcs, true);
-      }
-      redraw_all_later(UPD_NOT_VALID);
-    }
   } else if (varp == (char_u **)&curwin->w_p_fcs) {  // local 'fillchars'
     errmsg = set_chars_option(curwin, varp, true);
   } else if (varp == &p_cedit) {  // 'cedit'
diff --git a/src/nvim/screen.c b/src/nvim/screen.c
index 2ed31ae8a9..43c85bedb5 100644
--- a/src/nvim/screen.c
+++ b/src/nvim/screen.c
@@ -1262,17 +1262,15 @@ int number_width(win_T *wp)
 /// Calls mb_cptr2char_adv(p) and returns the character.
 /// If "p" starts with "\x", "\u" or "\U" the hex or unicode value is used.
 /// Returns 0 for invalid hex or invalid UTF-8 byte.
-static int get_encoded_char_adv(char_u **p)
+static int get_encoded_char_adv(const char_u **p)
 {
-  char_u *s = *p;
+  const char_u *s = *p;
 
   if (s[0] == '\\' && (s[1] == 'x' || s[1] == 'u' || s[1] == 'U')) {
     int64_t num = 0;
-    int bytes;
-    int n;
-    for (bytes = s[1] == 'x' ? 1 : s[1] == 'u' ? 2 : 4; bytes > 0; bytes--) {
+    for (int bytes = s[1] == 'x' ? 1 : s[1] == 'u' ? 2 : 4; bytes > 0; bytes--) {
       *p += 2;
-      n = hexhex2nr(*p);
+      int n = hexhex2nr(*p);
       if (n < 0) {
         return 0;
       }
@@ -1283,8 +1281,8 @@ static int get_encoded_char_adv(char_u **p)
   }
 
   // TODO(bfredl): use schar_T representation and utfc_ptr2len
-  int clen = utf_ptr2len((char *)s);
-  int c = mb_cptr2char_adv((const char_u **)p);
+  int clen = utf_ptr2len((const char *)s);
+  int c = mb_cptr2char_adv(p);
   if (clen == 1 && c > 127) {  // Invalid UTF-8 byte
     return 0;
   }
@@ -1294,26 +1292,22 @@ static int get_encoded_char_adv(char_u **p)
 /// Handle setting 'listchars' or 'fillchars'.
 /// Assume monocell characters
 ///
-/// @param varp either &curwin->w_p_lcs or &curwin->w_p_fcs
+/// @param varp   either the global or the window-local value.
+/// @param apply  if false, do not store the flags, only check for errors.
 /// @return error message, NULL if it's OK.
-char *set_chars_option(win_T *wp, char_u **varp, bool set)
+char *set_chars_option(win_T *wp, char_u **varp, bool apply)
 {
-  int round, i, len, len2, entries;
-  char_u *p, *s;
-  int c1;
-  int c2 = 0;
-  int c3 = 0;
-  char_u *last_multispace = NULL;   // Last occurrence of "multispace:"
-  char_u *last_lmultispace = NULL;  // Last occurrence of "leadmultispace:"
+  const char_u *last_multispace = NULL;   // Last occurrence of "multispace:"
+  const char_u *last_lmultispace = NULL;  // Last occurrence of "leadmultispace:"
   int multispace_len = 0;           // Length of lcs-multispace string
   int lead_multispace_len = 0;      // Length of lcs-leadmultispace string
+  const bool is_listchars = (varp == &p_lcs || varp == (char_u **)&wp->w_p_lcs);
 
   struct chars_tab {
-    int *cp;    ///< char value
+    int *cp;     ///< char value
     char *name;  ///< char id
-    int def;    ///< default value
+    int def;     ///< default value
   };
-  struct chars_tab *tab;
 
   // XXX: Characters taking 2 columns is forbidden (TUI limitation?). Set old defaults in this case.
   struct chars_tab fcs_tab[] = {
@@ -1335,6 +1329,7 @@ char *set_chars_option(win_T *wp, char_u **varp, bool set)
     { &wp->w_p_fcs_chars.msgsep,     "msgsep",    ' ' },
     { &wp->w_p_fcs_chars.eob,        "eob",       '~' },
   };
+
   struct chars_tab lcs_tab[] = {
     { &wp->w_p_lcs_chars.eol,     "eol",      NUL },
     { &wp->w_p_lcs_chars.ext,     "extends",  NUL },
@@ -1347,30 +1342,33 @@ char *set_chars_option(win_T *wp, char_u **varp, bool set)
     { &wp->w_p_lcs_chars.conceal, "conceal",  NUL },
   };
 
-  if (varp == &p_lcs || varp == (char_u **)&wp->w_p_lcs) {
+  struct chars_tab *tab;
+  int entries;
+  const char_u *value = *varp;
+  if (is_listchars) {
     tab = lcs_tab;
     entries = ARRAY_SIZE(lcs_tab);
     if (varp == (char_u **)&wp->w_p_lcs && wp->w_p_lcs[0] == NUL) {
-      varp = &p_lcs;
+      value = p_lcs;  // local value is empty, use the global value
     }
   } else {
     tab = fcs_tab;
     entries = ARRAY_SIZE(fcs_tab);
     if (varp == (char_u **)&wp->w_p_fcs && wp->w_p_fcs[0] == NUL) {
-      varp = &p_fcs;
+      value = p_fcs;  // local value is empty, use the global value
     }
   }
 
   // first round: check for valid value, second round: assign values
-  for (round = 0; round <= (set ? 1 : 0); round++) {
+  for (int round = 0; round <= (apply ? 1 : 0); round++) {
     if (round > 0) {
       // After checking that the value is valid: set defaults
-      for (i = 0; i < entries; i++) {
+      for (int i = 0; i < entries; i++) {
         if (tab[i].cp != NULL) {
           *(tab[i].cp) = tab[i].def;
         }
       }
-      if (varp == &p_lcs || varp == (char_u **)&wp->w_p_lcs) {
+      if (is_listchars) {
         wp->w_p_lcs_chars.tab1 = NUL;
         wp->w_p_lcs_chars.tab3 = NUL;
 
@@ -1392,19 +1390,20 @@ char *set_chars_option(win_T *wp, char_u **varp, bool set)
         }
       }
     }
-    p = *varp;
+    const char_u *p = value;
     while (*p) {
+      int i;
       for (i = 0; i < entries; i++) {
-        len = (int)STRLEN(tab[i].name);
+        const size_t len = STRLEN(tab[i].name);
         if (STRNCMP(p, tab[i].name, len) == 0
             && p[len] == ':'
             && p[len + 1] != NUL) {
-          c2 = c3 = 0;
-          s = p + len + 1;
-          c1 = get_encoded_char_adv(&s);
+          const char_u *s = p + len + 1;
+          int c1 = get_encoded_char_adv(&s);
           if (c1 == 0 || char2cells(c1) > 1) {
             return e_invarg;
           }
+          int c2 = 0, c3 = 0;
           if (tab[i].cp == &wp->w_p_lcs_chars.tab2) {
             if (*s == NUL) {
               return e_invarg;
@@ -1437,19 +1436,19 @@ char *set_chars_option(win_T *wp, char_u **varp, bool set)
       }
 
       if (i == entries) {
-        len = (int)STRLEN("multispace");
-        len2 = (int)STRLEN("leadmultispace");
-        if ((varp == &p_lcs || varp == (char_u **)&wp->w_p_lcs)
+        const size_t len = STRLEN("multispace");
+        const size_t len2 = STRLEN("leadmultispace");
+        if (is_listchars
             && STRNCMP(p, "multispace", len) == 0
             && p[len] == ':'
             && p[len + 1] != NUL) {
-          s = p + len + 1;
+          const char_u *s = p + len + 1;
           if (round == 0) {
             // Get length of lcs-multispace string in the first round
             last_multispace = p;
             multispace_len = 0;
             while (*s != NUL && *s != ',') {
-              c1 = get_encoded_char_adv(&s);
+              int c1 = get_encoded_char_adv(&s);
               if (c1 == 0 || char2cells(c1) > 1) {
                 return e_invarg;
               }
@@ -1463,24 +1462,24 @@ char *set_chars_option(win_T *wp, char_u **varp, bool set)
           } else {
             int multispace_pos = 0;
             while (*s != NUL && *s != ',') {
-              c1 = get_encoded_char_adv(&s);
+              int c1 = get_encoded_char_adv(&s);
               if (p == last_multispace) {
                 wp->w_p_lcs_chars.multispace[multispace_pos++] = c1;
               }
             }
             p = s;
           }
-        } else if ((varp == &p_lcs || varp == (char_u **)&wp->w_p_lcs)
+        } else if (is_listchars
                    && STRNCMP(p, "leadmultispace", len2) == 0
                    && p[len2] == ':'
                    && p[len2 + 1] != NUL) {
-          s = p + len2 + 1;
+          const char_u *s = p + len2 + 1;
           if (round == 0) {
             // get length of lcs-leadmultispace string in first round
             last_lmultispace = p;
             lead_multispace_len = 0;
             while (*s != NUL && *s != ',') {
-              c1 = get_encoded_char_adv(&s);
+              int c1 = get_encoded_char_adv(&s);
               if (c1 == 0 || char2cells(c1) > 1) {
                 return e_invarg;
               }
@@ -1494,7 +1493,7 @@ char *set_chars_option(win_T *wp, char_u **varp, bool set)
           } else {
             int multispace_pos = 0;
             while (*s != NUL && *s != ',') {
-              c1 = get_encoded_char_adv(&s);
+              int c1 = get_encoded_char_adv(&s);
               if (p == last_lmultispace) {
                 wp->w_p_lcs_chars.leadmultispace[multispace_pos++] = c1;
               }
@@ -1505,6 +1504,7 @@ char *set_chars_option(win_T *wp, char_u **varp, bool set)
           return e_invarg;
         }
       }
+
       if (*p == ',') {
         p++;
       }
diff --git a/src/nvim/testdir/runtest.vim b/src/nvim/testdir/runtest.vim
index 206f335751..ce23141c7a 100644
--- a/src/nvim/testdir/runtest.vim
+++ b/src/nvim/testdir/runtest.vim
@@ -425,7 +425,7 @@ for s:test in sort(s:tests)
   set belloff=all
   let prev_error = ''
   let total_errors = []
-  let run_nr = 1
+  let g:run_nr = 1
 
   " A test can set g:test_is_flaky to retry running the test.
   let g:test_is_flaky = 0
@@ -444,10 +444,10 @@ for s:test in sort(s:tests)
       call add(s:messages, 'Found errors in ' . s:test . ':')
       call extend(s:messages, v:errors)
 
-      call add(total_errors, 'Run ' . run_nr . ':')
+      call add(total_errors, 'Run ' . g:run_nr . ':')
       call extend(total_errors, v:errors)
 
-      if run_nr == 5 || prev_error == v:errors[0]
+      if g:run_nr >= 5 || prev_error == v:errors[0]
         call add(total_errors, 'Flaky test failed too often, giving up')
         let v:errors = total_errors
         break
@@ -462,7 +462,7 @@ for s:test in sort(s:tests)
 
       let prev_error = v:errors[0]
       let v:errors = []
-      let run_nr += 1
+      let g:run_nr += 1
 
       call RunTheTest(s:test)
 
diff --git a/src/nvim/testdir/setup.vim b/src/nvim/testdir/setup.vim
index 6bc3607b69..472ed4ca14 100644
--- a/src/nvim/testdir/setup.vim
+++ b/src/nvim/testdir/setup.vim
@@ -5,7 +5,7 @@ if exists('s:did_load')
   set directory&
   set directory^=.
   set display=
-  set fillchars=vert:\|,fold:-
+  set fillchars=vert:\|,foldsep:\|,fold:-
   set formatoptions=tcq
   set fsync
   set laststatus=1
diff --git a/src/nvim/testdir/test_display.vim b/src/nvim/testdir/test_display.vim
index 6938abbc28..217bb5d781 100644
--- a/src/nvim/testdir/test_display.vim
+++ b/src/nvim/testdir/test_display.vim
@@ -309,6 +309,88 @@ func Test_eob_fillchars()
   close
 endfunc
 
+" Test for 'foldopen', 'foldclose' and 'foldsep' in 'fillchars'
+func Test_fold_fillchars()
+  new
+  set fdc=2 foldenable foldmethod=manual
+  call setline(1, ['one', 'two', 'three', 'four', 'five'])
+  2,4fold
+  " First check for the default setting for a closed fold
+  let lines = ScreenLines([1, 3], 8)
+  let expected = [
+        \ '  one   ',
+        \ '+ +--  3',
+        \ '  five  '
+        \ ]
+  call assert_equal(expected, lines)
+  normal 2Gzo
+  " check the characters for an open fold
+  let lines = ScreenLines([1, 5], 8)
+  let expected = [
+        \ '  one   ',
+        \ '- two   ',
+        \ '| three ',
+        \ '| four  ',
+        \ '  five  '
+        \ ]
+  call assert_equal(expected, lines)
+
+  " change the setting
+  set fillchars=vert:\|,fold:-,eob:~,foldopen:[,foldclose:],foldsep:-
+
+  " check the characters for an open fold
+  let lines = ScreenLines([1, 5], 8)
+  let expected = [
+        \ '  one   ',
+        \ '[ two   ',
+        \ '- three ',
+        \ '- four  ',
+        \ '  five  '
+        \ ]
+  call assert_equal(expected, lines)
+
+  " check the characters for a closed fold
+  normal 2Gzc
+  let lines = ScreenLines([1, 3], 8)
+  let expected = [
+        \ '  one   ',
+        \ '] +--  3',
+        \ '  five  '
+        \ ]
+  call assert_equal(expected, lines)
+
+  %bw!
+  set fillchars& fdc& foldmethod& foldenable&
+endfunc
+
+func Test_local_fillchars()
+  CheckScreendump
+
+  let lines =<< trim END
+      call setline(1, ['window 1']->repeat(3))
+      setlocal fillchars=stl:1,stlnc:a,vert:=,eob:x
+      vnew
+      call setline(1, ['window 2']->repeat(3))
+      setlocal fillchars=stl:2,stlnc:b,vert:+,eob:y
+      new
+      wincmd J
+      call setline(1, ['window 3']->repeat(3))
+      setlocal fillchars=stl:3,stlnc:c,vert:<,eob:z
+      vnew
+      call setline(1, ['window 4']->repeat(3))
+      setlocal fillchars=stl:4,stlnc:d,vert:>,eob:o
+  END
+  call writefile(lines, 'Xdisplayfillchars')
+  let buf = RunVimInTerminal('-S Xdisplayfillchars', #{rows: 12})
+  call VerifyScreenDump(buf, 'Test_display_fillchars_1', {})
+
+  call term_sendkeys(buf, ":wincmd k\r")
+  call VerifyScreenDump(buf, 'Test_display_fillchars_2', {})
+
+  call StopVimInTerminal(buf)
+  call delete('Xdisplayfillchars')
+endfunc
+
 func Test_display_linebreak_breakat()
   new
   vert resize 25