1 files changed, 37 insertions, 15 deletions

diff --git a/src/nvim/message.c b/src/nvim/message.c
index 71cb345878..a34b895033 100644
--- a/src/nvim/message.c
+++ b/src/nvim/message.c
@@ -131,7 +131,7 @@ static int msg_grid_scroll_discount = 0;
 
 static void ui_ext_msg_set_pos(int row, bool scrolled)
 {
-  char buf[MAX_MCO];
+  char buf[MAX_MCO + 1];
   size_t size = utf_char2bytes(curwin->w_p_fcs_chars.msgsep, (char_u *)buf);
   buf[size] = '\0';
   ui_call_msg_set_pos(msg_grid.handle, row, scrolled,
@@ -869,18 +869,18 @@ char_u *msg_trunc_attr(char_u *s, int force, int attr)
  */
 char_u *msg_may_trunc(int force, char_u *s)
 {
-  int n;
   int room;
 
   room = (int)(Rows - cmdline_row - 1) * Columns + sc_col - 1;
   if ((force || (shortmess(SHM_TRUNC) && !exmode_active))
-      && (n = (int)STRLEN(s) - room) > 0) {
+      && (int)STRLEN(s) - room > 0) {
     int size = vim_strsize(s);
 
     // There may be room anyway when there are multibyte chars.
     if (size <= room) {
       return s;
     }
+    int n;
     for (n = 0; size >= room; ) {
       size -= utf_ptr2cells(s + n);
       n += utfc_ptr2len(s + n);
@@ -1193,7 +1193,8 @@ void wait_return(int redraw)
              || c == K_MIDDLEDRAG || c == K_MIDDLERELEASE
              || c == K_RIGHTDRAG  || c == K_RIGHTRELEASE
              || c == K_MOUSELEFT  || c == K_MOUSERIGHT
-             || c == K_MOUSEDOWN  || c == K_MOUSEUP);
+             || c == K_MOUSEDOWN  || c == K_MOUSEUP
+             || c == K_MOUSEMOVE);
     os_breakcheck();
     /*
      * Avoid that the mouse-up event causes visual mode to start.
@@ -1705,6 +1706,7 @@ void msg_prt_line(char_u *s, int list)
   char_u *p_extra = NULL;  // init to make SASC shut up
   int n;
   int attr = 0;
+  char_u *lead = NULL;
   char_u *trail = NULL;
   int l;
 
@@ -1712,11 +1714,24 @@ void msg_prt_line(char_u *s, int list)
     list = true;
   }
 
-  // find start of trailing whitespace
-  if (list && curwin->w_p_lcs_chars.trail) {
-    trail = s + STRLEN(s);
-    while (trail > s && ascii_iswhite(trail[-1])) {
-      trail--;
+  if (list) {
+    // find start of trailing whitespace
+    if (curwin->w_p_lcs_chars.trail) {
+      trail = s + STRLEN(s);
+      while (trail > s && ascii_iswhite(trail[-1])) {
+        trail--;
+      }
+    }
+    // find end of leading whitespace
+    if (curwin->w_p_lcs_chars.lead) {
+      lead = s;
+      while (ascii_iswhite(lead[0])) {
+        lead++;
+      }
+      // in a line full of spaces all of them are treated as trailing
+      if (*lead == NUL) {
+        lead = NULL;
+      }
     }
   }
 
@@ -1758,7 +1773,9 @@ void msg_prt_line(char_u *s, int list)
       c = *s++;
       if (c == TAB && (!list || curwin->w_p_lcs_chars.tab1)) {
         // tab amount depends on current column
-        n_extra = curbuf->b_p_ts - col % curbuf->b_p_ts - 1;
+        n_extra = tabstop_padding(col,
+                                  curbuf->b_p_ts,
+                                  curbuf->b_p_vts_array) - 1;
         if (!list) {
           c = ' ';
           c_extra = ' ';
@@ -1791,6 +1808,9 @@ void msg_prt_line(char_u *s, int list)
         /* Use special coloring to be able to distinguish <hex> from
          * the same in plain text. */
         attr = HL_ATTR(HLF_8);
+      } else if (c == ' ' && lead != NULL && s <= lead) {
+        c = curwin->w_p_lcs_chars.lead;
+        attr = HL_ATTR(HLF_8);
       } else if (c == ' ' && trail != NULL && s > trail) {
         c = curwin->w_p_lcs_chars.trail;
         attr = HL_ATTR(HLF_8);
@@ -2246,12 +2266,14 @@ void msg_scroll_up(bool may_throttle)
 /// per screen update.
 ///
 /// NB: The bookkeeping is quite messy, and rests on a bunch of poorly
-/// documented assumtions. For instance that the message area always grows while
-/// being throttled, messages are only being output on the last line etc.
+/// documented assumptions. For instance that the message area always grows
+/// while being throttled, messages are only being output on the last line
+/// etc.
 ///
-/// Probably message scrollback storage should reimplented as a file_buffer, and
-/// message scrolling in TUI be reimplemented as a modal floating window. Then
-/// we get throttling "for free" using standard redraw_later code paths.
+/// Probably message scrollback storage should be reimplemented as a
+/// file_buffer, and message scrolling in TUI be reimplemented as a modal
+/// floating window. Then we get throttling "for free" using standard
+/// redraw_later code paths.
 void msg_scroll_flush(void)
 {
   if (msg_grid.throttled) {