vim-patch:9.1.0557: moving in the buffer list doesn't work as documented (#29653)

Problem:  moving in the buffer list doesn't work as documented
          (SenileFelineS)
Solution: Skip non-help buffers, when run from normal buffers, else
          only move from help buffers to the next help buffer (LemonBoy)

As explained in the help section for :bnext and :bprev the commands
should jump from help buffers to help buffers (and from regular ones to
regular ones).

fixes: vim/vim#4478
closes: vim/vim#15198

https://github.com/vim/vim/commit/893eeeb44583ca33276e263165b2a6e50fd297d0

Co-authored-by: LemonBoy <thatlemon@gmail.com>

1 files changed, 39 insertions, 12 deletions

diff --git a/src/nvim/buffer.c b/src/nvim/buffer.c
index d894844c6d..d1b7c553c3 100644
--- a/src/nvim/buffer.c
+++ b/src/nvim/buffer.c
@@ -942,6 +942,21 @@ static void free_buffer_stuff(buf_T *buf, int free_flags)
 void goto_buffer(exarg_T *eap, int start, int dir, int count)
 {
   const int save_sea = swap_exists_action;
+  bool skip_help_buf;
+
+  switch (eap->cmdidx) {
+  case CMD_bnext:
+  case CMD_sbnext:
+  case CMD_bNext:
+  case CMD_bprevious:
+  case CMD_sbNext:
+  case CMD_sbprevious:
+    skip_help_buf = true;
+    break;
+  default:
+    skip_help_buf = false;
+    break;
+  }
 
   bufref_T old_curbuf;
   set_bufref(&old_curbuf, curbuf);
@@ -949,8 +964,9 @@ void goto_buffer(exarg_T *eap, int start, int dir, int count)
   if (swap_exists_action == SEA_NONE) {
     swap_exists_action = SEA_DIALOG;
   }
-  do_buffer(*eap->cmd == 's' ? DOBUF_SPLIT : DOBUF_GOTO,
-            start, dir, count, eap->forceit);
+  (void)do_buffer_ext(*eap->cmd == 's' ? DOBUF_SPLIT : DOBUF_GOTO, start, dir, count,
+                      (eap->forceit ? DOBUF_FORCEIT : 0) |
+                      (skip_help_buf ? DOBUF_SKIPHELP : 0));
 
   if (swap_exists_action == SEA_QUIT && *eap->cmd == 's') {
     cleanup_T cs;
@@ -1202,10 +1218,10 @@ static int empty_curbuf(bool close_others, int forceit, int action)
 ///
 /// @param dir  FORWARD or BACKWARD
 /// @param count  buffer number or number of buffers
-/// @param forceit  true for :...!
+/// @param flags  see @ref dobuf_flags_value
 ///
 /// @return  FAIL or OK.
-int do_buffer(int action, int start, int dir, int count, int forceit)
+static int do_buffer_ext(int action, int start, int dir, int count, int flags)
 {
   buf_T *buf;
   buf_T *bp;
@@ -1257,8 +1273,12 @@ int do_buffer(int action, int start, int dir, int count, int forceit)
           buf = lastbuf;
         }
       }
-      // don't count unlisted buffers
-      if (unload || buf->b_p_bl) {
+      // Don't count unlisted buffers.
+      // Avoid non-help buffers if the starting point was a non-help buffer and
+      // vice-versa.
+      if (unload
+          || (buf->b_p_bl
+              && ((flags & DOBUF_SKIPHELP) == 0 || buf->b_help == bp->b_help))) {
         count--;
         bp = NULL;              // use this buffer as new starting point
       }
@@ -1284,7 +1304,9 @@ int do_buffer(int action, int start, int dir, int count, int forceit)
     return FAIL;
   }
 
-  if (action == DOBUF_GOTO && buf != curbuf && !check_can_set_curbuf_forceit(forceit)) {
+  if (action == DOBUF_GOTO
+      && buf != curbuf
+      && !check_can_set_curbuf_forceit((flags & DOBUF_FORCEIT) ? true : false)) {
     // disallow navigating to another buffer when 'winfixbuf' is applied
     return FAIL;
   }
@@ -1310,7 +1332,7 @@ int do_buffer(int action, int start, int dir, int count, int forceit)
       return FAIL;
     }
 
-    if (!forceit && bufIsChanged(buf)) {
+    if ((flags & DOBUF_FORCEIT) == 0 && bufIsChanged(buf)) {
       if ((p_confirm || (cmdmod.cmod_flags & CMOD_CONFIRM)) && p_write) {
         dialog_changed(buf, false);
         if (!bufref_valid(&bufref)) {
@@ -1330,7 +1352,7 @@ int do_buffer(int action, int start, int dir, int count, int forceit)
       }
     }
 
-    if (!forceit && buf->terminal && terminal_running(buf->terminal)) {
+    if (!(flags & DOBUF_FORCEIT) && buf->terminal && terminal_running(buf->terminal)) {
       if (p_confirm || (cmdmod.cmod_flags & CMOD_CONFIRM)) {
         if (!dialog_close_terminal(buf)) {
           return FAIL;
@@ -1358,7 +1380,7 @@ int do_buffer(int action, int start, int dir, int count, int forceit)
       }
     }
     if (bp == NULL && buf == curbuf) {
-      return empty_curbuf(true, forceit, action);
+      return empty_curbuf(true, (flags & DOBUF_FORCEIT), action);
     }
 
     // If the deleted buffer is the current one, close the current window
@@ -1516,7 +1538,7 @@ int do_buffer(int action, int start, int dir, int count, int forceit)
   if (buf == NULL) {
     // Autocommands must have wiped out all other buffers.  Only option
     // now is to make the current buffer empty.
-    return empty_curbuf(false, forceit, action);
+    return empty_curbuf(false, (flags & DOBUF_FORCEIT), action);
   }
 
   // make "buf" the current buffer
@@ -1537,7 +1559,7 @@ int do_buffer(int action, int start, int dir, int count, int forceit)
   }
 
   // Check if the current buffer may be abandoned.
-  if (action == DOBUF_GOTO && !can_abandon(curbuf, forceit)) {
+  if (action == DOBUF_GOTO && !can_abandon(curbuf, (flags & DOBUF_FORCEIT))) {
     if ((p_confirm || (cmdmod.cmod_flags & CMOD_CONFIRM)) && p_write) {
       bufref_T bufref;
       set_bufref(&bufref, buf);
@@ -1567,6 +1589,11 @@ int do_buffer(int action, int start, int dir, int count, int forceit)
   return OK;
 }
 
+int do_buffer(int action, int start, int dir, int count, int forceit)
+{
+  return do_buffer_ext(action, start, dir, count, forceit ? DOBUF_FORCEIT : 0);
+}
+
 /// Set current buffer to "buf".  Executes autocommands and closes current
 /// buffer.
 ///