vim-patch:9.1.0956: completion may crash, completion highlight wrong with preview window

Problem:  completion may crash, completion highlight wrong with preview
          window (after v9.1.0954)
Solution: correctly calculate scroll offset, check for preview window
          when adding extra highlighting
          (glepnir)

when there have a preview window prepare_tagpreview
will change curwin to preview window and this may cause
ComplMatchIns check condition not correct. check wp is curwin
and also the type of wp is not a preview or poup info

fixes: https://github.com/vim/vim/issues/16284
closes: https://github.com/vim/vim/pull/16283

https://github.com/vim/vim/commit/8d0bb6dc9f2e5d94ebb59671d592c1b7fa325ca6

5 files changed, 51 insertions, 7 deletions

diff --git a/src/nvim/drawline.c b/src/nvim/drawline.c
index 35a41f840d..3062b0f2a3 100644
--- a/src/nvim/drawline.c
+++ b/src/nvim/drawline.c
@@ -1495,7 +1495,7 @@ int win_line(win_T *wp, linenr_T lnum, int startrow, int endrow, int col_rows, s
     ptr = line + v;  // "line" may have been updated
   }
 
-  if ((State & MODE_INSERT) && in_curline && ins_compl_active()) {
+  if ((State & MODE_INSERT) && in_curline && ins_compl_win_active(wp)) {
     area_highlighting = true;
   }
 
@@ -1746,7 +1746,7 @@ int win_line(win_T *wp, linenr_T lnum, int startrow, int endrow, int col_rows, s
         }
 
         // Check if ComplMatchIns highlight is needed.
-        if ((State & MODE_INSERT) && in_curline && ins_compl_active()) {
+        if ((State & MODE_INSERT) && in_curline && ins_compl_win_active(wp)) {
           int ins_match_attr = ins_compl_col_range_attr((int)(ptr - line));
           if (ins_match_attr > 0) {
             search_attr = hl_combine_attr(search_attr, ins_match_attr);
diff --git a/src/nvim/insexpand.c b/src/nvim/insexpand.c
index aee3603d75..7245b0d6ce 100644
--- a/src/nvim/insexpand.c
+++ b/src/nvim/insexpand.c
@@ -1722,6 +1722,12 @@ bool ins_compl_active(void)
   return compl_started;
 }
 
+/// Return true when wp is the actual completion window
+bool ins_compl_win_active(win_T *wp)
+{
+  return ins_compl_active() && !(wp->w_p_pvw || wp->w_float_is_info);
+}
+
 /// Selected one of the matches.  When false the match was edited or using the
 /// longest common string.
 bool ins_compl_used_match(void)
diff --git a/src/nvim/popupmenu.c b/src/nvim/popupmenu.c
index 70a479239e..75e5a52829 100644
--- a/src/nvim/popupmenu.c
+++ b/src/nvim/popupmenu.c
@@ -906,10 +906,10 @@ static bool pum_set_selected(int n, int repeat)
 {
   bool resized = false;
   int context = pum_height / 2;
-  int scroll_offset = pum_selected - pum_height;
   int prev_selected = pum_selected;
 
   pum_selected = n;
+  int scroll_offset = pum_selected - pum_height;
   unsigned cur_cot_flags = get_cot_flags();
   bool use_float = (cur_cot_flags & kOptCotFlagPopup) != 0;
 
@@ -940,7 +940,7 @@ static bool pum_set_selected(int n, int repeat)
       // scroll up; when we did a jump it's probably a PageDown then
       // scroll a whole page
       if (pum_first < scroll_offset + 3) {
-        pum_first = MAX(pum_first, scroll_offset + 1);
+        pum_first = MAX(pum_first + pum_height - 2, scroll_offset + 1);
       } else {
         pum_first = scroll_offset + 1;
       }
@@ -953,7 +953,7 @@ static bool pum_set_selected(int n, int repeat)
       if (pum_first > pum_selected - context) {
         pum_first = MAX(pum_selected - context, 0);  // scroll down
       } else if (pum_first < pum_selected + context - pum_height + 1) {
-        pum_first = pum_selected + context - pum_height + 1; // up
+        pum_first = pum_selected + context - pum_height + 1;  // up
       }
     }
     // adjust for the number of lines displayed
diff --git a/test/functional/ui/popupmenu_spec.lua b/test/functional/ui/popupmenu_spec.lua
index 75421c6998..d1228d3607 100644
--- a/test/functional/ui/popupmenu_spec.lua
+++ b/test/functional/ui/popupmenu_spec.lua
@@ -5567,11 +5567,15 @@ describe('builtin popupmenu', function()
       -- oldtest: Test_pum_matchins_highlight()
       it('with ComplMatchIns highlight', function()
         exec([[
+          let g:change = 0
           func Omni_test(findstart, base)
             if a:findstart
               return col(".")
             endif
-            return [#{word: "foo"}, #{word: "bar"}, #{word: "你好"}]
+            if g:change == 0
+              return [#{word: "foo"}, #{word: "bar"}, #{word: "你好"}]
+            endif
+            return [#{word: "foo", info: "info"}, #{word: "bar"}, #{word: "你好"}]
           endfunc
           set omnifunc=Omni_test
           hi ComplMatchIns guifg=red
@@ -5663,6 +5667,21 @@ describe('builtin popupmenu', function()
           {2:-- INSERT --}                    |
         ]])
         feed('<Esc>')
+
+        feed(':let g:change=1<CR>S<C-X><C-O>')
+        screen:expect([[
+          info                            |
+          {1:~                               }|*2
+          {3:[Scratch] [Preview]             }|
+          {8:foo}^                             |
+          {s:foo            }{1:                 }|
+          {n:bar            }{1:                 }|
+          {n:你好           }{1:                 }|
+          {1:~                               }|*10
+          {4:[No Name] [+]                   }|
+          {2:-- }{5:match 1 of 3}                 |
+        ]])
+        feed('<Esc>')
       end)
 
       -- oldtest: Test_pum_matchins_highlight_combine()
diff --git a/test/old/testdir/test_popup.vim b/test/old/testdir/test_popup.vim
index f16a897b07..e902ea3bc2 100644
--- a/test/old/testdir/test_popup.vim
+++ b/test/old/testdir/test_popup.vim
@@ -1716,11 +1716,15 @@ endfunc
 func Test_pum_matchins_highlight()
   CheckScreendump
   let lines =<< trim END
+    let g:change = 0
     func Omni_test(findstart, base)
       if a:findstart
         return col(".")
       endif
-      return [#{word: "foo"}, #{word: "bar"}, #{word: "你好"}]
+      if g:change == 0
+        return [#{word: "foo"}, #{word: "bar"}, #{word: "你好"}]
+      endif
+      return [#{word: "foo", info: "info"}, #{word: "bar"}, #{word: "你好"}]
     endfunc
     set omnifunc=Omni_test
     hi ComplMatchIns ctermfg=red
@@ -1767,6 +1771,10 @@ func Test_pum_matchins_highlight()
   call VerifyScreenDump(buf, 'Test_pum_matchins_10', {})
   call term_sendkeys(buf, "\<Esc>")
 
+  call term_sendkeys(buf, ":let g:change=1\<CR>S\<C-X>\<C-O>")
+  call VerifyScreenDump(buf, 'Test_pum_matchins_11', {})
+  call term_sendkeys(buf, "\<Esc>")
+
   call StopVimInTerminal(buf)
 endfunc
 
@@ -1812,4 +1820,15 @@ func Test_pum_matchins_highlight_combine()
   call StopVimInTerminal(buf)
 endfunc
 
+" this used to crash
+func Test_popup_completion_many_ctrlp()
+  new
+  let candidates=repeat(['a0'], 99)
+  call setline(1, candidates)
+  exe ":norm! VGg\<C-A>"
+  norm! G
+  call feedkeys("o" .. repeat("\<c-p>", 100), 'tx')
+  bw!
+endfunc
+
 " vim: shiftwidth=2 sts=2 expandtab