fix(popup): wrong extmark data sync when lines changed in popup preview #30246

Problem: when popup preview buffer has filetype like markdown and ts
is enabled, the extmark clean and update not correct, if add the extmark
sync there has lots of duplicate codes like nvim_buf_set_lines.

Solution: use nvim_buf_set_lines api internally to set info to popup
preview buffer.

2 files changed, 137 insertions, 38 deletions

diff --git a/src/nvim/popupmenu.c b/src/nvim/popupmenu.c
index 75e5a52829..2b1dd22b1a 100644
--- a/src/nvim/popupmenu.c
+++ b/src/nvim/popupmenu.c
@@ -7,6 +7,7 @@
 #include <stdint.h>
 #include <string.h>
 
+#include "nvim/api/buffer.h"
 #include "nvim/api/private/defs.h"
 #include "nvim/api/private/helpers.h"
 #include "nvim/ascii_defs.h"
@@ -32,6 +33,7 @@
 #include "nvim/highlight_defs.h"
 #include "nvim/insexpand.h"
 #include "nvim/keycodes.h"
+#include "nvim/mark.h"
 #include "nvim/mbyte.h"
 #include "nvim/memline.h"
 #include "nvim/memory.h"
@@ -787,36 +789,41 @@ void pum_redraw(void)
   }
 }
 
-/// set info text to preview buffer.
+/// Set the informational text in the preview buffer when the completion
+/// item does not include a dedicated preview or popup window.
+///
+/// @param[in]  buf        Buffer where the text will be set.
+/// @param[in]  info       Informational text to display in the preview buffer.
+/// @param[in]  lnum       Where to start the text. Incremented for each added line.
+/// @param[out] max_width  Maximum width of the displayed text.
 static void pum_preview_set_text(buf_T *buf, char *info, linenr_T *lnum, int *max_width)
 {
-  bcount_t inserted_bytes = 0;
-  for (char *p = info; *p != NUL;) {
-    int text_width = 0;
-    char *e = vim_strchr(p, '\n');
-    if (e == NULL) {
-      ml_append_buf(buf, (*lnum)++, p, 0, false);
-      text_width = (int)mb_string2cells(p);
-      if (text_width > *max_width) {
-        *max_width = text_width;
-      }
-      break;
-    }
-    *e = NUL;
-    ml_append_buf(buf, (*lnum)++, p, (int)(e - p + 1), false);
-    inserted_bytes += (bcount_t)strlen(p) + 1;
-    text_width = (int)mb_string2cells(p);
-    if (text_width > *max_width) {
-      *max_width = text_width;
-    }
-    *e = '\n';
-    p = e + 1;
+  Error err = ERROR_INIT;
+  Arena arena = ARENA_EMPTY;
+  Array replacement = ARRAY_DICT_INIT;
+  char *token = NULL;
+  char *line = os_strtok(info, "\n", &token);
+  buf->b_p_ma = true;
+  while (line != NULL) {
+    ADD(replacement, STRING_OBJ(cstr_to_string(line)));
+    (*lnum)++;
+    (*max_width) = MAX(*max_width, (int)mb_string2cells(line));
+    line = os_strtok(NULL, "\n", &token);
   }
-  // delete the empty last line
-  ml_delete_buf(buf, buf->b_ml.ml_line_count, false);
-  if (get_cot_flags() & kOptCotFlagPopup) {
-    extmark_splice(buf, 1, 0, 1, 0, 0, buf->b_ml.ml_line_count, 0, inserted_bytes, kExtmarkNoUndo);
+
+  int original_textlock = textlock;
+  if (textlock > 0) {
+    textlock = 0;
+  }
+  nvim_buf_set_lines(0, buf->handle, 0, -1, false, replacement, &arena, &err);
+  textlock = original_textlock;
+  if (ERROR_SET(&err)) {
+    emsg(err.msg);
+    api_clear_error(&err);
   }
+  arena_mem_free(arena_finish(&arena));
+  api_free_array(replacement);
+  buf->b_p_ma = false;
 }
 
 /// adjust floating info preview window position
@@ -866,14 +873,6 @@ win_T *pum_set_info(int selected, char *info)
     if (!wp) {
       return NULL;
     }
-  } else {
-    // clean exist buffer
-    linenr_T count = wp->w_buffer->b_ml.ml_line_count;
-    while (!buf_is_empty(wp->w_buffer)) {
-      ml_delete_buf(wp->w_buffer, 1, false);
-    }
-    bcount_t deleted_bytes = get_region_bytecount(wp->w_buffer, 1, count, 0, 0);
-    extmark_splice(wp->w_buffer, 1, 0, count, 0, deleted_bytes, 1, 0, 0, kExtmarkNoUndo);
   }
   linenr_T lnum = 0;
   int max_info_width = 0;
@@ -1011,7 +1010,8 @@ static bool pum_set_selected(int n, int repeat)
             && (curbuf->b_nwindows == 1)
             && (curbuf->b_fname == NULL)
             && bt_nofile(curbuf)
-            && (curbuf->b_p_bh[0] == 'w')) {
+            && (curbuf->b_p_bh[0] == 'w')
+            && !use_float) {
           // Already a "wipeout" buffer, make it empty.
           while (!buf_is_empty(curbuf)) {
             ml_delete(1, false);
diff --git a/test/functional/ui/popupmenu_spec.lua b/test/functional/ui/popupmenu_spec.lua
index d1228d3607..60d59190ce 100644
--- a/test/functional/ui/popupmenu_spec.lua
+++ b/test/functional/ui/popupmenu_spec.lua
@@ -1680,7 +1680,7 @@ describe('builtin popupmenu', function()
       end)
     end
 
-    describe('floating window preview #popup', function()
+    describe('floating window preview popup', function()
       it('pum popup preview', function()
         --row must > 10
         screen:try_resize(40, 11)
@@ -1693,14 +1693,29 @@ describe('builtin popupmenu', function()
           endfunc
           set omnifunc=Omni_test
           set completeopt=menu,popup
-
           funct Set_info()
             let comp_info = complete_info()
             if comp_info['selected'] == 2
               call nvim__complete_set(comp_info['selected'], {"info": "3info"})
             endif
           endfunc
-          autocmd CompleteChanged * call Set_info()
+          funct TsHl()
+            let comp_info = complete_info()
+            if get(comp_info, 'previewbufnr', 0) > 0
+              call v:lua.vim.treesitter.start(comp_info['preview_bufnr'], 'markdown')
+            endif
+            if comp_info['selected'] == 0
+              call nvim__complete_set(comp_info['selected'], {"info": "```lua\nfunction test()\n  print('foo')\nend\n```"})
+            endif
+          endfunc
+          augroup Group
+            au!
+            autocmd CompleteChanged * :call Set_info()
+          augroup END
+          funct TestTs()
+            autocmd! Group
+            autocmd CompleteChanged * call TsHl()
+          endfunc
         ]])
         feed('Gi<C-x><C-o>')
         --floating preview in right
@@ -2004,6 +2019,90 @@ describe('builtin popupmenu', function()
           ]],
           }
         end
+        feed('<C-E><Esc>')
+
+        -- works when scroll with treesitter highlight
+        command('call TestTs()')
+        feed('S<C-x><C-o>')
+        if multigrid then
+          screen:expect({
+            grid = [[
+            ## grid 1
+              [2:----------------------------------------]|*10
+              [3:----------------------------------------]|
+            ## grid 2
+              one^                                     |
+              {1:~                                       }|*9
+            ## grid 3
+              {2:-- }{5:match 1 of 3}                         |
+            ## grid 5
+              {s:one                }|
+              {n:two                }|
+              {n:looooooooooooooong }|
+            ## grid 9
+              {n:```lua         }|
+              {n:function test()}|
+              {n:  print('foo') }|
+              {n:end            }|
+              {n:```            }|
+              {n:               }|
+            ]],
+            float_pos = {
+              [5] = { -1, 'NW', 2, 1, 0, false, 100 },
+              [9] = { 1005, 'NW', 1, 1, 19, false, 50 },
+            },
+            win_viewport = {
+              [2] = {
+                win = 1000,
+                topline = 0,
+                botline = 2,
+                curline = 0,
+                curcol = 3,
+                linecount = 1,
+                sum_scroll_delta = 0,
+              },
+              [9] = {
+                win = 1005,
+                topline = 0,
+                botline = 6,
+                curline = 0,
+                curcol = 0,
+                linecount = 5,
+                sum_scroll_delta = 0,
+              },
+            },
+            win_viewport_margins = {
+              [2] = {
+                bottom = 0,
+                left = 0,
+                right = 0,
+                top = 0,
+                win = 1000,
+              },
+              [9] = {
+                bottom = 0,
+                left = 0,
+                right = 0,
+                top = 0,
+                win = 1005,
+              },
+            },
+          })
+        else
+          screen:expect({
+            grid = [[
+              one^                                     |
+              {s:one                }{n:```lua         }{1:      }|
+              {n:two                function test()}{1:      }|
+              {n:looooooooooooooong   print('foo') }{1:      }|
+              {1:~                  }{n:end            }{1:      }|
+              {1:~                  }{n:```            }{1:      }|
+              {1:~                  }{n:               }{1:      }|
+              {1:~                                       }|*3
+              {2:-- }{5:match 1 of 3}                         |
+            ]],
+          })
+        end
       end)
     end)