Merge pull request #12968 from erw7/fix-substitute2

fix substitute problem with inccommand

src/nvim/api/buffer.c

@@ -1420,7 +1420,7 @@ Integer nvim_buf_set_extmark(Buffer buffer, Integer ns_id,
   }
 
   id = extmark_set(buf, (uint64_t)ns_id, id,
-                   (int)line, (colnr_T)col, line2, col2, decor, kExtmarkUndo);
+                   (int)line, (colnr_T)col, line2, col2, decor, kExtmarkNoUndo);
 
   return (Integer)id;
 
@@ -1534,7 +1534,7 @@ Integer nvim_buf_add_highlight(Buffer buffer,
   ns_id = extmark_set(buf, ns_id, 0,
                       (int)line, (colnr_T)col_start,
                       end_line, (colnr_T)col_end,
-                      decoration_hl(hl_id), kExtmarkUndo);
+                      decoration_hl(hl_id), kExtmarkNoUndo);
   return src_id;
 }
 
@@ -1664,7 +1664,7 @@ Integer nvim_buf_set_virtual_text(Buffer buffer,
   Decoration *decor = xcalloc(1, sizeof(*decor));
   decor->virt_text = virt_text;
 
-  extmark_set(buf, ns_id, 0, (int)line, 0, -1, -1, decor, kExtmarkUndo);
+  extmark_set(buf, ns_id, 0, (int)line, 0, -1, -1, decor, kExtmarkNoUndo);
   return src_id;
 }
 

src/nvim/extmark.c

@@ -783,7 +783,7 @@ void bufhl_add_hl_pos_offset(buf_T *buf,
     }
     (void)extmark_set(buf, (uint64_t)src_id, 0,
                       (int)lnum-1, hl_start, (int)lnum-1+end_off, hl_end,
-                      decor, kExtmarkUndo);
+                      decor, kExtmarkNoUndo);
   }
 }
 

src/nvim/undo.c

@@ -3029,8 +3029,6 @@ u_header_T *u_force_get_undo_header(buf_T *buf)
     curbuf = buf;
     // Args are tricky: this means replace empty range by empty range..
     u_savecommon(0, 1, 1, true);
-    curbuf = save_curbuf;
-
     uhp = buf->b_u_curhead;
     if (!uhp) {
       uhp = buf->b_u_newhead;
@@ -3038,6 +3036,7 @@ u_header_T *u_force_get_undo_header(buf_T *buf)
         abort();
       }
     }
+    curbuf = save_curbuf;
   }
   return uhp;
 }

test/functional/api/highlight_spec.lua

@@ -7,6 +7,7 @@ local meths = helpers.meths
 local funcs = helpers.funcs
 local pcall_err = helpers.pcall_err
 local ok = helpers.ok
+local assert_alive = helpers.assert_alive
 
 describe('API: highlight',function()
   local expected_rgb = {
@@ -145,4 +146,15 @@ describe('API: highlight',function()
     eq({foreground=tonumber("0x888888"), background=tonumber("0x888888")},
        meths.get_hl_by_name("Shrubbery", true))
   end)
+
+  it("nvim_buf_add_highlight to other buffer doesn't crash if undo is disabled #12873", function()
+    command('vsplit file')
+    local err, _ = pcall(meths.buf_set_option, 1, 'undofile', false)
+    eq(true, err)
+    err, _ = pcall(meths.buf_set_option, 1, 'undolevels', -1)
+    eq(true, err)
+    err, _ = pcall(meths.buf_add_highlight, 1, -1, 'Question', 0, 0, -1)
+    eq(true, err)
+    assert_alive()
+  end)
 end)

test/functional/ui/inccommand_spec.lua

@@ -2750,6 +2750,26 @@ it(':substitute with inccommand, timer-induced :redraw #9777', function()
   ]])
 end)
 
+it(":substitute doesn't crash with inccommand, if undo is empty #12932", function()
+  local screen = Screen.new(10,5)
+  clear()
+  command('set undolevels=-1')
+  common_setup(screen, 'split', 'test')
+  feed(':%s/test')
+  sleep(100)
+  feed('/')
+  sleep(100)
+  feed('f')
+  screen:expect([[
+  {12:f}           |
+  {15:~           }|
+  {15:~           }|
+  {15:~           }|
+  :%s/test/f^  |
+  ]])
+  assert_alive()
+end)
+
 it('long :%s/ with inccommand does not collapse cmdline', function()
   local screen = Screen.new(10,5)
   clear()