vim-patch:8.2.4638: superfluous check if a redraw is needed for 'cursorline'

Problem:    Superfluous check if a redraw is needed for 'cursorline'.
Solution:   Remove check_redraw_cursorline(). (closes vim/vim#10030, closes vim/vim#10029)
https://github.com/vim/vim/commit/3e559cd88486ffab6b6fb4e0921b4600d137a617

redraw_after_callback() is N/A.
Omits changes that just revert code from patch 8.2.4630.

6 files changed, 152 insertions, 26 deletions

diff --git a/src/nvim/move.c b/src/nvim/move.c
index 751e0046bc..9b35a7da0a 100644
--- a/src/nvim/move.c
+++ b/src/nvim/move.c
@@ -95,7 +95,7 @@ static void comp_botline(win_T *wp)
   win_check_anchored_floats(wp);
 }
 
-// Redraw when w_cline_row changes and 'relativenumber' or 'cursorline' is set.
+/// Redraw when w_cline_row changes and 'relativenumber' or 'cursorline' is set.
 void redraw_for_cursorline(win_T *wp)
   FUNC_ATTR_NONNULL_ALL
 {
@@ -107,6 +107,22 @@ void redraw_for_cursorline(win_T *wp)
   }
 }
 
+/// Redraw when w_virtcol changes and 'cursorcolumn' is set or 'cursorlineopt'
+/// contains "screenline".
+static void redraw_for_cursorcolumn(win_T *wp)
+  FUNC_ATTR_NONNULL_ALL
+{
+  if ((wp->w_valid & VALID_VIRTCOL) == 0 && !pum_visible()) {
+    if (wp->w_p_cuc) {
+      // When 'cursorcolumn' is set need to redraw with SOME_VALID.
+      redraw_later(wp, SOME_VALID);
+    } else if (wp->w_p_cul && (wp->w_p_culopt_flags & CULOPT_SCRLINE)) {
+      // When 'cursorlineopt' contains "screenline" need to redraw with VALID.
+      redraw_later(wp, VALID);
+    }
+  }
+}
+
 /*
  * Update curwin->w_topline and redraw if necessary.
  * Used to update the screen before printing a message.
@@ -623,11 +639,8 @@ void validate_virtcol_win(win_T *wp)
   check_cursor_moved(wp);
   if (!(wp->w_valid & VALID_VIRTCOL)) {
     getvvcol(wp, &wp->w_cursor, NULL, &(wp->w_virtcol), NULL);
+    redraw_for_cursorcolumn(wp);
     wp->w_valid |= VALID_VIRTCOL;
-    if (wp->w_p_cuc
-        && !pum_visible()) {
-      redraw_later(wp, SOME_VALID);
-    }
   }
 }
 
@@ -930,11 +943,7 @@ void curs_columns(win_T *wp, int may_scroll)
     redraw_later(wp, NOT_VALID);
   }
 
-  // Redraw when w_virtcol changes and 'cursorcolumn' is set
-  if (wp->w_p_cuc && (wp->w_valid & VALID_VIRTCOL) == 0
-      && !pum_visible()) {
-    redraw_later(wp, SOME_VALID);
-  }
+  redraw_for_cursorcolumn(curwin);
 
   // now w_leftcol is valid, avoid check_cursor_moved() thinking otherwise
   wp->w_valid_leftcol = wp->w_leftcol;
diff --git a/src/nvim/normal.c b/src/nvim/normal.c
index e773351d63..6c7595d1a4 100644
--- a/src/nvim/normal.c
+++ b/src/nvim/normal.c
@@ -1295,9 +1295,6 @@ static void normal_redraw(NormalState *s)
     redrawWinline(curwin, curwin->w_cursor.lnum);
   }
 
-  // Might need to update for 'cursorline'.
-  check_redraw_cursorline();
-
   if (VIsual_active) {
     update_curbuf(INVERTED);  // update inverted part
   } else if (must_redraw) {
diff --git a/src/nvim/screen.c b/src/nvim/screen.c
index 41a129dba9..67eee55c51 100644
--- a/src/nvim/screen.c
+++ b/src/nvim/screen.c
@@ -7617,16 +7617,3 @@ win_T *get_win_by_grid_handle(handle_T handle)
   }
   return NULL;
 }
-
-/// Check if the cursor moved and 'cursorline' is set.  Mark for a VALID redraw
-/// if needed.
-void check_redraw_cursorline(void)
-{
-  // When 'cursorlineopt' is "screenline" need to redraw always.
-  if (curwin->w_p_cul
-      && (curwin->w_last_cursorline != curwin->w_cursor.lnum
-          || (curwin->w_p_culopt_flags & CULOPT_SCRLINE))
-      && !char_avail()) {
-    redraw_later(curwin, VALID);
-  }
-}
diff --git a/src/nvim/testdir/test_highlight.vim b/src/nvim/testdir/test_highlight.vim
index aa7b3a225b..6387ec62af 100644
--- a/src/nvim/testdir/test_highlight.vim
+++ b/src/nvim/testdir/test_highlight.vim
@@ -597,6 +597,31 @@ func Test_cursorline_with_visualmode()
   call delete('Xtest_cursorline_with_visualmode')
 endfunc
 
+func Test_cursorcolumn_callback()
+  CheckScreendump
+  CheckFeature timers
+
+  let lines =<< trim END
+      call setline(1, ['aaaaa', 'bbbbb', 'ccccc', 'ddddd'])
+      set cursorcolumn
+      call cursor(4, 5)
+
+      func Func(timer)
+        call cursor(1, 1)
+      endfunc
+
+      call timer_start(300, 'Func')
+  END
+  call writefile(lines, 'Xcuc_timer')
+
+  let buf = RunVimInTerminal('-S Xcuc_timer', #{rows: 8})
+  call TermWait(buf, 310)
+  call VerifyScreenDump(buf, 'Test_cursorcolumn_callback_1', {})
+
+  call StopVimInTerminal(buf)
+  call delete('Xcuc_timer')
+endfunc
+
 func Test_colorcolumn()
   CheckScreendump
 
diff --git a/src/nvim/testdir/test_number.vim b/src/nvim/testdir/test_number.vim
index dfbdc0bffd..521b0cf706 100644
--- a/src/nvim/testdir/test_number.vim
+++ b/src/nvim/testdir/test_number.vim
@@ -298,6 +298,31 @@ func Test_relativenumber_colors()
   call delete('XTest_relnr')
 endfunc
 
+func Test_relativenumber_callback()
+  CheckScreendump
+  CheckFeature timers
+
+  let lines =<< trim END
+      call setline(1, ['aaaaa', 'bbbbb', 'ccccc', 'ddddd'])
+      set relativenumber
+      call cursor(4, 1)
+
+      func Func(timer)
+        call cursor(1, 1)
+      endfunc
+
+      call timer_start(300, 'Func')
+  END
+  call writefile(lines, 'Xrnu_timer')
+
+  let buf = RunVimInTerminal('-S Xrnu_timer', #{rows: 8})
+  call TermWait(buf, 310)
+  call VerifyScreenDump(buf, 'Test_relativenumber_callback_1', {})
+
+  call StopVimInTerminal(buf)
+  call delete('Xrnu_timer')
+endfunc
+
 " Test for displaying line numbers with 'rightleft'
 func Test_number_rightleft()
   CheckFeature rightleft
diff --git a/test/functional/ui/highlight_spec.lua b/test/functional/ui/highlight_spec.lua
index 559738ddab..2053901857 100644
--- a/test/functional/ui/highlight_spec.lua
+++ b/test/functional/ui/highlight_spec.lua
@@ -1266,6 +1266,49 @@ describe('CursorLine and CursorLineNr highlights', function()
   end)
 end)
 
+describe('CursorColumn highlight', function()
+  before_each(clear)
+  it('is updated if cursor is moved from timer', function()
+    local screen = Screen.new(50, 8)
+    screen:set_default_attr_ids({
+      [1] = {background = Screen.colors.Gray90},  -- CursorColumn
+      [2] = {bold = true, foreground = Screen.colors.Blue1},  -- NonText
+    })
+    screen:attach()
+    exec([[
+      call setline(1, ['aaaaa', 'bbbbb', 'ccccc', 'ddddd'])
+      set cursorcolumn
+      call cursor(4, 5)
+
+      func Func(timer)
+        call cursor(1, 1)
+      endfunc
+
+      call timer_start(300, 'Func')
+    ]])
+    screen:expect({grid = [[
+      aaaa{1:a}                                             |
+      bbbb{1:b}                                             |
+      cccc{1:c}                                             |
+      dddd^d                                             |
+      {2:~                                                 }|
+      {2:~                                                 }|
+      {2:~                                                 }|
+                                                        |
+    ]], timeout = 100})
+    screen:expect({grid = [[
+      ^aaaaa                                             |
+      {1:b}bbbb                                             |
+      {1:c}cccc                                             |
+      {1:d}dddd                                             |
+      {2:~                                                 }|
+      {2:~                                                 }|
+      {2:~                                                 }|
+                                                        |
+    ]]})
+  end)
+end)
+
 describe('ColorColumn highlight', function()
   local screen
 
@@ -1570,6 +1613,46 @@ describe("'number' and 'relativenumber' highlight", function()
                           |
     ]])
   end)
+
+  it('relative number highlight is updated if cursor is moved from timer', function()
+    local screen = Screen.new(50, 8)
+    screen:set_default_attr_ids({
+      [1] = {foreground = Screen.colors.Brown},  -- LineNr
+      [2] = {bold = true, foreground = Screen.colors.Blue1},  -- NonText
+    })
+    screen:attach()
+    exec([[
+      call setline(1, ['aaaaa', 'bbbbb', 'ccccc', 'ddddd'])
+      set relativenumber
+      call cursor(4, 1)
+
+      func Func(timer)
+        call cursor(1, 1)
+      endfunc
+
+      call timer_start(300, 'Func')
+    ]])
+    screen:expect({grid = [[
+      {1:  3 }aaaaa                                         |
+      {1:  2 }bbbbb                                         |
+      {1:  1 }ccccc                                         |
+      {1:  0 }^ddddd                                         |
+      {2:~                                                 }|
+      {2:~                                                 }|
+      {2:~                                                 }|
+                                                        |
+    ]], timeout = 100})
+    screen:expect({grid = [[
+      {1:  0 }^aaaaa                                         |
+      {1:  1 }bbbbb                                         |
+      {1:  2 }ccccc                                         |
+      {1:  3 }ddddd                                         |
+      {2:~                                                 }|
+      {2:~                                                 }|
+      {2:~                                                 }|
+                                                        |
+    ]]})
+  end)
 end)
 
 describe("'winhighlight' highlight", function()