vim-patch:9.1.0083: Redrawing can be improved when deleting lines with 'number'

Problem:  Redrawing can be improved when inserting/deleting lines with 'number'.
Solution: Only redraw the number column of lines below changed lines.
          Add a test as this wasn't previously tested.
          (zeertzjq)

closes: vim/vim#13985

https://github.com/vim/vim/commit/ae07ebc04b0726e12b1af39d52e01d86ae79ef0a

4 files changed, 340 insertions, 263 deletions

diff --git a/src/nvim/drawscreen.c b/src/nvim/drawscreen.c
index f23c0a0fd3..3d048d178e 100644
--- a/src/nvim/drawscreen.c
+++ b/src/nvim/drawscreen.c
@@ -1643,12 +1643,6 @@ static void win_update(win_T *wp)
         top_end = 1;
       }
     }
-
-    // When line numbers are displayed need to redraw all lines below
-    // inserted/deleted lines.
-    if (mod_top != 0 && buf->b_mod_xlines != 0 && wp->w_p_nu) {
-      mod_bot = MAXLNUM;
-    }
   }
 
   wp->w_redraw_top = 0;  // reset for next time
@@ -2326,9 +2320,12 @@ static void win_update(win_T *wp)
       idx++;
       lnum += foldinfo.fi_lines + 1;
     } else {
-      if (wp->w_p_rnu && wp->w_last_cursor_lnum_rnu != wp->w_cursor.lnum) {
-        // 'relativenumber' set and cursor moved vertically: The
-        // text doesn't need to be drawn, but the number column does.
+      // If:
+      // - 'number' is set and below inserted/deleted lines, or
+      // - 'relativenumber' is set and cursor moved vertically,
+      // the text doesn't need to be redrawn, but the number column does.
+      if ((wp->w_p_nu && mod_top != 0 && lnum >= mod_bot && buf->b_mod_xlines != 0)
+          || (wp->w_p_rnu && wp->w_last_cursor_lnum_rnu != wp->w_cursor.lnum)) {
         foldinfo_T info = wp->w_p_cul && lnum == wp->w_cursor.lnum
                           ? cursorline_fi : fold_info(wp, lnum);
         win_line(wp, lnum, srow, wp->w_grid.rows, wp->w_lines[idx].wl_size, &spv, info);
diff --git a/test/functional/legacy/number_spec.lua b/test/functional/legacy/number_spec.lua
new file mode 100644
index 0000000000..c112532eed
--- /dev/null
+++ b/test/functional/legacy/number_spec.lua
@@ -0,0 +1,306 @@
+local helpers = require('test.functional.helpers')(after_each)
+local Screen = require('test.functional.ui.screen')
+local clear = helpers.clear
+local command = helpers.command
+local exec = helpers.exec
+local feed = helpers.feed
+
+describe("'number' and 'relativenumber'", function()
+  before_each(clear)
+
+  -- oldtest: Test_relativenumber_colors()
+  it('LineNr, LineNrAbove and LineNrBelow', function()
+    local screen = Screen.new(50, 10)
+    screen:set_default_attr_ids({
+      [1] = { foreground = Screen.colors.Red },
+      [2] = { foreground = Screen.colors.Blue },
+      [3] = { foreground = Screen.colors.Green },
+    })
+    screen:attach()
+    exec([[
+      call setline(1, range(200))
+      111
+      set number relativenumber
+      hi LineNr guifg=red
+    ]])
+    screen:expect([[
+      {1:  4 }106                                           |
+      {1:  3 }107                                           |
+      {1:  2 }108                                           |
+      {1:  1 }109                                           |
+      {1:111 }^110                                           |
+      {1:  1 }111                                           |
+      {1:  2 }112                                           |
+      {1:  3 }113                                           |
+      {1:  4 }114                                           |
+                                                        |
+    ]])
+    command('hi LineNrAbove guifg=blue')
+    screen:expect([[
+      {2:  4 }106                                           |
+      {2:  3 }107                                           |
+      {2:  2 }108                                           |
+      {2:  1 }109                                           |
+      {1:111 }^110                                           |
+      {1:  1 }111                                           |
+      {1:  2 }112                                           |
+      {1:  3 }113                                           |
+      {1:  4 }114                                           |
+                                                        |
+    ]])
+    command('hi LineNrBelow guifg=green')
+    screen:expect([[
+      {2:  4 }106                                           |
+      {2:  3 }107                                           |
+      {2:  2 }108                                           |
+      {2:  1 }109                                           |
+      {1:111 }^110                                           |
+      {3:  1 }111                                           |
+      {3:  2 }112                                           |
+      {3:  3 }113                                           |
+      {3:  4 }114                                           |
+                                                        |
+    ]])
+    command('hi clear LineNrAbove')
+    screen:expect([[
+      {1:  4 }106                                           |
+      {1:  3 }107                                           |
+      {1:  2 }108                                           |
+      {1:  1 }109                                           |
+      {1:111 }^110                                           |
+      {3:  1 }111                                           |
+      {3:  2 }112                                           |
+      {3:  3 }113                                           |
+      {3:  4 }114                                           |
+                                                        |
+    ]])
+  end)
+
+  -- oldtest: Test_relativenumber_colors_wrapped()
+  it('LineNr, LineNrAbove and LineNrBelow with wrapped lines', function()
+    local screen = Screen.new(50, 20)
+    screen:set_default_attr_ids({
+      [1] = { background = Screen.colors.Red, foreground = Screen.colors.Black },
+      [2] = { background = Screen.colors.Blue, foreground = Screen.colors.Black },
+      [3] = { background = Screen.colors.Green, foreground = Screen.colors.Black },
+      [4] = { bold = true, foreground = Screen.colors.Blue },
+    })
+    screen:attach()
+    exec([[
+      set display=lastline scrolloff=0
+      call setline(1, range(200)->map('v:val->string()->repeat(40)'))
+      111
+      set number relativenumber
+      hi LineNr guibg=red guifg=black
+      hi LineNrAbove guibg=blue guifg=black
+      hi LineNrBelow guibg=green guifg=black
+    ]])
+    screen:expect([[
+      {2:  2 }1081081081081081081081081081081081081081081081|
+      {2:    }0810810810810810810810810810810810810810810810|
+      {2:    }8108108108108108108108108108                  |
+      {2:  1 }1091091091091091091091091091091091091091091091|
+      {2:    }0910910910910910910910910910910910910910910910|
+      {2:    }9109109109109109109109109109                  |
+      {1:111 }^1101101101101101101101101101101101101101101101|
+      {1:    }1011011011011011011011011011011011011011011011|
+      {1:    }0110110110110110110110110110                  |
+      {3:  1 }1111111111111111111111111111111111111111111111|
+      {3:    }1111111111111111111111111111111111111111111111|
+      {3:    }1111111111111111111111111111                  |
+      {3:  2 }1121121121121121121121121121121121121121121121|
+      {3:    }1211211211211211211211211211211211211211211211|
+      {3:    }2112112112112112112112112112                  |
+      {3:  3 }1131131131131131131131131131131131131131131131|
+      {3:    }1311311311311311311311311311311311311311311311|
+      {3:    }3113113113113113113113113113                  |
+      {3:  4 }1141141141141141141141141141141141141141141{4:@@@}|
+                                                        |
+    ]])
+    feed('k')
+    screen:expect([[
+      {2:  1 }1081081081081081081081081081081081081081081081|
+      {2:    }0810810810810810810810810810810810810810810810|
+      {2:    }8108108108108108108108108108                  |
+      {1:110 }^1091091091091091091091091091091091091091091091|
+      {1:    }0910910910910910910910910910910910910910910910|
+      {1:    }9109109109109109109109109109                  |
+      {3:  1 }1101101101101101101101101101101101101101101101|
+      {3:    }1011011011011011011011011011011011011011011011|
+      {3:    }0110110110110110110110110110                  |
+      {3:  2 }1111111111111111111111111111111111111111111111|
+      {3:    }1111111111111111111111111111111111111111111111|
+      {3:    }1111111111111111111111111111                  |
+      {3:  3 }1121121121121121121121121121121121121121121121|
+      {3:    }1211211211211211211211211211211211211211211211|
+      {3:    }2112112112112112112112112112                  |
+      {3:  4 }1131131131131131131131131131131131131131131131|
+      {3:    }1311311311311311311311311311311311311311311311|
+      {3:    }3113113113113113113113113113                  |
+      {3:  5 }1141141141141141141141141141141141141141141{4:@@@}|
+                                                        |
+    ]])
+    feed('2j')
+    screen:expect([[
+      {2:  3 }1081081081081081081081081081081081081081081081|
+      {2:    }0810810810810810810810810810810810810810810810|
+      {2:    }8108108108108108108108108108                  |
+      {2:  2 }1091091091091091091091091091091091091091091091|
+      {2:    }0910910910910910910910910910910910910910910910|
+      {2:    }9109109109109109109109109109                  |
+      {2:  1 }1101101101101101101101101101101101101101101101|
+      {2:    }1011011011011011011011011011011011011011011011|
+      {2:    }0110110110110110110110110110                  |
+      {1:112 }^1111111111111111111111111111111111111111111111|
+      {1:    }1111111111111111111111111111111111111111111111|
+      {1:    }1111111111111111111111111111                  |
+      {3:  1 }1121121121121121121121121121121121121121121121|
+      {3:    }1211211211211211211211211211211211211211211211|
+      {3:    }2112112112112112112112112112                  |
+      {3:  2 }1131131131131131131131131131131131131131131131|
+      {3:    }1311311311311311311311311311311311311311311311|
+      {3:    }3113113113113113113113113113                  |
+      {3:  3 }1141141141141141141141141141141141141141141{4:@@@}|
+                                                        |
+    ]])
+    feed('2j')
+    screen:expect([[
+      {2:  5 }1081081081081081081081081081081081081081081081|
+      {2:    }0810810810810810810810810810810810810810810810|
+      {2:    }8108108108108108108108108108                  |
+      {2:  4 }1091091091091091091091091091091091091091091091|
+      {2:    }0910910910910910910910910910910910910910910910|
+      {2:    }9109109109109109109109109109                  |
+      {2:  3 }1101101101101101101101101101101101101101101101|
+      {2:    }1011011011011011011011011011011011011011011011|
+      {2:    }0110110110110110110110110110                  |
+      {2:  2 }1111111111111111111111111111111111111111111111|
+      {2:    }1111111111111111111111111111111111111111111111|
+      {2:    }1111111111111111111111111111                  |
+      {2:  1 }1121121121121121121121121121121121121121121121|
+      {2:    }1211211211211211211211211211211211211211211211|
+      {2:    }2112112112112112112112112112                  |
+      {1:114 }^1131131131131131131131131131131131131131131131|
+      {1:    }1311311311311311311311311311311311311311311311|
+      {1:    }3113113113113113113113113113                  |
+      {3:  1 }1141141141141141141141141141141141141141141{4:@@@}|
+                                                        |
+    ]])
+    feed('k')
+    screen:expect([[
+      {2:  4 }1081081081081081081081081081081081081081081081|
+      {2:    }0810810810810810810810810810810810810810810810|
+      {2:    }8108108108108108108108108108                  |
+      {2:  3 }1091091091091091091091091091091091091091091091|
+      {2:    }0910910910910910910910910910910910910910910910|
+      {2:    }9109109109109109109109109109                  |
+      {2:  2 }1101101101101101101101101101101101101101101101|
+      {2:    }1011011011011011011011011011011011011011011011|
+      {2:    }0110110110110110110110110110                  |
+      {2:  1 }1111111111111111111111111111111111111111111111|
+      {2:    }1111111111111111111111111111111111111111111111|
+      {2:    }1111111111111111111111111111                  |
+      {1:113 }^1121121121121121121121121121121121121121121121|
+      {1:    }1211211211211211211211211211211211211211211211|
+      {1:    }2112112112112112112112112112                  |
+      {3:  1 }1131131131131131131131131131131131131131131131|
+      {3:    }1311311311311311311311311311311311311311311311|
+      {3:    }3113113113113113113113113113                  |
+      {3:  2 }1141141141141141141141141141141141141141141{4:@@@}|
+                                                        |
+    ]])
+  end)
+
+  -- oldtest: Test_relativenumber_callback()
+  it('relative line numbers are 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:~                                                 }|*3
+                                                        |
+    ]],
+      timeout = 100,
+    })
+    screen:expect({
+      grid = [[
+      {1:  0 }^aaaaa                                         |
+      {1:  1 }bbbbb                                         |
+      {1:  2 }ccccc                                         |
+      {1:  3 }ddddd                                         |
+      {2:~                                                 }|*3
+                                                        |
+    ]],
+    })
+  end)
+
+  -- oldtest: Test_number_insert_delete_lines()
+  it('line numbers are updated when deleting/inserting lines', 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, range(1, 7))
+      set number
+      call cursor(2, 1)
+    ]])
+    local snapshot1 = [[
+      {1:  1 }1                                             |
+      {1:  2 }^2                                             |
+      {1:  3 }3                                             |
+      {1:  4 }4                                             |
+      {1:  5 }5                                             |
+      {1:  6 }6                                             |
+      {1:  7 }7                                             |
+                                                        |
+    ]]
+    screen:expect(snapshot1)
+    feed('dd')
+    screen:expect([[
+      {1:  1 }1                                             |
+      {1:  2 }^3                                             |
+      {1:  3 }4                                             |
+      {1:  4 }5                                             |
+      {1:  5 }6                                             |
+      {1:  6 }7                                             |
+      {2:~                                                 }|
+                                                        |
+    ]])
+    feed('P')
+    screen:expect(snapshot1)
+    feed('2dd')
+    screen:expect([[
+      {1:  1 }1                                             |
+      {1:  2 }^4                                             |
+      {1:  3 }5                                             |
+      {1:  4 }6                                             |
+      {1:  5 }7                                             |
+      {2:~                                                 }|*2
+                                                        |
+    ]])
+    feed('P')
+    screen:expect(snapshot1)
+  end)
+end)
diff --git a/test/functional/ui/highlight_spec.lua b/test/functional/ui/highlight_spec.lua
index d9bb4d3a98..d2320db2a1 100644
--- a/test/functional/ui/highlight_spec.lua
+++ b/test/functional/ui/highlight_spec.lua
@@ -1705,255 +1705,6 @@ describe('MsgSeparator highlight and msgsep fillchar', function()
   end)
 end)
 
-describe("'number' and 'relativenumber' highlight", function()
-  before_each(clear)
-
-  -- oldtest: Test_relativenumber_colors()
-  it('LineNr, LineNrAbove and LineNrBelow', function()
-    local screen = Screen.new(50, 10)
-    screen:set_default_attr_ids({
-      [1] = { foreground = Screen.colors.Red },
-      [2] = { foreground = Screen.colors.Blue },
-      [3] = { foreground = Screen.colors.Green },
-    })
-    screen:attach()
-    exec([[
-      call setline(1, range(200))
-      111
-      set number relativenumber
-      hi LineNr guifg=red
-    ]])
-    screen:expect([[
-      {1:  4 }106                                           |
-      {1:  3 }107                                           |
-      {1:  2 }108                                           |
-      {1:  1 }109                                           |
-      {1:111 }^110                                           |
-      {1:  1 }111                                           |
-      {1:  2 }112                                           |
-      {1:  3 }113                                           |
-      {1:  4 }114                                           |
-                                                        |
-    ]])
-    command('hi LineNrAbove guifg=blue')
-    screen:expect([[
-      {2:  4 }106                                           |
-      {2:  3 }107                                           |
-      {2:  2 }108                                           |
-      {2:  1 }109                                           |
-      {1:111 }^110                                           |
-      {1:  1 }111                                           |
-      {1:  2 }112                                           |
-      {1:  3 }113                                           |
-      {1:  4 }114                                           |
-                                                        |
-    ]])
-    command('hi LineNrBelow guifg=green')
-    screen:expect([[
-      {2:  4 }106                                           |
-      {2:  3 }107                                           |
-      {2:  2 }108                                           |
-      {2:  1 }109                                           |
-      {1:111 }^110                                           |
-      {3:  1 }111                                           |
-      {3:  2 }112                                           |
-      {3:  3 }113                                           |
-      {3:  4 }114                                           |
-                                                        |
-    ]])
-    command('hi clear LineNrAbove')
-    screen:expect([[
-      {1:  4 }106                                           |
-      {1:  3 }107                                           |
-      {1:  2 }108                                           |
-      {1:  1 }109                                           |
-      {1:111 }^110                                           |
-      {3:  1 }111                                           |
-      {3:  2 }112                                           |
-      {3:  3 }113                                           |
-      {3:  4 }114                                           |
-                                                        |
-    ]])
-  end)
-
-  -- oldtest: Test_relativenumber_colors_wrapped()
-  it('LineNr, LineNrAbove and LineNrBelow with wrapped lines', function()
-    local screen = Screen.new(50, 20)
-    screen:set_default_attr_ids({
-      [1] = { background = Screen.colors.Red, foreground = Screen.colors.Black },
-      [2] = { background = Screen.colors.Blue, foreground = Screen.colors.Black },
-      [3] = { background = Screen.colors.Green, foreground = Screen.colors.Black },
-      [4] = { bold = true, foreground = Screen.colors.Blue },
-    })
-    screen:attach()
-    exec([[
-      set display=lastline scrolloff=0
-      call setline(1, range(200)->map('v:val->string()->repeat(40)'))
-      111
-      set number relativenumber
-      hi LineNr guibg=red guifg=black
-      hi LineNrAbove guibg=blue guifg=black
-      hi LineNrBelow guibg=green guifg=black
-    ]])
-    screen:expect([[
-      {2:  2 }1081081081081081081081081081081081081081081081|
-      {2:    }0810810810810810810810810810810810810810810810|
-      {2:    }8108108108108108108108108108                  |
-      {2:  1 }1091091091091091091091091091091091091091091091|
-      {2:    }0910910910910910910910910910910910910910910910|
-      {2:    }9109109109109109109109109109                  |
-      {1:111 }^1101101101101101101101101101101101101101101101|
-      {1:    }1011011011011011011011011011011011011011011011|
-      {1:    }0110110110110110110110110110                  |
-      {3:  1 }1111111111111111111111111111111111111111111111|
-      {3:    }1111111111111111111111111111111111111111111111|
-      {3:    }1111111111111111111111111111                  |
-      {3:  2 }1121121121121121121121121121121121121121121121|
-      {3:    }1211211211211211211211211211211211211211211211|
-      {3:    }2112112112112112112112112112                  |
-      {3:  3 }1131131131131131131131131131131131131131131131|
-      {3:    }1311311311311311311311311311311311311311311311|
-      {3:    }3113113113113113113113113113                  |
-      {3:  4 }1141141141141141141141141141141141141141141{4:@@@}|
-                                                        |
-    ]])
-    feed('k')
-    screen:expect([[
-      {2:  1 }1081081081081081081081081081081081081081081081|
-      {2:    }0810810810810810810810810810810810810810810810|
-      {2:    }8108108108108108108108108108                  |
-      {1:110 }^1091091091091091091091091091091091091091091091|
-      {1:    }0910910910910910910910910910910910910910910910|
-      {1:    }9109109109109109109109109109                  |
-      {3:  1 }1101101101101101101101101101101101101101101101|
-      {3:    }1011011011011011011011011011011011011011011011|
-      {3:    }0110110110110110110110110110                  |
-      {3:  2 }1111111111111111111111111111111111111111111111|
-      {3:    }1111111111111111111111111111111111111111111111|
-      {3:    }1111111111111111111111111111                  |
-      {3:  3 }1121121121121121121121121121121121121121121121|
-      {3:    }1211211211211211211211211211211211211211211211|
-      {3:    }2112112112112112112112112112                  |
-      {3:  4 }1131131131131131131131131131131131131131131131|
-      {3:    }1311311311311311311311311311311311311311311311|
-      {3:    }3113113113113113113113113113                  |
-      {3:  5 }1141141141141141141141141141141141141141141{4:@@@}|
-                                                        |
-    ]])
-    feed('2j')
-    screen:expect([[
-      {2:  3 }1081081081081081081081081081081081081081081081|
-      {2:    }0810810810810810810810810810810810810810810810|
-      {2:    }8108108108108108108108108108                  |
-      {2:  2 }1091091091091091091091091091091091091091091091|
-      {2:    }0910910910910910910910910910910910910910910910|
-      {2:    }9109109109109109109109109109                  |
-      {2:  1 }1101101101101101101101101101101101101101101101|
-      {2:    }1011011011011011011011011011011011011011011011|
-      {2:    }0110110110110110110110110110                  |
-      {1:112 }^1111111111111111111111111111111111111111111111|
-      {1:    }1111111111111111111111111111111111111111111111|
-      {1:    }1111111111111111111111111111                  |
-      {3:  1 }1121121121121121121121121121121121121121121121|
-      {3:    }1211211211211211211211211211211211211211211211|
-      {3:    }2112112112112112112112112112                  |
-      {3:  2 }1131131131131131131131131131131131131131131131|
-      {3:    }1311311311311311311311311311311311311311311311|
-      {3:    }3113113113113113113113113113                  |
-      {3:  3 }1141141141141141141141141141141141141141141{4:@@@}|
-                                                        |
-    ]])
-    feed('2j')
-    screen:expect([[
-      {2:  5 }1081081081081081081081081081081081081081081081|
-      {2:    }0810810810810810810810810810810810810810810810|
-      {2:    }8108108108108108108108108108                  |
-      {2:  4 }1091091091091091091091091091091091091091091091|
-      {2:    }0910910910910910910910910910910910910910910910|
-      {2:    }9109109109109109109109109109                  |
-      {2:  3 }1101101101101101101101101101101101101101101101|
-      {2:    }1011011011011011011011011011011011011011011011|
-      {2:    }0110110110110110110110110110                  |
-      {2:  2 }1111111111111111111111111111111111111111111111|
-      {2:    }1111111111111111111111111111111111111111111111|
-      {2:    }1111111111111111111111111111                  |
-      {2:  1 }1121121121121121121121121121121121121121121121|
-      {2:    }1211211211211211211211211211211211211211211211|
-      {2:    }2112112112112112112112112112                  |
-      {1:114 }^1131131131131131131131131131131131131131131131|
-      {1:    }1311311311311311311311311311311311311311311311|
-      {1:    }3113113113113113113113113113                  |
-      {3:  1 }1141141141141141141141141141141141141141141{4:@@@}|
-                                                        |
-    ]])
-    feed('k')
-    screen:expect([[
-      {2:  4 }1081081081081081081081081081081081081081081081|
-      {2:    }0810810810810810810810810810810810810810810810|
-      {2:    }8108108108108108108108108108                  |
-      {2:  3 }1091091091091091091091091091091091091091091091|
-      {2:    }0910910910910910910910910910910910910910910910|
-      {2:    }9109109109109109109109109109                  |
-      {2:  2 }1101101101101101101101101101101101101101101101|
-      {2:    }1011011011011011011011011011011011011011011011|
-      {2:    }0110110110110110110110110110                  |
-      {2:  1 }1111111111111111111111111111111111111111111111|
-      {2:    }1111111111111111111111111111111111111111111111|
-      {2:    }1111111111111111111111111111                  |
-      {1:113 }^1121121121121121121121121121121121121121121121|
-      {1:    }1211211211211211211211211211211211211211211211|
-      {1:    }2112112112112112112112112112                  |
-      {3:  1 }1131131131131131131131131131131131131131131131|
-      {3:    }1311311311311311311311311311311311311311311311|
-      {3:    }3113113113113113113113113113                  |
-      {3:  2 }1141141141141141141141141141141141141141141{4:@@@}|
-                                                        |
-    ]])
-  end)
-
-  -- oldtest: Test_relativenumber_callback()
-  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:~                                                 }|*3
-                                                        |
-    ]],
-      timeout = 100,
-    })
-    screen:expect({
-      grid = [[
-      {1:  0 }^aaaaa                                         |
-      {1:  1 }bbbbb                                         |
-      {1:  2 }ccccc                                         |
-      {1:  3 }ddddd                                         |
-      {2:~                                                 }|*3
-                                                        |
-    ]],
-    })
-  end)
-end)
-
 describe("'winhighlight' highlight", function()
   local screen
 
diff --git a/test/old/testdir/test_number.vim b/test/old/testdir/test_number.vim
index 6ac3c4cfe4..b57c1ed2c5 100644
--- a/test/old/testdir/test_number.vim
+++ b/test/old/testdir/test_number.vim
@@ -146,8 +146,7 @@ func Test_number_with_linewrap1()
   call s:close_windows()
 endfunc
 
-" Pending: https://groups.google.com/forum/#!topic/vim_dev/tzNKP7EDWYI
-func XTest_number_with_linewrap2()
+func Test_number_with_linewrap2()
   call s:test_windows(3, 20)
   normal! 61ia
   setl number wrap
@@ -164,8 +163,7 @@ func XTest_number_with_linewrap2()
   call s:close_windows()
 endfunc
 
-" Pending: https://groups.google.com/forum/#!topic/vim_dev/tzNKP7EDWYI
-func XTest_number_with_linewrap3()
+func Test_number_with_linewrap3()
   call s:test_windows(4, 20)
   normal! 81ia
   setl number wrap
@@ -174,7 +172,7 @@ func XTest_number_with_linewrap3()
   call s:validate_cursor()
   let lines = s:screen_lines(1, 4)
   let expect = [
-\ "aaaaaaaa",
+\ "<<<aaaaa",
 \ "aaaaaaaa",
 \ "aaaaaaaa",
 \ "a       ",
@@ -349,6 +347,31 @@ func Test_relativenumber_callback()
   call StopVimInTerminal(buf)
 endfunc
 
+" Test that line numbers below inserted/deleted lines are updated.
+func Test_number_insert_delete_lines()
+  CheckScreendump
+
+  let lines =<< trim END
+      call setline(1, range(1, 7))
+      set number
+      call cursor(2, 1)
+  END
+  call writefile(lines, 'Xnumber_insert_delete_lines', 'D')
+
+  let buf = RunVimInTerminal('-S Xnumber_insert_delete_lines', #{rows: 8})
+  call VerifyScreenDump(buf, 'Test_number_insert_delete_lines_1', {})
+  call term_sendkeys(buf, "dd")
+  call VerifyScreenDump(buf, 'Test_number_insert_delete_lines_2', {})
+  call term_sendkeys(buf, "P")
+  call VerifyScreenDump(buf, 'Test_number_insert_delete_lines_1', {})
+  call term_sendkeys(buf, "2dd")
+  call VerifyScreenDump(buf, 'Test_number_insert_delete_lines_3', {})
+  call term_sendkeys(buf, "P")
+  call VerifyScreenDump(buf, 'Test_number_insert_delete_lines_1', {})
+
+  call StopVimInTerminal(buf)
+endfunc
+
 " Test for displaying line numbers with 'rightleft'
 func Test_number_rightleft()
   CheckFeature rightleft