fix(events)!: trigger CursorMoved later on switching window (#23711)

runtime/doc/autocmd.txt

@@ -505,8 +505,7 @@ CursorMoved			After the cursor was moved in Normal or Visual
 				"x", "rx" or "p".
 				Not always triggered when there is typeahead,
 				while executing commands in a script file, or
-				when an operator is pending. Always triggered
-				when moving to another window.
+				when an operator is pending.
 				For an example see |match-parens|.
 				Note: Cannot be skipped with |:noautocmd|.
 				Careful: This is triggered very often, don't

runtime/doc/news.txt

@@ -30,6 +30,8 @@ The following changes may require adaptations in user config or plugins.
     set mousemodel=popup
     set keymodel=startsel,stopsel
 <
+• When switching windows, |CursorMoved| autocommands trigger when Nvim is back
+  in the main loop rather than immediately. This is more compatible with Vim.
 
 • |LspRequest| autocmd was promoted from a |User| autocmd to a first class
   citizen.

src/nvim/window.c

@@ -4903,8 +4903,7 @@ static void win_enter_ext(win_T *const wp, const int flags)
     if (other_buffer) {
       apply_autocmds(EVENT_BUFENTER, NULL, NULL, false, curbuf);
     }
-    apply_autocmds(EVENT_CURSORMOVED, NULL, NULL, false, curbuf);
-    curwin->w_last_cursormoved = curwin->w_cursor;
+    curwin->w_last_cursormoved.lnum = 0;
   }
 
   maketitle();

test/functional/autocmd/cursormoved_spec.lua

@@ -5,19 +5,23 @@ local eq = helpers.eq
 local eval = helpers.eval
 local funcs = helpers.funcs
 local source = helpers.source
+local command = helpers.command
 
 describe('CursorMoved', function()
   before_each(clear)
 
-  it('is triggered by changing windows', function()
+  it('is triggered after BufEnter when changing or splitting windows #11878 #12031', function()
     source([[
-    let g:cursormoved = 0
-    vsplit
-    autocmd CursorMoved * let g:cursormoved += 1
-    wincmd w
-    wincmd w
+    call setline(1, 'foo')
+    let g:log = []
+    autocmd BufEnter * let g:log += ['BufEnter' .. expand("<abuf>")]
+    autocmd CursorMoved * let g:log += ['CursorMoved' .. expand("<abuf>")]
     ]])
-    eq(2, eval('g:cursormoved'))
+    eq({}, eval('g:log'))
+    command('new')
+    eq({'BufEnter2', 'CursorMoved2'}, eval('g:log'))
+    command('wincmd w')
+    eq({'BufEnter2', 'CursorMoved2', 'BufEnter1', 'CursorMoved1'}, eval('g:log'))
   end)
 
   it("is not triggered by functions that don't change the window", function()

test/functional/ui/float_spec.lua

@@ -79,7 +79,7 @@ describe('float window', function()
           api.nvim_buf_set_lines(buf, 0, -1, true, contents)
           local winnr = vim.fn.win_id2win(floatwin)
           api.nvim_command('wincmd p')
-          api.nvim_command('autocmd CursorMoved * ++once '..winnr..'wincmd c')
+          api.nvim_command('autocmd BufEnter * ++once '..winnr..'wincmd c')
           return buf, floatwin
         end
         crashes{'foo'}