test: screen.lua can check win_pos #32373

Also remove a hack in the multigrid "with winbar" test.

test/functional/ui/multigrid_spec.lua

@@ -2407,6 +2407,22 @@ describe('ext_multigrid', function()
 
   it('with winbar', function()
     command('split')
+    local win_pos ={
+      [2] = {
+        height = 5,
+        startcol = 0,
+        startrow = 7,
+        width = 53,
+        win = 1000
+      },
+      [4] = {
+        height = 6,
+        startcol = 0,
+        startrow = 0,
+        width = 53,
+        win = 1001
+      }
+    }
     screen:expect{grid=[[
     ## grid 1
       [4:-----------------------------------------------------]|*6
@@ -2428,15 +2444,7 @@ describe('ext_multigrid', function()
     }, win_viewport_margins={
       [2] = {win = 1000, top = 0, bottom = 0, left = 0, right = 0};
       [4] = {win = 1001, top = 0, bottom = 0, left = 0, right = 0};
-    }}
-
-    -- XXX: hack to get notifications. Could use next_msg() also.
-    local orig_handle_win_pos = screen._handle_win_pos
-    local win_pos = {}
-    function screen._handle_win_pos(self, grid, win, startrow, startcol, width, height)
-      table.insert(win_pos, {grid, win, startrow, startcol, width, height})
-      orig_handle_win_pos(self, grid, win, startrow, startcol, width, height)
-    end
+    }, win_pos = win_pos }
 
     command('setlocal winbar=very%=bar')
     screen:expect{grid=[[
@@ -2461,8 +2469,7 @@ describe('ext_multigrid', function()
     }, win_viewport_margins={
       [2] = {win = 1000, top = 0, bottom = 0, left = 0, right = 0};
       [4] = {win = 1001, top = 1, bottom = 0, left = 0, right = 0};
-    }}
-    eq({}, win_pos)
+    }, win_pos = win_pos }
 
     command('setlocal winbar=')
     screen:expect{grid=[[
@@ -2486,8 +2493,7 @@ describe('ext_multigrid', function()
     }, win_viewport_margins={
       [2] = {win = 1000, top = 0, bottom = 0, left = 0, right = 0};
       [4] = {win = 1001, top = 0, bottom = 0, left = 0, right = 0};
-    }}
-    eq({}, win_pos)
+    }, win_pos = win_pos }
   end)
 
   it('with winbar dragging statusline with mouse works correctly', function()

test/functional/ui/screen.lua

@@ -338,6 +338,7 @@ local ext_keys = {
   'showmode',
   'showcmd',
   'ruler',
+  'win_pos',
   'float_pos',
   'win_viewport',
   'win_viewport_margins',
@@ -357,6 +358,7 @@ local expect_keys = {
   request_cb = true,
   hl_groups = true,
   extmarks = true,
+  win_pos = true,
 }
 
 for _, v in ipairs(ext_keys) do
@@ -426,6 +428,7 @@ end
 --- @field mouse_enabled? boolean
 ---
 --- @field win_viewport? table<integer,table<string,integer>>
+--- @field win_pos? table<integer,table<string,integer>>
 --- @field float_pos? [integer,integer]
 --- @field hl_groups? table<string,integer>
 ---
@@ -628,6 +631,9 @@ screen:redraw_debug() to show all intermediate screen states.]]
     if expected.win_viewport_margins == nil then
       extstate.win_viewport_margins = nil
     end
+    if expected.win_pos == nil then
+      extstate.win_pos = nil
+    end
 
     if expected.float_pos then
       expected.float_pos = deepcopy(expected.float_pos)
@@ -1520,6 +1526,7 @@ function Screen:_extstate_repr(attr_state)
     float_pos = self.float_pos,
     win_viewport = win_viewport,
     win_viewport_margins = win_viewport_margins,
+    win_pos = self.win_position,
   }
 end