fix(screen): redraw the ruler for a current floating window

Semi-regression. The "ruler" behavior for a floating window
was never really specified but in practice followed the users
cursor movements in normal mode in a focused float, which seems
like a reasonable behavior to now specify.

src/nvim/drawscreen.c

@@ -746,7 +746,7 @@ void show_cursor_info_later(bool force)
       || curwin->w_topfill != curwin->w_stl_topfill
       || empty_line != curwin->w_stl_empty
       || state != curwin->w_stl_state) {
-    if ((curwin->w_status_height || global_stl_height())) {
+    if (curwin->w_status_height || global_stl_height()) {
       curwin->w_redr_status = true;
     } else {
       redraw_cmdline = true;

src/nvim/screen.c

@@ -608,7 +608,7 @@ int showmode(void)
 
   // If the last window has no status line and global statusline is disabled,
   // the ruler is after the mode message and must be redrawn
-  win_T *last = lastwin_nofloating();
+  win_T *last = curwin->w_floating ? curwin : lastwin_nofloating();
   if (redrawing() && last->w_status_height == 0 && global_stl_height() == 0) {
     win_redr_ruler(last);
   }

test/functional/ui/float_spec.lua

@@ -2184,6 +2184,98 @@ describe('float window', function()
       end
     end)
 
+    it('show ruler of current floating window', function()
+      command 'set ruler'
+      local buf = meths.create_buf(false, false)
+      meths.buf_set_lines(buf, 0, -1, true, {'aaa aab ',
+                                             'abb acc '})
+      meths.open_win(buf, true, {relative='editor', width=9, height=3, row=0, col=5})
+      feed 'gg'
+
+      if multigrid then
+        screen:expect{grid=[[
+        ## grid 1
+          [2:----------------------------------------]|
+          [2:----------------------------------------]|
+          [2:----------------------------------------]|
+          [2:----------------------------------------]|
+          [2:----------------------------------------]|
+          [2:----------------------------------------]|
+          [3:----------------------------------------]|
+        ## grid 2
+                                                  |
+          {0:~                                       }|
+          {0:~                                       }|
+          {0:~                                       }|
+          {0:~                                       }|
+          {0:~                                       }|
+        ## grid 3
+                                1,1           All |
+        ## grid 5
+          {1:^aaa aab  }|
+          {1:abb acc  }|
+          {2:~        }|
+        ]], float_pos={
+          [5] = {{id = 1002}, "NW", 1, 0, 5, true, 50};
+        }, win_viewport={
+          [2] = {win = {id = 1000}, topline = 0, botline = 2, curline = 0, curcol = 0, linecount = 1, sum_scroll_delta = 0};
+          [5] = {win = {id = 1002}, topline = 0, botline = 3, curline = 0, curcol = 0, linecount = 2, sum_scroll_delta = 0};
+        }}
+      else
+        screen:expect{grid=[[
+               {1:^aaa aab  }                          |
+          {0:~    }{1:abb acc  }{0:                          }|
+          {0:~    }{2:~        }{0:                          }|
+          {0:~                                       }|
+          {0:~                                       }|
+          {0:~                                       }|
+                                1,1           All |
+        ]]}
+      end
+
+      feed 'w'
+      if multigrid then
+        screen:expect{grid=[[
+        ## grid 1
+          [2:----------------------------------------]|
+          [2:----------------------------------------]|
+          [2:----------------------------------------]|
+          [2:----------------------------------------]|
+          [2:----------------------------------------]|
+          [2:----------------------------------------]|
+          [3:----------------------------------------]|
+        ## grid 2
+                                                  |
+          {0:~                                       }|
+          {0:~                                       }|
+          {0:~                                       }|
+          {0:~                                       }|
+          {0:~                                       }|
+        ## grid 3
+                                1,5           All |
+        ## grid 5
+          {1:aaa ^aab  }|
+          {1:abb acc  }|
+          {2:~        }|
+        ]], float_pos={
+          [5] = {{id = 1002}, "NW", 1, 0, 5, true, 50};
+        }, win_viewport={
+          [2] = {win = {id = 1000}, topline = 0, botline = 2, curline = 0, curcol = 0, linecount = 1, sum_scroll_delta = 0};
+          [5] = {win = {id = 1002}, topline = 0, botline = 3, curline = 0, curcol = 4, linecount = 2, sum_scroll_delta = 0};
+        }}
+      else
+        screen:expect{grid=[[
+               {1:aaa ^aab  }                          |
+          {0:~    }{1:abb acc  }{0:                          }|
+          {0:~    }{2:~        }{0:                          }|
+          {0:~                                       }|
+          {0:~                                       }|
+          {0:~                                       }|
+                                1,5           All |
+        ]]}
+      end
+    end)
+
     it('can have minimum size', function()
       insert("the background text")
       local buf = meths.create_buf(false, true)

test/functional/ui/screen.lua

@@ -1351,7 +1351,7 @@ local function fmt_ext_state(name, state)
     for k,v in pairs(state) do
       str = (str.."  ["..k.."] = {win = {id = "..v.win.id.."}, topline = "
              ..v.topline..", botline = "..v.botline..", curline = "..v.curline
-             ..", curcol = "..v.curcol..", linecount = "..v.linecount..", scroll_delta = "..v.scroll_delta.."};\n")
+             ..", curcol = "..v.curcol..", linecount = "..v.linecount..", sum_scroll_delta = "..v.sum_scroll_delta.."};\n")
     end
     return str .. "}"
   elseif name == "float_pos" then