vim-patch:8.2.0257: cannot recognize a terminal in a popup window

Problem:    Cannot recognize a terminal in a popup window.
Solution:   Add the win_gettype() function.
00f3b4e007

runtime/doc/eval.txt

@@ -2487,6 +2487,7 @@ wait({timeout}, {condition}[, {interval}])
 wildmenumode()			Number	whether 'wildmenu' mode is active
 win_findbuf({bufnr})		List	find windows containing {bufnr}
 win_getid([{win} [, {tab}]])	Number	get |window-ID| for {win} in {tab}
+win_gettype([{nr}])		String	type of window {nr}
 win_gotoid({expr})		Number	go to |window-ID| {expr}
 win_id2tabwin({expr})		List	get tab and window nr from |window-ID|
 win_id2win({expr})		Number	get window nr from |window-ID|
@@ -9277,6 +9278,21 @@ win_getid([{win} [, {tab}]])				*win_getid()*
 		number {tab}.  The first tab has number one.
 		Return zero if the window cannot be found.
 
+win_gettype([{nr}])					*win_gettype()*
+		Return the type of the window:
+			"popup"		popup window |popup|
+			"command"	command-line window |cmdwin|
+			(empty)		normal window
+			"unknown"	window {nr} not found
+
+		When {nr} is omitted return the type of the current window.
+		When {nr} is given return the type of this window by number or
+		|window-ID|.
+
+		Also see the 'buftype' option.  When running a terminal in a
+		popup window then 'buftype' is "terminal" and win_gettype()
+		returns "popup".
+
 win_gotoid({expr})					*win_gotoid()*
 		Go to window with ID {expr}.  This may also change the current
 		tabpage.

src/nvim/eval.lua

@@ -385,6 +385,7 @@ return {
     wildmenumode={},
     win_findbuf={args=1},
     win_getid={args={0,2}},
+    win_gettype={args={0,1}},
     win_gotoid={args=1},
     win_id2tabwin={args=1},
     win_id2win={args=1},

src/nvim/eval/funcs.c

@@ -10992,6 +10992,27 @@ static void f_win_getid(typval_T *argvars, typval_T *rettv, FunPtr fptr)
   rettv->vval.v_number = win_getid(argvars);
 }
 
+/// "win_gettype(nr)" function
+static void f_win_gettype(typval_T *argvars, typval_T *rettv, FunPtr fptr)
+{
+  win_T *wp = curwin;
+
+  rettv->v_type = VAR_STRING;
+  rettv->vval.v_string = NULL;
+  if (argvars[0].v_type != VAR_UNKNOWN) {
+    wp = find_win_by_nr_or_id(&argvars[0]);
+    if (wp == NULL) {
+      rettv->vval.v_string = vim_strsave((char_u *)"unknown");
+      return;
+    }
+  }
+  if (wp->w_floating) {
+    rettv->vval.v_string = vim_strsave((char_u *)"popup");
+  } else if (wp == curwin && cmdwin_type != 0) {
+    rettv->vval.v_string = vim_strsave((char_u *)"command");
+  }
+}
+
 /// "win_gotoid()" function
 static void f_win_gotoid(typval_T *argvars, typval_T *rettv, FunPtr fptr)
 {

src/nvim/testdir/test_cmdline.vim

@@ -806,12 +806,14 @@ func Test_cmdwin_cedit()
   let g:cmd_wintype = ''
   func CmdWinType()
       let g:cmd_wintype = getcmdwintype()
+      let g:wintype = win_gettype()
       return ''
   endfunc
 
   call feedkeys("\<C-c>a\<C-R>=CmdWinType()\<CR>\<CR>")
   echo input('')
   call assert_equal('@', g:cmd_wintype)
+  call assert_equal('command', g:wintype)
 
   set cedit&vim
   delfunc CmdWinType