patch 8.2.1496: Vim9: cannot use " #" in a mapping

Problem:    Vim9: cannot use " #" in a mapping.
Solution:   Do not remove a comment with the EX_NOTRLCOM flag. (closes #6746)

Author: brammool

src/ex_docmd.c

@@ -4604,6 +4604,7 @@ separate_nextcmd(exarg_T *eap)
 #ifdef FEAT_EVAL
 		|| (*p == '#'
 		    && in_vim9script()
+		    && !(eap->argt & EX_NOTRLCOM)
 		    && p[1] != '{'
 		    && p > eap->cmd && VIM_ISWHITE(p[-1]))
 #endif

src/testdir/test_vim9_cmd.vim

@@ -286,5 +286,14 @@ def Test_eval_command()
   unlet g:val
 enddef
 
+def Test_map_command()
+  let lines =<< trim END
+      nnoremap <F3> :echo 'hit F3 #'<CR>
+      assert_equal(":echo 'hit F3 #'<CR>", maparg("<F3>", "n"))
+  END
+  CheckDefSuccess(lines)
+  CheckScriptSuccess(['vim9script'] + lines)
+enddef
+
 
 " vim: ts=8 sw=2 sts=2 expandtab tw=80 fdm=marker

src/version.c

@@ -754,6 +754,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1496,
 /**/
     1495,
 /**/

src/vim9compile.c

@@ -6251,6 +6251,7 @@ compile_exec(char_u *line, exarg_T *eap, cctx_T *cctx)
 	    usefilter = TRUE;
 	if ((argt & EX_TRLBAR) && !usefilter)
 	{
+	    eap->argt = argt;
 	    separate_nextcmd(eap);
 	    if (eap->nextcmd != NULL)
 		nextcmd = eap->nextcmd;