Merge pull request #14779 from tjdevries/tjdevries/vim_opt_fixes

An assortment of various vim.opt fixups.

src/nvim/option.c

@@ -7765,6 +7765,7 @@ static Dictionary vimoption2dict(vimoption_T *opt)
     }
     PUT(dict, "type", CSTR_TO_OBJ(type));
     PUT(dict, "default", def);
+    PUT(dict, "allows_duplicates", BOOL(!(opt->flags & P_NODUP)));
 
     return dict;
 }

src/nvim/options.lua

@@ -3152,7 +3152,7 @@ return {
       full_name='wildmode', abbreviation='wim',
       short_desc=N_("mode for 'wildchar' command-line expansion"),
       type='string', list='onecomma', scope={'global'},
-      deny_duplicates=true,
+      deny_duplicates=false,
       vim=true,
       varname='p_wim',
       defaults={if_true={vi="", vim="full"}}