V8: Wildcards in tree searches causes YSODs (#7330)

src/Umbraco.Core/Persistence/Querying/ExpressionVisitorBase.cs

@@ -744,7 +744,9 @@ namespace Umbraco.Core.Persistence.Querying
 
             var c = exp[0];
             return (c == '"' || c == '`' || c == '\'') && exp[exp.Length - 1] == c
-                ? exp.Substring(1, exp.Length - 2)
+                ? exp.Length == 1
+                    ? string.Empty
+                    : exp.Substring(1, exp.Length - 2)
                 : exp;
         }
     }

src/Umbraco.Web/Search/UmbracoTreeSearcher.cs

@@ -186,6 +186,9 @@ namespace Umbraco.Web.Search
 
             var allLangs = _languageService.GetAllLanguages().Select(x => x.IsoCode.ToLowerInvariant()).ToList();
 
+            // the chars [*-_] in the query will mess everything up so let's remove those
+            query = Regex.Replace(query, "[\\*\\-_]", "");
+
             //check if text is surrounded by single or double quotes, if so, then exact match
             var surroundedByQuotes = Regex.IsMatch(query, "^\".*?\"$")
                                      || Regex.IsMatch(query, "^\'.*?\'$");