Where if extension linq method C#

WhereIf.cs

    public static class Where
    {
        private static string nomeMetodoWhere = "where";

        public static IQueryable<TSource> WhereIf<TSource>(this IQueryable<TSource> source, Expression<Func<TSource, int, bool>> predicate, bool condicao)
        {

            if (source == null)
                throw new Exception("source");

            if (predicate == null)
                throw new Exception("predicate");

            if (condicao)
            {
                var methodCallExpression = Expression.Call(
                       typeof(Queryable),
                       nomeMetodoWhere,
                       new Type[] { source.ElementType },
                       source.Expression,
                       Expression.Lambda<Func<TSource, int, bool>>(predicate.Body, predicate.Parameters)
                       );

                return source.Provider.CreateQuery<TSource>(methodCallExpression);
            }

            return source;
        }

        public static IQueryable<TSource> WhereIf<TSource>(this IQueryable<TSource> source, Expression<Func<TSource, int>> predicate, bool condicao)
        {

            if (source == null)
                throw new Exception("source");

            if (predicate == null)
                throw new Exception("predicate");

            if (condicao)
            {
                var methodCallExpression = Expression.Call(
                    typeof(Queryable),
                    nomeMetodoWhere,
                    new Type[] { source.ElementType },
                    source.Expression,
                    Expression.Lambda<Func<TSource, int>>(predicate.Body, predicate.Parameters));

                return source.Provider.CreateQuery<TSource>(methodCallExpression);
            }

            return source;
        }

        public static IQueryable<TSource> WhereIf<TSource>(this IQueryable<TSource> source, Expression<Func<TSource, bool>> predicate, bool condicao)
        {

            if (source == null)
                throw new Exception("source");
            if (predicate == null)
                throw new Exception("predicate");

            if (condicao)
            {

                var methodCallExpression = Expression.Call(
                    typeof(Queryable),
                    nomeMetodoWhere,
                    new Type[] { source.ElementType },
                    source.Expression,
                    Expression.Lambda<Func<TSource, bool>>(predicate.Body, predicate.Parameters)
                    );

                return source.Provider.CreateQuery<TSource>(methodCallExpression);

              
            }

            return source;
        }


    }