Method eval_with_fast_window_agg

src/expr/src/relation/func.rs:2230–2264

Like `eval`, but it's given a [OneByOneAggr]. If `self` is a `WindowAggregate`, then the given [OneByOneAggr] will be used to evaluate the wrapped aggregate inside the `WindowAggregate`. If `self` is not a `WindowAggregate`, then it simply calls `eval`.

(
        &self,
        datums: I,
        temp_storage: &'a RowArena,
    )

    /// the given [OneByOneAggr] will be used to evaluate the wrapped aggregate inside the
    /// `WindowAggregate`. If `self` is not a `WindowAggregate`, then it simply calls `eval`.
    pub fn eval_with_fast_window_agg<'a, I, W>(
        &self,
        datums: I,
        temp_storage: &'a RowArena,
    ) -> Datum<'a>
    where
        I: IntoIterator<Item = (Datum<'a>, Diff)>,
        W: OneByOneAggr,
    {
        match self {
            AggregateFunc::WindowAggregate {
                wrapped_aggregate,
                order_by,
                window_frame,
            } => window_aggr::<_, W>(
                expand_counts(datums),
                temp_storage,
                wrapped_aggregate,
                order_by,
                window_frame,
            ),
            AggregateFunc::FusedWindowAggregate {
                wrapped_aggregates,
                order_by,
                window_frame,
            } => fused_window_aggr::<_, W>(
                expand_counts(datums),
                temp_storage,
                wrapped_aggregates,
                order_by,
                window_frame,
            ),
            _ => self.eval(datums, temp_storage),
        }
    }

    pub fn eval_with_unnest_list<'a, I, W>(
        &self,