## Coverage Report

#### Created: 2025-11-22 06:00

next uncovered line (L), next uncovered region (R), next uncovered branch (B)

    /Users/andrewlamb/Software/datafusion/datafusion/functions-aggregate-common/src/order.rs

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    // Licensed to the Apache Software Foundation (ASF) under one
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    // or more contributor license agreements.  See the NOTICE file
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    // distributed with this work for additional information
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    // regarding copyright ownership.  The ASF licenses this file
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    // to you under the Apache License, Version 2.0 (the
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    // "License"); you may not use this file except in compliance
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    // with the License.  You may obtain a copy of the License at
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    //
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    //   http://www.apache.org/licenses/LICENSE-2.0
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    //
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    // Unless required by applicable law or agreed to in writing,
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    // software distributed under the License is distributed on an
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    // "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
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    // KIND, either express or implied.  See the License for the
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    // specific language governing permissions and limitations
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    // under the License.
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    /// Represents the sensitivity of an aggregate expression to ordering.
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    #[derive(Debug, PartialEq, Eq, Clone, Copy)]
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    pub enum AggregateOrderSensitivity {
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        /// Indicates that the aggregate expression is insensitive to ordering.
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        /// Ordering at the input is not important for the result of the aggregator.
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        Insensitive,
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        /// Indicates that the aggregate expression has a hard requirement on ordering.
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        /// The aggregator cannot produce a correct result unless its ordering
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        /// requirement is satisfied.
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        HardRequirement,
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        /// Indicates that the aggregator is more efficient when the input is ordered
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        /// but can still produce its result correctly regardless of the input ordering.
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        /// This is similar to, but stronger than, [`Self::Beneficial`].
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        ///
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        /// Similarly to [`Self::HardRequirement`], when possible DataFusion will insert
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        /// a `SortExec`, to reorder the input to match the SoftRequirement. However,
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        /// when such a `SortExec` cannot be inserted, (for example, due to conflicting
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        /// [`Self::HardRequirement`] with other ordered aggregates in the query),
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        /// the aggregate function will still execute, without the preferred order, unlike
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        /// with [`Self::HardRequirement`]
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        SoftRequirement,
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        /// Indicates that ordering is beneficial for the aggregate expression in terms
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        /// of evaluation efficiency. The aggregator can produce its result efficiently
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        /// when its required ordering is satisfied; however, it can still produce the
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        /// correct result (albeit less efficiently) when its required ordering is not met.
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        Beneficial,
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    }
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    impl AggregateOrderSensitivity {
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        pub fn is_insensitive(&self) -> bool {
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            self.eq(&AggregateOrderSensitivity::Insensitive)
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        }
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        pub fn is_beneficial(&self) -> bool {
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            matches!(self, Self::SoftRequirement | Self::Beneficial)
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        }
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        pub fn hard_requires(&self) -> bool {
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            self.eq(&AggregateOrderSensitivity::HardRequirement)
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        }
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    }