## Coverage Report

#### Created: 2025-08-26 07:03

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    /Users/andrewlamb/Software/arrow-rs/arrow-array/src/builder/generic_list_view_builder.rs

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    Source
    1
    // Licensed to the Apache Software Foundation (ASF) under one
    2
    // or more contributor license agreements.  See the NOTICE file
    3
    // distributed with this work for additional information
    4
    // regarding copyright ownership.  The ASF licenses this file
    5
    // to you under the Apache License, Version 2.0 (the
    6
    // "License"); you may not use this file except in compliance
    7
    // with the License.  You may obtain a copy of the License at
    8
    //
    9
    //   http://www.apache.org/licenses/LICENSE-2.0
    10
    //
    11
    // Unless required by applicable law or agreed to in writing,
    12
    // software distributed under the License is distributed on an
    13
    // "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
    14
    // KIND, either express or implied.  See the License for the
    15
    // specific language governing permissions and limitations
    16
    // under the License.
    17
    18
    use crate::builder::ArrayBuilder;
    19
    use crate::{ArrayRef, GenericListViewArray, OffsetSizeTrait};
    20
    use arrow_buffer::{Buffer, NullBufferBuilder, ScalarBuffer};
    21
    use arrow_schema::{Field, FieldRef};
    22
    use std::any::Any;
    23
    use std::sync::Arc;
    24
    25
    /// Builder for [`GenericListViewArray`]
    26
    #[derive(Debug)]
    27
    pub struct GenericListViewBuilder<OffsetSize: OffsetSizeTrait, T: ArrayBuilder> {
    28
        offsets_builder: Vec<OffsetSize>,
    29
        sizes_builder: Vec<OffsetSize>,
    30
        null_buffer_builder: NullBufferBuilder,
    31
        values_builder: T,
    32
        field: Option<FieldRef>,
    33
        current_offset: OffsetSize,
    34
    }
    35
    36
    impl<O: OffsetSizeTrait, T: ArrayBuilder + Default> Default for GenericListViewBuilder<O, T> {
    37
        fn default() -> Self {
    38
            Self::new(T::default())
    39
        }
    40
    }
    41
    42
    impl<OffsetSize: OffsetSizeTrait, T: ArrayBuilder> ArrayBuilder
    43
        for GenericListViewBuilder<OffsetSize, T>
    44
    {
    45
        /// Returns the builder as a non-mutable `Any` reference.
    46
    0
        fn as_any(&self) -> &dyn Any {
    47
    0
            self
    48
    0
        }
    49
    50
        /// Returns the builder as a mutable `Any` reference.
    51
    0
        fn as_any_mut(&mut self) -> &mut dyn Any {
    52
    0
            self
    53
    0
        }
    54
    55
        /// Returns the boxed builder as a box of `Any`.
    56
    0
        fn into_box_any(self: Box<Self>) -> Box<dyn Any> {
    57
    0
            self
    58
    0
        }
    59
    60
        /// Returns the number of array slots in the builder
    61
    0
        fn len(&self) -> usize {
    62
    0
            self.null_buffer_builder.len()
    63
    0
        }
    64
    65
        /// Builds the array and reset this builder.
    66
    0
        fn finish(&mut self) -> ArrayRef {
    67
    0
            Arc::new(self.finish())
    68
    0
        }
    69
    70
        /// Builds the array without resetting the builder.
    71
    0
        fn finish_cloned(&self) -> ArrayRef {
    72
    0
            Arc::new(self.finish_cloned())
    73
    0
        }
    74
    }
    75
    76
    impl<OffsetSize: OffsetSizeTrait, T: ArrayBuilder> GenericListViewBuilder<OffsetSize, T> {
    77
        /// Creates a new [`GenericListViewBuilder`] from a given values array builder
    78
        pub fn new(values_builder: T) -> Self {
    79
            let capacity = values_builder.len();
    80
            Self::with_capacity(values_builder, capacity)
    81
        }
    82
    83
        /// Creates a new [`GenericListViewBuilder`] from a given values array builder
    84
        /// `capacity` is the number of items to pre-allocate space for in this builder
    85
    0
        pub fn with_capacity(values_builder: T, capacity: usize) -> Self {
    86
    0
            let offsets_builder = Vec::with_capacity(capacity);
    87
    0
            let sizes_builder = Vec::with_capacity(capacity);
    88
    0
            Self {
    89
    0
                offsets_builder,
    90
    0
                null_buffer_builder: NullBufferBuilder::new(capacity),
    91
    0
                values_builder,
    92
    0
                sizes_builder,
    93
    0
                field: None,
    94
    0
                current_offset: OffsetSize::zero(),
    95
    0
            }
    96
    0
        }
    97
    98
        ///
    99
        /// By default a nullable field is created with the name `item`
    100
        ///
    101
        /// Note: [`Self::finish`] and [`Self::finish_cloned`] will panic if the
    102
        /// field's data type does not match that of `T`
    103
    0
        pub fn with_field(self, field: impl Into<FieldRef>) -> Self {
    104
    0
            Self {
    105
    0
                field: Some(field.into()),
    106
    0
                ..self
    107
    0
            }
    108
    0
        }
    109
    }
    110
    111
    impl<OffsetSize: OffsetSizeTrait, T: ArrayBuilder> GenericListViewBuilder<OffsetSize, T>
    112
    where
    113
        T: 'static,
    114
    {
    115
        /// Returns the child array builder as a mutable reference.
    116
        ///
    117
        /// This mutable reference can be used to append values into the child array builder,
    118
        /// but you must call [`append`](#method.append) to delimit each distinct list value.
    119
        pub fn values(&mut self) -> &mut T {
    120
            &mut self.values_builder
    121
        }
    122
    123
        /// Returns the child array builder as an immutable reference
    124
        pub fn values_ref(&self) -> &T {
    125
            &self.values_builder
    126
        }
    127
    128
        /// Finish the current variable-length list array slot
    129
        ///
    130
        /// # Panics
    131
        ///
    132
        /// Panics if the length of [`Self::values`] exceeds `OffsetSize::MAX`
    133
        #[inline]
    134
        pub fn append(&mut self, is_valid: bool) {
    135
            self.offsets_builder.push(self.current_offset);
    136
            self.sizes_builder.push(
    137
                OffsetSize::from_usize(
    138
                    self.values_builder.len() - self.current_offset.to_usize().unwrap(),
    139
                )
    140
                .unwrap(),
    141
            );
    142
            self.null_buffer_builder.append(is_valid);
    143
            self.current_offset = OffsetSize::from_usize(self.values_builder.len()).unwrap();
    144
        }
    145
    146
        /// Append value into this [`GenericListViewBuilder`]
    147
        #[inline]
    148
        pub fn append_value<I, V>(&mut self, i: I)
    149
        where
    150
            T: Extend<Option<V>>,
    151
            I: IntoIterator<Item = Option<V>>,
    152
        {
    153
            self.extend(std::iter::once(Some(i)))
    154
        }
    155
    156
        /// Append a null to this [`GenericListViewBuilder`]
    157
        ///
    158
        /// See [`Self::append_value`] for an example use.
    159
        #[inline]
    160
        pub fn append_null(&mut self) {
    161
            self.offsets_builder.push(self.current_offset);
    162
            self.sizes_builder.push(OffsetSize::from_usize(0).unwrap());
    163
            self.null_buffer_builder.append_null();
    164
        }
    165
    166
        /// Appends an optional value into this [`GenericListViewBuilder`]
    167
        ///
    168
        /// If `Some` calls [`Self::append_value`] otherwise calls [`Self::append_null`]
    169
        #[inline]
    170
        pub fn append_option<I, V>(&mut self, i: Option<I>)
    171
        where
    172
            T: Extend<Option<V>>,
    173
            I: IntoIterator<Item = Option<V>>,
    174
        {
    175
            match i {
    176
                Some(i) => self.append_value(i),
    177
                None => self.append_null(),
    178
            }
    179
        }
    180
    181
        /// Builds the [`GenericListViewArray`] and reset this builder.
    182
    0
        pub fn finish(&mut self) -> GenericListViewArray<OffsetSize> {
    183
    0
            let values = self.values_builder.finish();
    184
    0
            let nulls = self.null_buffer_builder.finish();
    185
    0
            let offsets = Buffer::from_vec(std::mem::take(&mut self.offsets_builder));
    186
    0
            self.current_offset = OffsetSize::zero();
    187
    188
            // Safety: Safe by construction
    189
    0
            let offsets = ScalarBuffer::from(offsets);
    190
    0
            let sizes = Buffer::from_vec(std::mem::take(&mut self.sizes_builder));
    191
    0
            let sizes = ScalarBuffer::from(sizes);
    192
    0
            let field = match &self.field {
    193
    0
                Some(f) => f.clone(),
    194
    0
                None => Arc::new(Field::new("item", values.data_type().clone(), true)),
    195
            };
    196
    0
            GenericListViewArray::new(field, offsets, sizes, values, nulls)
    197
    0
        }
    198
    199
        /// Builds the [`GenericListViewArray`] without resetting the builder.
    200
    0
        pub fn finish_cloned(&self) -> GenericListViewArray<OffsetSize> {
    201
    0
            let values = self.values_builder.finish_cloned();
    202
    0
            let nulls = self.null_buffer_builder.finish_cloned();
    203
    204
    0
            let offsets = Buffer::from_slice_ref(self.offsets_builder.as_slice());
    205
            // Safety: safe by construction
    206
    0
            let offsets = ScalarBuffer::from(offsets);
    207
    208
    0
            let sizes = Buffer::from_slice_ref(self.sizes_builder.as_slice());
    209
    0
            let sizes = ScalarBuffer::from(sizes);
    210
    211
    0
            let field = match &self.field {
    212
    0
                Some(f) => f.clone(),
    213
    0
                None => Arc::new(Field::new("item", values.data_type().clone(), true)),
    214
            };
    215
    216
    0
            GenericListViewArray::new(field, offsets, sizes, values, nulls)
    217
    0
        }
    218
    219
        /// Returns the current offsets buffer as a slice
    220
        pub fn offsets_slice(&self) -> &[OffsetSize] {
    221
            self.offsets_builder.as_slice()
    222
        }
    223
    }
    224
    225
    impl<O, B, V, E> Extend<Option<V>> for GenericListViewBuilder<O, B>
    226
    where
    227
        O: OffsetSizeTrait,
    228
        B: ArrayBuilder + Extend<E>,
    229
        V: IntoIterator<Item = E>,
    230
    {
    231
        #[inline]
    232
        fn extend<T: IntoIterator<Item = Option<V>>>(&mut self, iter: T) {
    233
            for v in iter {
    234
                match v {
    235
                    Some(elements) => {
    236
                        self.values_builder.extend(elements);
    237
                        self.append(true);
    238
                    }
    239
                    None => self.append(false),
    240
                }
    241
            }
    242
        }
    243
    }
    244
    245
    #[cfg(test)]
    246
    mod tests {
    247
        use super::*;
    248
        use crate::builder::{make_builder, Int32Builder, ListViewBuilder};
    249
        use crate::cast::AsArray;
    250
        use crate::types::Int32Type;
    251
        use crate::{Array, Int32Array};
    252
        use arrow_schema::DataType;
    253
    254
        fn test_generic_list_view_array_builder_impl<O: OffsetSizeTrait>() {
    255
            let values_builder = Int32Builder::with_capacity(10);
    256
            let mut builder = GenericListViewBuilder::<O, _>::new(values_builder);
    257
    258
            //  [[0, 1, 2], [3, 4, 5], [6, 7]]
    259
            builder.values().append_value(0);
    260
            builder.values().append_value(1);
    261
            builder.values().append_value(2);
    262
            builder.append(true);
    263
            builder.values().append_value(3);
    264
            builder.values().append_value(4);
    265
            builder.values().append_value(5);
    266
            builder.append(true);
    267
            builder.values().append_value(6);
    268
            builder.values().append_value(7);
    269
            builder.append(true);
    270
            let list_array = builder.finish();
    271
    272
            let list_values = list_array.values().as_primitive::<Int32Type>();
    273
            assert_eq!(list_values.values(), &[0, 1, 2, 3, 4, 5, 6, 7]);
    274
            assert_eq!(list_array.value_offsets(), [0, 3, 6].map(O::usize_as));
    275
            assert_eq!(list_array.value_sizes(), [3, 3, 2].map(O::usize_as));
    276
            assert_eq!(DataType::Int32, list_array.value_type());
    277
            assert_eq!(3, list_array.len());
    278
            assert_eq!(0, list_array.null_count());
    279
            assert_eq!(O::from_usize(6).unwrap(), list_array.value_offsets()[2]);
    280
            assert_eq!(O::from_usize(2).unwrap(), list_array.value_sizes()[2]);
    281
            for i in 0..2 {
    282
                assert!(list_array.is_valid(i));
    283
                assert!(!list_array.is_null(i));
    284
            }
    285
        }
    286
    287
        #[test]
    288
        fn test_list_view_array_builder() {
    289
            test_generic_list_view_array_builder_impl::<i32>()
    290
        }
    291
    292
        #[test]
    293
        fn test_large_list_view_array_builder() {
    294
            test_generic_list_view_array_builder_impl::<i64>()
    295
        }
    296
    297
        fn test_generic_list_view_array_builder_nulls_impl<O: OffsetSizeTrait>() {
    298
            let values_builder = Int32Builder::with_capacity(10);
    299
            let mut builder = GenericListViewBuilder::<O, _>::new(values_builder);
    300
    301
            //  [[0, 1, 2], null, [3, null, 5], [6, 7]]
    302
            builder.values().append_value(0);
    303
            builder.values().append_value(1);
    304
            builder.values().append_value(2);
    305
            builder.append(true);
    306
            builder.append(false);
    307
            builder.values().append_value(3);
    308
            builder.values().append_null();
    309
            builder.values().append_value(5);
    310
            builder.append(true);
    311
            builder.values().append_value(6);
    312
            builder.values().append_value(7);
    313
            builder.append(true);
    314
    315
            let list_array = builder.finish();
    316
    317
            assert_eq!(DataType::Int32, list_array.value_type());
    318
            assert_eq!(4, list_array.len());
    319
            assert_eq!(1, list_array.null_count());
    320
            assert_eq!(O::from_usize(3).unwrap(), list_array.value_offsets()[2]);
    321
            assert_eq!(O::from_usize(3).unwrap(), list_array.value_sizes()[2]);
    322
        }
    323
    324
        #[test]
    325
        fn test_list_view_array_builder_nulls() {
    326
            test_generic_list_view_array_builder_nulls_impl::<i32>()
    327
        }
    328
    329
        #[test]
    330
        fn test_large_list_view_array_builder_nulls() {
    331
            test_generic_list_view_array_builder_nulls_impl::<i64>()
    332
        }
    333
    334
        #[test]
    335
        fn test_list_view_array_builder_finish() {
    336
            let values_builder = Int32Array::builder(5);
    337
            let mut builder = ListViewBuilder::new(values_builder);
    338
    339
            builder.values().append_slice(&[1, 2, 3]);
    340
            builder.append(true);
    341
            builder.values().append_slice(&[4, 5, 6]);
    342
            builder.append(true);
    343
    344
            let mut arr = builder.finish();
    345
            assert_eq!(2, arr.len());
    346
            assert!(builder.is_empty());
    347
    348
            builder.values().append_slice(&[7, 8, 9]);
    349
            builder.append(true);
    350
            arr = builder.finish();
    351
            assert_eq!(1, arr.len());
    352
            assert!(builder.is_empty());
    353
        }
    354
    355
        #[test]
    356
        fn test_list_view_array_builder_finish_cloned() {
    357
            let values_builder = Int32Array::builder(5);
    358
            let mut builder = ListViewBuilder::new(values_builder);
    359
    360
            builder.values().append_slice(&[1, 2, 3]);
    361
            builder.append(true);
    362
            builder.values().append_slice(&[4, 5, 6]);
    363
            builder.append(true);
    364
    365
            let mut arr = builder.finish_cloned();
    366
            assert_eq!(2, arr.len());
    367
            assert!(!builder.is_empty());
    368
    369
            builder.values().append_slice(&[7, 8, 9]);
    370
            builder.append(true);
    371
            arr = builder.finish();
    372
            assert_eq!(3, arr.len());
    373
            assert!(builder.is_empty());
    374
        }
    375
    376
        #[test]
    377
        fn test_list_view_list_view_array_builder() {
    378
            let primitive_builder = Int32Builder::with_capacity(10);
    379
            let values_builder = ListViewBuilder::new(primitive_builder);
    380
            let mut builder = ListViewBuilder::new(values_builder);
    381
    382
            //  [[[1, 2], [3, 4]], [[5, 6, 7], null, [8]], null, [[9, 10]]]
    383
            builder.values().values().append_value(1);
    384
            builder.values().values().append_value(2);
    385
            builder.values().append(true);
    386
            builder.values().values().append_value(3);
    387
            builder.values().values().append_value(4);
    388
            builder.values().append(true);
    389
            builder.append(true);
    390
    391
            builder.values().values().append_value(5);
    392
            builder.values().values().append_value(6);
    393
            builder.values().values().append_value(7);
    394
            builder.values().append(true);
    395
            builder.values().append(false);
    396
            builder.values().values().append_value(8);
    397
            builder.values().append(true);
    398
            builder.append(true);
    399
    400
            builder.append(false);
    401
    402
            builder.values().values().append_value(9);
    403
            builder.values().values().append_value(10);
    404
            builder.values().append(true);
    405
            builder.append(true);
    406
    407
            let l1 = builder.finish();
    408
    409
            assert_eq!(4, l1.len());
    410
            assert_eq!(1, l1.null_count());
    411
    412
            assert_eq!(l1.value_offsets(), &[0, 2, 5, 5]);
    413
            assert_eq!(l1.value_sizes(), &[2, 3, 0, 1]);
    414
    415
            let l2 = l1.values().as_list_view::<i32>();
    416
    417
            assert_eq!(6, l2.len());
    418
            assert_eq!(1, l2.null_count());
    419
            assert_eq!(l2.value_offsets(), &[0, 2, 4, 7, 7, 8]);
    420
            assert_eq!(l2.value_sizes(), &[2, 2, 3, 0, 1, 2]);
    421
    422
            let i1 = l2.values().as_primitive::<Int32Type>();
    423
            assert_eq!(10, i1.len());
    424
            assert_eq!(0, i1.null_count());
    425
            assert_eq!(i1.values(), &[1, 2, 3, 4, 5, 6, 7, 8, 9, 10]);
    426
        }
    427
    428
        #[test]
    429
        fn test_extend() {
    430
            let mut builder = ListViewBuilder::new(Int32Builder::new());
    431
            builder.extend([
    432
                Some(vec![Some(1), Some(2), Some(7), None]),
    433
                Some(vec![]),
    434
                Some(vec![Some(4), Some(5)]),
    435
                None,
    436
            ]);
    437
    438
            let array = builder.finish();
    439
            assert_eq!(array.value_offsets(), [0, 4, 4, 6]);
    440
            assert_eq!(array.value_sizes(), [4, 0, 2, 0]);
    441
            assert_eq!(array.null_count(), 1);
    442
            assert!(array.is_null(3));
    443
            let elements = array.values().as_primitive::<Int32Type>();
    444
            assert_eq!(elements.values(), &[1, 2, 7, 0, 4, 5]);
    445
            assert_eq!(elements.null_count(), 1);
    446
            assert!(elements.is_null(3));
    447
        }
    448
    449
        #[test]
    450
        fn test_boxed_primitive_array_builder() {
    451
            let values_builder = make_builder(&DataType::Int32, 5);
    452
            let mut builder = ListViewBuilder::new(values_builder);
    453
    454
            builder
    455
                .values()
    456
                .as_any_mut()
    457
                .downcast_mut::<Int32Builder>()
    458
                .expect("should be an Int32Builder")
    459
                .append_slice(&[1, 2, 3]);
    460
            builder.append(true);
    461
    462
            builder
    463
                .values()
    464
                .as_any_mut()
    465
                .downcast_mut::<Int32Builder>()
    466
                .expect("should be an Int32Builder")
    467
                .append_slice(&[4, 5, 6]);
    468
            builder.append(true);
    469
    470
            let arr = builder.finish();
    471
            assert_eq!(2, arr.len());
    472
    473
            let elements = arr.values().as_primitive::<Int32Type>();
    474
            assert_eq!(elements.values(), &[1, 2, 3, 4, 5, 6]);
    475
        }
    476
    477
        #[test]
    478
        fn test_boxed_list_view_list_view_array_builder() {
    479
            // This test is same as `test_list_list_array_builder` but uses boxed builders.
    480
            let values_builder = make_builder(
    481
                &DataType::ListView(Arc::new(Field::new("item", DataType::Int32, true))),
    482
                10,
    483
            );
    484
            test_boxed_generic_list_view_generic_list_view_array_builder::<i32>(values_builder);
    485
        }
    486
    487
        #[test]
    488
        fn test_boxed_large_list_view_large_list_view_array_builder() {
    489
            // This test is same as `test_list_list_array_builder` but uses boxed builders.
    490
            let values_builder = make_builder(
    491
                &DataType::LargeListView(Arc::new(Field::new("item", DataType::Int32, true))),
    492
                10,
    493
            );
    494
            test_boxed_generic_list_view_generic_list_view_array_builder::<i64>(values_builder);
    495
        }
    496
    497
        fn test_boxed_generic_list_view_generic_list_view_array_builder<O>(
    498
            values_builder: Box<dyn ArrayBuilder>,
    499
        ) where
    500
            O: OffsetSizeTrait + PartialEq,
    501
        {
    502
            let mut builder: GenericListViewBuilder<O, Box<dyn ArrayBuilder>> =
    503
                GenericListViewBuilder::<O, Box<dyn ArrayBuilder>>::new(values_builder);
    504
    505
            //  [[[1, 2], [3, 4]], [[5, 6, 7], null, [8]], null, [[9, 10]]]
    506
            builder
    507
                .values()
    508
                .as_any_mut()
    509
                .downcast_mut::<GenericListViewBuilder<O, Box<dyn ArrayBuilder>>>()
    510
                .expect("should be an (Large)ListViewBuilder")
    511
                .values()
    512
                .as_any_mut()
    513
                .downcast_mut::<Int32Builder>()
    514
                .expect("should be an Int32Builder")
    515
                .append_value(1);
    516
            builder
    517
                .values()
    518
                .as_any_mut()
    519
                .downcast_mut::<GenericListViewBuilder<O, Box<dyn ArrayBuilder>>>()
    520
                .expect("should be an (Large)ListViewBuilder")
    521
                .values()
    522
                .as_any_mut()
    523
                .downcast_mut::<Int32Builder>()
    524
                .expect("should be an Int32Builder")
    525
                .append_value(2);
    526
            builder
    527
                .values()
    528
                .as_any_mut()
    529
                .downcast_mut::<GenericListViewBuilder<O, Box<dyn ArrayBuilder>>>()
    530
                .expect("should be an (Large)ListViewBuilder")
    531
                .append(true);
    532
            builder
    533
                .values()
    534
                .as_any_mut()
    535
                .downcast_mut::<GenericListViewBuilder<O, Box<dyn ArrayBuilder>>>()
    536
                .expect("should be an (Large)ListViewBuilder")
    537
                .values()
    538
                .as_any_mut()
    539
                .downcast_mut::<Int32Builder>()
    540
                .expect("should be an Int32Builder")
    541
                .append_value(3);
    542
            builder
    543
                .values()
    544
                .as_any_mut()
    545
                .downcast_mut::<GenericListViewBuilder<O, Box<dyn ArrayBuilder>>>()
    546
                .expect("should be an (Large)ListViewBuilder")
    547
                .values()
    548
                .as_any_mut()
    549
                .downcast_mut::<Int32Builder>()
    550
                .expect("should be an Int32Builder")
    551
                .append_value(4);
    552
            builder
    553
                .values()
    554
                .as_any_mut()
    555
                .downcast_mut::<GenericListViewBuilder<O, Box<dyn ArrayBuilder>>>()
    556
                .expect("should be an (Large)ListViewBuilder")
    557
                .append(true);
    558
            builder.append(true);
    559
    560
            builder
    561
                .values()
    562
                .as_any_mut()
    563
                .downcast_mut::<GenericListViewBuilder<O, Box<dyn ArrayBuilder>>>()
    564
                .expect("should be an (Large)ListViewBuilder")
    565
                .values()
    566
                .as_any_mut()
    567
                .downcast_mut::<Int32Builder>()
    568
                .expect("should be an Int32Builder")
    569
                .append_value(5);
    570
            builder
    571
                .values()
    572
                .as_any_mut()
    573
                .downcast_mut::<GenericListViewBuilder<O, Box<dyn ArrayBuilder>>>()
    574
                .expect("should be an (Large)ListViewBuilder")
    575
                .values()
    576
                .as_any_mut()
    577
                .downcast_mut::<Int32Builder>()
    578
                .expect("should be an Int32Builder")
    579
                .append_value(6);
    580
            builder
    581
                .values()
    582
                .as_any_mut()
    583
                .downcast_mut::<GenericListViewBuilder<O, Box<dyn ArrayBuilder>>>()
    584
                .expect("should be an (Large)ListViewBuilder")
    585
                .values()
    586
                .as_any_mut()
    587
                .downcast_mut::<Int32Builder>()
    588
                .expect("should be an (Large)ListViewBuilder")
    589
                .append_value(7);
    590
            builder
    591
                .values()
    592
                .as_any_mut()
    593
                .downcast_mut::<GenericListViewBuilder<O, Box<dyn ArrayBuilder>>>()
    594
                .expect("should be an (Large)ListViewBuilder")
    595
                .append(true);
    596
            builder
    597
                .values()
    598
                .as_any_mut()
    599
                .downcast_mut::<GenericListViewBuilder<O, Box<dyn ArrayBuilder>>>()
    600
                .expect("should be an (Large)ListViewBuilder")
    601
                .append(false);
    602
            builder
    603
                .values()
    604
                .as_any_mut()
    605
                .downcast_mut::<GenericListViewBuilder<O, Box<dyn ArrayBuilder>>>()
    606
                .expect("should be an (Large)ListViewBuilder")
    607
                .values()
    608
                .as_any_mut()
    609
                .downcast_mut::<Int32Builder>()
    610
                .expect("should be an Int32Builder")
    611
                .append_value(8);
    612
            builder
    613
                .values()
    614
                .as_any_mut()
    615
                .downcast_mut::<GenericListViewBuilder<O, Box<dyn ArrayBuilder>>>()
    616
                .expect("should be an (Large)ListViewBuilder")
    617
                .append(true);
    618
            builder.append(true);
    619
    620
            builder.append(false);
    621
    622
            builder
    623
                .values()
    624
                .as_any_mut()
    625
                .downcast_mut::<GenericListViewBuilder<O, Box<dyn ArrayBuilder>>>()
    626
                .expect("should be an (Large)ListViewBuilder")
    627
                .values()
    628
                .as_any_mut()
    629
                .downcast_mut::<Int32Builder>()
    630
                .expect("should be an Int32Builder")
    631
                .append_value(9);
    632
            builder
    633
                .values()
    634
                .as_any_mut()
    635
                .downcast_mut::<GenericListViewBuilder<O, Box<dyn ArrayBuilder>>>()
    636
                .expect("should be an (Large)ListViewBuilder")
    637
                .values()
    638
                .as_any_mut()
    639
                .downcast_mut::<Int32Builder>()
    640
                .expect("should be an Int32Builder")
    641
                .append_value(10);
    642
            builder
    643
                .values()
    644
                .as_any_mut()
    645
                .downcast_mut::<GenericListViewBuilder<O, Box<dyn ArrayBuilder>>>()
    646
                .expect("should be an (Large)ListViewBuilder")
    647
                .append(true);
    648
            builder.append(true);
    649
    650
            let l1 = builder.finish();
    651
            assert_eq!(4, l1.len());
    652
            assert_eq!(1, l1.null_count());
    653
            assert_eq!(l1.value_offsets(), &[0, 2, 5, 5].map(O::usize_as));
    654
            assert_eq!(l1.value_sizes(), &[2, 3, 0, 1].map(O::usize_as));
    655
    656
            let l2 = l1.values().as_list_view::<O>();
    657
            assert_eq!(6, l2.len());
    658
            assert_eq!(1, l2.null_count());
    659
            assert_eq!(l2.value_offsets(), &[0, 2, 4, 7, 7, 8].map(O::usize_as));
    660
            assert_eq!(l2.value_sizes(), &[2, 2, 3, 0, 1, 2].map(O::usize_as));
    661
    662
            let i1 = l2.values().as_primitive::<Int32Type>();
    663
            assert_eq!(10, i1.len());
    664
            assert_eq!(0, i1.null_count());
    665
            assert_eq!(i1.values(), &[1, 2, 3, 4, 5, 6, 7, 8, 9, 10]);
    666
        }
    667
    668
        #[test]
    669
        fn test_with_field() {
    670
            let field = Arc::new(Field::new("bar", DataType::Int32, false));
    671
            let mut builder = ListViewBuilder::new(Int32Builder::new()).with_field(field.clone());
    672
            builder.append_value([Some(1), Some(2), Some(3)]);
    673
            builder.append_null(); // This is fine as nullability refers to nullability of values
    674
            builder.append_value([Some(4)]);
    675
            let array = builder.finish();
    676
            assert_eq!(array.len(), 3);
    677
            assert_eq!(array.data_type(), &DataType::ListView(field.clone()));
    678
    679
            builder.append_value([Some(4), Some(5)]);
    680
            let array = builder.finish();
    681
            assert_eq!(array.data_type(), &DataType::ListView(field));
    682
            assert_eq!(array.len(), 1);
    683
        }
    684
    685
        #[test]
    686
        #[should_panic(
    687
            expected = r#"Non-nullable field of ListViewArray \"item\" cannot contain nulls"#
    688
        )]
    689
        // If a non-nullable type is declared but a null value is used, it will be intercepted by the null check.
    690
        fn test_checks_nullability() {
    691
            let field = Arc::new(Field::new("item", DataType::Int32, false));
    692
            let mut builder = ListViewBuilder::new(Int32Builder::new()).with_field(field.clone());
    693
            builder.append_value([Some(1), None]);
    694
            builder.finish();
    695
        }
    696
    697
        #[test]
    698
        #[should_panic(expected = "ListViewArray expected data type Int64 got Int32")]
    699
        // If the declared type does not match the actual appended type, it will be intercepted by type checking in the finish function.
    700
        fn test_checks_data_type() {
    701
            let field = Arc::new(Field::new("item", DataType::Int64, false));
    702
            let mut builder = ListViewBuilder::new(Int32Builder::new()).with_field(field.clone());
    703
            builder.append_value([Some(1)]);
    704
            builder.finish();
    705
        }
    706
    }