arrow_array/array/
fixed_size_list_array.rs

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
18use crate::array::print_long_array;
19use crate::builder::{FixedSizeListBuilder, PrimitiveBuilder};
20use crate::iterator::FixedSizeListIter;
21use crate::{make_array, Array, ArrayAccessor, ArrayRef, ArrowPrimitiveType};
22use arrow_buffer::buffer::NullBuffer;
23use arrow_buffer::ArrowNativeType;
24use arrow_data::{ArrayData, ArrayDataBuilder};
25use arrow_schema::{ArrowError, DataType, FieldRef};
26use std::any::Any;
27use std::sync::Arc;
28
29/// An array of [fixed length lists], similar to JSON arrays
30/// (e.g. `["A", "B"]`).
31///
32/// Lists are represented using a `values` child
33/// array where each list has a fixed size of `value_length`.
34///
35/// Use [`FixedSizeListBuilder`] to construct a [`FixedSizeListArray`].
36///
37/// # Representation
38///
39/// A [`FixedSizeListArray`] can represent a list of values of any other
40/// supported Arrow type. Each element of the `FixedSizeListArray` itself is
41/// a list which may contain NULL and non-null values,
42/// or may itself be NULL.
43///
44/// For example, this `FixedSizeListArray` stores lists of strings:
45///
46/// ```text
47/// ┌─────────────┐
48/// │    [A,B]    │
49/// ├─────────────┤
50/// │    NULL     │
51/// ├─────────────┤
52/// │   [C,NULL]  │
53/// └─────────────┘
54/// ```
55///
56/// The `values` of this `FixedSizeListArray`s are stored in a child
57/// [`StringArray`] where logical null values take up `values_length` slots in the array
58/// as shown in the following diagram. The logical values
59/// are shown on the left, and the actual `FixedSizeListArray` encoding on the right
60///
61/// ```text
62///                                 ┌ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ┐
63///                                                         ┌ ─ ─ ─ ─ ─ ─ ─ ─┐
64///  ┌─────────────┐                │     ┌───┐               ┌───┐ ┌──────┐      │
65///  │   [A,B]     │                      │ 1 │             │ │ 1 │ │  A   │ │ 0
66///  ├─────────────┤                │     ├───┤               ├───┤ ├──────┤      │
67///  │    NULL     │                      │ 0 │             │ │ 1 │ │  B   │ │ 1
68///  ├─────────────┤                │     ├───┤               ├───┤ ├──────┤      │
69///  │  [C,NULL]   │                      │ 1 │             │ │ 0 │ │ ???? │ │ 2
70///  └─────────────┘                │     └───┘               ├───┤ ├──────┤      │
71///                                                         | │ 0 │ │ ???? │ │ 3
72///  Logical Values                 │   Validity              ├───┤ ├──────┤      │
73///                                     (nulls)             │ │ 1 │ │  C   │ │ 4
74///                                 │                         ├───┤ ├──────┤      │
75///                                                         │ │ 0 │ │ ???? │ │ 5
76///                                 │                         └───┘ └──────┘      │
77///                                                         │     Values     │
78///                                 │   FixedSizeListArray        (Array)         │
79///                                                         └ ─ ─ ─ ─ ─ ─ ─ ─┘
80///                                 └ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ┘
81/// ```
82///
83/// # Example
84///
85/// ```
86/// # use std::sync::Arc;
87/// # use arrow_array::{Array, FixedSizeListArray, Int32Array};
88/// # use arrow_data::ArrayData;
89/// # use arrow_schema::{DataType, Field};
90/// # use arrow_buffer::Buffer;
91/// // Construct a value array
92/// let value_data = ArrayData::builder(DataType::Int32)
93///     .len(9)
94///     .add_buffer(Buffer::from_slice_ref(&[0, 1, 2, 3, 4, 5, 6, 7, 8]))
95///     .build()
96///     .unwrap();
97/// let list_data_type = DataType::FixedSizeList(
98///     Arc::new(Field::new_list_field(DataType::Int32, false)),
99///     3,
100/// );
101/// let list_data = ArrayData::builder(list_data_type.clone())
102///     .len(3)
103///     .add_child_data(value_data.clone())
104///     .build()
105///     .unwrap();
106/// let list_array = FixedSizeListArray::from(list_data);
107/// let list0 = list_array.value(0);
108/// let list1 = list_array.value(1);
109/// let list2 = list_array.value(2);
110///
111/// assert_eq!( &[0, 1, 2], list0.as_any().downcast_ref::<Int32Array>().unwrap().values());
112/// assert_eq!( &[3, 4, 5], list1.as_any().downcast_ref::<Int32Array>().unwrap().values());
113/// assert_eq!( &[6, 7, 8], list2.as_any().downcast_ref::<Int32Array>().unwrap().values());
114/// ```
115///
116/// [`StringArray`]: crate::array::StringArray
117/// [fixed size arrays](https://arrow.apache.org/docs/format/Columnar.html#fixed-size-list-layout)
118#[derive(Clone)]
119pub struct FixedSizeListArray {
120    data_type: DataType, // Must be DataType::FixedSizeList(value_length)
121    values: ArrayRef,
122    nulls: Option<NullBuffer>,
123    value_length: i32,
124    len: usize,
125}
126
127impl FixedSizeListArray {
128    /// Create a new [`FixedSizeListArray`] with `size` element size, panicking on failure
129    ///
130    /// # Panics
131    ///
132    /// Panics if [`Self::try_new`] returns an error
133    pub fn new(field: FieldRef, size: i32, values: ArrayRef, nulls: Option<NullBuffer>) -> Self {
134        Self::try_new(field, size, values, nulls).unwrap()
135    }
136
137    /// Create a new [`FixedSizeListArray`] from the provided parts, returning an error on failure
138    ///
139    /// # Errors
140    ///
141    /// * `size < 0`
142    /// * `values.len() / size != nulls.len()`
143    /// * `values.data_type() != field.data_type()`
144    /// * `!field.is_nullable() && !nulls.expand(size).contains(values.logical_nulls())`
145    pub fn try_new(
146        field: FieldRef,
147        size: i32,
148        values: ArrayRef,
149        nulls: Option<NullBuffer>,
150    ) -> Result<Self, ArrowError> {
151        let s = size.to_usize().ok_or_else(|| {
152            ArrowError::InvalidArgumentError(format!("Size cannot be negative, got {size}"))
153        })?;
154
155        let len = match s {
156            0 => nulls.as_ref().map(|x| x.len()).unwrap_or_default(),
157            _ => {
158                let len = values.len() / s.max(1);
159                if let Some(n) = nulls.as_ref() {
160                    if n.len() != len {
161                        return Err(ArrowError::InvalidArgumentError(format!(
162                            "Incorrect length of null buffer for FixedSizeListArray, expected {} got {}",
163                            len,
164                            n.len(),
165                        )));
166                    }
167                }
168                len
169            }
170        };
171
172        if field.data_type() != values.data_type() {
173            return Err(ArrowError::InvalidArgumentError(format!(
174                "FixedSizeListArray expected data type {} got {} for {:?}",
175                field.data_type(),
176                values.data_type(),
177                field.name()
178            )));
179        }
180
181        if let Some(a) = values.logical_nulls() {
182            let nulls_valid = field.is_nullable()
183                || nulls
184                    .as_ref()
185                    .map(|n| n.expand(size as _).contains(&a))
186                    .unwrap_or_default()
187                || (nulls.is_none() && a.null_count() == 0);
188
189            if !nulls_valid {
190                return Err(ArrowError::InvalidArgumentError(format!(
191                    "Found unmasked nulls for non-nullable FixedSizeListArray field {:?}",
192                    field.name()
193                )));
194            }
195        }
196
197        let data_type = DataType::FixedSizeList(field, size);
198        Ok(Self {
199            data_type,
200            values,
201            value_length: size,
202            nulls,
203            len,
204        })
205    }
206
207    /// Create a new [`FixedSizeListArray`] of length `len` where all values are null
208    ///
209    /// # Panics
210    ///
211    /// Panics if
212    ///
213    /// * `size < 0`
214    /// * `size * len` would overflow `usize`
215    pub fn new_null(field: FieldRef, size: i32, len: usize) -> Self {
216        let capacity = size.to_usize().unwrap().checked_mul(len).unwrap();
217        Self {
218            values: make_array(ArrayData::new_null(field.data_type(), capacity)),
219            data_type: DataType::FixedSizeList(field, size),
220            nulls: Some(NullBuffer::new_null(len)),
221            value_length: size,
222            len,
223        }
224    }
225
226    /// Deconstruct this array into its constituent parts
227    pub fn into_parts(self) -> (FieldRef, i32, ArrayRef, Option<NullBuffer>) {
228        let f = match self.data_type {
229            DataType::FixedSizeList(f, _) => f,
230            _ => unreachable!(),
231        };
232        (f, self.value_length, self.values, self.nulls)
233    }
234
235    /// Returns a reference to the values of this list.
236    pub fn values(&self) -> &ArrayRef {
237        &self.values
238    }
239
240    /// Returns a clone of the value type of this list.
241    pub fn value_type(&self) -> DataType {
242        self.values.data_type().clone()
243    }
244
245    /// Returns ith value of this list array.
246    ///
247    /// Note: This method does not check for nulls and the value is arbitrary
248    /// (but still well-defined) if [`is_null`](Self::is_null) returns true for the index.
249    ///
250    /// # Panics
251    /// Panics if index `i` is out of bounds
252    pub fn value(&self, i: usize) -> ArrayRef {
253        self.values
254            .slice(self.value_offset_at(i), self.value_length() as usize)
255    }
256
257    /// Returns the offset for value at index `i`.
258    ///
259    /// Note this doesn't do any bound checking, for performance reason.
260    #[inline]
261    pub fn value_offset(&self, i: usize) -> i32 {
262        self.value_offset_at(i) as i32
263    }
264
265    /// Returns the length for an element.
266    ///
267    /// All elements have the same length as the array is a fixed size.
268    #[inline]
269    pub const fn value_length(&self) -> i32 {
270        self.value_length
271    }
272
273    #[inline]
274    const fn value_offset_at(&self, i: usize) -> usize {
275        i * self.value_length as usize
276    }
277
278    /// Returns a zero-copy slice of this array with the indicated offset and length.
279    pub fn slice(&self, offset: usize, len: usize) -> Self {
280        assert!(
281            offset.saturating_add(len) <= self.len,
282            "the length + offset of the sliced FixedSizeListArray cannot exceed the existing length"
283        );
284        let size = self.value_length as usize;
285
286        Self {
287            data_type: self.data_type.clone(),
288            values: self.values.slice(offset * size, len * size),
289            nulls: self.nulls.as_ref().map(|n| n.slice(offset, len)),
290            value_length: self.value_length,
291            len,
292        }
293    }
294
295    /// Creates a [`FixedSizeListArray`] from an iterator of primitive values
296    /// # Example
297    /// ```
298    /// # use arrow_array::FixedSizeListArray;
299    /// # use arrow_array::types::Int32Type;
300    ///
301    /// let data = vec![
302    ///    Some(vec![Some(0), Some(1), Some(2)]),
303    ///    None,
304    ///    Some(vec![Some(3), None, Some(5)]),
305    ///    Some(vec![Some(6), Some(7), Some(45)]),
306    /// ];
307    /// let list_array = FixedSizeListArray::from_iter_primitive::<Int32Type, _, _>(data, 3);
308    /// println!("{:?}", list_array);
309    /// ```
310    pub fn from_iter_primitive<T, P, I>(iter: I, length: i32) -> Self
311    where
312        T: ArrowPrimitiveType,
313        P: IntoIterator<Item = Option<<T as ArrowPrimitiveType>::Native>>,
314        I: IntoIterator<Item = Option<P>>,
315    {
316        let l = length as usize;
317        let iter = iter.into_iter();
318        let size_hint = iter.size_hint().0;
319        let mut builder = FixedSizeListBuilder::with_capacity(
320            PrimitiveBuilder::<T>::with_capacity(size_hint * l),
321            length,
322            size_hint,
323        );
324
325        for i in iter {
326            match i {
327                Some(p) => {
328                    for t in p {
329                        builder.values().append_option(t);
330                    }
331                    builder.append(true);
332                }
333                None => {
334                    builder.values().append_nulls(l);
335                    builder.append(false)
336                }
337            }
338        }
339        builder.finish()
340    }
341
342    /// constructs a new iterator
343    pub fn iter(&self) -> FixedSizeListIter<'_> {
344        FixedSizeListIter::new(self)
345    }
346}
347
348impl From<ArrayData> for FixedSizeListArray {
349    fn from(data: ArrayData) -> Self {
350        let value_length = match data.data_type() {
351            DataType::FixedSizeList(_, len) => *len,
352            data_type => {
353                panic!("FixedSizeListArray data should contain a FixedSizeList data type, got {data_type}")
354            }
355        };
356
357        let size = value_length as usize;
358        let values =
359            make_array(data.child_data()[0].slice(data.offset() * size, data.len() * size));
360        Self {
361            data_type: data.data_type().clone(),
362            values,
363            nulls: data.nulls().cloned(),
364            value_length,
365            len: data.len(),
366        }
367    }
368}
369
370impl From<FixedSizeListArray> for ArrayData {
371    fn from(array: FixedSizeListArray) -> Self {
372        let builder = ArrayDataBuilder::new(array.data_type)
373            .len(array.len)
374            .nulls(array.nulls)
375            .child_data(vec![array.values.to_data()]);
376
377        unsafe { builder.build_unchecked() }
378    }
379}
380
381impl Array for FixedSizeListArray {
382    fn as_any(&self) -> &dyn Any {
383        self
384    }
385
386    fn to_data(&self) -> ArrayData {
387        self.clone().into()
388    }
389
390    fn into_data(self) -> ArrayData {
391        self.into()
392    }
393
394    fn data_type(&self) -> &DataType {
395        &self.data_type
396    }
397
398    fn slice(&self, offset: usize, length: usize) -> ArrayRef {
399        Arc::new(self.slice(offset, length))
400    }
401
402    fn len(&self) -> usize {
403        self.len
404    }
405
406    fn is_empty(&self) -> bool {
407        self.len == 0
408    }
409
410    fn shrink_to_fit(&mut self) {
411        self.values.shrink_to_fit();
412        if let Some(nulls) = &mut self.nulls {
413            nulls.shrink_to_fit();
414        }
415    }
416
417    fn offset(&self) -> usize {
418        0
419    }
420
421    fn nulls(&self) -> Option<&NullBuffer> {
422        self.nulls.as_ref()
423    }
424
425    fn logical_null_count(&self) -> usize {
426        // More efficient that the default implementation
427        self.null_count()
428    }
429
430    fn get_buffer_memory_size(&self) -> usize {
431        let mut size = self.values.get_buffer_memory_size();
432        if let Some(n) = self.nulls.as_ref() {
433            size += n.buffer().capacity();
434        }
435        size
436    }
437
438    fn get_array_memory_size(&self) -> usize {
439        let mut size = std::mem::size_of::<Self>() + self.values.get_array_memory_size();
440        if let Some(n) = self.nulls.as_ref() {
441            size += n.buffer().capacity();
442        }
443        size
444    }
445}
446
447impl ArrayAccessor for FixedSizeListArray {
448    type Item = ArrayRef;
449
450    fn value(&self, index: usize) -> Self::Item {
451        FixedSizeListArray::value(self, index)
452    }
453
454    unsafe fn value_unchecked(&self, index: usize) -> Self::Item {
455        FixedSizeListArray::value(self, index)
456    }
457}
458
459impl std::fmt::Debug for FixedSizeListArray {
460    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
461        write!(f, "FixedSizeListArray<{}>\n[\n", self.value_length())?;
462        print_long_array(self, f, |array, index, f| {
463            std::fmt::Debug::fmt(&array.value(index), f)
464        })?;
465        write!(f, "]")
466    }
467}
468
469impl ArrayAccessor for &FixedSizeListArray {
470    type Item = ArrayRef;
471
472    fn value(&self, index: usize) -> Self::Item {
473        FixedSizeListArray::value(self, index)
474    }
475
476    unsafe fn value_unchecked(&self, index: usize) -> Self::Item {
477        FixedSizeListArray::value(self, index)
478    }
479}
480
481#[cfg(test)]
482mod tests {
483    use arrow_buffer::{bit_util, BooleanBuffer, Buffer};
484    use arrow_schema::Field;
485
486    use crate::cast::AsArray;
487    use crate::types::Int32Type;
488    use crate::{new_empty_array, Int32Array};
489
490    use super::*;
491
492    #[test]
493    fn test_fixed_size_list_array() {
494        // Construct a value array
495        let value_data = ArrayData::builder(DataType::Int32)
496            .len(9)
497            .add_buffer(Buffer::from_slice_ref([0, 1, 2, 3, 4, 5, 6, 7, 8]))
498            .build()
499            .unwrap();
500
501        // Construct a list array from the above two
502        let list_data_type =
503            DataType::FixedSizeList(Arc::new(Field::new_list_field(DataType::Int32, false)), 3);
504        let list_data = ArrayData::builder(list_data_type.clone())
505            .len(3)
506            .add_child_data(value_data.clone())
507            .build()
508            .unwrap();
509        let list_array = FixedSizeListArray::from(list_data);
510
511        assert_eq!(value_data, list_array.values().to_data());
512        assert_eq!(DataType::Int32, list_array.value_type());
513        assert_eq!(3, list_array.len());
514        assert_eq!(0, list_array.null_count());
515        assert_eq!(6, list_array.value_offset(2));
516        assert_eq!(3, list_array.value_length());
517        assert_eq!(0, list_array.value(0).as_primitive::<Int32Type>().value(0));
518        for i in 0..3 {
519            assert!(list_array.is_valid(i));
520            assert!(!list_array.is_null(i));
521        }
522
523        // Now test with a non-zero offset
524        let list_data = ArrayData::builder(list_data_type)
525            .len(2)
526            .offset(1)
527            .add_child_data(value_data.clone())
528            .build()
529            .unwrap();
530        let list_array = FixedSizeListArray::from(list_data);
531
532        assert_eq!(value_data.slice(3, 6), list_array.values().to_data());
533        assert_eq!(DataType::Int32, list_array.value_type());
534        assert_eq!(2, list_array.len());
535        assert_eq!(0, list_array.null_count());
536        assert_eq!(3, list_array.value(0).as_primitive::<Int32Type>().value(0));
537        assert_eq!(3, list_array.value_offset(1));
538        assert_eq!(3, list_array.value_length());
539    }
540
541    #[test]
542    #[should_panic(expected = "assertion failed: (offset + length) <= self.len()")]
543    // Different error messages, so skip for now
544    // https://github.com/apache/arrow-rs/issues/1545
545    #[cfg(not(feature = "force_validate"))]
546    fn test_fixed_size_list_array_unequal_children() {
547        // Construct a value array
548        let value_data = ArrayData::builder(DataType::Int32)
549            .len(8)
550            .add_buffer(Buffer::from_slice_ref([0, 1, 2, 3, 4, 5, 6, 7]))
551            .build()
552            .unwrap();
553
554        // Construct a list array from the above two
555        let list_data_type =
556            DataType::FixedSizeList(Arc::new(Field::new_list_field(DataType::Int32, false)), 3);
557        let list_data = unsafe {
558            ArrayData::builder(list_data_type)
559                .len(3)
560                .add_child_data(value_data)
561                .build_unchecked()
562        };
563        drop(FixedSizeListArray::from(list_data));
564    }
565
566    #[test]
567    fn test_fixed_size_list_array_slice() {
568        // Construct a value array
569        let value_data = ArrayData::builder(DataType::Int32)
570            .len(10)
571            .add_buffer(Buffer::from_slice_ref([0, 1, 2, 3, 4, 5, 6, 7, 8, 9]))
572            .build()
573            .unwrap();
574
575        // Set null buts for the nested array:
576        //  [[0, 1], null, null, [6, 7], [8, 9]]
577        // 01011001 00000001
578        let mut null_bits: [u8; 1] = [0; 1];
579        bit_util::set_bit(&mut null_bits, 0);
580        bit_util::set_bit(&mut null_bits, 3);
581        bit_util::set_bit(&mut null_bits, 4);
582
583        // Construct a fixed size list array from the above two
584        let list_data_type =
585            DataType::FixedSizeList(Arc::new(Field::new_list_field(DataType::Int32, false)), 2);
586        let list_data = ArrayData::builder(list_data_type)
587            .len(5)
588            .add_child_data(value_data.clone())
589            .null_bit_buffer(Some(Buffer::from(null_bits)))
590            .build()
591            .unwrap();
592        let list_array = FixedSizeListArray::from(list_data);
593
594        assert_eq!(value_data, list_array.values().to_data());
595        assert_eq!(DataType::Int32, list_array.value_type());
596        assert_eq!(5, list_array.len());
597        assert_eq!(2, list_array.null_count());
598        assert_eq!(6, list_array.value_offset(3));
599        assert_eq!(2, list_array.value_length());
600
601        let sliced_array = list_array.slice(1, 4);
602        assert_eq!(4, sliced_array.len());
603        assert_eq!(2, sliced_array.null_count());
604
605        for i in 0..sliced_array.len() {
606            if bit_util::get_bit(&null_bits, 1 + i) {
607                assert!(sliced_array.is_valid(i));
608            } else {
609                assert!(sliced_array.is_null(i));
610            }
611        }
612
613        // Check offset and length for each non-null value.
614        let sliced_list_array = sliced_array
615            .as_any()
616            .downcast_ref::<FixedSizeListArray>()
617            .unwrap();
618        assert_eq!(2, sliced_list_array.value_length());
619        assert_eq!(4, sliced_list_array.value_offset(2));
620        assert_eq!(6, sliced_list_array.value_offset(3));
621    }
622
623    #[test]
624    #[should_panic(expected = "the offset of the new Buffer cannot exceed the existing length")]
625    fn test_fixed_size_list_array_index_out_of_bound() {
626        // Construct a value array
627        let value_data = ArrayData::builder(DataType::Int32)
628            .len(10)
629            .add_buffer(Buffer::from_slice_ref([0, 1, 2, 3, 4, 5, 6, 7, 8, 9]))
630            .build()
631            .unwrap();
632
633        // Set null buts for the nested array:
634        //  [[0, 1], null, null, [6, 7], [8, 9]]
635        // 01011001 00000001
636        let mut null_bits: [u8; 1] = [0; 1];
637        bit_util::set_bit(&mut null_bits, 0);
638        bit_util::set_bit(&mut null_bits, 3);
639        bit_util::set_bit(&mut null_bits, 4);
640
641        // Construct a fixed size list array from the above two
642        let list_data_type =
643            DataType::FixedSizeList(Arc::new(Field::new_list_field(DataType::Int32, false)), 2);
644        let list_data = ArrayData::builder(list_data_type)
645            .len(5)
646            .add_child_data(value_data)
647            .null_bit_buffer(Some(Buffer::from(null_bits)))
648            .build()
649            .unwrap();
650        let list_array = FixedSizeListArray::from(list_data);
651
652        list_array.value(10);
653    }
654
655    #[test]
656    fn test_fixed_size_list_constructors() {
657        let values = Arc::new(Int32Array::from_iter([
658            Some(1),
659            Some(2),
660            None,
661            None,
662            Some(3),
663            Some(4),
664        ]));
665
666        let field = Arc::new(Field::new_list_field(DataType::Int32, true));
667        let list = FixedSizeListArray::new(field.clone(), 2, values.clone(), None);
668        assert_eq!(list.len(), 3);
669
670        let nulls = NullBuffer::new_null(3);
671        let list = FixedSizeListArray::new(field.clone(), 2, values.clone(), Some(nulls));
672        assert_eq!(list.len(), 3);
673
674        let list = FixedSizeListArray::new(field.clone(), 4, values.clone(), None);
675        assert_eq!(list.len(), 1);
676
677        let err = FixedSizeListArray::try_new(field.clone(), -1, values.clone(), None).unwrap_err();
678        assert_eq!(
679            err.to_string(),
680            "Invalid argument error: Size cannot be negative, got -1"
681        );
682
683        let list = FixedSizeListArray::new(field.clone(), 0, values.clone(), None);
684        assert_eq!(list.len(), 0);
685
686        let nulls = NullBuffer::new_null(2);
687        let err = FixedSizeListArray::try_new(field, 2, values.clone(), Some(nulls)).unwrap_err();
688        assert_eq!(err.to_string(), "Invalid argument error: Incorrect length of null buffer for FixedSizeListArray, expected 3 got 2");
689
690        let field = Arc::new(Field::new_list_field(DataType::Int32, false));
691        let err = FixedSizeListArray::try_new(field.clone(), 2, values.clone(), None).unwrap_err();
692        assert_eq!(err.to_string(), "Invalid argument error: Found unmasked nulls for non-nullable FixedSizeListArray field \"item\"");
693
694        // Valid as nulls in child masked by parent
695        let nulls = NullBuffer::new(BooleanBuffer::new(Buffer::from([0b0000101]), 0, 3));
696        FixedSizeListArray::new(field, 2, values.clone(), Some(nulls));
697
698        let field = Arc::new(Field::new_list_field(DataType::Int64, true));
699        let err = FixedSizeListArray::try_new(field, 2, values, None).unwrap_err();
700        assert_eq!(err.to_string(), "Invalid argument error: FixedSizeListArray expected data type Int64 got Int32 for \"item\"");
701    }
702
703    #[test]
704    fn empty_fixed_size_list() {
705        let field = Arc::new(Field::new_list_field(DataType::Int32, true));
706        let nulls = NullBuffer::new_null(2);
707        let values = new_empty_array(&DataType::Int32);
708        let list = FixedSizeListArray::new(field.clone(), 0, values, Some(nulls));
709        assert_eq!(list.len(), 2);
710    }
711}
arrow_array/array/fixed_size_list_array.rs

arrow_array/array/
fixed_size_list_array.rs
