datafusion_spark/function/datetime/
last_day.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 std::any::Any;
19use std::sync::Arc;
20
21use arrow::array::{ArrayRef, AsArray, Date32Array};
22use arrow::datatypes::{DataType, Date32Type, Field, FieldRef};
23use chrono::{Datelike, Duration, NaiveDate};
24use datafusion_common::utils::take_function_args;
25use datafusion_common::{Result, ScalarValue, exec_datafusion_err, internal_err};
26use datafusion_expr::{
27    ColumnarValue, ReturnFieldArgs, ScalarFunctionArgs, ScalarUDFImpl, Signature,
28    Volatility,
29};
30
31#[derive(Debug, PartialEq, Eq, Hash)]
32pub struct SparkLastDay {
33    signature: Signature,
34}
35
36impl Default for SparkLastDay {
37    fn default() -> Self {
38        Self::new()
39    }
40}
41
42impl SparkLastDay {
43    pub fn new() -> Self {
44        Self {
45            signature: Signature::exact(vec![DataType::Date32], Volatility::Immutable),
46        }
47    }
48}
49
50impl ScalarUDFImpl for SparkLastDay {
51    fn as_any(&self) -> &dyn Any {
52        self
53    }
54
55    fn name(&self) -> &str {
56        "last_day"
57    }
58
59    fn signature(&self) -> &Signature {
60        &self.signature
61    }
62
63    fn return_type(&self, _arg_types: &[DataType]) -> Result<DataType> {
64        internal_err!("return_field_from_args should be used instead")
65    }
66
67    fn return_field_from_args(&self, args: ReturnFieldArgs) -> Result<FieldRef> {
68        let Some(field) = args.arg_fields.first() else {
69            return internal_err!("Spark `last_day` expects exactly one argument");
70        };
71
72        Ok(Arc::new(Field::new(
73            self.name(),
74            DataType::Date32,
75            field.is_nullable(),
76        )))
77    }
78
79    fn invoke_with_args(&self, args: ScalarFunctionArgs) -> Result<ColumnarValue> {
80        let ScalarFunctionArgs { args, .. } = args;
81        let [arg] = take_function_args("last_day", args)?;
82        match arg {
83            ColumnarValue::Scalar(ScalarValue::Date32(days)) => {
84                if let Some(days) = days {
85                    Ok(ColumnarValue::Scalar(ScalarValue::Date32(Some(
86                        spark_last_day(days)?,
87                    ))))
88                } else {
89                    Ok(ColumnarValue::Scalar(ScalarValue::Date32(None)))
90                }
91            }
92            ColumnarValue::Array(array) => {
93                let result = match array.data_type() {
94                    DataType::Date32 => {
95                        let result: Date32Array = array
96                            .as_primitive::<Date32Type>()
97                            .try_unary(spark_last_day)?
98                            .with_data_type(DataType::Date32);
99                        Ok(Arc::new(result) as ArrayRef)
100                    }
101                    other => {
102                        internal_err!(
103                            "Unsupported data type {other:?} for Spark function `last_day`"
104                        )
105                    }
106                }?;
107                Ok(ColumnarValue::Array(result))
108            }
109            other => {
110                internal_err!("Unsupported arg {other:?} for Spark function `last_day")
111            }
112        }
113    }
114}
115
116fn spark_last_day(days: i32) -> Result<i32> {
117    let date = Date32Type::to_naive_date(days);
118
119    let (year, month) = (date.year(), date.month());
120    let (next_year, next_month) = if month == 12 {
121        (year + 1, 1)
122    } else {
123        (year, month + 1)
124    };
125
126    let first_day_next_month = NaiveDate::from_ymd_opt(next_year, next_month, 1)
127        .ok_or_else(|| {
128            exec_datafusion_err!(
129                "Spark `last_day`: Unable to parse date from {next_year}, {next_month}, 1"
130            )
131        })?;
132
133    Ok(Date32Type::from_naive_date(
134        first_day_next_month - Duration::days(1),
135    ))
136}
137
138#[cfg(test)]
139mod tests {
140    use super::*;
141    use crate::function::utils::test::test_scalar_function;
142    use arrow::array::{Array, Date32Array};
143    use arrow::datatypes::Field;
144    use datafusion_common::ScalarValue;
145    use datafusion_expr::{ColumnarValue, ReturnFieldArgs};
146
147    #[test]
148    fn test_last_day_nullability_matches_input() {
149        let func = SparkLastDay::new();
150
151        let non_nullable_arg = Arc::new(Field::new("arg", DataType::Date32, false));
152        let nullable_arg = Arc::new(Field::new("arg", DataType::Date32, true));
153
154        let non_nullable_out = func
155            .return_field_from_args(ReturnFieldArgs {
156                arg_fields: &[Arc::clone(&non_nullable_arg)],
157                scalar_arguments: &[None],
158            })
159            .expect("non-nullable arg should succeed");
160        assert_eq!(non_nullable_out.data_type(), &DataType::Date32);
161        assert!(!non_nullable_out.is_nullable());
162
163        let nullable_out = func
164            .return_field_from_args(ReturnFieldArgs {
165                arg_fields: &[Arc::clone(&nullable_arg)],
166                scalar_arguments: &[None],
167            })
168            .expect("nullable arg should succeed");
169        assert_eq!(nullable_out.data_type(), &DataType::Date32);
170        assert!(nullable_out.is_nullable());
171    }
172
173    #[test]
174    fn test_last_day_scalar_evaluation() {
175        test_scalar_function!(
176            SparkLastDay::new(),
177            vec![ColumnarValue::Scalar(ScalarValue::Date32(Some(0)))],
178            Ok(Some(30)),
179            i32,
180            DataType::Date32,
181            Date32Array
182        );
183
184        test_scalar_function!(
185            SparkLastDay::new(),
186            vec![ColumnarValue::Scalar(ScalarValue::Date32(None))],
187            Ok(None),
188            i32,
189            DataType::Date32,
190            Date32Array
191        );
192    }
193}
datafusion_spark/function/datetime/last_day.rs

datafusion_spark/function/datetime/
last_day.rs
