feat: Implement Spark-compatible CAST from string to integral types (a…

…pache#307)

core/Cargo.toml

@@ -118,3 +118,6 @@ harness = false
 name = "row_columnar"
 harness = false
 
+[[bench]]
+name = "cast"
+harness = false

core/benches/cast.rs

@@ -0,0 +1,85 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+use arrow_array::{builder::StringBuilder, RecordBatch};
+use arrow_schema::{DataType, Field, Schema};
+use comet::execution::datafusion::expressions::cast::{Cast, EvalMode};
+use criterion::{criterion_group, criterion_main, Criterion};
+use datafusion_physical_expr::{expressions::Column, PhysicalExpr};
+use std::sync::Arc;
+
+fn criterion_benchmark(c: &mut Criterion) {
+    let schema = Arc::new(Schema::new(vec![Field::new("a", DataType::Utf8, true)]));
+    let mut b = StringBuilder::new();
+    for i in 0..1000 {
+        if i % 10 == 0 {
+            b.append_null();
+        } else if i % 2 == 0 {
+            b.append_value(format!("{}", rand::random::<f64>()));
+        } else {
+            b.append_value(format!("{}", rand::random::<i64>()));
+        }
+    }
+    let array = b.finish();
+    let batch = RecordBatch::try_new(schema.clone(), vec![Arc::new(array)]).unwrap();
+    let expr = Arc::new(Column::new("a", 0));
+    let timezone = "".to_string();
+    let cast_string_to_i8 = Cast::new(
+        expr.clone(),
+        DataType::Int8,
+        EvalMode::Legacy,
+        timezone.clone(),
+    );
+    let cast_string_to_i16 = Cast::new(
+        expr.clone(),
+        DataType::Int16,
+        EvalMode::Legacy,
+        timezone.clone(),
+    );
+    let cast_string_to_i32 = Cast::new(
+        expr.clone(),
+        DataType::Int32,
+        EvalMode::Legacy,
+        timezone.clone(),
+    );
+    let cast_string_to_i64 = Cast::new(expr, DataType::Int64, EvalMode::Legacy, timezone);
+
+    let mut group = c.benchmark_group("cast");
+    group.bench_function("cast_string_to_i8", |b| {
+        b.iter(|| cast_string_to_i8.evaluate(&batch).unwrap());
+    });
+    group.bench_function("cast_string_to_i16", |b| {
+        b.iter(|| cast_string_to_i16.evaluate(&batch).unwrap());
+    });
+    group.bench_function("cast_string_to_i32", |b| {
+        b.iter(|| cast_string_to_i32.evaluate(&batch).unwrap());
+    });
+    group.bench_function("cast_string_to_i64", |b| {
+        b.iter(|| cast_string_to_i64.evaluate(&batch).unwrap());
+    });
+}
+
+fn config() -> Criterion {
+    Criterion::default()
+}
+
+criterion_group! {
+    name = benches;
+    config = config();
+    targets = criterion_benchmark
+}
+criterion_main!(benches);